The Kellett XR-10 was a military transport helicopter developed in the United States in the 1940s that only flew in prototype form.

It was designed in response to a USAAF Technical Instruction issued for the development of a helicopter to transport passengers, cargo, or wounded personnel within an enclosed fuselage.

The XR-10 resembled a scaled-up XR-8, although its twin engines were carried in nacelles at the fuselage sides, driving the rotors via long driveshafts, and the aircraft was skinned entirely in metal.

The first of two prototypes flew on 24 April 1947, and at the time, was the largest rotorcraft to fly in the United States.

The project was abandoned shortly thereafter, and a 16-seat civil variant, the KH-2, never left the drawing board.