The Fi 103 is also known as the V1 (Vergeltungswaffe 1, Retaliation Weapon 1), the first of the "secret weapons" that was expected to turn the war in favor of the Germans in 1944. Over 30,000 of these flying bombs with a warhead of 1,874 lb (850 kg) were produced until March 1945.
Hitting London for the first time on June
13, 1944, the projectiles were ground and air-launched. The RAF
intercepted 1,771 V1's, the Hawker Tempest Mk.V scoring over
one-third. Later the flying bombs were aimed also at other targets
such as the ports of Antwerp in Belgium.
However, many thousands
malfunctioned during or after launch, or were destroyed by the Allied
forces therefore not reaching the intended targets. The V1 had the
codenames Kirschkern (Cherry Stone) and Flakzielgerät (Flak
Target Device) 76 (FZG 76). Flak was the abbreviation for
Flugzeugabwehrkanon (anti-aircraft canon.)
A manned V1 was also
intended, the Fi 103 R of
which 175 were produced, however never reaching operational status.