The Yak-141 (NATO designation Freestyle) is a vertical take-off and landing multi-role fighter. It's original designation was the Yak-41, however this designation was classified by the Soviet military. The Yak-141 was actually a fictitious name, applied to the aircraft which set a number of world records. By this name this shipborne fighter was known in the West, it was also applied for promotional purposes by Yakovlev Design Bureau.
Development of this aircraft began in 1975. It had to become the first supersonic aircraft with vertical take off and landing capability. In addition it should have had weapons and radar, equal to those of the frontline fighters. It is worth mentioning, that Yakovlev Design Bureau already had a great experience in creating aircraft with vertical take off and landing capability, such as the Yak-36 and Yak-38. The last mentioned has been successfully tested during the Soviet war in Afghanistan. However Soviet government and military officials were not entirely satisfied with the Yak-38, as it's performance was not quite enough, especially operational range and electronic systems. Also the Yak-38 was inferior to the British Harrier. So in 1975 Yakovlev Design Bureau was ordered to develop a more powerful and unprecedented plane with supersonic speed, vertical take-off and landing capability, longer range and a powerful armament, that could take-off from aircraft carriers.
Designers from the Yakovlev bureau found out, that the double engine scheme of the Yak-38 and Harrier was not suitable for the new plane. Instead they created a layout with a single engine, that could turn 95° down with two additional vertical thrust engines, located in the middle of the fuselage, just behind the center of gravity. These would turn on only during vertical take-off, vertical landing and hovering. Engineers had to stretch body of the aircraft for aerodynamic stability. This is why the Yak-141 is larger than it's predecessor, the Yak-38.
Initially a "duck" configuration with a single square-shaped engine was discussed, however soon this idea was declined because of low maneuverability and technical problems, even though such scheme was low observable. After nearly 20 years a plane with such kind of layout and propulsion, the X-32, lost tender in the USA during the JSF program to the F-35.
The first prototypes of the Yak-141 were completed in 1987. Altogether 4 planes were built, two for static tests and two for flight tests. Aircraft made it's first flight and test flights began the same year. Flight tests were successfully conducted in 1990, when aircraft made passed a full test program, including vertical take-off and landing, short take-off, flying at supersonic speed then slowing down to hovering and so on. In 1991 during a single flight the new aircraft set 12 world records in it's class. One of the records was achieving a 12 km vertical take-off. After this flight the new plane received the Yak-141 designation.
In 1991 two prototype aircraft performed their first vertical landing on Baku (later renamed Admiral Gorshkov) Kiev class light aircraft carrier.
The Yak-141 was intended both for naval aviation and air force. Primary user was the Soviet Navy. A futuristic and innovative idea was bound with this airplane. Idea was to create a mobile take-off and landing platform, which had small dimensions and could withstand aircraft's weight and hot jets from the engines. This platform would be mounted on the DT-30 Vityaz articulated all-terrain tracked carrier (which was also under development at that time). The Vityaz could transport the platform to such territories, that could not be reached by usual off-road vehicles and were no opportunities to build an airfield. The Yak-141 could land on this mobile platform, fill the fuel from another DT-30 tanker and continue it's mission. Payload capacity of the DT-30 is 30 t, so such kind of mission was no problem for it. Actual tests of the Yak-141, based on the DT-30 were made, however development of the Vityaz was protracted and soon the Yak-141 program appeared to be on the brink of failure. So this unprecedented idea, which could give advantage to the Soviet Union was not implemented.
The Yak-141 was capable of engaging air, ground and sea targets. It was armed with a single 30-mm cannon. Missile armament included the R-73 Archer, R-77 Adder or R-27 Alamo air-to-air missiles and Kh-31 and Kh-35 air-to-surface missiles. This multi-role fighter also had provision to carry unguided air-to-ground munitions and bombs. Wings of this warplane are folding, as it is usual for a carrier-based plane.
The Yak-141 multi-role fighter did not enter production. The funding for this program ceased in 1991 after a landing accident on the aircraft carrier, when one prototype landed during excessive side wind and was badly damaged. After collapse of the Soviet Union military funding was limited. In 1992 the Yak-141 program was canceled as it happened with many other promising weapon systems. Also by 1995 Russia decommissioned all Kiev class aircraft carriers, this plane was intended for.
In 1992 the Yak-141 was presented at Farnborough international air show and Le Bourget in 1993. Visitors and appraisers gave highest marks to this unique aircraft. Some countries showed interest in acquiring this plane, however no actual orders were made.
It the early 1990s Lockheed Martin entered into partnership with Yakovlev Design Bureau for further development of this aircraft. Results of this partnership is unknown, however Lockheed Martin possibly used experience gained from this project developing their own F-35 multi-role fighter.
It is worth mentioning that in the near future USA will operate a large numbers of F-35B Lightining II stealth multi-role fighters with supersonic speed and vertical take-off and landing capability, but propulsion system of the F-35B is very similar to that of the Yak-141, developed more than 20 years ago.