The Yakovlev Yak-141 (Russian:Яковлев Як-141, NATO codename:"Freestyle") is a Soviet, supersonic VTOL-fighter aircraft.
Development of the Yak-141 started in the year 1975, at this time it was called Yak-41. It was developed from the Yakovlev Yak-38. The first conventional flight took place on 9th March 1987 and the first hovering flight was made on 29th December 1989. The main role of the aircraft was to be air defense of the fleet. Its flight performance and avionic systems were known to be similar to those of the current fighters of this time.
The afterburning, vectoring main engine of the Yak-141 was mounted on the rear part of the fuselage. In the year 1991 it was renamed to Yak-141.
The Yak-141 can reach speeds of about Mach 1.7 and was to be as agile as the Mikoyan MiG-29. The program was cancelled in August 1991. The technologies developed for the fully traversable engine were used in the United States for development of the F135 engine (engine of the F-35) by Pratt & Whitney.