The first ideas of a missile similar to the V1 eventually developed by Germany date back to the end of he First War when Rene Lorin, a French artillery officer, suggested that long ranged missiles should be developed for attacking objectives such as Berlin; he proposed a pilotless aircraft stabilized by gyroscopes, propelled by a ram jet or pulse-jet and guided by radio from a master-aircraft.
Work on pulse-jet engines started as early as 1907 when Victor de Karavodine filed a patent for a pulse-jet. A few years later, Georges Marconnet patented a whole series of jet-propulsion systems. The German pulse-jet, developed between the wars, was probably an independent invention although possibly influenced by the early work of de Karavodine and Marconnet.
Two rival pulse-jets were developed in Germany, the Schimdt duct and the Argus duct. Schimdt suggested as early in the 1930’s that the engine should be used to propel a ‘flying torpedo’. However it was Argus who was invited just before the outbreak of War to come up with a design for a pilotless missile with a range of 350 miles.
At the same time the Army began planning for a long range rocket along the lines of what would become the A4 rocket. This idea had been raised as early as 1923 when Herman Oberth suggested a long range rocket propelled by liquid fuels may be used to offset a lack of artillery, a result of the Treaty of Versailles.
The idea did not really move any further during the early years of the war, but the new programme of Allied fire-raising, tried out at Lubeck on 28 March 1942 with more than 200 acres of buildings destroyed, incensed Hitler and he ordered ‘terror attacks of a retaliatory nature’. The ‘Baedeker’ raids which followed, did some damage but the Luftwaffe was not the force it was in 1940. It was an opportunist time to push forward the idea of the pilotless missile. The Luftwaffe was looking for new ways to hit back at Britain.
An engineer, Robert Losser, who worked for Fieseler, was keenly interested in the Argus project, and suggested a partnership – Argus was essentially an engineering firm while Fieseler were experienced designers and manufactures of aircraft. A third firm, Asakania, was brought into the partnership to work on the control mechanism. After a meeting with the Air Ministry on 19 June, Milch, who combined the roles of Inspector-General of Luftwaffe, Director-General of Equipment and secretary of State for Air, ruled that the highest priority should be given to the development of the missile.
The missile was known at first as the Fieseler 103 but soon renamed as the FZG 76 (Flakzielgerat or anti-aircraft apparatus) in an attempt to deceive the enemy. The name Vergeltungswaffe 1 (Reprisal Weapon) hence V1 only came into use after the missile was brought into service. It also became to be known as the flying bomb, buzz bomb and doodle-bug by the British.
Trial launchings of the A4 (Vergeltungswaffe 2) rocket began in June 1942. The first pilotless missile was launched from an aircraft in December 1942. At first the V1 and V2 were regarded as alternative rather than complementary weapons but preparations went ahead to prepare both to be ready for Christmas 1943.
Work was well underway for mass production of the V1 by the summer of 1943 but was delayed by the problem of when to decide to finalize the design and move to from testing to production (a problem with all new technology). A further delay occurred when the Fieseler works at Kassel became a top aircraft factory priority for Allied bombing. This resulted in a delay of the limited-production models for testing.
Preparations still continued for the expected Christmas launch of 1943 with the formation of a higher command for the programme and a unit (Flakregiment 155) raised for the launch of the FZG 76. Work was begun on the construction of 96 launch sites. These sites consisted of a ramp from which the missile would be catapulted from along with concrete command and storage buildings. In addition, massive concrete structures were prepared at Siracourt and Lottinghem as sites where launching could take place in the worst of conditions. Another building at Equeurdreville, at first intended for the A4 rocket, was also added to these two sites.
In December 1943, General Heinemann assumed overall responsibility for active operations of both the FZG 76 and A4. With regards to the FZG 76 launch sites already constructed, he soon realized they would be obvious targets for Allied bombing and ordered that new sites be found, of a simpler design and less distinctive pattern. Work was to continue on the existing sites as decoys only. It also became obvious that the A4 rocket would probably be not ready until the summer of 1944 let alone Christmas 1943.
The offensive was finally launched on 13th June 1944, with a single FZG 76 landing in the village of Swanscombe.
British search for the Secret Weapons
Although the British were aware that the Germans had an interest in rockets prior to the outbreak of war, it was not until November 1939 that the first intelligence was received that Germany was planning to use long range missiles for war purposes. However little was done with this information until further reports from agents confirmed that Germany had held trials of a long range rocket at Swinemunde at the end of 1942 – further reports linked these trials specifically to Peenemunde.
The search for these weapons was at first confused by the form that British experts expected them to take. A 60-ton rocket with a 10-ton war head was envisaged and searches made for massive sites capable of launching such a weapon. As a matter of fact the A4 rocket only weighed 13 tons including a full load of fuel.
Early in 1943, further intelligence was received of the experimental station at Peenemunde and in June 1943 intelligence was received of a secret weapon to be used against London, ‘an air-mine with wings, long-distance steering and a rocket-drive’. By August 1943, evidence was now pointing to two distinct weapons – the A4 rocket and a winged missile. By October 1943, reports were received of buildings being erected, probably for secret weapons. Aerial reconnaissance of these sites showed a standard layout of concrete buildings along with a concrete slab, with a small concrete hut at one end and a row of concrete studs at the other, another square building with a 22 ft opening across one side of the slab; and a small number of concrete buildings, curved in plan at one end. These sites became known as ski sites due to the curved concrete buildings resembling skis.
The picture was still confused though. The purpose of the ski sites was unknown and there was no evidence of the supposed 60-ton rocket. It was Section Officer Babington Smith, W.A.A.F officer in charge of Aircraft Section of the Central Interpretation Unit tasked with studying aerial photographs, who made the break through when she identified midget aircraft at Peenemunde on November 13th. On November 28th, an aerial photograph clearly showed one of these midget aircraft sat on a ramp at Peenemunde as well as a ramp built on the concrete slab of a ski site at Zinnowitz.
By November 1943, 95 ski sites had been identified. It was assumed that the curved concrete buildings could store components for 20 missiles at each site which could be replenished daily. An attack of up to 2,000 missiles a day was assumed likely if Germany was allowed to complete the preparation of these sites. In December, Allied bombers began to attack these ski sites, but the decision had been taken by General Hienemann to abandon these sites in favour of modified and less conspicuous sites.
Allied bombers dropped 3,000 tons of bombs on ski sites during December 1943 and a further 20,000 tons between 1st January and 12th June 1944. It was believed that the pilotless programme had been severely disrupted. By the time firm intelligence was received of the new modified sites, the Allied landings in Normandy were only weeks away and the Allied Expeditionary Air Force attached little importance to them. As a result the modified sites were not attacked in May and June. Perhaps to justify this lost opportunity, after the War Marshal Harris claimed the Germans were planning to launch 6,000 flying bombs per day from the ski sites and that Allied bombing of these had forced the Germans to use ‘a much less efficient site’.
The Defence of the United Kingdom, B Collier, HMSO, 1957
The Battle of the V- Weapons, B Collier, The Elmfield press, 1964