20 mm Becker

The 20 mm Becker was a German automatic cannon developed for aircraft use during World War I. It was first mass produced in 1916 and was installed in a variety of aircraft; the only German autocannon to actually see service in the air during the war.

Development commenced in 1913 and was therefore already advanced when the War Ministry issued a specification in June 1915 calling for an aircraft cannon of under 37 mm caliber and 70 kg weight capable of firing a 10-round burst. Tests commenced shortly thereafter with the weapon mounted in a Gotha G.I, but proved unsatisfactory. Despite this, the potential of the gun was such that the arsenal at Spandau was engaged to help develop and fine-tune the design, leading to a production contract for 120 Becker Type M2 guns in June 1916. In addition to the orders for aircraft guns placed with Becker, Spandau and MAN also received a contract to build Becker cannon for the Army.

The 20-mm Becker was a slim weapon working on the principle of advanced primer ignition blowback. It weighed only 30 kg. It was fed by a somewhat awkward, curved box magazine, available in versions that held 10 or 15 rounds; the latter weighed another 5 kg. As the rate of fire was 325 rounds per minute, this magazine could be emptied very quickly. The muzzle velocity was 490 m/s, which was low compared to the rifle-calibre machine guns of the period such as the German MG 08, but a respectable performance compared to other automatic cannon of the period, such as the Vickers "pom-pom".

The main types to utilise the Becker were large aircraft - the Friedrichshafen G.III bomber and AEG G.IVk ground-attack machine. Tests in smaller, single-engined aircraft were not so successful, but were carried out extensively through the rest of the war, commencing with an Albatros J.I in December 1917. Due to the gun's operating principles, it could not be synchronised, and this posed an immediate problem for its installation in this type of plane. The solution adopted after the tests with the Albatros J.I was to fit it to fire downwards through the floor. Fitting the gun to a fighter with a pusher configuration was another obvious solution, and trials were carried out with an Albatros D.VI. Other intended installations were for an AGO C.I and the Hansa D.I, but these were not carried out before the Armistice.

Total production figures are not known, but were in excess of 539. A total of 362 were surrendered to the Allies.

The patent for the gun was bought by SEMAG in 1921, who continued development with a more powerful cartridge, and then by Oerlikon in 1924, who marketed improved versions as the Oerlikon F, L and S.

Applications

• Friedrichshafen G.I
• AEG G.IV
• AEG J.II
• AGO S.I
• Albatros D.II
• Albatros D.VI
• Albatros J.I
• Caspar D.I
• LVG C.V

See also

• Oerlikon 20 mm cannon-development of the Becker design in Switzerland after WWI.
• MG FF cannon-the final German World War II development of the Becker design.

References

• Grosz, P. "The 2 cm Becker Aircraft canon - development and use." Over the Front 7 (2).
• Williams, Anthony G. and Emmanuel Gustin. (2004) Flying Guns of World War I. Ramsbury: The Crowood Press.
• Williams, Anthony G. (2000) Rapid Fire Airlife, UK.