German success against the Nijmegen and Remagen bridges.

[Nick Beale]

Originally Posted by tcolvin

Thank you for the information, Nick; much appreciated.

I would also appreciate information about how the German jets bombed under EGON guidance, and the accuracy obtainable by their version of Oboe/GEE-H?

Tony

Ultra CX/MSS/T485/1:

Signed Jedele, Fhr., at 1600 hours 9th [March 1945]:-
Employment with III./KG 76 from 1(B% 4) 15 – 1545 hours on 9th, attack on Remagen bridge. Leading a/c £ Führermaschine £ was directed into the target area and to the point of dive though cloud £ Durchstosspunkt £.

NOTE:- Jedele controls Egontrupp Achmer (473/87)

BA-MA RL2 II/118: «Gen.Nafü (1.Abt.II) Vortragsnotiz betreffend Egon-Führung für Nachtschlachteinsätze auf Brücke und Brückenkopf Remagen» says that with good crews, accuracies of plus or minus 200m in range and 0.25 degrees in bearing were attainable.

[SES]

Originally Posted by tcolvin

Thank you for the information, Nick; much appreciated.

I would also appreciate information about how the German jets bombed under EGON guidance, and the accuracy obtainable by their version of Oboe/GEE-H?

Tony

Hi Tony,
This may partly answer your Freya-EGON question.
http://www.gyges.dk/II%20JK%20spring%201945%202.htm

As a side note. This method was nowhere as accurate as Oboe.
bregds
SES

[tcolvin]

Thank you Nick and SES.
Is the following conclusion accurate?
Conclusion;
- the AR234 B-2s carrying 1-ton bombs of IIIKG76 flew from Burg, located NE of Magdeburg, with fuel for a 760km round trip from Remagen.
- an An722 Zyklop directional beacon, consisting of a trailer with an AS 3 Funklandesender and two masts located 14m apart pointing directly at Remagen bridge, was set up presumably either at Codename Dornröschen (at 53639 Petersberg near Königswinter) about 12km due north of the Remagen Bridge, or at Codename Rübezahl (at 56584 Rüscheid), about 20km southeast of Remagen, and linked to an FuBl 1 or 2 Funklandegerät carried presumably only on the Führermaschine (leading Ar234 B-2 per Nick's Enigma decrypt).
- The pilot (sole crewmember) observed a course deviation indicator in front of him and corrected accordingly. Presumably, per Nick's Enigma decrypt, this was on the Führermaschine only but there seems no reason why course correction was not available to every pilot on the raid.
- The pilot of the Führermaschine was informed in real time by W/T of distance to target. This was obtained through EGON (Erstling-Gemse-Offensive Navigationsverfahren), being the normal German IFF (Freund-Feind Kennung) comprising the Erstling Kenngerät FuG 25a on the Ar234 B-2 responding automatically to the Gemse Freya FUS An 730 (Freya EGON). Presumably the other pilots on the raid received the same distance-to-target information and knew it applied specifically to the position of the Führermaschine. Distance-to-target was derived manually by plotters using a map (am I right?)
- The Gemse Freya in use was presumably one or other of those at Codename Dornröschen or Codename Rübezahl.
- The pilot of the Führermaschine flew the course that would take him over Remagen Bridge, and would initiate his attack as soon as W/T informed him of his arrival at the Durchstosspunkt (point of dive) which could be in cloud per the Enigma decrypt supplied by Nick. At this point he would call the German equivalent of 'Tally-ho', and dive for the bridge followed by the others on the raid. Bomb release in the dive was controlled by the pilot, AFAIK. But since it was a shallow dive delivering a single one-ton bomb, into heavy radar-directed and manually-aimed Flak, with the pilot sitting in a glasshouse with a superb view but feeling as vulnerable as hell, the system's accuracy came down to human skill and bravery. The Zyklop got him to the dive point on the right target heading.

This was German state-of-art bridge destruction at the end of the war, and should be compared and contrasted with its Allied equivalent.
What exactly was the Allied equivalent is unclear.
RP Typhoon 2s were not used against the Wesel bridges for reasons unknown, although speed in the shallow dive and hitting power were either the same or superior to the Ar234 B-2, and vulnerability to Flak was identical.
Bomphoons either uncontrolled or controlled by MRCP while flying straight and level outside the reach of medium Flak were not used against the Wesel bridges for reasons unknown.
Mosquitoes controlled by Oboe while flying straight and level at night above medium Flak were used against the Wesel Bridges.
B-17s bombing visually from height were used against the Wesel Bridges.

This provides confirmation that no sure weapon system for bridge destruction in 1945 existed in the GAF or RAF/USAAF. Russian equivalents are unknown.

Tony

[SES]

Hi Tony,
You are not far off the mark, but I think bomb release was done in level flight - with a CEP of 1.000 m .
And there was no sure way of destructing a bridge until the advent of the laser or GPS guided bombs, provided the bomb is big enough.
bregds
SES

[Nick Beale]

Dornröschen = Sleeping Beauty, I think.
Rübezahl = is also a fairy tale character but I don't think there's an English (or Disney?) equivalent.

[tcolvin]

Originally Posted by SES

Hi Tony,
You are not far off the mark, but I think bomb release was done in level flight - with a CEP of 1.000 m .
And there was no sure way of destructing a bridge until the advent of the laser or GPS guided bombs, provided the bomb is big enough.
bregds
SES

Please explain "a CEP of 1.000 m".

Actually this is a reminder that there were three bombing techniques available on the Ar234 B-2.
a) shallow dive using the PV1B periscopic sight with the on-board BZA bombing computer, which presumably released the bomb/s automatically
b) under autopilot with the aircraft aimed at the target using the Lotfe bombsight which was integrated with the bombing computer that released the bomb/s automatically. I read that this method was not popular.
c) what is called the EGON flight control (sic) system using the FuG 25a IFF transceiver in conjunction with two Gemse-Freyas. Presumably the pilot dropped the bomb when told to by the controller over the W/T.
Well, two suitable Gemses existed, and theoretically also two Zyklops, on the hills at Petersberg and Rüscheid, which were almost in line of sight of Remagen bridge which could therefore be accurately 'painted'. But even if the target was accurately identified, there was no way of delivering a bomb onto it from a fast moving aircraft.

The conclusion must be that in 1945 the only certain way of hitting a pin-point target was either to go in vertically or to send sufficient bombers with sufficient bombs of sufficient size to make it statistically highly likely that one would hit the bridge. This presumably was how the Seine bridges were brought down by BC/VIIIUSAAF in the Transportation Plan.
I have found a reference to Mitchells bombing the Wesel bridges under MRCP, which I will summarise in the RAF section. It was no more accurate than AR 234 B-2s under EGON.
The GAF, however, had the means of going in vertically with the Ju-87, but these were shot out of the skies by Flak, as was the Ar234 B-2. Increasing top speed did not solve the Flak problem, although it might have reduced it, but increasing top speed made the pilot more reliant on mechanical bombing aids, which in 1945 were unreliable.
Flak suppression was the missing ingredient.

Tony

[Nick Beale]

"Please explain "a CEP of 1.000 m".

CEP = Circular Error Probability = the radius of a circle around the aiming point within which a given percentage of the bombs/missiles/whatever will fall (usually 50%).

"The GAF, however, had the means of going in vertically with the Ju-87"

Actually, they may not have done. As photos show, the Ju 87s of the Nachschlachtgruppen frequently had their dive brakes removed (albeit not always). Their night attacks were generally conducted in level flight or a shallow dive - I'd imagine vertical dives at night are not a good idea - and so the brakes were just extra weight and drag.

[Khorat]

hm somewhere had a pic, of a bomb just released by a Ar 234 taken from the pilot of the plane, over the ponton bridge at Linz - few meters north of the remagen bridge, its a priv. pic, so no height given - but think was not higher than about 800 - 1000 meters and in a shallow dive.
khorat

[NickM]

Originally Posted by Nick Beale

Dornröschen = Sleeping Beauty, I think.
Rübezahl = is also a fairy tale character but I don't think there's an English (or Disney?) equivalent.

Maybe the second one is Rapunzel? With the golden hair?

NM

[Nick Beale]

Originally Posted by NickM

Maybe the second one is Rapunzel? With the golden hair?

NM

I looked the name up on Google Images - he's not so pretty!