[citation needed] The CV-240/340/440 series was used by the United States Air Force (USAF) for medical evacuation and VIP transport and was designated as C-131 Samaritan.

[citation needed][contradictory] The initial trainer model, designated the T-29, was also based on the Convair CV-240 and was used to instruct USAF navigators for all USAF aircraft and United States Navy (USN) Naval Flight Officers (NFOs) selected to fly land-based aircraft.

In 1974, the USAF T-29s with the 323d Flying Training Wing (323 FTW) at Mather AFB, California began to be replaced by the Boeing 737-derived T-43.

[citation needed] From 1952, the USN and United States Marine Corps (USMC) took delivery of 36 R4Y-1 transport aircraft similar to the commercial CV-340 and USAF C-131D, configured with 44 passenger seats and powered by a pair of 2,500 hp (1,900 kW) Pratt & Whitney R-2800-52W engines.

Eventually the C-131 was ferried to Eglin AFB in Florida and a General Electric SUU-11A/A 7.62 mm Gatling-style Minigun was installed.

[11] On 17 December 1960, a USAF C-131D Samaritan crashed at Munich after one engine lost power on takeoff from Munich-Riem Airport.