F35 Lightning II Variants

The F-35 is planned to be built in three different versions to suit the needs of its various users.

F-35A

The F-35A is the conventional takeoff and landing (CTOL) variant intended for the US Air Force and other air forces. It is the smallest, lightest F-35 version and is the only variant equipped with an internal cannon, the GAU-22/A. This 25 mm cannon is a development of the GAU-12 carried by the USMC's AV-8B Harrier II. It is designed for increased effectiveness compared to the 20 mm M61 Vulcan cannon carried by other USAF fighters.

The F-35A is expected to match the F-16 in maneuverability and instantaneous and sustained high-g performance, and outperform it in stealth, payload, range on internal fuel, avionics, operational effectiveness, supportability, and survivability. It also has an internal laser designator and infrared sensors, equivalent to the Sniper XR pod carried by the F-16, but built in to remain stealthy.

F-35B

The F135 engine with lift fan, roll posts, and rear vectoring nozzle, as designed for the F-35B, at the Paris Air Show, 2007.

The F-35B is the short takeoff and vertical landing (STOVL) variant of the aircraft. Similar in size to the A variant, the B sacrifices some fuel volume to make room for the vertical flight system. Takeoffs and landing with vertical flight systems are by far the riskiest, and in the end, a decisive factor in design. Like the AV-8B Harrier II, the B's guns will be carried in a ventral pod. Whereas F-35A is stressed to 9 g, the F-35B is stressed to 7 g. Unlike the other variants, the F-35B has no landing hook; the "STOVL/HOOK" button in the cockpit initiates conversion instead of dropping the hook.

F-35C

The F-35C carrier variant has a larger, folding wing and larger control surfaces for improved low-speed control, and stronger landing gear and hook for the stresses of carrier landings. The larger wing area allows for decreased landing speed, increased range and payload, with twice the range on internal fuel compared with the F/A-18C Hornet, achieving much the same goal as the heavier F/A-18E/F Super Hornet.