'Crossbow' was a British intelligence and photo-reconnaissance campaign to learn about the development of German secret weapons at Peenemünde, an island in the southern part of the Baltic Sea just off the German coast, and then destroy the means of producing and launching such weapons (1943/44).
In a manner analogous to the 'Pointblank' offensive against the German aircraft industry, 'Crossbow' was dedicated to offensive and defensive countermeasures against the 'Bodyline' and 'Peenemünde 20', the British code names for the three-finned ballistic rocket (A-4 or V-2) and the small winged aeroplane (Fi 103 or V-1) which had been detected in reconnaissance photos.
On 15 November 1943 the codename 'Bodyline' was replaced by 'Crossbow' as the designation of all Anglo-US operations against all the phases of the German long-range weapons programme. Thus 'Crossbow' came to include operations against German research, experimentation, manufacture, construction of launching sites, and the transportation and firing of finished missiles, and also against missiles in flight.
After the first intimations had been received of the highly secret research and test work being undertaken by the Germans at Peenemünde, the initial offensive operation against this target was 'Hydra' (ii), in which Peenemünde was bombed on the night of 17/18 August 1943, and in overall terms the Allied 'Crossbow' offensive effort from August 1943 to March 1945 was 68,913 sorties for the delivery of 122,133 tons of bombs, of which 19,584 sorties and 72,141 tons of bombs were attributable to Air Chief Marshal Sir Arthur Harris’s RAF Bomber Command. The USAAF’s 8th AAF flew its first 'Crossbow' mission on 27 August, when 187 Boeing B-17 Flying Fortress bombers were despatched to attack the V-2 complex at Watten in German-occupied France.
As with the 'Chastise' dam-buster operation, the US characterised 'Crossbow' as a 'secondary campaign' or 'special enterprise' with the following effectiveness: the bombing of the launching sites being prepared for the V-weapons delayed the use of the V-1 appreciably, but the attacks on the V-weapons experimental station at Peenemünde were not effective; the V-1 was already in production near Kassel and the manufacture of the V-2 had also been moved to an underground factory.
The following statistics highlight the main features of the campaign against the V-1: 4,261 V-1 missiles were destroyed by fighters, anti-aircraft fire and barrage balloons. Hawker Tempest fighters shot down 638, de Havilland Mosquito fighters 428, Supermarine Spitfire Mk XIV fighters 303, North American Mustang fighters 232, and all other types combined 158. Anti-aircraft guns destroyed 95% of the V-1 missiles: 17% of all such weapons entering the coastal 'gun belt' were destroyed by guns in their first week on the coast, this figure increasing to 60% by 23 August and to 74% in the last week of the month, when on one day 82% were shot down. The rate improved from the initial figure of one V-1 destroyed for every 2,500 shells fired to one for every 100. About 100 V-1 missiles are claimed to have been destroyed by flying into balloon-supported barrages.