Researching the Luftwaffe through Prisoner Interrogations

[Bruce Dennis]

"SECRET A. D. I. (K) Report No. 369/1945
THE FOLLOWING INFORMATION HAS BEEN OBTAINED FROM P/W
AS THE STATEMENTS HAVE NOT AS YET BEEN VERIFIED, NO
MENTION OF THEM SHOULD BE MADE IN INTELLIGENCE
SUMMARIES OF COMMANDS OR LOWER FORMATIONS, NOR SHOULD
THEY BE ACCEPTED UNTIL COMMENTED ON AIR MINISTRY
INTELLIGENCE SUMMARIES OR SPECIAL COMMUNICATIONS.
RADIO AND RADAR EQUIPMENT IN THE LUFTWAFFE – VI.
Target Homing for Night Fighters.
German early warning Ground Radar.
1. This report is the sixth of the series dealing with radio
and radar equipment in the Luftwaffe. As in the case of the
previous five reports (A.D.I.(K) 343, 357, 362, 363 and
365/1945),it is based on interrogation of General
Nachrichtenführer MARTINI, Director General of Signals, and
some members of his staff, and has been supported by a number
of relevant documents of recent date which were in the
possession of the General's Chief of Staff.
POLICY AND REQUIREMENTS
2. Members of General MARTINI’s staff have often repeated
a catch phrase "Aller Funkverkehr ist Landesverrrat" - all
radio traffic is treasonable, and the G.A.F. were only too
well aware that a transmission of any type could be listened
in to by the Allies and then D/F'd. They were, therefore,
fully aware of the opportunities of homing on to
transmissions from Allied aircraft and so when airborne
countermeasures against the Freya ground installations were
first taken by the Allies, Köthen developed an apparatus
which would enable a German night fighter to home on to the
source of the jamming transmission.
3. This equipment was called Freya-Halbe (Halbe = half
signifying that it was a radar apparatus equipped with the
receiver half only and not the transmitter), and it was
tried out at Werneuchen in early 1943. The trials were
successfully completed by about June of that year and it was
then demonstrated to the authorities for use by the G.A.F.
night fighter units.
4. At that time, however, the German night fighter force was
commanded by General KAMMHUBER who was the creator of the
Kammhuber line and whose night fighter organisation relied
essentially on ground-controlled night fighter aircraft
operating in comparatively limited boxes. The suggestion of
homing on to jammers was turned down by KAMMHUBER out of hand
because he was a rabid opponent of any form of freelance
night fighting and insisted on strict adherence by his
aircraft to the limits of their box.
5. With the discovery of Monica and the development of the
Rosendahl and later the Flensburg homers on to Monica,
KAMMUBER still maintained his obstinate stand against any
departure from the box system of control. It was, therefore,
not until General SCHMIDT assumed the control of the night
fighting force in November 1943 and proceeded to introduce
freelance methods that D/F homers on to transmissions from
the bombers could be used operationally.
6. Although the technical experts were satisfied that the
homers on to transmissions of metric wavelengths were
successful, aircrews seemed to be unable to use them well and
results obtained were never wholly satisfactory. Exactly the
same applied to Naxos for homing on to H2S is its early days,
particularly when a number of minor troubles were still being
encountered with its electrical parts and, though it was
available in January 1944, for the first three or four months
comparatively little use was made of an excellent homing
device.
7. By about Easter 1941 the early troubles of Naxos were
overcome and crews began to gain confidence in its use; with
the success of Naxos reliance on all types of homing apparatus
increased. At this stage, however the R.A.F. had almost ceased
to use Monica and Naxos remained the only important set of its
type.
8. In view of the change of policy governing night fighter
operations experimental D/F receivers known as X-Halbe were
designed capable of adaptation to any metric wavelength which
might be used by the Allies. In addition one of the tactical
requirements laid down after 1943 for all future A.I. sets was
that provision should be made for the switching off of the
transmitter portion so that the receiver could act as a homer
on to any airborne jammers employed by the Allies. Naxos and
Korfu Z which covered the 1.5 cm. to 20 cm. band already
existed.
9. As R/T and W/T Jamming became more intense and even
ground control by commentary broke down, increasing use was
made of homing on to the bomber stream by means of receivers
of the Naxos type but there remained always the serious
disadvantage that these receivers did not supply range. It was
claimed that both Naxos and Korfu were so sensitive that the
bomber stream could be picked up at a range of 200 km. and
that in consequence useless chases often ensued. Estimates of
range had to be made by deduction and even in the case of
experienced crews the estimate of range by indirect means was
not always reliable.
10. Short mention is made below of another form of homing
device, the Kiel Z, which attempted to use the infra-red
radiations from the exhaust stubs of the bomber. A fuller
description of the Kiel Z was given in A.D.I.(K) 390/1945,
paras 41 to 48.
FREYA-HALBE.
11. The Freya-Halbe, officially known as the FuGe. 221, was
designed early in 1943 to home on to airborne Freya jammers
but owing to KAMMHUBER's opposition to freelance night
fighting was not adopted. Towards the end of 1943 when freelance
operations were introduced it was proposed to install
the twenty-five Freya-Halbe sets which had been manufactured
but, when they were indented for, it was found that the makers
had used various parts for manufacturing other apparatus and
that the sets had been virtually consumed as spares. Freya-
Halbe was, therefore, never used on operations.
ROSENDAHL-HALBE.
12. The first Monica set obtained by the Germans was
recovered from a British four-engined bomber which was shot
down over the town of Rosendahl in Holland and the name of
Rosendahl or FuGe. 221.A was then given to the D/F equipment
developed for homing on to Monica.
13. According to one of the P/W who had flown the trials with
Rosendahl, it was quite successful, and gave good D/F until
the night fighter came within 4 km. of its target, after which
the D/F became unreliable. For this reason the general
introduction of Rosendahl-Halbe was delayed.
14. It was ultimately discovered that the polarisation of
the receiver aerials was at 90° to that used by the bombers
and it was assumed that this was the cause of the poor D/F. For
some technical reason it was not found possible to twist the
aerial through 90° in order to obtain the right polarisation
and by the time that these difficulties had been overcome the
R.A.F. use of Monica had ceased.
15. An interesting experiment was carried out with Rosendahl-
Halbe when a set of Rosendahl aerials was mounted round a 150
cm. searchlight. The idea was to align the searchlight beam on
to an aircraft transmitting Monica. Considerable difficulty
was encountered in getting the searchlight beam and the axis
of the receiving lobe to coincide and by the time this had
being achieved R.A.F. bombers were no longer using Monica.
16. The Flensburg, officially known as FuGe.227, was another
attempt at solving the problem of producing a homer to D/F on
to Monica transmission. Difficulty was encountered with D/F
properties but the set was satisfactorily selective and could
discriminate between a large number of signals by tuning to
both the r.f. and p.r.f. It was used to a limited extent in
night fighter operations.
17. With the cessation of the use of Monica the original
Flensburg became known as Flensburg I and a series of other
F1ensburgs, numbered from II to VI, were manufactured to cover
the frequencies used by the mandrel screen and other Freya
jammers. The frequencies as given in documents were:-
Flensburg I 1.3 m. to 1.75 m. against Monica.
Flensburg II 1.7 m. to 2.6 m. against Freya A and B
band and Jagdschloss jammers.
Flensburg III
Flensburg IV
2.3 m. to 3.8 m.) against SN 2 and Freya
3.8 m. to 5.0 m.) C frequency jammers.
Flensburg V 25 cm, band against 25 cm. P.P.I. ground
radar jammers.
Flensburg VI 50 cm. band against Würzburg jammers.
18. It was not known to what extent these additional
Flensburgs had been used in operations. They were considered
to be a successful solution to the homing problem except for
the fact that the large aerials, particularly on the Freya
frequencies, reduced the speed of the aircraft considerably.
A.G.L.T.
19. The interrogation of British prisoners of war had
provided information with regard to Village Inn and some
details of it were known. It was thought to operate on a
centimetre wavelength and pieces of equipment had been found.
Nevertheless, P/W were convinced that though preparations for
using it had been made it had not yet been employed
operationally.
X-HALBE.
20. This was the designation of the airborne receiver which
could be adapted for D/F'ing any new metric radar that was
observed by the monitoring service.
NAXOS.
21. The Naxos, known as the FuGe.350, was a detector set
which received all transmissions on the 8 to 12 cm, band but
could not discriminate between different wavelengths in the
band.
22. The problem of producing a homer on to a beamed
transmission rotating at 60 r.p.m., as in the case of H2S, was
first tackled in March 1943, some two months after the
discovery of H2S. Little progress was made until an engineer
hit on the idea of getting continuous presentation of the
signals received by employing aerials rotating about twenty
times faster than those of the transmitter. The G.A.F. signals
staff were so impressed with the ease with which it was
possible to home on to a slowly rotating beam such as that of
the H2S that one of the requirements for the Berlin A was that
its rate of rotation in searching should be very high to
ensure that the Naxos solution to the homing problem could not
be employed against it.
23. The first trials with the Naxos were flown in December
1943 at Werneuchen and the first operational Gruppe to be
equipped with the set had it installed in all their aircraft
by the 25th January 1944.
24. A whole series of Naxos sub-types were produced and of
those the following were mentioned:-
Naxos Z. = (Zielanflug = Target Approach): was the original
homing device operating on the 8 to 12 cm. band; it could
not differentiate between frequencies in the band so that
if there was more than one H2S aircraft in the
neighbourhood, a confused picture was obtained.
Naxos ZR. (R Rückwärts = Backward): employed aerials placed
both above and below the after part of the fuselage of the
Ju.88 and served as a backward warning device for the
approach of British night fighters using Mark VIII or Mark
XI on the 9 cm. wavelength.
Naxos ZX. (X = X-band = 3 cm. band): was the 3 cm.
equivalent of the original Naxos Z. It operated on the 2.5
cm. - 4 cm. band.
Naxos RX. was the 3 cm. equivalent of the Naxos R and was
used as a backward warner against 3 cm. A.I.
Naxos ZD. was a combined homer for both the 9 cm. and the
3 cm. bands. The 3 cm. aerial rotated on the same axis but
above the 9 cm. aerials.
25. As stated, the value of Naxos was first appreciated by
crews in the early summer of 1944 when the increase in British
jamming had reached such a pitch that communications with the
ground were affected and it was difficult to find the bomber
stream. The picture obtained by Naxos, however, was nonselective
and it was not always possible to home on to a
single aircraft unless the aircraft in question was separated
from the others in the stream. On the other hand Naxos made it
easy to locate the bomber stream, which at that period was the
main preoccupation of the G.A.F.
26. Although estimate of range could be gained if the height
at which the bombers were flying was known, since, by climbing
and determining at what point the Rotterdam signals were no
longer picked up, the night fighter aircraft could judge the
distance of the transmitting aircraft. A full description of
the method of approach employed appeared in A.D.I.(K)
125/1945. paras. 93-98.
KORFU Z.
27. The original Korfu set, otherwise known as the FuGe.351,
was a development of a superhet receiver designed for
frequency modulated 9 cm. carrier communications purposes.
After the discovery of H2S it was adapted for use by the
German "Y" service and towards the end of the war was further
modified for use as an airborne set and then became known as
the Korfu Z or FuGe.351Z.
28. The aerials employed were of the Naxos type and gave the
relative bearing of the transmitter but the advantage of the
Korfu Z lay in the fact that it could be sharply tuned and
could, therefore, home on to individual aircraft.
29. It was also hoped that with the help of the Korfu Z night
fighters would be able to differentiate between H2S and 9 cm.
A.I. which the Germans presumed used different sections of the
9.0 to 9.3 cm. band. In this connection, as mentioned in
A.D.I.(K) 363/1945, it was hoped in due course to produce the
Berlin and other German "9 cm. " radar on the 8.6 to 8.9 cm.
band in order to aid German night fighters to differentiate
between British and German aircraft.
30. The Korfu Z was to have been ready by mid-summer of 1944
but its advent was delayed by the shortage of magnetrons, all
available specimens of which were required for the ground
Korfu used by the "Y" service. So far as was known the Korfu Z
was never used operationally.
Kiel Z.
31. The Kiel Z was manufactured by Zeiss and known officially
as the FuGe 280. Infra-red radiations from the exhaust stubs
of aircraft were picked up in a parabolic mirror and focused
on to an Elac lead sulphide cell. The field of view in a cone
of ± 10° was scanned. A wider field of view could be obtained
by moving the entire scanner by hand in the same manner as
employed with the Berlin M.1.A.
32. Shortly before the end of the war a number of Kiel Z sets
were tried out in operations but it was found that, although
they gave a range of about 4 km. on a four-engined bomber,
various difficulties arose. Infra-red radiations from the moon
and stars formed "permanent echoes" on the cathode ray tube
used as viewing screen, and were not always easily
distinguished from a moving aircraft. In addition, if the
target aircraft was between the fires caused by the raid and
the night fighter aircraft, the target was obviously quite
indistinguishable against the background of the fires.
33. Night fighters equipped with the Kiel Z were also to
carry the FuGe 218 Neptun R3 backward warning radar so that
they at least had warning of British night fighters
approaching from the rear.
FALTER
34. Falter was an infra-red telescope of the Bildwandler type
used by German night fighters for homing on to British infrared
recognition lamps. Reference to Falter appeared in
A.D.I.(K) 365/1945, paras. 72-76. It was not known if it had
been used operationally.
A.D.I.(K)and S.D. Felkin
U.S. Air Interrogation. Group Captain
2nd August 1945"

[Bruce Dennis]

"SECRET A. D. I. (K) Report No. 599/1944
THE FOLLOWING INFORMATION HAS BEEN OBTAINED FROM P/W AS THE
STATEMENTS HAVE NOT AS YET BEEN VERIFIED, NO MENTION OF THEM
SHOULD BE MADE IN INTELLIGENCE SUMMARIES OF COMMANDS OR LOWER
FORMATIONS, NOR SHOULD THEY BE ACCEPTED UNTIL COMMENTED ON AIR
MINISTRY INTELLIGENCE SUMMARIES OR SPECIAL COMMUNICATIONS.

G.A.F NIGHT FIGHTERS.
R.A.F. BOMBER COMMAND COUNTERMEASURES
AND THEIR INFLUENCE ON GERMAN NIGHT FIGHTER TACTICS.
1. The information contained in this report was obtained from a pilot
and W/T operator of 7/N.J.G.4 and a W/T operator of 5/N.J.G.1 who were
captured after a night operation over Western Germany on October 6th.
2. These are the first prisoners from operational night fighter units
to have been interrogated since the German night fighter force retired
behind its own frontiers, and although none of them had more than seven
operations to call upon for their experience, they were able to provide
a fairly complete picture of tactics now being employed.
3. If these two units can be taken as representative, it is evident
that the German night fighter force, rather than calling the tune in the
interception of R.A.F. night attacks, is now being forced more and more
to improvisation. Its tactics are being governed to an increasing extent
by the effective countermeasures against its Radar and signals system,
and the Germans are quickly reaching a point where they must choose
either a radical change in their methods of interception or continued
improvisation on the present lines.
4. The present report outlines the tactics now being employed by
II/N.J.G.1 and III/N.J.G.4 and shows how, with their signals systems and
interception equipment seriously upset by R.A.F. countermeasures, those
units are groping for a solution to their ever increasing problems of
intercepting the bomber force.
TACTICS OF INTERCEPTION.
Methods Employed.
5. Whilst II/N.J.G.1 is flying free-lance patrol (Ungeführte Zahme
Sau) from the Cologne area III/N.J.G.4, unlike other night fighter units
recently examined favours Geführte Zahme Sau. This method depends on
D.R. navigation by the aircrews, and on simultaneous tracking by the
ground control at Gruppe headquarters, with the addition of a measure of
signals control from the same source.
6. Some of the aircraft of 7/N.J.G.4 are also flying by the old type
of Himmelbett (G.C.I.) control, the system of the night fighter box
controlled by a plotting table, using data from two Würzburgs. On each
night the number of aircraft which may fly by that method - usually two
or three - is announced, and any of the less experienced crews, within
the limits of the permitted number, may do so if they wish.
7. Other forms of control, such as Egon or "Y", are not practised in
the two units under review.
Early Warning and Readiness.
8. Since the night fighters have retired to Germany at least those
units based on the western borders have been robbed of the greater part
of their early warning system, with the result that the aircraft, at
least of the two Gruppen examined, cannot be put into the air at such an
early stage of an impending attack as was previously the case.
9. Recently, therefore, crews have been kept at immediate readiness
night after night from dusk until dawn, whatever the weather. Even when
the nightly met. briefing indicates that flying conditions make night
fighter activity impossible, that state of readiness must continue.
10. In cases where an attack was known to be underway but the probable
course of the bombers had not been established, the night fighters have
in the past been put up and ordered to orbit a given point near the base
airfield, the aircraft being stepped up to 3,000 metres at intervals of
100 metres whilst orbiting. When the point of interception had been
decided upon, the aircraft were given an initial bearing by the Gruppe
commentary.
11. Since the retreat to Germany, there has been little or no orbiting
of the airfield or of beacons by the aircraft of these two units. These
P/W were insistent that no standing patrols are now flown, and that the
night fighters do not take off until warning of an impending attack is
received; occasionally, however, crews are kept in their aircraft at
immediate readiness until the situation has been clarified.
12. Upon receiving the first warning from Divisional Headquarters, the
aircraft have recently been directed immediately on to a bearing to meet
the bomber force. In III/N.J.G.4 at Mainz/Finthen, the whole of the
Gruppe - an average effort of 25 aircraft - is usually airborne within
20 to 24 minutes, the first aircraft taking off within about 8 minutes
of the first corning.
Weather Conditions.
13. The daily briefing of aircraft consists mainly of a summary of
weather conditions for the ensuing night, and when the "Weather Frog"
reports the prevalence of clouds, the main topic is the possibility of
the degree of icing conditions, the worst enemy of the night fighter.
14. In the opinion of P/W, the Germans have never found a satisfactory
de-icing system for the night fighters; the Me.110 is without de-icing
equipment, whilst the Ju.88 is fitted with the "Kärcher Ofen" - a
petrol-burning heater unit - which, however, is not efficient at high
altitudes.
15. If a cloud layer is deep and dense, but without icing conditions,
the night fighters will operate even if the cloud base at their own
airfield is as low as 100 metres; after operations a landing can if
necessary be made at another airfield where conditions are more
favourable.
16. In considering the expedience of operating in icing conditions, the
depth of the ice layer will be taken into consideration; it is possible
that the night fighters may risk climbing steeply through an icing area,
if it is not too thick, to operate at higher and clearer altitudes. If
the bombers are penetrating below a cloud and ice layer, the night
fighters will most certainly be sent up to intercept.
17. In this connection P/W were told of a recent Bomber Command attack
on Essen, when cloud was at 10/10ths between 3,000 and 7,000 metres and
when no German night fighters were put up. Each of these P/W immediately
gave his opinion that the non-appearance of the night fighters was
certainly due solely to icing conditions.
Navigation.
18. During recent weeks when the period of early warning has been
considerably reduced, all crews of a Gruppe are given the same initial
course before taking off; thus, once all aircraft of the Gruppe are
airborne, they are strung out on one and the same track in a form of
line ahead.
19. The crews fly by D.R., and the loose formation is simultaneously
tracked on a map at Gruppe headquarters. If, in the light of the
movements of the bomber force a change of course is necessary, a new
bearing will be given to all aircraft simultaneously through the Gruppe
commentary.
20. All crews are given strict orders to navigate by D.R., and to
accept the Gruppe orders if these differ from their own calculations, so
that the tracker at Gruppe headquarters can be reasonably certain that
the night fighters are in fact where he believes them to be. The older
crews, in spite of this order, are given to "cutting off corners" in the
hope of making a quick interception; in such cases the Gruppe
commentaries is obviously useless, and such crews must thereafter depend
on the Divisional or Reich commentaries and fly free-lance patrol.
21. These crews who stick to their orders are finding D.R. navigation
extremely difficult, since this duty falls on the W/T operator, who has
his signals and Radar duties to attend at the same time. It is therefore
unlikely that the initial formation will be maintained much longer than
the completion of the first leg.
22. If this tactic works according to plan the string of night fighters
should be brought up to the bomber stream on a parallel or nearly
parallel track. At the correct moment, and in accordance with D.R.
tracking at headquarters, the night fighters will be given a new bearing
which turns the whole line on to the bomber stream in a broadside. By
this method at least some of the night fighters must contact the bomber
stream with the aid of their S.N.2 equipment.
23. According to P/W, navigation by the night fighters is at present of
a low standard, particularly in cloudy weather when ground visual aids
are not available. It is evident, however, that the Germans intend to
continue operations on these lines, for in III/N.J.G.4. which is
equipped with the Ju.88, the crew is to be augmented by a Navigator/W/T
Operator, whilst the present W/T Operator will be solely responsible for
the Radar equipment.
24. A few weeks ago several experienced observers from bomber units
arrived at Finthen, and these men are at present being instructed in
night fighting navigation. With the crew of four, the Radar operator
will be placed next to the pilot and the Navigator/W/T Operator will sit
to back to the pilot whist the B/M will sit - or squat - in the
remaining space.
Contacting the Bomber Stream.
25. It is perhaps worth noting that the pilot of III/N.J.G.4., who had
made seven operations, had never succeeded in contacting the bomber
stream, and the Gruppe itself had only claimed one victory since August
8th; that victory was when we attacked Darmstadt or Frankfurt in mid-
September.
26. All P/W agreed that the only way to contact the bomber stream is to
obey the Gruppe commentary until such indications as target markers,
German night fighter flares, Flak and searchlight concentrations or
aircraft going down in flames are seen. Unless the flares are spoof, the
bombers will sooner or later be contacted by these means.
27. According to P/W, crews are wary of flares, as they have learnt
that these may spoof target markers put down to draw unsuspecting night
fighters into a Mosquito trap.
28. Providing that the S.N.2 is not too badly jammed by Window, the
final contact by the night fighter is made by variations of height of
about 1,000 or even 2,000 metres whilst making use of the search gear;
this tactic usually commences at as much as 50 km. from the bomber
formation, in the hope that a straggler may be picked up. Another reason
for this change of height is that in recent raids the heights given by
the commentary have been extremely inaccurate, and the height has
frequently been corrected on suggestions from such night fighter crews
as have made contact with the bombers.
29. The aim in theory is to intercept the bomber stream at its head;
this is the only part of the stream of which the precise position is
given in the commentary and crews do not, therefore, attempt any finesse
regarding the point of entry into the stream. In the words of the
present pilot: "We are damned glad to get into the stream, no matter how
we do it".
30. Lectures are, of course, given to crews on how to avoid Window and
tail warning devices, but P/W pointed out that under present conditions
the theory of the lecture room is extremely difficult to put into
practise, and a hit or miss method of entry is all that can be hoped
for.
Attack.
31. The range at which the night fighter opens fire with its forward
armament is determined by the pilot himself; whilst some will close in
as near as 50/60 metres, the more cautious will open up at a range of
200/250 metres. P/W considered, however, that the normal range might be
taken as l00/150 metres.
32. Recognition of the target aircraft is usually by the silhouette in
light conditions or moonlight, and by the four exhaust flames in
darkness.
33. The present P/W repeated the statement made by previous P/W, namely
that the only effective evasive tactic for a bomber about to be attacked
is a steep diving turn to port or starboard - preferably the latter -
which is on the night fighter pilot's blind side.
34. These P/W could add nothing to previous cements on the Schräge
Musik upward firing armament, but they stated that once this armament
could be brought to bear it was extremely effective; one officer had
claimed a kill with two rounds from the 20 mm. cannon.
35. They stated that the Ju.88 G-1 carried one drum of 50/60 rounds for
each cannon; in that type of aircraft the drums cannot be charged in the
air, but this quantity of ammunition is ample for one sortie.
36. In this connection, P/W had heard that some night fighters are now
being armed with two 30 mm. upward firing cannon in place of the 20 mm.;
with this new armament the barrels protrude 12" to 16" above the
fuselage and at an angle of 85°.
Flak.
37. With two exceptions - orbiting areas and airfields where aircraft
are taking off and landing - there are no restrictions imposed upon the
Flak in any part of Germany. Night fighters which chase a contact
through a Flak area, therefore, do so at some risk to themselves.
38. Old and experienced crews who flew in the days when the use of the
FuGe 25a or Verey signals enabled them to quieten the Flak are unhappy
about present day conditions, but P/W claim that younger crews who have
never known any but these conditions are not particularly perturbed. P/W
added that of course a night fighter would only enter a Flak area if it
already had an S.N.2 contact; no night fighter would venture
unnecessarily in such areas.
39. In orbiting areas, the night fighters will be given a ceiling of,
say, 3,000 metres; any unidentified aircraft above that height will be
fired on in spite of the night fighters below. The Flak units are
usually informed of orbiting areas in advance by the Flak Liaison
Officer attached to the night fighter unit.
40. Flak areas in the neighbourhood of airfields occupied by night
fighters are forbidden to the aircraft when taking off or landing.
I.F.F.
41. For a considerable time there has been a popular belief amongst
night fighter crews that the R.A.F. is homing on to FuGe 25a
transmissions, and crews of II/N.J.G.1 and III/N.J.G.4, including the
present P/W, were no exception.
42. It is difficult to understand how the belief has arisen, since
crews were officially told that the R.A.F. has no equipment with which
to home on to the FuGe 25a, and orders are that the apparatus must be
kept on at all times during flight.
43. In spite of these orders many crews are still switching off their
FuGe 25a during sorties, and when on one occasion one of the present
crews was shot down by Flak, they had the instrument turned off at the
time. At the subsequent enquiry one of the first questions asked
concerned the FuGe 25a, but the crew, fearing punishment, maintained
that it had been switched on all the time.
44. In addition to the fear that R.A.F. aircraft can home on to
FuGe 25a, night fighter crews, including these P/W, have serious doubts
as to its efficiency as an I.F.F. instrument.
45. On one of their earlier operations one of these crews was shot at
by Flak in spite of the FuGe 25a being turned on, and almost immediately
after the W/T operator witched it off the Flak stopped firing. Other
crews in both units have repeatedly been fired on both with the FuGe 25a
on and off, with the result that the majority has come to the conclusion
that as far as the Flak is concerned it does not matter whether the
FuGe 25a is used or not and that it is therefore better to leave it off
and enjoy the added advantage of not being homed at by R.A.F. aircraft.

SIGNALS TRAFFIC.
Gruppe Commentary.
46. The Gruppe commentary of both units reviewed was put out on the
3000/6000 Kc/s. frequency band and was received by the aircraft on the
FuGe 10-P. In III/N.J.G.4 there were usually one main and two
alternative frequencies; until quite recently it was usually found that
the main frequency was not jammed.
47. The W/T operator of I/N.J.G.1 stated that on such occasions as the
Gruppe R/T commentary was jammed he could call his control with the
codeword "Schwingen sie Hammer", whereupon the commentary continued in
Morse on the same frequency; in this way W/T operators could often hear
the Morse Commentary through the jamming.
48. The Gruppe commentary was put out by II/N.J.G.1 from a mobile van
equipped with FuGe 10 and FuGe 16 with the addition, P/W thought, of an
amplifier. The FuGe 16 was however, more often than not u/s, and the
airfield transmitter was used when starting and homing.
49. In III/N.J.G.4 there was also a mobile van, but in P/W’s experience
this was never used and the airfield transmitter was the source of the
commentary put out by that Gruppe.
50. Up to the beginning of October 1944 the two units under review,
although suffering considerable inconvenience from British jamming of
their channels of R/T and W/T control, were able to circumvent the
jamming fairly successfully by the employment of large numbers of
alternative frequencies and differing sources of control.
51. On the night of October 2nd and 3rd, however, the R/T operator of
II/N.J.G.1 found that the whole of the medium frequency band of the
FuGe 10 was jammed, as was the whole of the V.H.F. frequency band. After
some ten minutes of trying to pick up the Gruppe, Divisional and other
commentaries, he switched over to the M/F band and picked up the
commentary on one of the Reichluftflotte beacons.
52. Upon returning from this sortie, this W/T operator found that the
eleven other crews of the Gruppe who had operated on that night had
experienced the same difficulty, and the Gruppe Signals officer
thereupon demanded a written report from each W/T operator.
53. The jamming noise on both the 5000/6000 Kc/s. and the 38.4/42.5
Mc/s. bands was described by P/W as sounding rather like a kettle
boiling, with the lid rattling in a high pitched tone.
54. Instructions in Morse on the 5000/6000 Kc/s. band can be heard
through the jamming when the aircraft is over or near its ground
control, and for this reason III/N.J.G.4, which has only operated
recently within an area of 150 km. of its base at Mainz/Finthen, has not
been troubled to such an extent as II/N.J.G.1, which has been operating
much further afield from its control at Köln/Ostheim.
55. W/T operators of that Gruppe have found the FuGe 16 useless,
because within two or three minutes of the first words being spoken in
an operation, the whole frequency band is jammed; in many aircraft,
therefore, the FuGe 16 as no longer carried as being useless extra
weight.
56. The whole M/F band was also jammed with a high pitched whistle, but
these P/W claimed that they could still hear the Reichluftflotte
beacons. They stated that the latter beacon commentaries were now the
only real source of control left to the night fighters, and that once
these had been effectively jammed, the whole signals system would
completely break down.
Beacon Commentaries.
57. The Reichluftflotte W/T beacons in Central and West Germany – those
with names - only operate, according to P/W, during British night
attacks. These beacons transmit the Reich commentary in Morse in the
following sequence:-
(1) Dash - for D/F’ing
(2) Beacon characteristic.
(3) Letter C - called the Trennung,
separating signal.
(4) Commentary:
(a) A single figure denoting height of head
58. Early in October, W/T operators were told that one of these beacons
in each Jagd Division was to transmit instructions to the aircraft under
its control in a special code, in addition to the normal Reich
commentary. Thus, for example, if a bomber stream were flying towards
Hannover and part of the force detached itself on a southerly course,
Jagd Division 3 would call in the night fighters under its control
through the medium of this beacon to deal with the new situation.
59. In case of all R/T and W/T channels being jammed or otherwise
disturbed, homing instructions to the aircraft were also transmitted
through this medium.
60. The code for these beacons was changed at the same time as the Funk
Befehl (Tactical W/T Code), which on an average was about once a week.
This beacon code consisted of single letters some of which with their
meanings one of the present P/W was able to remember:-
C = Zurückkehren (Return).
B = Fliegen Sie nach 649 (Fly to 649)
649 The code number is that of an airfield.
MOS = Mosquito attack; when aircraft of
631 Ju.88 and ME.110 units hear this,
they return to base, or they may
be ordered to land at the nearest
airfield.
AGZ = Angriffsziel 631 (Target 631). The
number in this case is that of
Darmstadt airfield, meaning that
Darmstadt is the target of the
bombers.
61. Another single letter, which P/W could not remember, signified
"Tune in to frequency of Jagd Division 1". Upon receiving this
instruction, the W/T operators would first try the short wave frequency
of J.D.1 and, if unable to receive the latter, would go over to the
frequency of the high powered beacon of that Division.
62. This contingency would occur when there was no bomber penetration
in the territory of Jagd Division 3, and when an attack was taking place
over the territory of J.D.1. The W/T operators of units of the 3rd
Division would remain tuned in to the last Division beacon until ordered
to revert to their own divisional beacon.
63. In Mosquito attacks when these are recognised as such, no
commentary is broadcast by the beacons.
64. The beacon used for the 3rd Division's code instructions was
Kurfürst, and up to October 6th this beacon had not been disturbed,
neither had its position been moved; P/W had been told, however, that it
was shortly to be moved further East.
65. The beacon Ida has, according to P/W, been moved from its former
position to a point S.S.E. of the visual beacon Ida, and now stands
approximately at pinpoint 50° 30’ N., 7° 45’ E.; the beacon Kuli since
being overrun by Allied advance, has not been replaced.
66. Spoof R/T instructions have a limited success amongst the less
experienced W/T operators, but those operators soon learn by experience
to recognise a strange voice almost immediately; since the complete
jamming of R/T from early October, however, this question hardly arises,
at least in Western Germany.

COUNTERMEASURES AGAINST S.N.2.
Window.
67. The present P/W confirmed the effectiveness of Window countermeasures
against the S.N.2 search equipment. Operators are now being
told that Window is completely effective if the night fighter is at a
range of more than 2,000 metres from a target aircraft; at ranges of
less than 2,000 metres a skilled operator can distinguish between the
Window blips and that of the bomber.
68. The theory is that the night fighter closes in on the Window at a
higher speed than on the bomber, and that the Window blips would
therefore travel quickly down the S.N.2 display, whilst the aircraft
blip would remain more or less stationery. These P/W, however, were of
the opinion that an operator would have to be gifted with a high degree
of skill to be able to follow these suggestions, unless, of course, the
Window cloud was not too dense.
69. They stated that if Window were only thrown by the bombers, it
would be comparatively easy to home on to the Window cloud and thus find
the bomber stream, but since the high-flying Mosquitoes had also taken
to throwing Window the night fighters could no longer depend on finding
the bombers by that method.
70. Thus, in the present circumstances in which Window clouds are
widely spread and do not necessarily indicate the presence of the bomber
stream, it is extremely difficult, if not impossible, to home on to the
bomber stream with S.N.2. alone when Window is present; night fighter
crews are, therefore, depending more and more upon the visual
indications described earlier in this report.
71. One P/W stated that with the S.N.2 jammed by Window, it frequently
happened that a crew would only know that they were in the bomber stream
from the air disturbance caused by the slipstreams of the bombers.
72. The question has been asked whether it is likely that as a result
of jamming of the S.N.2, the Lichtenstein will be re-introduced to the
night fighter units. This has not so far occurred in II/N.J.G.1 and
III/N.J.G.4 and these P/W thought it highly unlikely, since the
Lichtenstein had in the past been just as thoroughly jammed as is the
S.N.2 now.
Electrical Jamming.
73. The Germans are firmly convinced that the R.A.F. is jamming the
S.N.2 electrically. One of the present P/W had himself experienced what
he thought to be such jamming, and had reported this on his return; he
was told that it was caused by a "Rauschsender" (Noise Jammer).
74. The other W/T operator had also been told the same story early this
year, but he then understood that the effect of the jamming on the
display was inconsiderable. In August, this P/W was told officially that
it was possible to home, albeit inaccurately, on to the jammer aircraft
by switching off the S.N.2 transmitter circuit and using the receiver
only.
75. The jamming produced "grass" on both sides of the trace of both the
range and bearing tubes, and he was told that the "grass" extended above
or below and to left or right of the trace, according to the range and
bearing of the jamming aircraft.
76. On the night of October 7th, this P/W experienced a similar display
on the S.N.2, and made an attempt to home on to what he thought to be
the jamming aircraft, but without any result.

MUTUAL INTERFERENCE OF S.N.2's.
77. The S.N.2 of one night fighter will interfere with reception in
another if the two aircrafts are within S.N.2 range of one another. The
disturbance takes the form in the S.N.2 display of continuous wiggling
lines on both height and range tubes; for this reason an eliminator
circuit has been installed, controlled by a knob in the bottom left-hand
corner of the S.N.2. panel, and W/T operators have instructions to make
use of this knob if interference occurs.
78. According to these P/W, it is generally accepted that the
eliminator makes not the slightest difference; neither of these two W/T
operators had themselves used it.
79. It was stated that, providing there are not more than two other
aircraft using the S.N.2 within S.N.2 range of a given night fighter,
the aircraft blip can be read through the disturbance an the display,
but within a range of 2,000 metres, even the interference produced on
the display by one other S.N.2 night fighter is such that the aircraft
blip is extremely difficult to see.
80. As on example of mutual interference, the W/T operator of
II/N.J.G.1 had heard that about two months ago 40 to 50 night fighters
equipped with S.N.2 were sent to intercept some bombers over the Ruhr.
The S.N.2's of the night fighters interfered with one another to such an
extent that not a single contact was made. P/W himself had not taken
part in this operation, but was told about it on the following day.

NAXOS.
A Lecture on Naxos.
81. Early in 1944, one the present P/W attended a lecture given to
I/N.J.G.4 at Florennes by an officer from Werneuchen. The lecture was
accompanied by a film, which showed the development of the Naxos display
as the aircraft closed in on its H2S target.
82. The lecturer claimed to have made the film himself under
operational conditions, and furthermore claimed to have shot down two
H2S aircraft with the sole aid of Naxos; it was emphasised that,
although the aircraft carried S.N.2 in addition to Naxos, the former was
switched off throughout the flight.
83. The film showed the Naxos display initially with two spots of light
when the first contact was made at a range of 70 km. As the Naxos
aircraft closed in, the spots multiplied and spread round the circular
traces of the tube; the circle was completed when the aircraft was
directly below the H2S aircraft and at a range of 50 metres.
84. The lecturer was most enthusiastic as to the possibilities of the
Naxos and foretold that it would displace all other night fighter aids
in attacking H2S aircraft.
85. The type of Naxos shown in the film was the "Z", and the lecturer
mentioned two newer and improved types known as the "Naxos-Post" and
another which P/W had forgotten.
Equipment in I/N.J.G.4.
86. In April 1944, two of the present P/W were at Werneuchen, where for
about a month they carried out flight tests on Ju.88's equipped
variously with Naxos, S.N.2 and Flensburg. Of 20/24 aircraft which P/W
tested in that time, about 16 or 18, equipped with both Naxos and S.N.2,
were delivered to I/N.J.G.4; the aircraft which had no Naxos had both
S.N.2 and Flensburg.
Equipment in II/N.J.G.1 and III/N.J.G.4.
87. It has already been reported that II/N.J.G.1 is equipped throughout
with the Me.110, with the exception of one Ju.88 G-1 in the Gruppenstab;
this latter aircraft was equipped with the Naxos, but had been u/s since
early September.
38. Crews were told that the Me.110 was slow enough without having its
speed further reduced by the Naxos, but they were nevertheless led to
believe that their Gruppe was soon to be equipped with the Ju.88 in
order that Naxos might be employed. Up to the 6th October there was no
sign of the Ju.88's.
89. In III/N.J.G.4 some of the Ju.88's had begun to be sent some weeks
ago to, P/W thought, Werneuchen to have Naxos installed. On October 4th
or 5th, at least one of these aircraft had been returned to Finthen
equipped with Naxos.
Leader Aircraft.
90. When, up to mid-August, II/N.J.G.1 was based at Deelen, the Naxosequipped
aircraft flown by the Gruppenkommandeur was employed as a
shadowing aircraft to home on to H2S transmissions of incoming bombers
and to report their position and composition to the Gruppe.
91. This shadowing aircraft was known as the Führer (Leader), or
sometimes the Aufklärer, (Reconnaissance), and at the first indications
of an R.A.F. attack it took of early - before the remainder of the
Gruppe - and made contact with and flew with the bomber stream.
93. The Division in turn passed such information as was necessary to
the night fighter Gruppen under its control, and this information was
received by the latter on the Tannoy system.
94. When the night fighters took off to intercept the bombers, the
information from the leader aircraft was put out in the form of a Gruppe
commentary; the night fighters could not communicate with the leader
aircraft. P/W did not know if the ordinary commentary was ignored and
all dispositions were made solely on the basis of the shadowing
aircraft's reports, or if other sources of information were used
simultaneously as a basis for the Gruppe commentary; he rather inclined
to the former.
95. Reports by the leader aircraft continued during a raid and included
details such as flares laid, Flak being encountered, and any aircraft
shot down in flames.
96. Once the interception force had been led to the bomber stream with
The help of the leader aircraft, the latter dropped flares of varying
combinations of colours to mark any turning points of the bomber stream,
at the same time informing the Divisional headquarters. The night
fighters were simultaneously ordered by their ground control to fly on
to the flares, or to fly on a specific bearing from these flares.
97. The pilot from III/N.J.G.4 believed that in some units the jammer
aircraft communicate direct with the night fighters under their control,
and issue vectoring orders to them. In all cases however, once the night
fighters have been brought up to the bomber stream, the leader aircraft
is informed by the Division, and thereafter it assumes the function of
an ordinary night fighter.
Night Fighter Flares.
98. These P/W had heard that the Führer aircraft procedure was falling
into disrepute, because on occasions considerable time had been lost
between take-off of the leader aircraft and that of the reminder of the
night fighters, so that in consequence the night fighters had frequently
failed to contact the bombers.
99. This story is perhaps strengthened by thy fact that more recently,
at least in III/N.J.G.4, al1 Ju.88’s have been carrying three or four
flares on each sortie. When a night fighter makes contact with the
bombers, three flares are dropped in or near the bomber stream as a
signal for other night fighters that the bombers have been contacted;
the flares indicate the position of the stream.
100. Until early in October these flares were always composite whitered-
white, each colour burning for one minute in a varying sequence
which was changed from night to night. Just recently, however, crews
have been told that new colour combinations of red, white, yellow and
green would shortly be coming into use.
Single-engined Fighters with Naxos.
101. Whilst at Werneuchen one of these P/W saw Me 109’s and F.W. 190’s –
which they heard were destined for a "Wilde Sau" unit - equipped with
Naxos. In the F.W. 190 the Naxos dome was fixed to the after part of the
sliding part of the cockpit cover. P/W could give no further information
and had not noticed how the aerial array was mounted, but he was certain
that the dome moved back with the cockpit cover.

FLENSBURG.
102. Neither II/N.J.G.1 nor III/N.J.G.4 have any aircraft equipped with
Flensburg, but during the first week of October two new Ju.88 with both
Flensburg and S.N.2 were delivered to the 7th Staffel. P/W did not know
the reason for this delivery, and he had understood that the Flensburg
had fallen out of use.

REACTIONS TO MOSQUITO INCURSIONS.
103. The R.A.F. Mosquito incursions are giving the Germans cause for
some serious thought and, according to P/W, much inconvenience and
disturbance is being caused both by the intruders and the small
attacking forces.
104. Intruders over airfields are, of course, a considerable cause of
disturbance, and it is very seldom that a night fighter crew can land on
its base in peace. Added to this, there is always a sense of uneasiness
amongst crews during sorties, with the result that their efficiency is
much impaired.
105. One of the present P/W - the pilot - went so far as to say that he
would shoot at any twin-engine aircraft without waiting for a
recognition of type, which is strictly against the present rules.
106. The same P/W was of the opinion that at present it is often
impossible for the ground warning system to establish whether a
penetrating force is composed of Mosquitoes or heavy bombers, and that
as a result the night fighters must be put up, if only as a precaution,
until such a time as the true composition and intentions of the force
are established.
107. When a penetration force has been identified as a Mosquito
formation, the Me.110 and Ju.88 night fighters are not put in the air,
and the Reichluftflotte W/T beacons do not transmit a commentary. It was
suggested by P/W, however, that He.219's were being-put up to intercept
Mosquitoes.
108. It has often happened recently that night fighter units have been
put in the air to intercept large four-engined bomber formations which
have only later been identified as smaller Mosquito formations. This has
resulted in much waste of effort, to say nothing of petrol, since the
night fighters were recalled as soon as the attacking force was
identified.
109. In a recent lecture to III/N.J.G.4, crews were told that a small
formation of Mosquitoes could with the help of a special apparatus and a
low speed, lead the Germans to believe that a large formation of fourengined
bombers was underway; crews were given no details of this
special apparatus.
110. It is interesting that of the seven operations which the W/T
operator of II/N.J.G.1 had made, no fewer than three were false calls
caused by Mosquitoes. In these sorties the crews had been sent up to
intercept four-engined aircraft, and after having been airborne for 1 to
11/2 hours they had been called back to base and told that the supposed
heavy bomber force was only a Mosquito formation. The W/T operator of
I/N.J.G.4 had made six operations, and of those two were similarly false
calls for Mosquitoes, on which the night fighters had been recalled
after having been airborne for 3/4 - 1 hour.
111. On one occasion early in October, on the other hand, the aircraft
of II/N.J.G.1, at that time based at Düsseldorf, had been stood down
after an early warning of a "Mosquito penetration". Soon afterwards,
however, cascades of flares were seen falling near the airfield and it
was thought that the airfield itself was about to be attacked.
112. The attack was, in fact, on München/Gladbach, and Oberleutnant LAU
thereupon took off alone at about 2300 hours. That officer shot down two
four-engined bombers and landed again after having been airborne for 22
minutes.
113. The two W/T operators amongst these P/W were sufficiently cooperative
to compile diaries of the sorties which they had made;
although naturally they could not remember dates with any degree of
reliability, their notes include an indication of the inconvenience and
waste of ill-spared fuel of which the Mosquito incursions are the cause.

5/N.J.G.1.
114. (1) On 27th august, 1944. Took off from Deelen at about 2230
hours. This crew was ordered to fly direct to the W/T beacon
Quelle, because, it was said, a bomber force approaching the
Weser estuary from the North Sea was likely to fly to the
Hanover/Brunswick area.
This aircraft, about the fifth to take off from Deelen,
flew for a time on D.R. whilst the W/T operator listened to
the Gruppe commentary. He then switched over to the W/T beacon
and used that commentary.
The pilot made a left-hand turn and at the same time
heard on the beacon commentary that the bombers were heading
for Hannover. By this time, however, petrol was running low
and the crew decided to break off; they landed in Oldenburg.
The S.N.2 was u/s from time of take—off.
This crew only learned afterwards that they had been
directed by the Gruppe commentary to fly to Mannheim, where an
attack was taking place, but since by the time the Mannheim
attack had been identified they had switched over to the
beacon commentary, they had not heard this order to the
Gruppe.
During the afternoon of the day following these raids, an
operations officer of Jagd Division 3, Hauptmann KNICKMEIER,
came to Deelen and gave all the crews a talk on the raid of
the previous night. He told them that the night fighter sortie
had been a failure because as soon as he knew that Bomber
Command were making two penetrations he had ordered all
aircraft of II/N.J.G.1 to break off from the more northerly
penetration and to make for the other bomber stream going for
Mannheim.
This, he stated, had 1ed to some confusion and,
therefore, in the future the night fighters would be allowed
to continue to fly according to their first orders, and no
attempt would be made to divert them to intercept any
subsequent attack.
(2) Early September. Took off from Düsseldorf at 2225 hours.
Objective Stettin - Kiel. Commentary gave false direction of
penetration as Weimar. No interception. Landed at Jüterbog.
(3) Mid-September. Took off from Deelen at 2350 hours.
Mosquito attack. Landed at Deelen after 1/2 hours.
(4) Mid-September. Took off from Deelen about 2300 hours.
Mosquito attack. Landed at Deelen.
(5) End September. Took off from Düsseldorf about 2230 hours.
Mosquito attack. Ordered to W/T beacon Christa. Landed at
Mainz/Finthen. S.N.2 mutual disturbance.
(6) October 2nd or 3rd. Took off from Düsseldorf at about
2230 hours. Heavy bomber penetration with München-Gladbach as
objective. S.N.2 contacts near Münster. Enemy aircraft bombed
through gaps in cloud from 4,200 metres. Commentary gave false
height. Saw four 4-engined aircraft, but could not close in
because they disappeared into cloud. White, red and green
cascade flares. Heavy Flak; several aircraft seen going down.
Landed at Gütersloh after 21/2 hours.
(7) See A.D.I.(K) 365/1944.

7/N.J.G.4.
115. (1) August 7th or 8th. Airborne landings in Seine Estuary.
Took off at about 2300 hours. No contacts; ordered to return
after 11/2 hours.
(2) August 9th. Ordered to W/T beacon Mücke, shot down by own
Flak and bailed out over Nassolt.
(3) End August; Took off from Twente. Mosquito attack.
(4) Mid-September. Took off from Mainz/Finthen at 2300 hours.
Flares at Frankfurt or Darmstadt - apparently Mosquitoes.
Ordered to land after 11/2 hours. No contacts.
(5) About September 20th. Took off at about 2200 hours.
Bombing in Frankfurt area. Saw 4-engined aircraft on opposite
track held by searchlights, but did not go after it as it was
at a greater height. Window upset S.N.2.
(6) October 6th. Took off from Finthen at about 2000 hours
in direction of Kaiserslautern. S.N.2 electrically jammed;
tried to home on jammer without success. Got lost and shot
down by U.S. Flak.

Ground Attack.
116. At the closing stages of the French campaign some of the night
fighter units, including II/N.J.G.1 and III/N.J.G.4, were given the
extra duties of attacking ground targets with their forward armament -
duties which proved both expensive in aircraft and unpopular with the
crews.
117. Since their return to Germany, neither of these two units had
attacked ground targets, but on the night of October 6th an order was
re-introduced into II/N.J.G.1 to attack ground targets if any suitable
objectives were seen.

A.D.I.(K) S.D.Felkin,
2nd November, 1944. Wing Commander."

[Bruce Dennis]

Item 34 onward:


"SECRET A. D. I. (K) Report No. 700/1944
THE FOLLOWING INFORMATION HAS BEEN OBTAINED FROM P/W AS THE
STATEMENTS HAVE NOT AS YET BEEN VERIFIED, NO MENTION OF THEM
SHOULD BE MADE IN INTELLIGENCE SUMMARIES OF COMMANDS OR LOWER
FORMATIONS, NOR SHOULD THEY BE ACCEPTED UNTIL COMMENTED ON AIR
MINISTRY INTELLIGENCE SUMMARIES OR SPECIAL COMMUNICATIONS.
GERMAN NIGHT FIGHTERS.

A REVIEW OF CURRENT GERMAN TACTICS.
1. Three recent A.D.I.(K) Reports, Nos.508, 599 and 620, have
described current German night fighter tactics in some detail and have
shown how the night fighter force, robbed of much of its early warning
and at the same time the victim of extensive radio countermeasures was,
up to the beginning of October 1944, forced into improvisation in its
tactics.
2. This report has been compiled with the object or examining the
extent to which the Germans have varied their tactics during October and
November to meet the continued and successful countermeasures employed
by R.A.F. Bomber Command.
3. The present information has been obtained from a pilot, a radar
operator and a W/T operator of 3/N.J.G.2 shot down in Holland on the
night of November 29th, and from a pilot of the same Staffel shot down
in Belgium on the following night.
4. These prisoners confirm the fact that the situation at the end of
November remained much the same as in early October; the following
paragraphs therefore, whilst adding little to present knowledge of
German tactics, have their value in showing the situation as it was on
the more recent date.
Present Use of SN 2.
5. A re-examination of the conditions under which the night fighters
are operating their search equipment shows that, at least in the
neighbourhood of a bomber stream, interference by jamming is such as to
render the SN2 completely useless. Resort to the alternative frequencies
- of which there are two - had in P/W's experience made not the
slightest difference; he described the disturbance as taking the form of
grass on both sides of the traces on the range and bearing tubes.
6. These P/W expressed the opinion that of late Bomber Command has
been making less use of window in favour of airborne jammers known as
Rausch-Sender (see A.D.I.(K) 599/1944 paras.73 - 76); little
interference from Window has in fact been experienced recently by crews
of I/N.J.G.2.
7. Like their predecessors, the present P/W were not seriously
disturbed by the prospect of Window jamming; recent recommendations had
laid down that under certain conditions the aircraft blip could be
distinguished through the Window disturbances by the difference in their
relative rates of movement down the SN 2 display.
8. In some of the aircraft of I/N.J.G.2 an attempt has been made to
reduce the effects of electrical jamming by mounting the SN 2 aerial
diagonally instead of vertically; these P/W had, however, no first-hand
knowledge as to whether this expedient did or did not improve the
situation.
9. An indication of its lack of success may be that during October the
Gruppe Signals Officer had told the new aircrews that a new version of
SN 2 was in course of development but that meanwhile they would have to
make the best of present conditions and take advantage of periods when
jamming was not present.
10. The Signals Officer did not divulge the name of the new apparatus,
neither did he tell the crews when they could expect it to be introduced
into operations; gossip in the Staffel had it that the new apparatus
would be the SN 3.
11. The Gruppenkommandeur of I/N.J.G.2, Hauptmann RATH, now publicly
claims to have been a life-long adherent of "cat's eye" night fighting
and avers that all his victories have been achieved without the use of
search equipment.
12. It is perhaps worth repeating that, as far as these prisoners knew,
there is no question of re-introducing the Lichtenstein; one P/W, stated
that that apparatus has completely fallen out of use and is not even
employed in training.

SN 2 as Tail Warning.
13. Since the introduction of SN 2 into operations, all prisoners
interrogated have stated that that apparatus in its present form is
capable of giving a tail warning, although at a comparatively shorter
range than its forward capabilities.
14. In I/N.J.G.2 there has recently been a further development in the
improving of the tai1 warning; at the beginning of November new
deliveries of Ju.88 G-6’s began to arrive with an aerial array for tail
warning installed at the extreme end of the aircraft tai1 unit.
15. This array consisted of one dipole carrier similar to those used
for the normal SN 2 forward array, but with the dipoles placed in a
horizontal position.
16. By the end of November, the Gruppe possessed some ten aircraft
equipped in this manner; these P/W had themselves had no experience with
this innovation but had understood that a picture only appeared in one
tube of the SN 2 display - they thought the azimuth tube.
Naxos and H2S.
17. Some time in early October, crews in I/N.J.G.2 began to complain
amongst themselves that something had gone wrong with Naxos; whereas
until that time it had been considered entirely efficient, and they had
always been able to count upon obtaining large numbers of H2S contacts
from a raiding force, they had now begun to obtain so few contacts as to
arouse the suspicion that the R.A.F. had come to known about Naxos and
was playing tricks with it.
18. Up to the end of November, nothing had been said officially by any
of the senior officers, but the opinions of radar and W/T operators may
be summarised as
(a) that H2S is not being used to the same extent as formerly,
(b) that the R.A.F. has an H2S of a new type or with a new frequency,
and
(c) that in some way Naxos is being jammed.
19. Of the 25-30 aircraft it the Gruppe, about half are equipped with
Naxos.

Flensburg.
20. About ten of the aircraft of I/N.J.G.2 are equipped with Flensburg
and according to these prisoners it frequently occurs that Ju.88-G is
delivered with this apparatus installed.
21. Crews are at a loss to understand why the Flensburg is still being
delivered since the apparatus has fallen out of use. At one time
attempts were made to remove the internal part of the equipment to save
weight in the aircraft, but a sharp reprimand came from higher quarters
and it was duly put back. At all events, official instructions on
present intentions with the Flensburg are entirely lacking.
22. It is perhaps worth repeating that the present radar operator P/W
had been told by one of the experienced W/T operators of a possible use
of the Flensburg as a warning of enemy aircraft.
23. It was said that a Monica signal always appeared within two limits
on the Flensburg display; any signal appearing on either side outside
those limits was an indication of either a ground radar pulsation, that
from an SN 2 or from Allied A.I.
24. There was said to be no method of distinguishing between the three
types of signal, but it would be possible to obtain an indication of
whether a transmission originated from below, above or at the same
level. In this way, it was claimed, Flensburg at least gave an
indication that another aircraft, possibly a Mosquito using A.I., was in
the vicinity.
25. One of the present crews had Flensburg installed in their aircraft
but they had never taken an opportunity to try out the recipe described
above.

SIGNALS TRAFFIC.
German Reaction to Continued Countermeasures.
26. The fact that at the beginning of October the German night fighter
force was reduced to only one reliable signals channel - the high
powered W/T beacon commentaries - was reported in A.D.I.(K) 599/1944
para.46 et seq. The present interrogations, whilst producing little that
is new, have once again confirmed that the situation with night fighter
signals was as previously reported and, in fact, remained little changed
at the end of November.
27. In I/N.J.G.2 the W/T operators had been experiencing exactly the
same difficulties as in the other units recently examined; the present
P/W stated that they too had found the Divisional and Gruppe
commentaries on the M/F and H/F bands seriously jammed from about the
middle of September, and they too had been forced to resort to the
Divisional commentary put out by the high-powered W/T beacons.
28. On rare occasions, it has been possible to hear the Gruppe morse
commentary (Gruppen Tastführung) through the jamming but results are in
the majority of cases so uncertain that operators waste no time and go
straight over to the beacon commentaries; the latter present no
difficulties.
29. These P/W described the jamming note on the Fu.Ge.10P frequencies
as being a rising and falling whistle. The VHF frequency band of 38.4 -
42.5 Mc/s has fallen completely out of use for the purposes of
commentaries, but in the FuGe.16 was still used at take-off and for
landing at the base of the unit at Kassel.
30. Thus, the present situation is that the night fighter Gruppen can
no longer operate as units, but each individual crew must judge the
situation for themselves from the information given by the beacon
commentary and must themselves decide whether they shall attempt to
intercept the bombers or give up the chase; if the search equipment is
jammed, and the homing equipment produces no reactions, then the night
fighter operation is reduced to the level of a Wilde Sau sortie.
31. One further complication which arises when the Gruppe commentary is
inaudible is that crews listening to the Divisional commentary from the
high-powered beacons often miss orders given to aircraft of the Gruppe,
with the result that recall orders are frequently not heard and much
effort is wasted in aircraft flying about aimlessly.
32. Eventually, when the attack is over and jamming has been withdrawn,
crews will return to the Gruppe frequency and then belatedly hear the
orders to return to base.
33. It is perhaps worth adding that the aircraft of I/N.J.G.2 have not
been flying by the Himmelbett (Würzburg-Freya controlled) method.

RECONNAISSANCE AND LEADER AIRCRAFT.
Definition.
34. The prisoners were able to clarify the question of the so-called
formation leader (Verbandsführer) described somewhat inadequately by
previous P/W and reported in A.D.I.(K) 599/1944 paras.90-97.
35. It transpires that two separate categories of aircraft with totally
differing functions are employed; one, known as the Aufklärer
(Reconnaissance) has the duty of taking off before the main formation
and of contacting and reporting on the composition and movements of the
bomber stream.
36. The other aircraft, the Verbandsführer, is the leader of a night
fighter formation and, in an attempt to keep the unit together, that
aircraft transmits periodical D/F signals, on to which the others are
supposed to home, and which in theory have the effect of keeping the
formation together.
37. Neither system has recently been working satisfactorily, largely
owing to the jamming of signals channels. Nevertheless, in I/N.J.G.2
nightly preparations were made for putting reconnaissance and leader
aircraft up, should Divisional Headquarters decide that it was
necessary.
38. The functions of these two aircraft described in turn below.
Verbandsführer (Formation Leader).
39. The Verbandsführer aircraft it normally flown by an experienced
senior officer such as the Kommandeur or a Staffelkapitän, and his
aircraft always takes off with the main force of the Gruppe.
40. When ordered to take off, the aircraft of the Gruppe fly an initial
course in the normal manner. Thereafter the duty of the Verbandsführer
is to transmit a periodical D/F signal of two minutes duration at 10, 15
or 20 minute intervals, together with a pre-arranged single code-letter;
the aircraft of the formation are expected to home on these signals and
thus maintain a compact formation.
41. The code letter and the exact times at which the D/F signals shall
be transmitted are arranged at nightly briefings.
42. In I/N.J.G.2 the D/F signals were given on the long wave band of
the FuGe.10, with the addition of short-wave R/T or W/T instructions by
the Verbandsführer to the formation on changes of course and height;
only the leader aircraft was permitted to transmit.
43. The leader aircraft supplemented the R/T orders by the firing of
prearranged verey signals as a guide to the bomber stream.
44. The Verbandsführer system had one serious disadvantage in that the
D/F signals when given at the longer intervals, had the effect rather
of scattering the formation after the first leg of a course from base,
since the aircraft of the formation were apt to zig-zag across the
leader's track at each succeeding D/F signal.
45. Up to the middle of September the Verbandsführer procedure could be
said to be operating fairly satisfactorily, but when jamming of the
frequency bands of the FuGe.10 commenced, its operation became
impossible and in I/N.J.G.2 the procedure was dropped.
46. Divisional orders to operate a Verbandsführer still stand, and a
routine daily briefing on procedure and callsigns was still held with
I/N.J.G.2; Hauptman RATH, the Kommandeur, openly admits, however, that,
under present conditions he has no intention of operating a
Verbandsführer and by holding the briefing he is merely obeying
Divisional orders in the spirit.

Reconnaissance (Aufklärer aircraft).
47. The duty of the Aufklärer aircraft is to make contact with the
bomber stream with the help of ground control, Naxos and SN 2, and then
to report directly and solely to Divisional headquarters on its
composition and movements. The Aufklärer is usually one of a number
detailed daily from the ordinary night fighter Units.
48. In I/N.J.G.2 the crews of from one to three aircraft equipped with
Naxos were briefed nightly to stand by for Aufklärer duties; orders to
take off came from the Division, and once airborne the aircraft operated
entirely under Divisional control on a special frequency known as the
Aufklärer Welle.
49. Once the Aufklärer had served its purpose of contacting and
reporting on the raiding force, that aircraft, on orders from the
Division, assumed the duties of a normal night fighter.
50. It usually happened that orders to the Aufklärer to take off
preceded those to the main force by anything from ten minutes to one
hour; the Aufklärer detailed in I/N.J.G.2 were sometimes ordered up
singly, whilst at other times two or three took off together. If no
orders came from Division, then the Aufklärer took off with the main
force and operated as normal night fighter.
51. Since the beginning of October, the Aufklärer aircraft, although
briefed and standing by nightly, had not been ordered up by Division.
These P/W were of the opinion that of late the channels of “Y” control
had been so seriously disturbed as to make the procedure impossible in
Western Germany. Additionally the air situation had recently been so
confused that nothing more could be done than to order the main force of
night fighters to take off at the last moment - and very often too late
to be of any use.

TACTICS OF INTERCEPTION.
52. The following paragraphs of necessity take the form of notes and
additions to the account given in A.D.I.(K) 599/1944. The methods used
in I/N.J.G.2 have been found to follow the same principle as those used
by other units; the present P/W were, however, able to clarify several
points and to enlarge upon others.
Readiness.
53. Standing patrols were not flown by I//N.J.G.2; as with other units
examined recently, a met and signals briefing was held each evening and
crews remained at readiness in the crew-room during the whole of the
night or until such a time as they were called on the Tannoy laid on in
the room.
54. The aircraft were lined up at a dispersal and the engines were only
started up after a crew or crews had been called to take off. In this
case the first aircraft could be away within 8 minutes of the crew being
called; it had occasionally happened that crews were detailed to sit in
the aircraft, but with the engines still.
55. Should an order to take off prove to be a false alarm and the
aircraft be ordered to return, crews resumed their original state of
readiness and the fuel tanks of the aircraft which had returned were
immediately topped up ready for another start.
56. In the case of double sorties being flown, crews who returned to
their base airfield after the first sortie resumed their original state
of readiness. Such aircraft as landed on other night fighter bases,
however, were temporarily attached to the unit which they visited, and
received signals briefing as though they belonged to that unit.
Take-off.
57. There is no predetermined point at which the night fighters are put
up to meet a raiding force, and sources of early warning of bomber
penetration are, of course, unknown to the majority of operational
crews.
58. In the experience of these prisoners, the order to take off was
occasionally accompanied by a note as to the position and direction of
the bomber force, but often, as on the last sortie of the 4R + RL on the
night of November 29th, the night fighters were simply ordered to make
for a given high powered W/T beacon and to await further orders.
59. In the days before the Gruppe commentary was jammed, the aircraft
were went to assemble over or near their base airfield, after which
orders were given as to course and height to meet the bombers. Under
present conditions, each crew or batch of crews ordered into the air is
given an initial course which takes them to a beacon, or which is
calculated to bring them directly to the bomber stream. If, after the
first leg, no contact is made, the crews must do the best they can from
the beacon commentary.

Navigation.
60. Navigation in I/N.J.G.2 follows the general practice amongst German
night fighters in that an attempt is made to navigate primarily by D.R.
with the additional help of ground navigational aids; it was stated that
at present the only reliable aids were the visual and radio beacons.
61. One of the present P/W had the idea that some aircraft of the
Gruppe, including those of the Kommandeur and Staffelkapitäne, were
using Bernhardine as an additional aid, but he could give no further
details. He had understood that the method of determining a position was
by means of a succession of sine curves along a horizontal base, with a
series of figures at the points where the curves struck the base line.
Contacting the Bombers.
62. These prisoners repeated that no attempt is or can be made to
operate in any specific part of the bomber stream, and under present
conditions crews are content to have found the bombers at all, no matter
how or where.
63. Once in the stream the night fighter crew will attempt to remain
there, and it is only if chased off by a Mosquito or through lack of
fuel or other defects to the aircraft, that the pilot wi11 deliberately
leave the stream again.
64. The commentaries are broken off as soon as an R.A.F attack has
finished - at least as far as the recent shallow penetrations have been
concerned – and the question as to whether the returning bomber shall be
followed on their homeward track lies entirely with the night fighter
crews, and depends largely upon the amount of fuel remaining in the
aircraft.
65. There are no restrictions as to how far beyond the German border
the night fighters shall fly, but these P/W pointed out that after the
bomber attack is over, the night fighter has no commentary to help him.

I.F.F.
66. At the beginning of November the Signals Officer at I/N.J.G.2
announced that the R.A.F. had equipment for homing on to FuGe.25a
transmissions; he nevertheless told crews that the order to keep the
I.F.F. switched on must stand, but he added the order that the apparatus
should be turned off when leaving German territory.

Armament - German and R.A.F.
67. The rear armament of one M.G.131 in the Ju.88 G-6 is intended
solely for defensive purposes. The majority of crews felt that this
armament was an unnecessary extra weight, and these P/W themselves had never heard of a case where it had been used in combat.
68. As far as R.A.F. armament is concerned, crews in I/N.J.G.2 at least
have no knowledge of the use of radar aids by R.A.F. gunners. These P/W
stated, however, that tracer fire from a bomber has distinct deterrent
effect upon all but the most hardened night fighter crews.

Petrol.
69. There has been no noticeable shortage of petrol in I/N.J.G.2 and
according to these P/W there have been no orders to economise. The sole
indication of any shortage was a recent restriction in SN 2 practice
flights by day.

Night Rocket Phenomena.
70. The question has been asked as to whether the Germans are using jet
propelled aircraft at night. These prisoners had not heard of the use of
this type of aircraft and were inclined to ridicule the suggestion.
71. They themselves had seen rocket traces at night and had attributed
these to rocket Flak; they had had to draw their own conclusions,
however, since officially they were told nothing.
72. One of the present pilots had twice encountered enormous flaming
masses over Berlin some time ago; he had at first thought these to be
aircraft going down in flames, but on the second occasion he was close
enough to make a careful observation and could see that the rate of fall
was too slow for a crashing aircraft. Again, he had been told nothing
officially.

THE NIGHT FIGHTER'S DIET.
73. The fact that night fighter crews must now depend more and more
upon good night vision has prompted an enquiry into the measures being
taken by means of diet and drugs to maintain a standard of night vision
in I/N.J.G.2.
74. The familiar black pills formerly distributed to night fighter and
bomber crews in the G.A.F. were absent in this unit. The normal diet of
the night fighter was given by one of the present P/W as follows:-
Breakfast: 30 grammes of butter,
White bread,
One egg,
50 grammes of sausage,
½ litre of fresh milk,
Ersatz coffee.
Lunch: Soup; varying from meat and vegetable to
noodle.
Meat and 2 veg.,
Pudding (occasionally}.
Supper: 45 grammes of butter,
80 grammes of sausage,
Black bread,
Jam or artificial honey,
8 cigarettes
75. When returning from a sortie, the night fighter is given the
following special issue:-
25 grammes of chocolate,
25 grammes of coffee beans (real),
2 packets of boiled sweets,
1 cake of dried fruit,
Biscuits.
A.D.I.(K). and U.S. S.D. FELKIN
Air Interrogation. WING commander
30th December 1944"

[Nick Beale]

Originally Posted by Marcel van Heijkop

Absolutely! Count me in, Nick!

PS: Is your website down at the moment? I tried to read the info from the links you provided, but couldn't get on your site.

Best regards,

Marcel

Hi Marcel,
My website is still alive (I just checked) and both those links work for me.

Another site with a selection of transcribed ADI(K) reports is: http://www.cdvandt.org/felkin_reports.htm. The emphasis there is on radar and communications systems.

[Bruce Dennis]

"SECRET A. D. I. (K) Report No. 125/1945
THE FOLLOWING INFORMATION HAS BEEN OBTAINED FROM P/W
AS THE STATEMENTS HAVE NOT AS YET BEEN VERIFIED, NO
MENTION OF THEM SHOULD BE MADE IN INTELLIGENCE
SUMMARIES OF COMMANDS OR LOWER FORMATIONS, NOR SHOULD
THEY BE ACCEPTED UNTIL COMMENTED ON AIR MINISTRY
INTELLIGENCE SUMMARIES OR SPECIAL COMMUNICATIONS.

G.A.F.NIGHT FIGHTERS.
RECENT DEVELOPMENTS IN GERMAN NIGHT FIGHTING.
1. Between the opening of the Rundstedt offensive on 17
December 1944 and the night of 1st January 1945, fifty-nine
German night fighter aircrew captured on the Western Front
were brought to England for interrogation by A.D.I.(K). Of
these prisoners, ten were selected as being suitable for
special interrogation with the object of investigating current
German tactics, and the extent of their deviation from methods
employed up to the end of November and reported in A.D.I.(K)
508, 599, 620 and 700/1944.
2. The present report is based on the interrogation of these
ten prisoners, who came from III/N.J.G.1, II and III/N.J.G.2
and II, III and IV/N.J.G.3, and of whom one had recently spent
some time at the G.A.F. radar experimental station at
Werneuchen. In addition, there was one prisoner who had spent
one year as a ground radar mechanic with I/N.J.G.4 and had
then transferred to the Schulstaffel of the same unit to train
as a radar operator. The Schulstaffel had been dissolved at
the end of October 1944 and its personnel posted to the
infantry; this P/W fell into Allied hands as an unwilling
member of the Waffen SS.
3. From interrogation of previous night fighter prisoners -
captured between September and the end of November 1944 - it
has been amply proved that the German night fighter force has
been at a loss to overcome the successful Bomber Command
spoofery and radio countermeasures and as yet has made no
progress in its efforts to overcome this disadvantage.
4. From the present interrogations there are signs that the
Germans, not content to let the matter rest as it is, are
striving to gain the upper hand over Bomber Command by the
introduction of at least two new measures. One of these,
discussed in the following paragraphs, is the employment of
Bernhardine beacons for the dual purpose commentary and
navigation, and the other - as yet in its early stages - the
probable introduction of a new type of search equipment, the
SN 3. Details of the latter are at present lacking, but
evidence suggests that it may be of the nature of centimetre
A.I.

BERNHARDINE – FuGe.120.
Earlier Vicissitudes.
5. As far as G.A.F. prisoners are concerned, Bernhardine is
no innovation, as early as May 1942 hazy allusions to this
form of navigational aid were made by prisoners, but the first
mention of Bernhardine by name was made by an officer of
1(F)/121 captured in October 1943 (A.D.I.(K) 498/1943;
thereafter nothing further was heard until K.G.66 opened its
pathfinder operations over England early in 1944.
6. A prisoner from 5/K.G.66 captured in England on 25th March
1944 gave an account of Bernhardine which, in the light of the
present interrogation proves to have been remarkably accurate
(A.D.I.(K) 187/1944, paras.19 – 24)
7. In October 1943, 5/K.G.66 had had 1 Do.217-M equipped with
Bernhardine, but after some experiments the experts had come
to the conclusion that the apparatus was not sufficiently
accurate for pathfinder operations; the P/W concerned had
heard later that work on the ground installations had ceased.
8. In spite of continued interrogation of subsequent
prisoners, nothing more was heard of Bernhardine until late in
December 1944. The capture of a prisoner from III/N.J.G.1 on
17th December 1944 and other prisoners from II and III/N.J.G.3
later in the same month has now revealed that Bernhardine is
being seriously considered - if not already used - not only as
an aid to night fighter navigation but as a source of the
commentaries.
Introduction of Bernhardine to Night Fighting.
9. Some time in October 1944, crews of 8/N.J.G.1 were given a
preliminary lecture on Bernhardine in which its principles
were explained, they were told that it was no new discovery
but would shortly be introduced to night fighting. In
III/N.J.G.3 crews had also been given frequent lectures and by
November some of the aircraft of that Gruppe already had the
necessary apparatus installed.
10. According to prisoners who attended these lectures, the
transmissions from the ground station take the form of a
conventional twin lobe polar diagram with an equisignal area
and with a very small amount of rearward radiation. A signal
transmitted from the ground station once every minute is
translated by the airborne apparatus into a teleprint message
on a paper tape giving the QTE (true bearing) of the aircraft
from the ground transmitter followed by a further image in
figures and letters which is a Divisional commentary of the
type at present broadcast by the high powered W/T beacons.
11. It was explained that the Bernhardine transmitters would
operate on 32 frequencies between 30.0 and 33.1 mc/s, and that
the signal would be received through the normal E.Bl.3 in the
aircraft. Thus the first 32 of the 34 spot frequencies of the
E.Bl.3 would be used for Bernhardine whilst the remaining two,
33.2 and 33.3 mc/s, would be retained for blind landing
purposes.
12. It is claimed by P/W that Bernhardine signals are
unjammable and that transmissions have a range of 400 - 500
kilometres.
13. A captured night fighter map, recovered from a recent
crash in Belgium and issued by the signals officer of N.J.G.3,
was marked with Bernhardine transmitters at approximately the
following pinpoints;-
N° 0(?) Berlin 52°13'N;13°6'E
N° 8 Alkmaar, Holland. 52°42'N;4°38'E
N° 9(?) Leck 54°41'N;9° 2'E
N° 10 Thisted, Denmark. 56°42'N;8°33’E
N° 11 Breslau 51°25'N;17°5’E
N° 12 Pilsen 49°45'N;13°15’E
14. A further indication that Bernhardine may already be in
operational use was found in a file of signals orders from an
aircraft of II/N.J.G.1 shot down on December 31st. On the same
page as the usual numbering of the Y-line frequencies was
another column headed "Kanäle" (= channels); the channels were
numbered from 1 to 32 and to each number was appended a
frequency, commencing with 30.0 at No.1 and rising by .1 mc.
to 33.1 mc/s at No.32.
15. Both of the above documents have been forwarded to
A.I.4(b).

Airborne Apparatus.
16. The Bernhardine apparatus in the aircraft is contained in
a box measuring some 60 cm in width, 30 cm in height and 20 cm
in depth, placed in the JU.88 in some cases to the right of
the W/T operator on the lower port wall of the fuselage and in
others to the left of the W/T operator or in the forward
instrument panel.
17. The front of the box has a wide glass-covered slot about
40 cm. in length and 12 cm. in depth along which the paper
tape travels from right to left after the necessary data have
been printed upon it by a teleprinter contained in the box.
The on-off switch for the apparatus, marked FuGe.120, is
placed on the R/T operator's switch panel, and is used in
conjunction with the click-stop frequency selector for the
E.Bl.3.
18. From evidence supplied by the present P/W it is possible
to give a description of the Bernhardine display and of the
exact data which it supplies. An impression of the Bernhardine
display is given below; it will be seen that the printed tape
is divided into three horizontal sections, on the uppermost of
which appears a series of close vertical lines shortening at
intervals to a "V", on the central section a reading in
degrees, and on the lower a coded image which is the
commentary. One simultaneous printing of these sections takes
place during ten seconds of every minute, the tape remaining
stationary for the remaining fifty seconds, after which the
process is repeated.
19. In the lectures on Bernhardine it was stated that the
ground transmitter makes one full revolution of 360° in sixty
seconds; a section of the pattern of the ground transmission
is repeated on the tape in the form of the series of vertical
lines, the equisignal zone being represented by the apex of
the "V".
20. In each printing lasting ten seconds a sector of 60°
appears on the tape and in every case it contains a repetition
of the equisignal zone. The reading in degrees appears in the
central section of the tape in numbers representing 10's of
degrees, and the point opposite to which the apex of the "V"
is printed represents the bearing in degrees of the aircraft
from the transmitter. Accuracy of bearings was stated to be
within 0.5°.
21. A recognition letter is allotted to each transmitter and
is repeated on the tape at every 20° on the scale; in the
sketch the letter X - the recognition for the Leck transmitter
is shown.
22. The commentary in the lowest section appears in each 10-
second printing as a group of a maximum of ten letters and
numerals, inclusive of two crosses denoting the beginning and
end of a message. Should a message be of more than ten
characters it wi11 be continued in the succeeding printing, a
cross appearing at the end of the message.
23. Thus, the commentary message shown in the sketch, + 40 KA
27 100, just falls within the ten-character limit if the final
+ denoting the end of the message is omitted. The latter is
therefore carried forward and appears at the commencement of
the next printing; it denotes simultaneously the end of the
one message and the beginning of the next. It was stated that
a single message could be continued over three or four
printings.
24. The commentary always appears in a standard order;
analysis of the typical message shown in the sketch is as
follows:-
25. It will be noted that the form of this commentary is
exactly the same as that at present put out by the Divisions
on the high powered W/T beacons (see A.D.I.(K) 599/1944 para.
57).
26. The present P/W had been told that, in addition to the
Divisional commentary, instructions to individual formations
of night fighters would be transmitted by the Bernhardine and
printed on the lowest section of the tape. How, in such a
case, the aircraft would be tracked or how the orders by the
subordinate units would be coded, they did not know.

Operational Use.
27. The aircraft set is switched on soon after take-off, so
that the bearing transmitter can be constantly watched. If the
+ = beginning of message
40 = height of head of bomber stream in 100’s of metres
KA = fighter-grid position of head of stream
27 = course of formation in tens of degrees
100 = estimated number of aircraft
W/T operator wants the fix, he switches over to the
transmission of a second Bernhardine station for a gross
bearing; it was stated, however, that quicker and more
favoured method was to obtain a simultaneous cross bearing
from a high powered beacon through the PeilGe 6.
28. As far as these prisoners knew, only the Bernhardine
stations at Berlin and Leck are so far capable of transmitting
a commentary and flying instructions; the latter station was
only modified in this way at the beginning of November 1944
and aircraft of 9/N.J.G.3 made several test flights, usually
taking off from Uetersen at about 0230 hours and remaining
airborne for some four hours.
29. The present P/W of 9/N.J.G.3 had not taken part in these
flights, but after the tests he had seen the tape, which he
described as being printed on white paper in red letter,
4 - 6 mm. high as clearly as with a typewriter. He was told
that there was sufficient tape to allow of continuous
operation for 4 hours 20 minutes.

SIGNALS TRAFFIC.
German Spoof Signals.
30. An aircraft of 7/N.J.G.3 shot down in Belgium on January
1st carried a signal order on which appeared the word
"Orgelpfeife" (= organ pipe). Interrogation of all the present
P/W elicited the fact that Orgelpfeife is the codeword for
spoof R/T and W/T traffic passed between small numbers of
aircraft and the ground with the object of simulating large
numbers of night fighters in operation.
31. According to a P/W of 9/N.J.G.2 Orgelpfeife was
introduced in that unit, in mid-November; one crew in the
Staffel had received special briefing and usually operated the
spoof traffic. In operating R/T spoof, this crew’s duty was to
imitate a large number of night fighters operating by the
simple expedient of all four members of the crew taking turns
to speak, each using different callsigns.
32. It was said that the pilot of the crew in question,
Oberfeldwebel GELLNER was something of an actor and was able
to imitate various German dialects and different voices; P/W
claimed that the single Aircraft could simulate as many as
twelve night fighters.
33. The Orgelpfeife aircraft operated under Y control, since
such importance was attached to its position in relation to
the raiding force; the spoof aircraft patrolled an area near
the estimated target and as the raiding force was approaching
the target, the simulation of night fighters operating
commenced.
34. According to P/W the spoof aircraft carried large
quantities of Düppel (Window).
35. It seems that only one aircraft in a Staffel operates
Orgelpfeife; this was certainly the case in III/N.J.G.2, and
another P/W of III/N.J.G.3 stated that similar conditions
prevailed in that Gruppe.
36. None of the present P/W could give any useful information
on the method of coding the Orgelpfeife traffic, but it was
stated that the briefing usually gave two codewords or groups,
according to whether the spoof was R/T or W/T, and the crew
was to ignore all orders from the ground except those preceded
by the operative Orgelpfeife codewords or group.
37. In the captured briefing sheet mentioned above, the
codewords for 7/N.J.G.3 on the night of December 31st were
"Elfenbein" for the aircraft and "Hallore" for the ground.
38. A P/W of 9/N.J.G.3 stated that early in December R/T
silence had been enforced amongst the normally operating night
fighters of that Staffel.

Defence of the Ruhr by N.J.G.1.
39. The four Gruppen of N.J.G.1 have been allotted the
special task of defending the Ruhr in night attacks by R.A.F.
Bomber Command, and to achieve this aim all the Gruppen are
based strategically at airfields in that area.
40. In operations over the Ruhr the Gruppen are not
controlled separately as would normally be the case, but
operate under the central control of a special Geschwader
commentary put out on a M/F and an alternative V.H.F.
frequency; the latter, however, is almost invariably jammed.
41. This commentary consists of tactical instructions to the
aircraft as well as reports on the general situation;
according to P/W, the latter are not based on a Divisional
picture of events, but on data supplied by the Ruhr Flak
defences.
42. When a Mosquito force is reported over the Ruhr area, and
providing that flying conditions are suitable, all aircraft of
N.J.G.1 are put up and ordered to orbit any of the beacons
Börse, Bruno, Achmed, Gemse, Heide, Schnake, Paule, Ratte and
Drossel to await further events.
43. In case of jamming of both channels of Geschwader
control, two of these beacons, Achmed and Paule, are set aside
for transmission of the Geschwader commentary. P/W also heard
that a further alternative H.F commentary is to be put out on
a 20 kW transmitter whose signals will be superimposed on a
Cologne broadcast programme.
44. The aircraft of N.J.G.1 usually orbit the beacons for
about an hour, and if by then no attack by four-engined
bombers has materialised they are recalled; upon returning to
base, the aircraft are immediately refuelled so that should a
further attack be made a fresh sortie can be initiated
immediately.
45. In the middle of December some 50% of the aircraft in
N.J.G.1 were equipped with two white LC.50 flares carried
externally under the outer rings, and in the event of a major
bombing attack on a Ruhr objective these aircraft were to make
for the target and lay the flares at the operative height of
the bombers, so that the remainder of the night fighters could
quickly close in the area for visual attack.
46. The flare-carrying aircraft were to be given an X-time
for arrival over the target to coincide with the arrival of
the bomber stream; at this time the Flak would have orders to
cease fire, the flares would be laid and the night fighters
would go in to attack.
47. Importance was attached to the flare-carrying aircraft
arriving exactly at X-time, since a previous arrival would put
them and the remainder of the night fighters in danger of
being shot down by the Flak, and a late arrival would
jeopardise the operation.
48. In such a case where the aircraft of N.J.G.1 had been put
up against a spoof attack of Mosquitos and a four-engined
attack developed against targets outside the Ruhr, the
Geschwader commentary would transmit the codeword "Diogenes",
at which the aircraft would revert to their respective Gruppe
commentaries and would operate against the new attack in the
normal manner.
49. Crews of the flare-carrying aircraft were instructed that
in defending targets outside the Ruhr they could use their
flares, but only if they were certain of the true target.
Jamming of Commentaries.
50. Prisoners of II and III/N.J.G.3 stated that the Gruppe
commentaries were not seriously jammed in the Hamburg area;
although R/T could occasionally be heard, however, crews
relied mostly on the morse commentaries.
51. They stated that intensity of jamming varied considerably
from night to night. They could not understand the reason for
this since they had been officially told that the jamming had
been D/F’d and traced to the London area.
Verbandsführer (Formation Leader).
52. From the present P/W there are again conflicting reports
on the success or failure of the system of flying in formation
with a leader aircraft (A.D.I.(K) 700/1944, paras.34 – 49).
53. Whilst one P/W of N.J.G.3 stated that the system had been
working well in that Gruppe up to mid-December and that leader
aircraft operated under Y control, another prisoner, of
8/N.J.G.1, stated that in his unit the system had proved
unworkable and had been dropped in October. He gave as one
reason the dislike by the more experienced crews who flew as
formation leaders of acting as flying beacons, with the
attendant danger of being homed on by Mosquitoes.

I.F.F.
54. Much has already been said about the FuGe.25a in recent
A.D.I.(K) reports but nevertheless interrogation has continued
as to the conditions under which the apparatus is or is not
switched on during operations. One P/W of 8/N.J.G.1, based at
Düsseldorf, stated that if no intruders were reported at the
time the night fighters were ordered up for an operation, he
would switch on the FuGe.25a at take-off and keep it operating
until well clear of the airfield.
55. During operations he would have the instrument turned
off, but on returning to base would again switch it on shortly
before reaching the airfield - provided no warning of
intruders was in force.
56. A P/W of 9/N.J.G.3 knew of the British air-to-air I.F.F.
and knew that R.A.F. A.I. included a button which, upon being
pressed, identified the friendly aircraft on the A.I. picture.
57. Crews in this Staffel were told that a German air-to-air
I.F.F. was shortly coming into operation, but no further
details were given.
58. A prisoner of 11/N.J.G.3 remembered having seen a note in
a G.A.F. intelligence summary stating that the R.A.F. was
using infra red air-to-air recognition.

Hermine Beacons.
59. One of the present P/W had first heard of Hermine V.H.F.
beacons in March 1944, and at the time had learned that these
were radio beacons of new type from which pilots of singleengined
aircraft could obtain bearings.
60. He stated that the beacon, which has an effective range
of 200 – 300 kilometres, rotates through 360° in about three
minutes. The beacon transmits a continuous tone over about
359° with a silence zone of 1° which sweeps through 360° as
the beacon rotates; additionally a "speaking clock" counts
continuously from 1 to 360 and the continuous tone is
superimposed over this speech.
61. The pilot in the aircraft hears the continuous tone and
the counting on the FuGe.16Z, but hears the bearing spoken
clearly when in a line with the silence zone; he thus hears
his bearing to the beacon.
62. It will be remembered that prisoners of the Wilde Sau
single-engined night fighter unit I/J.G.301, captured in July
1944, had made mention of these radio beacons, albeit not by
name. The Kommodore of a single-engined day fighter Geschwader
had suggested that "Hermine" is derived from Oberst HERMANN,
founder of Wilde Sau night fighting.

INTERCEPTION EQUIPMENT.
Spot frequencies of SN.2.
63. The word "Streuwelle" in conjunction with SN 2 has been
mentioned for the first time by the present batch of
prisoners. Although none was able to define the word
Streuwelle or its origins, one suggested an alternative word
"Frequenz"; A.D.I.(Sc.) has supplied an agreed translation of
"Streuwelle" in the term "Spot frequency".
64. It has already been reported that in I/N.J.G.2 an attempt
had been made to reduce the effects of electrical jamming by
mounting the SN 2 aerial arrays diagonally instead of
vertically. These prisoners confirmed that this had also been
the case in other units, but the present interrogations have
established that this arrangement of aerials has no connection
with the spot frequency of the SN 2. In many cases prisoners
have known the differing aerial arrangements to exist in
several aircraft all equipped with SN 2's of the same spot
frequency.
65. These prisoners knew of three Streuwellen at present in
operational use, namely 4, 5 and 6; in two units, 8/N.J.G.1
and IV/N.J.G.3 some of the aircraft carried No.6, and other
prisoners stated that aircraft of their units were equipped
with 4 or 5 or a mixture of both. In 5/N.J.G.3, for example,
Streuwelle 5 had superseded 4, whilst 8/N.J.G.1 was equipped
with a mixture of 4 and 6, the latter having been delivered in
October.
66. It is worth noting that aircraft equipped with
Streuwellen 5 or 6 are forbidden to fly over enemy territory
unless the boxes have previously been removed; no such
security measures, however, exist with Streuwelle 4.
67. One prisoner had heard that a JU.88 equipped with SN 2
and Flensburg had landed at an airfield in East Anglia last
summer and that the British were therefore in possession of an
SN 2. He naturally assumed that the latter apparatus was of
Streuwelle 4. Upon being asked how it was known that a German
night fighter had landed in England he replied that the
information had been given by British prisoners in Germany.
68. Not one of the present P/W could supply the respective
frequencies of Streuwellen 4, 5 and 6, but the radar servicing
mechanic P/W, who had been with N.J.G.4 up to the end of
October, was able to give a few details of 4 and 5; up the
time when he left the unit he had not encountered No.6.
69. He was certain that the frequency of 5 was slightly
higher than that of 4; No.5 has one more induction coil and
has a range exceeding No.4 by 5 kilometres, being provided
with an extra switch giving two range pictures, one at 5 km.
and one at 10 km.
70. He and other prisoners stated that no matter which
Streuwelle, 4, 5 or 6, is installed in an aircraft, the aerial
array remains unchanged and in all cases the same CRT's and
the same electrical length of connecting cables are employed.
71. The ground radar mechanic stated that outwardly there is
little difference between the three Streuwellen, and to avoid
confusion by the ground staff all boxes have the appropriate
number painted on the back; the boxes of different Streuwellen
are not interchangeable.
72. An example of the effects of jamming on the differing
Streuwellen was given by one of the present prisoners. In May
1944 all aircraft of his unit were equipped with Streuwelle 4
with provision for the alternative frequency. In July 1944,
however, Window jamming made the set useless.
73. In October 1944 Streuwelle 5 and then 6 were delivered,
both with the alternative frequency; these, however, were
seriously jammed by the so-called Rauschsender (electrical
jammer). It was found, however, that the remaining SN 2's of
Streuwelle 4 were not so seriously upset by electrical
jamming, and the result was that many crews asked for No.4
back again and their wish was granted.
74. According to the radar mechanic, the C.R.T's used in the
SN 2 are manufactured by both Lorenz and Siemens Nürnberg; the
latter are the more satisfactory in service.
75. One P/W had spent six months up to May 1944 installing
SN 2's in Me.110’s at Werl; he stated that installation work
for Ju.88’s was carried out at Gütersloh.
Serviceability of SN 2.
76. Considerable trouble in the servicing of the SN 2 was
experienced in misty or wet weather; the chief source of
trouble was rain water percolating into the pulse distributor
at the base of the antennae and was the cause of squints and
the blowing of valves.
77. In units recently examined, night flying tests are no
longer made; in the experience of one P/W of II/N.J.G.1 some
30% of the SN 2's were found to be u/s if the unit had been
stood down for more than three or four days.
78. Should radar equipment be found to be u/s after an
aircraft has taken off on an operation, the order is that the
sortie must be completed. This is a state of affairs which
rattles the crews, particularly if the SN 2 is not working and
they are robbed of backward cover.

SN 3.
79. As compared with prisoners captured up to the end of
November 1944, the present P/W gave the impression that
developments in the SN 3 have reached a further stage.
80. No prisoner has yet been encountered who has seen an
SN 3, but several had heard some scraps of information. It was
stated that the aerial array for this set is carried inside
the aircraft, and that Major SCHMAUFER, Kommodore of N.J.G.4,
is already flying an aircraft with this new search equipment.
81. There is no doubt that the Germans are in possession of
details of British centimetre A.I. and it has recently been
freely discussed by G.A.F. aircrew under the name "Grille"
(= grid).

TAIL WARNING.
SN 2 Tail Warning.
82. The present P/W were able to add considerably to
information obtained on night fighter tail warning equipment
and set out in A.D.I.(K) 700, paras.13-16. The present
interrogations, leave no doubt that the tail warners now
extensively fitted to German night fighter aircraft are a part
of the SN 2 equipment and that the picture appears on the SN 2
azimuth tube.
83. No height or bearing, but only a range reading can be
obtained from the backward aerial; forward and backward
displays do not appear simultaneously on the SN 2 tube, but
the set is provided with a switch which can select one or the
other. The method employed by the radar operator is therefore
to search for contacts with the forward aerials whilst
occasionally switching over to rearward aerial to see if an
enemy night fighter is following.
84. A tail warning tactic recommended to crews of III/N.J.G.1
is one of not taking immediate action when a rearward contact
is picked up, but of waiting until the range begins to close
in. When this occurs, the pilot increases speed and if the
blip closes in to 600 metres the pilot then takes evasive
action.
85. In the above-mentioned unit evasive action has been
ordered to take the form of a 180° hard turn to port or
starboard. If the pursuing aircraft has been seen by the crew,
the turn will be made according to its position; when the
pursuer is to port, the pilot of the night fighter will turn
in to port, or vice versa.
86. Previously, the tactics of the night fighter in those
circumstances was to peel off towards the pursuing aircraft,
but this resulted in losing 1500 to 2000 metres in height
which took about ten minutes to regain.
87. The newer tactic described above was ordered in
III/N.J.G.1 late in November to obviate this loss of height
and time and in that unit at least, the tactic of peeling off
is now forbidden except in extreme urgency.
88. A number of P/W knew the SN 2 tail warning as the D (or
Dora) Zusatzgerät (= the Dora attachment).
Fu.Bl.2 as Warning Device.
89. Yet another piece of German Airborne radio equipment, the
Fu.Bl.2 has been added to the list of sets that are capable of
giving a warning of approach of an aircraft.
90. Three P/W had heard that if the Fu.Bl.2 is switched on,
the red marker beacon warning lamp lights up when a radarequipped
aircraft is in the immediate vicinity.

Naxos as Tail Warning.
91. Crews of 8/N.J.G.2 had recently been told officially that
Naxos is capable of acting as a warning of the presence of
enemy A.I.–equipped aircraft. No such information had been
given to any of the other units examined during the present
interrogations, and none of the other prisoners knew that
Naxos had such capabilities.
92. It was pointed out by the one P/W concerned that Naxos
can do no more than give warning of A.I. radiation on a given
bearing, and range of the source of the radiation cannot be
measured; a bearing reading would, however, at least indicate
the probability of an enemy night fighter in pursuit.
HOMING EQUIPMENT.
The Naxos as an A.I. Instrument.
93. Since the first mention of Naxos by a prisoner in July
1944 (A.D.I.(K) 407/1944) and in the subsequent fuller account
of other aspects of Naxos and its tactical use (A.D.I.(K) 508
and 620/1944) it has frequently been reported how some night
fighter pilots have claimed to have used Naxos as an A.I.
instrument. There have been frequent claims usually by
lecturers at Werneuchen, that night fighter crews have shot
down four-engined bombers with their upward armament without
having used SN 2 at any time during the pursuit, but no
prisoner has been encountered with first-hand knowledge of
this fact.
94. Amongst the present P/W was a crew of 4/N.J.G.2 who had
six victories, each with the help of Naxos to a greater or
lesser extent. On five occasions they had located the bomber
stream with Naxos and had made the final approach with SN 2.
On the sixth occasion, however, they had shot down a fourengined
bomber with upward armament after an approach with the
sole use of Naxos.
95. In an attack on Berlin in March or April 1944, this crew
took off from Twente and flew towards the Baltic coast. At
about 54° 30' N; 11° 30' E some eight H2S contacts were
obtained from a height of 4,500 metres; one of these was
selected by manipulation of the Naxos brilliancy knob and
followed to about 13° E and then southward over Berlin.
96. The contact was held and followed from Berlin towards
Leipzig whilst the night fighter gradually approached its
target by making contact with the edge of the H2S cone,
throttling back to avoid penetrating too far and being
detected, then climbing and again making contact with the cone
in horizontal flight; a visual of the R.A.F. bomber was
obtained near Frankfurt-am-Main when the night fighter was at
a height of 7,800 metres.
97. The pilot closed in to make the attack but missed the
bomber; after a second unsuccessful attempt, the rear gunner
of the bomber fired a burst but missed. On the third attempt
by the night fighter the bomber was hit and was claimed as a
victory by this crew.
98. Early in October H2S contacts in the Naxos began to be
fewer, and such contacts as were made invariably disappeared
abruptly. The pilot who, incidentally, had a very high opinion
of his own capabilities, put this down to his radar operator
and blamed him for inefficiency; the result was that the crew
was continually quarrelling and was engaged in heated argument
when shot down.

The Naxos Aerial.
99. The radar mechanic had been with I/N.J.G.4 had attended a
Naxos course at Werneuchen in May 1944 and subsequently had
had some experience in servicing the apparatus. The
interrogation of this P/W on the subject of Naxos was carried
out with the co-operation A.I.2(g), with the result that he
was able to add some useful details to the substance of
A.I.2(g) Report No.1734.
100. In August 1944, Naxos began to be delivered to
1/N.J.G.4. The Naxos-equipped Ju.88’s first delivered to the
unit had the aerials installed on the after part of the
fuselage, but in later deliveries, the plexiglass dome
containing the aerials was fitted to the jettisonable hood of
the cabin – a position known as "Ausführung A". It was feared,
however, that the hood would be difficult to jettison and in
some aircraft the original position of the aerials was again
adopted.
101. When this P/W left I/N.J.G.4 in October 1944 the display
unit in use was the Naxos-Post, but he did not know which type
of aerial array was associated with this display, and he knew
of no further designation of any part of the equipment.
102. When Naxos was first introduced to the unit, the aerials
consisted of two plastic rods, of a material known as
Trollitul, of square cross-section with rounded ends and
measuring some 40 cm. in length and 5/6 cm in thickness. This
type of rod was, however later superseded by one of circular
cross-section with a diameter of 3-4 cm. and of the same
length.
103. These aerials were fixed parallel to one another and
about 3 - 4 cm, apart, being held in position at their central
points by a bakelite clamp made in two halves. Rotation of the
aerials was in a clockwise direction about an axis which was
vertical when the aircraft was in flying position, the aerials
cleared the aircraft skin by about 5 cm. Speed of rotation was
estimated by P/W at about 3000 r.p.m.
104. The aerials were mounted on a vertical axle running in a
ball Bearing flush with the aircraft skin and driven directly
from an electric motor which P/W recognised as being similar
to that illustrated in A.I.2(g)1734.
105. A copper lead came away from each plastic aerial rod and
joined the axle on which the aerial rotated; between the ball
bearing and the electric motor, a right-angle plug led the
signals received by aerial out of the axle and through a length
of single 1 mm. copper high tension wire to the Abgleichkasten
(cable matching box). P/W had also heard the term "Hochpass
Einrichtung" in connection with this box.
106. The cable matching box was shaped in cross-section like
a half ellipse and measured about 25 x 8 x 8 cm. The screws
securing the lids were sealed, and if any fault developed, the
box had to be sent away to the Gruppe repair and servicing
depot; the Staffel servicing staff were forbidden to break the
seals.
107. This P/W had seen a box open at the Gruppe at the
servicing depot and remembered that it contained a special
type of coil and detector of a type similar to that shown in
the A.I.2(g) Report. He was under the impression that there
were six such detectors.

Daily Inspection of Naxos.
108. The daily inspection of Naxos consisted of running up
the aerial array on ground batteries and using an ordinary
buzzer working from a torch battery as the transmitter. The
oblong box containing the buzzer had to be held so that one of
its ends, called the Strahlenseite (radiating end) pointed
towards the aerial and was in their plane of rotation. A
lightening of the appropriate part of the Naxos trace showed
that Naxos was in order.

AIRBORNE PLOTTING TABLE.
109. In the autumn of 1942 one at the present P/W had taken
part in some flying trials of a television device which was
being tried out at Werneuchen. For the purpose of the trials a
television receiver which was to repeat an 18 cm. square
picture of the Seeburg Tisch of a night fighter box, was
installed in a He.111.
110. In the trials reception was remarkably good and a clear
definition was obtained, the two spots of light representing
the friendly and enemy aircraft could be seen, but the only
means of distinguishing between the two was by the insertion
of a cardboard arrow on the Seeburg Tisch. In a similar way
cards bearing written vector instructions were placed on the
plotting table in view of the camera.
111. At that time the Germans were experiencing no
difficulties with box-control of night fighters and since
continual troubles were experienced with the television
transmitter the trials were discontinued toward the end of
1942.

GERMAN H2S - THE BERLIN GERÄT.
112. The same prisoner had heard of a German version of the
H2S called "Berlin" which he understood, was an improvement on
the British apparatus.

GERMAN KNOWLEDGE OF 100 GROUP R.A.F.
Activities.
113. In lectures on night fighting given to 8/N.J.G.1,
7/N.J.G.2 and 9/N.J.G.3 in October and November 1944, crews
had been given some details of the activities by 100 Group
R.A.F. which gave them the impression that the German Higher
Command has the greatest respect for the efficiency of those
responsible for planning that unit's activities. Some details
of these lecturers which prisoners from the above units could
remember show that the Germans are now accumulating
considerable knowledge of the equipment and tactics of 100
Group.
114. At recent briefings to 8/N.J.G.1 great importance had
been attached to the part played by 100 Group, and the many
occasions when warning of an impending attack had been given
and the aircraft had been airborne only to find the advertised
raid melt away, were now ascribed to the wizardry of that same
unit.
115. It was stated that the Group is equipped with Mosquitoes
and Lancasters - amongst whose crews were some expert bombers
- and that both these aircraft types carry the jamming
equipment which together with ground jammers upset the
commentaries and the SN 2. Long range intruders were also
ascribed to the same unit.
116. In a lecture on 100 Group given to 7/N.J.G.2 early in
November 1944, crews were told of so-called 'D' aircraft which
has the duty of putting out spoof R/T and W/T instructions to
German night fighters; one instance was related in which a
whole night fighter Gruppe had returned to base as a result of
spoof orders by one of these D aircraft. The W/T operators at
the 1ecture were advised that if they paid sharp attention to
their R/T and W/T signals they would be able to distinguish
between the false and genuine instructions.
117. It is now widely known by G.A.F. night fighter aircrew
that Mosquitos are equipped with a search equipment, the
Grille (= grid), that has a range of 15 kilometres (about 10
miles) and is said to work on a frequency of 3 cm. An
interesting extra piece of information given in these lectures
was that Grille was capable of homing on SN 2 transmissions, a
point that was noted by crews with some consternation.
A.D.I.(K) and S.D. Felkin
U.S. Air Interrogation. Wing Commander
27th January 1945"

[Bruce Dennis]

"SECRET A.D.I.(K) Report No.151/1944
THE FOLLOWING INFORMATION HAS BEEN OBTAINED FROM P/W
AS THE STATEMENTS HAVE NOT AS YET BEEN VERIFIED, NO
MENTION OF THEM SHOULD BE MADE IN INTELLIGENCE
SUMMARIES OF COMMANDS OR LOWER FORMATIONS, NOR SHOULD
THEY BE ACCEPTED UNTIL COMMENTED ON AIR MINISTRY
INTELLIGENCE SUMMARIES OR SPECIAL COMMUNICATIONS.

UNDERGROUND FACTORIES - NIEDERSACHSWERFEN AREA
(July 1944)
1. The following information on underground factories in the
Niedersachswerfen area was obtained from the Dutchman, who was
the subject of A.P/W.I.U. (2nd T.A.F.) 3/1945. Representatives
of A.I.2(a) and A.C.I.U. were present at the interrogation and
due thanks are rendered for their co-operation.
2. According to informant's story he began to work for the
Germans in January 1942, when he was employed as a labourer by
the 0.T. in connection with the electrical installations on
Lorient airfield. Thanks to diligent work, spare-time study,
judicious bribery and his self-assertive nature, he claims to
have risen rapidly in the world and to have acquired something
of a reputation both as an electrical engineer and as a reliable
satellite of the Germans.
3. After working as a foreman electrician on the Dutch coastal
defence works between Flushing and Den Helder, he was given the
task of supervising the installation of electrical equipment at
the Vught concentration camp. Finally, he asserts that at the
beginning of 1944 he obtained employment on the staff of S.S.
Gruppenführer und Generalleutnant der Waffen S.S. Dr. Ing
Kammler (see A.D.I.(K) 522/1944), who was entrusted with the
task of constructing important secret underground aircraft and
armament factories.
4. According to informant's account, Kammler placed him in
charge of the Abteilung Energieversorgung of Amt C.III of his
staff, which was charged with supervising the provision of
electric power to underground factories in course of
construction under the aegis of the S.S.
5. In this capacity, informant stated that in June 1944 he was
sent to Niedersachswerfen to arrange for the provision of
electric current to a number of underground sites which the S.S.
proposed to construct in the area, but at the end of six weeks
he was called away to undertake similar work at other projects
at Litomerice (Leitmeritz), Czechoslovakia, which will be dealt
with in a separate report.
6. It was apparently intended that he should return to Niedersachswerfen
on 1st December 1944 but before that date he had
decided, for motives best known to himself, to desert the S.S.,
and in due course he arrived inside the Allied lines.
7. As the well-known underground factory at Niedersachswerfen
itself was already working at the time of informant's visit, it
did not fall within his province and he only entered it on one
occasion. His information on this factory was therefore
disappointingly meagre, but he was able to make some general
remarks on the Niedersachswerfen complex as a whole which,
although based on impressions gathered during a short stay,
sound reasonably plausible.
8. As regards the function of the already native
Niedersachswerfen plant informant could not enlarge upon
existing knowledge. He was aware that Junkers were installed and
thought they were making "the turbine for the V.1 and V.2".
General.
9. According to informant, no less than seven underground
factories were projected by the S.S. in the Niedersachswerfen
area, and the project as a whole was known as Bauvorhaben X.
10. These sites comprised the already active factory at
Niedersachswerfen, the Woffleben site which was numbered B.3.
and on which construction work had already started by Ju1y 1944,
another site some 800 yards to the North West of the Woffleben
one to which the code name "Nie" had been allotted, and four
other projected sites numbered B.8, 3.9, B.11 and B.12 of which
informant pinpointed two.
11. It was pointed out that the letter 'B' stood for
Bauvorhaben and that in theory the number indicated the original
order of priority in which it was intended that construction
work should be undertaken.
12. Informant stated that all seven sites in the area were
destined to be occupied by Junkers and that all the plans were
drawn up by Ing. Spott, the chief construction engineer of the
parent Junkers works at Dessau. The factories, however, formed
independent units in that there were no underground connections
between the various sites.
13. The scheme was carried out under the supervision of S.S.
Sonderinspektion II, who were responsible for the provision of
labour and materials and, of course, security precautions, but
the actual construction work was in charge of the "Wifo"
organisation, a fact which may explain rumours which have
connected the Niedersachswerfen project with P.O.L. storage and
or production.
14. The S.S., however, provided technicians to assist in the
construction cork and they also installed their own agents, such
as informant, in order to exercise a general supervision and to
keep an eye on developments. There was said to be continual
friction between Junkers, who desired the best possible
standards of accommodation, and the S.S., who insisted that the
utmost economy must be exercised in every respect.
15. According to the planned schedule, the six new factories
were to be ready for occupation by February 1945 but in
informant's opinion they would not be able commence work before
July at the earliest, chiefly owing to the difficulty of
obtaining transformers.
16. In July 1944 the original Niedersachswerfen factory was of
course in operation, and construction work had started at
Woffleben, where informant thought that work had begun on two
tunnels, and possibly also at the site 800 yards to the North
West of Woffleben.
17. In August 1944 the underground sites at Litomerice were
given priority over the projects of the Niedersachswerfen area,
but informant did not know whether this was on account of the
urgency of the activity to be accommodated at Litomerice or
because of the greater rapidity with which these latter
projects, which largely occupied existing workings, could be
pushed forward.
Niedersachswerfen.
18. As P/W had only been inside the Niedersachswerfen complex
on one occasion he could only give a very general and not
particularly reliable impression of its internal layout. He
confirmed a previous informant's statement that the workings
consisted of two main tunnels serving a number of workshops, but
thought that the workings, though quite level, were not
straight, and that the standard gauge railway line did not run
into the tunnels.
19. He had noted that the entrances were strengthened with
concrete reinforced by railway metals, and that inside the
galleries weak places were also reinforced with concrete for
distances of up to 100 metres in some cases. He could make no
statement on overburden.
20. Informant believed that in the floor of the galleries there
were a drainage channel one metre wide and another channel 75
cm. wide for the piping of the air conditioning system. Some of
the power cables were installed in third channel in the floor
and others, together with the wires for the lighting and the
telephone cables, were carried on iron supports along the walls
of the galleries.
21. Informant believed that a power supply of 600 kW was
required to run the air conditioning plant and that the capacity
of the Niedersachswerfen stand-by plant was insufficient for
this. He therefore believed that, if normal supplies could be
cut off, the air conditioning system would necessarily cease to
function and that the galleries would start to drip, with
disastrous results to the virtually irreplaceable machine tools.
Woffleben. (B.3).
22. In July 1944 the Woffleben site enjoyed the highest
priority of the six new projects envisaged in the Niedersachswerfen
area. At this date two entrances giving access to two
parallel main tunnels running roughly N.W. - S.E. through the
hill were said to have been started, and several subsidiary
galleries running off the main tunnels had also been commenced.
It was believed that considerable difficulty was being met with
on this project owing to underground springs and streams
encountered in the course of the excavations.
23. It was believed that when construction work was completed
the site would be taken over by Junkers for the manufacture of
aero-engines.

Woffleben West ("Nie").
24 The project 800 yards North West of the Woffleben workings
and designated by the code name "Nie" was the last of the
Niedersachswerfen sites on the official priority list but,
strangely enough in July 1944 it was the only site besides
Woffleben on which construction activity appeared likely to
begin in the immediate future.
25. One entrance only was planned, and this was to be located
at the south-western corner of the hill. This entrance was to
give access to the main tunnels running the length of the hill,
and these tunnels were to be connected by a network of some 40
or 50 cross-galleries. A servicing gallery was to run round the
whole site in order to facilitate transport; the workshops were
to be arranged to give a production flow running northwards from
the entrance, the finished articles being collected at the
northern end of the site and brought round to the entrance by
the servicing gallery.
26. This factory also was earmarked for Junkers, but informant
had no reliable information as to the purpose for which it would
be utilised. In July 1944 instructions were given to extend the
existing power cables as far as this site, so that construction
work could be commenced.

Ilfeld.
27. Besides the above-mentioned sites, another underground
Junkers factory was planned in the hills a short distance to the
West of the village of Ilfeld some two miles North of
Niedersachswerfen. The entrance was to be in the vicinity of
110360 GSGS 4416 Sheet Q5, and this was to serve a complex of
galleries arranged on the conventional grid pattern. In July
1944 construction work had not begun but a small group of
contractors' huts had been put up near the proposed entrance.

Appenrode.
28. Although informant knew that a total of seven underground
factories was envisaged, the only other projected site which he
was able to identify was in a hill between the villages of
Appenrode and Ilfeld and to the North of the road connecting the
two. It was understood that the entrance would be located in the
neighbourhood of 087361.
29. In July 1944 two contractors' huts had been put up on the
site but at that date construction work had not been started and
power cables had not been brought up to the area.

Power Supplies.
30. Informant alleged that in July 1944 all power supplies both
for the already active Niedersachswerfen factory and for
construction work at the other sites was supplied exclusively by
the 110 kV line from the Bleicherode power station. At the new
sites the 110 kV line was to be led directly into the tunnels
and the transformers intended to serve the factory machinery
were to be installed inside the workings, and informant
understood that this system was already obtained at the

Niedersachswerfen factory.
31. It was intended that when other sites came into operation,
power would also be supplied by a new 110 kV line running from a
power station at Frose in the Magdeburg area to Woffleben, where
it would join the grid serving the underground factories in the
Niedersachswerfen district. As in the case of the existing line
from Bleicherode, the power was to be stepped down in the
Niedersachswerfen complexes to 20 kV and 6 kV in the first
instance.
32. According to informant's story, the power stations at
Bleicherode and Frose would therefore be the sole sources of
electricity supplies for the underground plants around
Niedersachswerfen. He explained that it was not intended to draw
on other sources partly on account of the load already carried
by other power stations and partly because of the acute shortage
of materials needed for the construction of transmission lines
which made it necessary to rely on generating stations located
reasonably near the factories.
33. The new line from Frose was said to be intended to run
South-West across country from Frose for about one third of its
length and thence almost due West to Woffleben. The most direct
route was chosen in order to effect the greatest possible
economies in cables and pylon.
34. In July 1944 the holes for the pylons had been excavated
and sufficient pylons were on hand at the Frose and for
completing about one quarter of the proposed line. In the
following month, however, some of those pylons were
requisitioned for the Litomerice projects, which in the meantime
had been given a higher priority, and some of the new pylons on
order were also later diverted to Litomerice.
35. The contract for supplying the pylons was held by the firm
of Seidl of Falkenstein (Vogland) who were said to be able to
deliver three daily.

Emergency Power Supplies.
36. Unfortunately informant did not claim to be conversant with
the emergency power supply system in the Niedersachswerfen
complex. He stated, however, that he understood that it
conformed to the general instructions on the subject issued by
Generalleutnant Kammler on 1st August 1944, and he had the
foresight to bring with him a photostat copy of the document in
question.
37. In his instructions Kammler draws the attention of his
Sonderinspektionen and S.S. Führungsstäbe to the fact that the
emergency power plants proposed by these bodies are of
excessively high capacity. He adds that as a measure of fuel
economy emergency plants are only to serve such appliances as
necessary for the safety of the personnel, i.e. lighting, water
supplies end air conditioning.
38. The two last-named systems are to be confined to the
absolutely necessary minimum and Kammler formally forbids the
connection of any normal equipment to emergency generators.
39. Future demands for emergency sets are to show the capacity
of the act divided into the requirements for lightening, water
supplies and air conditioning. The projected requirements for
lightning are to be cut down to the necessary minimum since, if
the normal supplies of power fail, normal activity will cease
ipso facto. For the same reason, good grounds are to be shown
for the maintenance of air conditioning and water supplies
during the period when normal power is cut off.

Railway Services.
40. The plans for the Niedersachswerfen complex of underground
factories provided for a now ring railway connecting E11rich,
Ilfeld and Nordhausen and serving the whole of the sites. For
the convenience of workers proceeding between their quarters and
their place of work as well as between the various factories, a
train was to be run every three minutes on this line.
41. In addition, a large marshalling yard was envisaged on both
sides of the village of Woffleben and on both sides of the
existing Nordhausen - Ellrich line.

Personnel.
42. Appendix I contains a list of some of the principal personalities
connected with the Niedersachswerfen complex of sites.
Construction work at Woffleben was being carried out by inmates
of the Buchenwald concentration camp under the supervision of
"Wifo" personnel.
43. When all the factories were in operation it was expected
that they would employ a total staff of some 45,000 workers. In
July 1944 some personnel was already billeted in Ellrich and
Nordhausen and it was rumoured that when the various sites came
into production these towns and the area surrounding them would
be evacuated to provide accommodation, especially for married
employees and their families.
A.D.I(K) and S.D. Felkin
U.S. Air Interrogation. Wing Commander
5th February, 1945.

APPENDIX. SECRET.
PERSONALITIES CONNECTED WITH UNDERGROUND ACTIVITY IN THE
NIEDERSACHSWERFEN AREA
S.S. Gruppenführer und Generalleutnant der Waffen S.S. Dr. Ing.
H. Kammler.
Entrusted by Himmler, in his capacity as the head of the
S.S. Wirtschaftsverwaltungs Hauptamt, with the execution of
the Deutsches Geheimbauprogramm, which comprised important
secret underground factories.
Head of the so-called Stab Kammler which was created for
this purpose (see A.D.I.(K) 522/1944).
S.S. Hauptsturmführer Dipl. Ing. Geissen.
Head of S.S. Sonderinspektion II, which was charged with
the supervision of construction work on the sites in the
Niedersachswerfen area.
S.S. Sturmbannführer Fleto.
Head of Amt C.III (Technische Fachgebiete) of the Stab
Kammler and in this capacity in charge of the technical
side of construction work.
Sturmbannführer Skowronneck.
Head of the Abteilung Maschinen of Amt C.III of the Stab
Kammler. A subordinate of Flote and responsible for the
provision of the necessary machinery.
Major Regierungsbaurat Dr. Dr. Ing. Trautvetter.
In charge of the section of the S.S. Wirtschaftsverwaltungs
Hauptamt responsible for the provision of materials.
Dr. Neu.
"Wifo" representative in charge of construction work in the
Niedersachswerfen district.
Ing. Schwatz.
Chief "Wifo" engineer at Niedersachswerfen.
Ing. Reinzhagen.
"Wifo" engineer in charge of the electric,
gas, heating and air conditioning equipment.
at Niedersachswerfen.
Ing. Spott.
Chief Junkers constructional engineer. Responsible for the
plans for all the Niedersachswerfen sites.
Dipl. Ing. Pönitsch.
Junkers constructional engineer responsible for
electricity, gas and similar supplies."

[Bruce Dennis]

"SECRET A.D.I.(K) Report No.157/1945
THE FOLLOWING INFORMATION HAS BEEN OBTAINED FROM P/W
AS THE STATEMENTS HAVE NOT AS YET BEEN VERIFIED, NO
MENTION OF THEM SHOULD BE MADE IN INTELLIGENCE
SUMMARIES OF COMMANDS OR LOWER FORMATIONS, NOR SHOULD
THEY BE ACCEPTED UNTIL COMMENTED ON AIR MINISTRY
INTELLIGENCE SUMMARIES OR SPECIAL COMMUNICATIONS.


LUFTWAFFE MORALE.
(August to December 1944)
1. This report is an endeavour to assess and analyse
Luftwaffe aircrew morale in the period of five months from
17th August 1944, on which date a similar assessment was made
in A.D.I.(K) 473/1944. The number of aircrew prisoners
interrogated for the present review, amounting to 246,
comprises the largest sample since 1940.
2. The majority of these prisoners have been tough and well
drilled in security; at no point did the proportion with high
morale fall lower than 51% and, as may be expected, the period
when it reached this lowest ebb was during the German
withdrawal in August. Since then, the proportion of high
morale amongst all aircrew has risen steadily until, in
December, it was found to stand at 64%, with day fighters even
higher at 74%.
3. It should be noted that the present report deals
throughout solely with aircrew morale and that ground
personnel are not taken into account. The morale of the ground
personnel, judging from recent samples, is just the same as it
has been for a long time – bad.


THE BASIS OF MORALE.
4. The basis of G.A.F. morale remains very much the same as
before, and can be said to consist of a mixture of the
following factors: the natural discipline of nearly all
Germans, youth, love of flying, patriotism and a general
ignorance of the real facts of the war. It is true that
aircrew have very few amusements and almost no time off, but
they continue to live fairly well; in fact, better than any
other section of the population. They experience no hardship
comparable to that of the front-line soldier, and they receive
on the whole less bombing than either the army or the
civilians.
5. Expectations and promises for the future play a large part
in maintaining morale and still continue to be believed. As
one fighter-pilot said: "In the autumn we were guaranteed
2,000 new fighters. They have turned up, and this makes me
prepared to believe that the other new weapons and aircraft
promised will also turn up". However small the "come back" of
the Luftwaffe might seem to the Allies, it has helped the
ordinary German pilot to believe that the inventors and
technicians still have the situation in hand. The promise of
large numbers of jet aircraft for the spring has had the same
effect.
6. Many, though a decreasing number, of the younger P/W still
profess belief in ultimate German victory, a belief which is
quite unconnected with any logical process of thought
whatever, but depends on what can only be termed as mystic
belief in German invincibility. This faith is no doubt
fostered by the good fight they are putting up in spite of the
enormous difficulties caused by bombing and the shortage of so
many necessities inside Germany.
7. It cannot be said there is much desperation in their
courage. Rather is it a quiet resignation to the fact that
they have no alternative to fighting on. Certainly the impetus
derived from fighting on German soil against unconditional
surrender helps to counteract strain and war weariness; but
although attempts have been wade by German propaganda to
instil a kind of "Battle of Britain" spirit, it is doubtful
whether it has succeeded.
8. One of the smaller props to morale has gradually been
upset. When the Luftwaffe was in its prime, outstanding aces
were carefully built up as heroic types, an example to others.
This hero-worship, to which the Germans are so addicted, was
encouraged to what we would consider an inordinate degree. But
by now most of the aces have been killed and others, like G
GALLAND and PELZ, no longer fly on operations and are even
accused of becoming out of touch with the operational
personnel. At the same time the camaraderie between officers
and men has become less.
9. The new appeal is based more on staple patriotism and fear
of the consequences of defeat. A frequent propaganda theme is:
"Life will not be worth living after the war". The horrific
picture of a conquered Germany, easily concocted by GOEBBELS
from unofficial Allied pronouncements, is well calculated to
make men fight to the bitter end.
10. Much greater than fear of defeat at the hands of Britain
and America is dread of Russia. "Sieg oder Sibirien" - Victory
or slavery in Siberia, is a slogan which has a considerable
effect, an effect not unconnected with a sense of guilt for
what Germany has done above all to the populations in the
East. Manly realise that such wrongs avenge themselves, but
nevertheless justify their conduct by persuading themselves
that they are upholding a higher civilisation.
11. Among aircrew less resentment of our bombing policy is
felt than might be expected. The destruction of so much of
both private and public property and fine cities, however, not
to mention the casualties involved, helps to foster a certain
feeling of futility about the future, and even a wish to
escape it. Thus in some ways continued resistance is a
putting-off of an evil day - with the small, but to them
worthwhile chance that the Allies might quarrel, the German
technicians produce a trump, and defeat might be avoided in a
triumph of defensive warfare.


A STATISTICAL ANALYSIS OF MORALE.
12. The three tables presented below show morale at time of
capture; the assessments are those made by the original
interrogators on the Continent, and differ slightly - almost
always for the better - from the assessments given at the end
of A.D.I.(K) reports in which allowance is not always made for
the weaknesses which develop under prolonged interrogation and
in the isolation of theme from the sustaining effect of his
group.
(a) Period August – November 1944.
August Morale.
Type of Unit. No. of P/W High. Fair. Low.
Bomber 22 12=55% 6=27% 4=18%
Day Fighter 14 6=42% 6=42% 2=16%
Others 7 4 -
Total 43 22=51% 15=35% 6=14%
Average age - 23.3 years.
September - November Morale.
Type of Unit. No. of P/W High. Fair. Low.
Bomber and
transport 18
+
11=61% 2=11% 5=28%
Day Fighter 10 7=70% 2=20% 1=10%
Night Fighter
and N.S.G. 15 8=54% 2=13% 5=33%
Others 2 2 - -
Total 45 28=62% 6=13.5% 11=24.5%
Average age - 23.3 years.
+ This figure includes the only bomber crew captured
between 16th August and 18th December; this crew comprised
the three survivors of a V-1 launching He.111 which
ditched in the North Sea on 6th October.
Notes on the above Tables.
(1) Even in the catastrophic days of August, 51% of the
Luftwaffe aircrew captured showed good morale, and of the
rest 35% could be said to have fair morale.
2) Although the sample is too small to be satisfactory,
it is perhaps significant that the morale of the crews of
heavy aircraft retrained steadier than that of the fighter
pilots which, however, recovered more quickly.
(3) The absence of any marked defeatism in the Luftwaffe
directly after the attempted Putsch of 20th July and the
catastrophe in France indicates the extent to which its
personnel are imbued not only with a sound fighting spirit
but with esprit de corps. Though of an age which has only
known a Nazi upbringing, flying personnel of the G.A.F. are
not very politically minded. Loyalty to the regime which has
done them personally no apparent harm, and which has often
benefited them, is strong, as there is no substantial
alternative.
(4) The fact that there was a virtual debacle in the air
at the same time certainly had a depressing effect, but
there was always the excuse of overwhelming superiority on
the Allied side. Furthermore, promises were made that a
great new fighter force would be formed and a new training,
programme was put in motion. It was believed by many that
the new jet-propelled aircraft would enable the Luftwaffe to
make a startling come-back with qualitative superiority. In
fact the 0.K.L. reacted to the new situation with vigour
which gave a new hope to a depressed but eager-body of young
airmen; whose mental horizon is as limited by flying as it
is by propaganda and education.
(b) Period December 1st 1944 - January 1st 1945.
14. By the end of November 1944 it seems that the German Air
Staff considered that the Luftwaffe had been sufficiently
nursed back to health to be employed on a large scale in
tactical support of the Army. At the same time, in the absence
of an adequate bombing force, night-fighters were sent in
considerable numbers in an attempt to cause dislocation over
the Allied lines at night. The result has been the largest
batch of aircrew prisoners, since the Battle of Britain.
15. The morale of the 158 P/W, assessed as before at time of
capture, is analysed as follows:-
State of morale
Type of unit N° of
P/W
High Fair Low Average
Age
Day Fighter 80 59=74,5% 14=17% 7=9% 22.9yrs
Night Fighter 54 28=52% 19=35% 7=13%
Others, incl.
Bombers,transport
and recce crews
24 14=58% 8=33.5% 2=8.5% 23.2yrs
Total 158 101=64.6% 41=26.5% 16=10% 23.0yrs
Notes on the above Table
(1) The over-all improvement in morale seems very slight
against the previous three months. This steadiness is in
contrast to the fluctuation noticed in 1943 during the same
period, i.e. between the low point reached with the
landings in Italy and the defection of BADOGLIO, and the
recovery connected with the bogging-down in Italy and the
beginning of reprisal raids on England. Unfortunately the
method of assessment was not identical with the present one
and the samples much smaller but it is interesting to note
that in the period September to mid-November 1943 the
percentages of high, fair and low morale were found to be
61% 31% and 5%, while in the period mid-November to January
1944 they were 83%, 17% and nil.
(2) The only marked improvement is among day fighter
pilots, whose morale has jumped from 42% high in August to
74% high in December. This has been due (a) to careful
husbanding of strength for a big effort. (b) the
maintenance of the fighter aircraft industry in spite of
Allied bombing and (c) the successful defence of the
frontiers of the Reich.
(3) While these three factors also apply to the whole of
the Reich defence force, the morale of one branch, the
night-fighters, has noticeably declined although they are
better trained and more strictly selected, and not long ago
were the most steadily successful part of the Luftwaffe,
they show an inferior spirit to the day-fighters. One
reason for this is that they have an increasing sense of
frustration, caused by jarring of signals channels and
interception equipment and frequent failure owing to
"spoofery" to contact bombers at all. They also show a high
level of intelligence, which does not help morale. They may
fly blind, but they think less blindly about the war.
(4) The majority of these P/W were captured during the
RUNDSTEDT offensive and before they were plainly aware of
its failure. That it could be launched at all gave, a
certain fillip to morale.
(5) The fighter unit showing the most consistently good
morale is J.G.4, with J.G.2 coming second.
(6) It would be wrong to consider all those with morale
assessed as fair to be only fair fighting material. In a
unit with a high spirit - which applies to most - they
would be carried along with the majority, and would hardly
be aware themselves of the chinks in their armour.
(7) Fewer P/W are found to have listened to Allied
broadcast propaganda than at any time during the last 18
months. This is partly due to the fact that most are
fighter pilots, as opposed to bomber crews as in the past,
and live in less permanent quarters, and partly because
morale itself is higher.


THE EVENTUAL UNDERMINING OF MORALE.
16. Interrogators on the Continent who see P/W in the first
days after their capture have found them extremely tough
almost without exception. In so far as the time taken to break
down a man's security is an indication of his fighting spirit
and not of improved security instruction, morale is higher
than it has been for some time. It is, however, not so deeply
ingrained. P/W to-day are not only slightly younger than in
the past, but each time they come from a later age-group. This
means they are more unformed. Fewer are intelligent and more
are bone-headed, and the eventual undermining of security, and
later of morale, is made easier by this fact. With them
security is often merely an induced state with automatic
reactions rather than intelligent attempt to continue fighting
although a prisoner or war. Once it breaks they tend to talk
freely. This applies chiefly to N.C.O.'s and other ranks.
17. With most younger officers the basis of the high morale is
somewhat different. They attempt to explain their professed
faith in victory, which for them amounts to avoiding defeat,
on the score of superior fighting ability, V-weapons etc. But
they also tend to be less fact-proof and easier to reach with
argument, though only with much time and trouble. Older or
senior officers, who know more facts, are nearly always
prepared to admit that Germany has lost the war, but their
discipline and sense of responsibility clearly keeps them from
showing any defeatist spirit to the men under their command.
18. It is nevertheless startling to find how different is the
attitude of most P/W after a week or so of being moved from
place to place and being interrogated. During this time they
learn with their own eyes or from the people they meet a great
many unlightening facts and some truths; they have time to
reflect on the tremendous material superiority of the Allies
which they see behind our lines; if they happen to pass
through London, this especially brings home to them the
swindle of their own propaganda.
19. The young generation in Germany has so long been denied
the possibility of finding out the other man’s point of view
that when he gets the chance of doing so he frequently
discovers he cannot answer it. This is a weakness of which
interrogators have learnt to take advantage. If a patient and
serious attempt is made to open a P/W's eyes to the facts he
has been denied, for him the GOEBBELS machine begins to
operate in reverse.
20. This very susceptibility of Germans to propaganda might
suggest that their re-education after the war may not be so
difficult, but it should be remembered that the interrogators
achieve little more than a rather static "deconditioning and
with the assistance of depressing circumstances. Any eventual
"reconditioning" must depend on a new dynamic of ideals, and
social and political loyalties, which are at present all too
painfully absent.


CONCLUSION.
21. It would seem that since morale is not built on reason,
but on blind faith, loyalty and patriotism, it will only break
down when facts or a conflict of ideas, successfully undermine
the original basis. In so far as these destructive influences
operate at all in the field, the whole of German propaganda is
working, not unsuccessfully, to exclude them. As a result
aircrew on capture continue to show good fighting spirit.
22. Morale did not slump seriously during the disastrous days
of the summer, and does not become unduly depressed by failure
or heavy losses, or even as a result of land reverses. This
suggests the conclusion that taking flying personnel in the
Luftwaffe as a whole, morale will not break as long as they
have aircraft and petrol, the army continues to resist, and
they themselves are told to go on fighting.
A.D.I.(K)&
U.S. Air Interrogation. S.D. Felkin,
8th February 1945 Wing Commander"

[Dan O'Connell]

Fascinating, especially by U.S. Air Interrogation.

[ju55dk]

ADI K 065 5/NJG 101 Ju 88.
Junker

[Bruce Dennis]

"(49) A.L. No. 19 (Sheet 2) 29/9/45
Interrogation of Baron Von Schalcky CIOS File 24-15

JAGDSCHLOSS
The original plan for Jagdschloss provided three models
covering the following frequency ranges; 75 to 120 Mcs; 120 to
160 Mcs. Jagdschloss A was actually operated between 130 and 160
Mcs, with a frequency change requiring only five seconds. This
frequency change was among a choice of four pre-set frequencies
in which the proper dial settings for transmitter, receiver, and
TR-antenna coupling systems were indicated with special markers.
The antenna was designed to work over a two to one frequency
range with the limit set by tactical requirements rather than by
standing wave ratio.
Jagdschloss was first used in April 1944 and by February
1945 it was felt that the Jagdschloss coverage of Germany was
complete and with considerable overlap. The normal usage of
Jagdschloss was described as "Luftlage"; that is, it was used
for early warning and to maintain a watch of all aerial
activities. It was used in this capacity to assign targets to
either ack-ack control or GGI installations and, as noted below,
was used directly for fire control under some conditions.
The maximum range ever obtained on a Jagdschloss was said
to be 250 kilometers on an 8th Air Force formation. Ranges of
180 to 120 kilometers could be obtained normally. However, these
ranges were obtained with the A scope which was normally used
for tuning and testing purposes. In normal operation for
Luftlage, the range of Jagdschloss was limited by the 120
kilometer sweep length on the Sternschreiber (P.P.I.)
In the Berlin area on several occasions during August and
September 1944, Jagdschloss data was used directly for fire
control. This was done by assuming the altitude shown by our
bomber formations to be a constant which was found statistically
to be quite an acceptable assumption. Then the range and azimuth
of the formation was obtained by Jagdschloss and appropriate
data was transmitted to the flak batteries. The battery then
fired a controlled barrage, setting the fuzes in such a way as
to cover about 2,000 foot altitude spread. The Baron said this
procedure was considered very effective against our 8th Air
Force bomber formations. Incidentally, the Baron was well
acquainted with our division of bomber activities and was
familiar with 8th Air Force organisation and procedure.
Jagdschloss was fitted with a remote transmission system
which transmitted the Sternschreiber picture up to 150
kilometers OVER WIRE TRANSMISSION LINES. No specific mention of
direct use of this facility was made.
Several Jagdschloss radars were in various stages of
development: One of these sets was the 50 cm set on which the PW
had been running tests. This was another Jagdschloss by Siemens
Company. In addition a 25 cm set of similar characteristics had
been developed by Telefunken and was known as Forsthaus F. This
set used a conventional type tube in the transmitter known as
Scheibenröhren. The details of its construction were not known
to von Schalcky. A 9 cm. Jagdschloss set, known from other
sources as Forsthaus Z, was also in development by Telefunken.
The PW indicated that Forsthaus was the Telefunken name for
"Luftlage" radar whereas Jagdschloss was the name used by
Siemens. The effort on these radar developments was to obtain
higher discrimination so as to provide less susceptibility to
Düppel. Von Schalcky was of the opinion, however, that going to
narrower beams, although it provided a smaller pulse packet and
thus higher discrimination, caused sufficient loss of target
return due to the shorter length of time that a target was
illuminated as the radar antenna rotated, to set a limit to this
technique. His reasoning is probably correct if one considers
the low peak powers used in precision German radar. The PW also
had the opinion that the higher frequency sets (above 1000 Mcs)
were less satisfactory for early warning due to what he called
"Troposphere" reflections.
Several anti-"Düppel" (anti window) measures had been
developed and were being tested on the 50 cm. Jagdschloss. It
was interesting to note that the procedure was to utilize 8th
Air Force Window for test purposes rather than bothering to drop
their own.
1. Phosphor clearing device.
This was a simple expedient which was made necessary by a
characteristic of the Sternschreiber phosphor. Apparently the
decay time was so long that Window echoes would tend to build up
large, fully, illuminated areas giving a sort of compound
jamming effect over a period of time. The expedient was to turn
off the beam for one or two rotations of the antenna system and
to radiate the screen from an infra-red source during this off
period. The existing echoes were thus erased. Equipment for
doing this automatically was just being completed.
2. Film frame comparison method.
Exposure of two successive frames of the Sternschreiber
presentation were made on the same piece of colour film. The
exposure for frame A was made with a red filter and exposure
frame B was made with a green filter. Each rotation required six
seconds, thus the total exposure required 12 seconds. The
equipment for doing this job had been developed and built by
Zeiss. The existing development model had been destroyed by von
Schalcky at Heidhof. The equipment was arranged so that one
minute after the exposure, the colour film could be projected on
a screen. Due to the additive effects of green and red, fixed
echoes appeared as black marks or "streams". However a moving
target in which the succeeding exposures were displaced in
accordance with the motion appeared as a "beetle" having a green
head, black center, and red tail. The green, of course, points
in the direction of motion.
Von Schalcky distinguished between heavy 8th Air Force
daylight window and thinner RAF Window. Heavy Window gave
definite black areas or "streams". However, Window occurring in
small separated clumps sometimes gave the effect of motion due
to the random shifting of dipole orientation with consequent
random displacement of the effective center of the Window cloud.
This effect was considered a disadvantage of this
particular A/J system, the principal aim being to enable
distinction of fixed and moving targets.
3. A frame storage moving target indicator method was being
developed and had undergone preliminary tests. An iconoscope
mosaic storage was employed. The Baron did not think that this
method used coherent pulse. The same disadvantage of the
difficulty of distinguishing between aircraft and small clumps
of Window was encountered as in the case of the photographic
method.
4. Siemens was developing an adaption of the Laus or coherent
Doppler to Jagdschloss, the intention being to alter the display
of moving targets on the Sternschreiber, allowing fixed echoes
to be presented normally. A third detector circuit derived a
pulse signal from the beating Laus of a moving target. This
pulse was applied to the radio deflecting system in such a way
that moving targets tended to trail in towards the center of the
tube as shown in the sketch below.
The Sternschreiber tube had a double phosphor similar to
our P-7, in fact, adapted from the P-7. The flash trace is blue
but in the Sternschreiber the afterglow is green and apparently
of longer duration than our yellow. Von Schalcky did not know
the chemical details of this phosphor. He thought a persistence
of ten minutes was obtained.
Comment was made that our daytime 8th Air Force jamming was
picked up often on the 50 cm. experimental Jagdschloss and that
it was never possible to see aircraft in the jammed sector on
the Sternschreiber.

B. Freya.
The Dreh Freya was considered very inferior to Jagdschloss for
general search and coverage because of the serious nulls in the
vertical antenna pattern.
The modification of the Freya Laus, known as "Windlaus",
was designed to enable cancellation of any particular Doppler
beat caused by wind drift of the Window. Two oscillators were
used, one to lock the transmitter frequency and a second for
comparison in the receiver. The frequency of the receiver
oscillator could be adjusted independently so that a particular
Doppler frequency produced no output, thus wind-blown Window
echoes would not appear as a Laus presentation, whereas fast
moving aircraft would still be detected as moving targets. This
was said to be in use on a considerable number at Freya
installations.
The use of centimeter listening receivers, either, on Freya
mounts (as at Kothen airfield) or in separate installations, was
quite common as an early warning system for detecting the
approach of H2S or H3X.

C. Fire Control Radar.
The PW stated that the Würzburg Frequency spread was 63 to
50 cms (476 to 600 Mcs). He stated this twice, and was rather
positive on the point.
Gustav is a code name for Würzburg Riese G and consists of
Freya radar added to the normal Riese. Freya equipment is
located in the far end of the can necessitating very slight
alteration in the normal layout. Two antenna arrangements are in
use, in one a single vertically polarized radiator one wave
length long being mounted in front of the normal Würzburg
antenna and using the normal Würzburg reflector to obtain a
measure of directivity. The second arrangement utilizes two
dipoles one on each side of the normal antenna, again vertically
polarized. Von Schalcky did not believe that reflector elements
were used with this antenna arrangements and that the Würzburg
dish was the only other element involved. In addition to Riese
G, there was a variation with a broadband Freya installation
known as the Riese G-la. The use of these combinations as
understood by this PW was simply to aid in putting the Würzburg
on target. He did not believe they were used for range, only
A/J.
The Mannheim was preferred over either Würzburg for
tracking in normal conditions but it was considered less
effective in the presence of jamming than the Würzburg. This was
attributed to the ability of a good operator to interpret a
jammed scope on the Würzburg, a procedure impossible in the
Mannheim meter presentation. It appeared the Mannheim scopes
were not usable where jammed. The use of aided tracking on the
Würzburg D, on the Riese, and on the Mannheim, was common as a
measure against jamming which was not effective all the time. A
fixed tracking rate could be set in by the operator.
Von Schalcky did not know of any centimeter fire control
sets.

D. Fire Control Procedure
With regard to predictors used for fire control
computation, von Schalcky knew only of the KG-40. He understood
that the preferred SOP was to use optical direction and radar
range in all possible circumstances including night operations.
In this connection, the small Würzburgs were used for
searchlight control, the optical system built in the KG-40 being
then applied for final direction finding. Using the Riese, he
thought it was nearly always possible to obtain slant range in
the presence of our jamming. He felt that the KG-46 was still
the most widely used predictor in the GAF defense system.
Use of Wurzburg Riese and Riese G's for fire control was
said to be quite common and extensive.
A procedure for utilising data from several different
radars as in the Gross-battery was mentioned. In this, a
specially trained operator surveyed Selsyn relayed data from the
several radars associated with the battery and mentally selected
and averaged the best appearing data. That is, if two radars
were producing roughly the same information but a third was
giving different indication, he would utilise the data from the
two more consistent sets, delivering this information by phone
to the KG-40. With this installation, which was said to be
fairly common, it was thus possible to change instantly from one
radar to another for control purposes.
In a defense area such as a city or other specific target,
all defenses were controlled from a central Kommand post. A
Jagdschloss was associated with this Kommand and was used in
assigning targets to ack-ack or fighter defenses. In addition,
Wassermann or other height finding radar would usually be
associated with the Jagdschloss. In the case of fire control, if
the battery was unable to track an assigned target because of
jamming, it was usually instructed to fire a barrage on the
basis of Jagdschloss data. In a few cases, arrangements were
made for relaying information between adjacent batteries by
phone but the P.W. did not believe this to be as common as the
practice of using Jagdschloss data. Provisions for automatic
transmission of data between batteries had been worked out but
were not in common use.

E. GGI Procedure.
Naxos had been in use since April 1944 for homing on
British H2S radar.
The practice of triggering our IFF from both ground and air
installations was common and, it was felt, quite successful.
Also few night fighters had recently been fitted out for
triggering what must have been Oboe Mark II in the RAF planes.
Automatic Seeburg was not liked as well as the manual
because of the roughness of the data plotted when a radar would
"spring" or deviate from the true tracking course. A manual
table allowed smoothing in the process of manual plotting.

F. Allied RCM.
As-noted previously our jamming was not considered
effective in jamming range on the Riese. However, against
Würzburg D and Mannheim, the combination of Düppel and
Störsender was quite effective, especially after October 1944.
Screening of Freya was more effective in night than in the day
time but was never considered a serious effort. This PW had the
understanding that screening was also directed against
Jagdschloss and knew of cases where Allied planes had circled a
Jagdschloss site continuously during operations in that
vicinity. The overlapping coverage of Jagdschloss made it
possible nearly always to obtain the necessary information,
though a particular set was out. The maximum range of
Jagdschloss as used operationally was 120 kilometers.

G. Centimeter antennas.
The PW knew of the poly-rod antennas used in Naxos and the
use of a parabolic reflector copies from H2S. The parabolic
reflector antennas were chiefly by Siemens.
One other type of centimeter antenna of interest was a
slotted wave guide as shown in the sketch.
The slot is tapered to provide uniform radiation from all
sections of its length. This was Telefunken development, known
as Holstraehlen.

(47) A.L.No.14 (sheet 20) 24.9.45
Magnetrons & Klystrons
Interrogation of Drs. Kleen, & Lerbs by Mr. Griffing,
Major Ravenel,
F/Lt. F. R. Holt.
(Evaluation Report 139)
Dr. Kleen was head of the Telefunken Tube Research
Laboratories, recently at Berlin. Dr. Lerbs was in charge of the
Magnetron group under Dr. Kleen.

Most of the German centimeter tube development has been
made in these laboratories, which were for some time in
Liegnitz.
The first 10 cm. equipment. "Rotterdam" was operational
between 6 and 12 months ago; since then further marks of this
(known as X1 and X2) also "Berlin" and "München" have been
developed. The magnetron used, LMS 10, was a copy of the allied
one. The 3 cm. ones produced were claimed to be their own
development. The LMS 10 was 30% efficient. The LMS 100 up to 100
kW, also on 10 cm. was 10% efficient and had a field of 1500-
2000 Gauss, 30% greater than critical. It was air cooled and was
suitable for space/mark of 1000. The LMS 12 on 3 cm. had 18
splits, the L.M.S was 3 cm. tuneable, and water-cooled, with 2
kW loss. Small receiver magnetrons are the RD2MG (3 cm. 6 or 8
splits, 50 kW output, short life), the RD2MH, and the RD4MG,
This series contains about 10 other types. They have only used
Copper Magnetron anodes recently, have had trouble with glass
sealing (usually Nickel-iron soldered to the copper with Silversolder
was preferred), and have only recently found a
satisfactory method of pumping the LMS 100. For power
measurements up to 10 watts, they used the heating effect on a
resistance wire forming part of the Wheatstone bridge; above
that, water-flow methods.
Most of the tunable Magnetron work was done on 3 cm. They
used a metal ring supported on a flexible membrane and moved
towards the circle of gaps. Some magnetron development was done
by Sanitas GmbH, and possibly the Reichspost at Heidelberg. They
were produced by Telefunken at Berlin and Reichenberg in
Eulengebirge, and also by Sanitas and Getewent.
Most of the work on Klystrons was done in Prague by Dr.
Labos of the B.H.F., Telefunken have made 3 cm. all metal (that
is, main body) Klystrons and have been experimenting on 1 1/2
cms. These are reflected beam tubes. The following ceramic and
metal grounded-grid triodes have been made:-
LD7, LD9, LD11, LD13, LD70, LD90, LD110, a development of
LD10, LD120, LS1000, and a diode of similar construction
LG11. (They prefer however use a crystal detector up to
20 cm. LD12 was used in "Berlin", and LD11 in "Euclid" a
27 cm Navy equipment.
With the triodes they have obtained 10 kW peak power with a
space/mark from 5 to 10. This was of course in jammers. Names of
jammers mentioned were "Anti-Boomerang" i.e. Oboe "Anti
Rotterdam" i.e. H2S and any equipment with name beginning with
"Feuer" e.g. "Feuermolch" and "Feuer-Zauber". These jammers are
said to have been used operationally in small numbers (10 to 20
equipments.)"