M24 cannon

M24 cannon. The M24 was an American-designed autocannon developed during the latter stages of World War II for use on aircraft. Intended as a lightweight aircraft cannon, it saw limited operational deployment before the conflict ended. Its design and development were influenced by the evolving demands of aerial warfare in the Pacific Theater.

Development and history

The development of the M24 was initiated by the United States Army Air Forces to address a need for a reliable, high-velocity 20 mm caliber weapon for fighter aircraft. The project was managed under the auspices of the Ordnance Department with involvement from several defense contractors. Design work progressed during 1944, with American Armament Corporation playing a key role in its production. Testing occurred at facilities like Aberdeen Proving Ground and involved comparisons with contemporary systems such as the Hispano-Suiza HS.404. The program concluded just as the Allies of World War II were achieving victory in both Europe and the Pacific, leading to its cancellation shortly after V-J Day.

Design and features

The M24 was a recoil-operated, belt-fed autocannon utilizing a 20×110mm USN cartridge. This ammunition was shared with the M3 cannon used on the Lockheed P-38 Lightning, promoting logistical commonality. A key design goal was reducing weight and complexity compared to earlier American designs like the M2 cannon. The weapon featured a relatively short barrel and a compact receiver, making it suitable for installation in aircraft wing pods or engine nacelles. Its firing mechanism was designed for synchronization to fire through the propeller arc of single-engine fighters, a common requirement for aircraft like the Republic P-47 Thunderbolt.

Operational use

Operational deployment of the M24 was extremely limited and it never entered widespread combat service. A small number were evaluated on modified North American P-51 Mustang and P-47 Thunderbolt airframes during trials conducted by the USAAF. These tests were part of broader efforts by units like the VIII Fighter Command to enhance firepower against hardened Japanese aircraft and ground targets. No records indicate its use in major engagements such as the Battle of Okinawa or the Bombing of Tokyo. The cannon was effectively rendered obsolete by the rapid post-war adoption of jet aircraft and newer weapons systems like the M39 cannon.

Variants

The primary variant was the basic M24, with no major sub-types entering production. A proposed development was an experimental model with a higher rate of fire, sometimes referenced in documents from Wright-Patterson Air Force Base. Post-war, some design elements and the ammunition were utilized in other projects, including early prototypes of gun pods studied by the United States Air Force during the Korean War. The 20×110mm USN round itself saw continued, albeit niche, use in certain aircraft cannon and anti-aircraft warfare systems during the early Cold War.

Specifications

* **Caliber:** 20 mm (0.787 in) * **Cartridge:** 20×110mm USN * **Action:** Recoil operation * **Rate of fire:** Approximately 600–700 rounds per minute * **Muzzle velocity:** ~2,700 ft/s (820 m/s) * **Feed system:** Disintegrating metallic link belt * **Length:** ~70 in (1.78 m) * **Weight:** ~90 lb (41 kg) * **Sights:** Adapted to standard USAAF reflector sights or gyroscopic gunsights

Category:World War II American aircraft weapons Category:Autocannon