The Vergeltungswaffe l (the revenge, or retaliation, weapon), or V1, had a plethora of names. To the Luftwaffe, it was the Fliegerabwehrkanonezielgerät 76 (Flakzielgerät 76, or just FZG 76), but that was a cover-name: Fliegerabwehrkanonezielgerät means ‘anti-aircraft gun aiming device’ or conceivably ‘antiaircraft gun target device’. Its official codename was ‘Kirschkern’ (‘Cherrystone’) and it was also known as ‘Krahe’ (‘Crow’); while to the RLM it was the Fi 103; and to the airframe manufacturers, Fieseler, it began life as P. 35. To the British public it was the Buzzbomb, the P-Plane or the Doodlebug, while the RAF knew it as ‘Diver’. In effect a first-generation cruise missile, it was an unmanned air-breathing jet aircraft with an explosive warhead and a simple guidance/targeting device.

The Fieseler Fi 103 A-1, the original and technically most common version of the flying bomb, was about 8m (26ft) long. Its wingspan was of around 5m (17ft) although there were two different wings produced in slightly different form and dimensions, and it had a maximum fuselage diameter of 0.84m (2.75ft); the warhead comprised 830kg (18321b) of Trialen (amatol), which was sometimes supplemented by incendiary bombs. Provision was made to replace the explosive with gas, though this never happened in practice. A full load of 75-80 octane fuel added 515kg (11331b) to the all-up launch weight total of 2180kg (48061b). It had an autonomous range of 240km (150 miles) at a maximum speed of 645km/h (400mph), and an operational ceiling of 3000m (9800ft). It was fabricated from sheet steel pressings, with an aluminium nosecone and sheet-steel wings around a single tubular steel spar. The emphasis was on keeping costs to a minimum, and little effort was put into reducing weight by employing more exotic materials. In 1945, the Fi 103 F-l was produced. Basically similar to the A-l, its warhead contained 436kg (9621b) of amatol, and its fuel tanks were enlarged from 568 litres (125 gallons) to 756 litres (166 gallons), increasing range to 370km (230 miles).

The V1 was very cost-effective, even if it was at best only 20 per cent effective. Estimates of the unit cost vary, but around 5000 Reichsmarks seems reasonable at a time when the standard German infantry rifle, the Mauser 98K, was costing RM56, and a PzKpfw IV tank over RM 100,000.

An aspect of the V1 operational story is frequently overlooked. The Germans also launched about 7,400 to 9,000 V-ls against targets on the continent, mostly (4,900) against the port of Antwerp, Belgium. In the city’s defense the Allies deployed 18,000 troops manning 208 90-mm guns, 128 3.7-inch guns, and 188 40-mm guns. In addition, they used 280 balloons later augmented to 1,400. No fighters were employed in the defense of Antwerp. In the attack on Antwerp, the Germans deployed their first missiles from the southeast. In mid-December, they shifted to the northeast and finally, by the end of January, to the north. The last direction of attack created a particular problem for the defense because a large airfield in that sector was not closed until 21 February 1945. Nevertheless, the defenders downed 2,183 (91 .2 percent) of the 2,394 missiles plotted. More to the point, only 211 V1 s reached a 7,000-yard radius area around the docks that the defenders designated as the vital area.

The Germans also attacked Liege, Belgium, with about 3,000 V1 s. It was defended between 23 November and 11 December 1944, when the urgent needs of the Battle of the Bulge pulled the defenders out.

V1s killed a total of 947 military and 3,736 civilians and wounded 1,909 military and 8,166 civilians on the continent. Antwerp suffered 1,812 military and 8,333 civilian casualties, or 10,145 of the 14,758 V-1 casualties on the continent.