The Lockheed Martin F-35 Lightning II is a family of single-seat, single-engined, all-weather stealth multirole fighters. It has three main models: the F-35A conventional takeoff and landing (CTOL) variant, the F-35B short take-off and vertical-landing (STOVL) variant, and the F-35C carrier-based catapult-assisted take-off but arrested recovery (CATOBAR) variant. The F-35 descends from the Lockheed Martin X-35, the winning design of the Joint Strike Fighter (JSF) program. It is built by Lockheed and many subcontractors, including Northrop Grumman, Pratt & Whitney, and BAE Systems.

The United States principally funds F-35 development, with additional funding from other NATO members and close U.S. allies, including the United Kingdom, Italy, Australia, Canada, Norway, Denmark, the Netherlands, and Turkey. These funders generally receive subcontracts to manufacture components for the aircraft; for example, Turkey is the sole supplier of several F-35 parts. Several other countries have ordered, or are considering ordering, the aircraft.