M39 cannon
| M39 | |
|---|---|
| M39 cannon in the nose of a Brazilian F-5 | |
| Type | Single-barrel autocannon | 
| Place of origin | United States | 
| Service history | |
| In service | 1952–present | 
| Production history | |
| Designer | Ford Motor Company | 
| Designed | 1951 | 
| Manufacturer | Pontiac, Ford, FMC Corporation, and others | 
| No. built | 35,500+ | 
| Variants | M39, M39A1, M39A2, M39A3 | 
| Specifications | |
| Mass | 80.9 kg (178.5 lb) | 
| Length | 1.83 m | 
| Cartridge | 20×102mm | 
| Caliber | 20 mm (0.8 in) | 
| Barrels | Single barrel (progressive RH parabolic twist, 9 grooves) | 
| Action | five-chamber revolver | 
| Rate of fire | 1,500 rpm | 
| Muzzle velocity | 1,030 m/s (3,300 ft/s) | 
The M39 cannon is a 20 mm caliber single-barreled revolver cannon developed for the United States Air Force in the late 1940s. It was used on a number of fighter aircraft from the early 1950s through the 1980s.