[Col Bruggy]

Hello,

Air Launching (of V-1)

Automatic Launching Device ( Zaehlwerk).

Air-launching of flying bombs from Heinkel 'parents' or 'carrier' bombers was, in the main, carried out against London; but whatever the target for this means of attack, the problem was to put the 'carrier' into the correct position and on the correct bearing to release its bomb at a precisely calculated moment. Navigational aids were, in themselves, insufficiently accurate to determine the bomb release point and, to overcome this difficulty , each specially converted bomber carried an automatic timing device to ensure the highest possible degree of accuracy at launch. Great secrecy was maintained by the Germans over the whereabouts of bomb release points, which were constantly varied and known only to the observer and bombardier/navigator.

The instrument which determined the correct times for starting the bomb's motor, and for subsequently releasing the bomb, incorporated a tachometer and was attached to the pilot's upper instrument panel where it could also be seen by the observer. Known as the Zaehlwerk, it incorporated a small display panel with five or six digits. These also appeared on a repeater box for the bombardier/navigator, together with two push-buttons coloured black and red: a lever beneath the repeater box released the bomb. At the beginning of the flight, he would move a switch at the left hand side of the unit causing the counter to run down by single units, a sequence which took about twenty minutes. When the counter reached zero, the bombardier/navigator released the bomb.

Once the Zaehlwerk had been started, there was nothing for the bombardier to do until the figure 100 had been reached. At this pont he received a warning from the observer to get ready. When the counter reached the figure 23, the bombardier/navigator pressed the black button, or 'Austellknopf', which ignited the bomb's motor whose vibration and noise could be heard in the 'parent' aircraft. When the counter reached 0, (some ten seconds later), the bombardier/navigator pulled the lever beneath the repeater box to release the bomb.

In case of premature ignition, the motor could be cut by pressing the red button, or 'Abstellknopf'. If it became necessary to jettison the bomb, this operation was carried out by the pilot who pulled the red painted lever above his head.

See:
The Flying Bomb.
Young,Richard Anthony.
London:Ian Allan,1978.
p.150 (Appendix 9).

Col.