The Learjet Model 35 and Model 36 are a series of American multi-role business jets and military transport aircraft. When used by the United States Air Force they carry the designation C-21A.
The aircraft are powered by two Garrett TFE731-2 turbofan engines. Its cabin can be arranged for 6-8 passengers. The Model 36 has a shortened passenger area in the fuselage, in order to provide more space in the aft fuselage for fuel tanks. It is designed for longer-range mission capability.
The engines are mounted in nacelles on the sides of the aft fuselage. The wings are equipped with single-slotted flaps. The wingtip fuel tanks distinguish the design from other aircraft having similar functions.
In 1976 American professional golfer Arnold Palmer used a Learjet 36 to establish a new round-the-world class record of 22,894 miles (36990 km) completed in 57 hours 25 minutes 42 seconds.
Learjet 35s made the bulk of Escuadrón Fénix during the 1982 Falklands War mainly on diversion flights.
Production on the 35/36 series ceased in 1994.
As of January, 2007, the U.S. National Transportation Safety Board database lists 19 fatal accidents for the 35/35A, and two for the 36/36A.