Offered here is a 20mm M39 Revolver Cannon Gear Box Motor, part number JFB-D300-2, in new old stock condition. This original U.S. military component was engineered to drive the mechanical systems of the M39 20mm aircraft revolver cannon, a widely used American autocannon system originally developed during the 1950s and fielded extensively during the Cold War.

The gear box motor played a critical role in maintaining the cannon's high rate of fire by driving the rotation of the chamber and feeding mechanisms. Designed to be electrically driven, this motor features robust internal gearing and precise manufacturing tolerances to meet the high-performance requirements of aircraft-mounted armament systems.

Historical Significance of the M39 Cannon System

The M39 20mm revolver cannon was developed by the U.S. Air Force as an improvement over World War II-era aircraft guns. It was chambered for 20x102mm ammunition and capable of firing at a rate of approximately 1,500 rounds per minute. The M39 became the primary armament for a variety of U.S. aircraft in the 1950s and 1960s, including the F-86 Sabre, F-100 Super Sabre, F-101 Voodoo, and F-5 Freedom Fighter.

While later replaced in most applications by the multi-barrel M61 Vulcan, the M39 remains an important part of American aerial armament history and served as a platform for engineering the next generation of high-speed autocannons. Gearbox motors like this were critical to sustaining the system's fire rate and reliability under high-G and high-vibration flight conditions.

Product Details

Item: Gear Box Motor for 20mm M39 Revolver Cannon
Part Number: JFB-D300-2
NSN: 1005-00-211-8328
FSN: 1005-211-8328
Condition: Military surplus
Application: Used to drive mechanical systems in the M39 aircraft cannon

Ideal For:

Aircraft armament restorers and collectors
Cold War aviation museums and exhibit builders
Military surplus part resellers
Technological historians studying U.S. aerial weaponry
Static and functional aircraft cannon display restorations

This M39 Gear Box Motor is a rare opportunity to own a hard-to-find U.S. aircraft cannon component, ideal for restoration, display, or spare parts inventory. With limited quantities remaining in military surplus, this is a must-have for aviation ordnance collectors and Cold War historians.

Approx length 5", Approx width 2.5", Approx height 4", Approx weight 2lbs.

Pictures are stock images of our inventory. Unless otherwise noted, you will not be receiving the exact item shown in the pictures. The pictures are representative of the item's general condition. The item you receive might be slightly better, or worse, condition than was shown in the pictures.

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