| HS.404 | |
|---|---|
 HS.404 in the TCM-20 twin anti-aircraft configuration, displayed at the Israeli Air Force Museum | |
| Type | Aircraft cannon |
| Place of origin | Switzerland France |
| Service history | |
| Wars | |
| Production history | |
| Designer | Marc Birkigt |
| Manufacturer | Hispano-Suiza |
| Specifications | |
| Mass | 49 kg (108 lb 0 oz) |
| Length | 2.52 m (8 ft 3 in) |
| Barrel length | 1.7 m (5 ft 7 in) |
| Cartridge | 20×110mm |
| Calibre | 20 mm (0.79 in) |
| Action | Gas operated[1] |
| Rate of fire | 700-750 rounds/min |
| Muzzle velocity | 840–880 m/s (2,800–2,900 ft/s) |
| Feed system | Drum magazine, belt (later models) |
| 20 mm M1 automatic gun | |
|---|---|
| Type | Aircraft cannon |
| Place of origin | United States |
| Service history | |
| In service | United States Army Air Forces |
| Used by | United States |
| Wars | |
| Production history | |
| Manufacturer | International Harvester |
| Produced | 1941 – April 1942 |
| Variants | A/N M2, A/N M3, M24 |
| Specifications | |
| Mass |
|
| Length | 2.54 m (100 in) |
| Barrel length |
|
| Cartridge | 20×110mm Hispano "A" |
| Calibre | 20 mm (0.79 in) |
| Action | Gas operated, delayed blowback[1] |
| Rate of fire | 650–700 rounds/min |
| Muzzle velocity | 870 m/s (2,900 ft/s) |
| Maximum firing range | 6,500 m (7,000 yd) |
| Feed system | 60-round M1 drum or linked belt |
| Hispano Mk.V | |
|---|---|
 20 mm Hispano-Suiza Mk V on display at the Imperial War Museum Duxford | |
| Type | Aircraft cannon |
| Place of origin | United Kingdom |
| Service history | |
| Used by | United Kingdom & British Empire, Commonwealth, United States |
| Wars | |
| Specifications | |
| Mass | 38 kg (83 lb 12 oz) |
| Length | 2.184 m (7 ft 2.0 in) |
| Barrel length | 1.333 m (4 ft 4.5 in) |
| Cartridge | 20×110mm |
| Calibre | 20 mm (0.79 in) |
| Action | Gas operated, delayed blowback[1] |
| Rate of fire | 700-750 rounds/min |
| Muzzle velocity | 840 m/s (2,800 ft/s) |
| Feed system | Belt |
The HS.404 is an autocannon originally designed by and produced by the Swiss arm of the Spanish/Swiss company Hispano-Suiza in the mid-1930s. Production was later moved to the French arm of Hispano-Suiza.
It was widely used as an aircraft, naval and land-based weapon by French, British, American and other military services, particularly during World War II. The cannon is also referred to as Birkigt type 404, after its designer Marc Birkigt and later versions based on British development are known as 20 mm Hispano.[2]
Firing a 20 mm calibre projectile, it delivered a significant load of explosive from a relatively light weapon. This made it an ideal anti-aircraft weapon for mounting on light vehicles, as well as a fighter aircraft gun, supplementing or replacing the 7.62 mm (.30 calibre) and .303 inch (7.7 mm) machine guns commonly used in military aircraft of the 1930s. The HS.404 was produced by the French subsidiary of Hispano-Suiza, and under license by a variety of companies in other countries.
- ^ a b c "Hispano-Suiza 20mm Cannon". The Pacific War Online Encyclopedia. Retrieved 2015-12-30.
- ^ Chinn, George M. (1951). The Machine Gun: History, Evolution, and Development of Manual, Automatic, and Airborne Repeating Weapons. Vol. I. Washington, D.C.: U.S. Government Printing Office. pp. 562–590. Retrieved 2010-07-28.