Which 30 mm cannon is internally mounted in the A-10 aircraft?

The GAU-8/A is the correct choice, as it is specifically designed for the A-10 Thunderbolt II, commonly known as the A-10 Warthog. This cannon is a 30 mm rotary cannon that plays a crucial role in the aircraft's capabilities, primarily for close air support and ground attack missions. It features high firepower, allowing it to engage a variety of targets, including armored vehicles.

The GAU-8/A has a high rate of fire and uses special ammunition designed for effectiveness against various targets, making it particularly suited for the A-10's mission profile. Its internal mounting allows the A-10 to carry a significant amount of ammunition and maintain a streamlined design, essential for its operational effectiveness.

Other types of cannons, like the M61A1, are used in different aircraft but are not mounted on the A-10. The GAU-12/U and M230 Chain Gun are also used in other platforms, further distinguishing the GAU-8/A as the unique cannon associated with the A-10.