||The V-1 was a small pilotless aircraft, fitted with an 850 kilogramme high explosive warhead and powered by a petrol-fuelled pulse jet engine. It was the first of Germany's "vengence weapons" or vergeltungwaffen, from which the "V" designation was derived, although its correct designation was the FZG-76. Development work on the FZG-76 began at Peenemünde in June 1942 and the first successful flight took place on 24 December 1942. Mass production began on 1 March 1944 and about 35,000 were eventually produced.
The FZG-76 was launched from an inclined ramp and it was originally intended to be fired from hardened fixed launch sites. These sites, however, were hard to conceal and as a result were heavily attacked by Allied aircraft. Most operational launches of the FZG-76 were thus conducted from portable launch ramps that were concealed amongst buildings and vegetation. The first occurred on 13 June 1944 and was targeted on London. Up until 29 March 1945, 9,521 FZG-76s were launched against targets in the United Kingdom, of which only 6,725 made it as far as the British coast and 4,621 were subsequently destroyed by anti-aircraft fire or fighter aircraft, leaving to 2,104 to crash down somewhere, not always on their intended target. The main launch sites were located in the Pas de Calais in France, but once these were overrun by Allied forces in September 1944, FZG-76s were launched from Heinkel III bombers up until January 1945. The last phase of the flying bomb offensive on Britain was conducted between 3 and 29 March 1945 with a long range variant of the FZG-76, launched from sites in Holland. Six and a half thousand FZG-76s were also launched against Dutch and Belgian towns, predominantly Antwerp; 4,096 of which reached their targets.