Why does the F-35 carry a different gun instead of the original Vulcan?

Why does the F-35 carry a different gun instead of the original Vulcan? The F-35 Lightning II carries a different gun, the GAU-22/A, instead of the older M61 Vulcan for several reasons, largely revolving around design efficiency, technological advancements, and mission requirements. Here’s a breakdown of the rationale:

Weight and Size

The GAU-22/A is a lighter, more compact four-barrel 25mm rotary cannon. In comparison, the M61 Vulcan is a six-barrel 20mm rotary cannon, which is heavier and takes up more space. The F-35’s design prioritized minimizing weight and space due to its role as a stealth fighter, so a lighter gun helped meet those requirements.

Stealth Design

The F-35A (conventional takeoff and landing version) houses the GAU-22/A internally to maintain its stealth profile. The smaller design of the gun aids in keeping it concealed within the aircraft’s fuselage, whereas the larger M61 Vulcan would pose a challenge in maintaining the same level of radar cross-section reduction.

Increased Firepower

The GAU-22/A’s 25mm rounds provide greater destructive power compared to the 20mm rounds used by the M61 Vulcan. This increase in firepower aligns better with the F-35’s multirole mission, giving it more effective capabilities in both air-to-air combat and air-to-ground engagements.

Reduced Barrel Count

The GAU-22/A has four barrels compared to the Vulcan’s six, which reduces overall weight and complexity. It still delivers a high rate of fire (up to 3,300 rounds per minute) but with greater accuracy and efficiency for modern combat needs.

Advancements in Avionics

The F-35’s advanced targeting systems and fire control are optimized for the GAU-22/A. With modern avionics, fewer rounds may be needed to achieve a successful hit, further making a higher volume weapon like the Vulcan less necessary.

In summary, the GAU-22/A was selected to align with the F-35’s stealth, weight-saving, and mission versatility requirements while providing more powerful munitions in a smaller package.