The Yakovlev Yak-55, a solitary-seated aerobatic aircraft, has been instrumental in securing numerous world aerobatic championships for skilled pilots.
Additionally, the Lithuanian National Defence Volunteer Forces have adopted the Yak 55 as a training aircraft, further highlighting its versatility and effectiveness in honing pilot skills.
In the 1976 World Aerobatic Championship, the Soviet team emerged victorious by securing the top two positions in the individual competition and also winning the team and women’s competitions in their Yakovlev Yak-50s.
However, they were amazed by the performance of foreign aircraft that could execute the required maneuvers in a smaller space than the Yak-50.
To address this issue, a team at the Yakovlev design bureau, led by Sergei Yakovlev and with V. P. Kondratiev and D. K. Drach as chief engineers, embarked on designing a new aerobatic aircraft that was not related to the Yak-50.
The objective was to create an aircraft that could match the tight, low-speed style of Western aircraft.
The Yakovlev Yak-55, a single-engined all-metal cantilever monoplane, emerged as the final design.
Positioned midway up the fuselage, the aircraft’s wing boasts a thick, symmetrical section that aids in inverted flight.
The pilot is situated within an enclosed cockpit, which features a sliding teardrop canopy positioned level with the trailing edge of the wing.
Notably, the seat is positioned below wing level.
The powerplant remains consistent with the Yak-50, utilizing a 360 horsepower (270 kW) Vedeneyev M14P engine in a tractor configuration.
This engine drives a two-bladed V-530TA-D35 propeller.
Additionally, the aircraft is equipped with a fixed undercarriage, featuring titanium sprung main gear and a tailwheel.
The Yak-55, a prototype aircraft, took its inaugural flight in May 1981 and was publicly introduced at the Moscow Tushino air show in August 1982.
Although it did not participate in the 1982 World Aerobatic Championships, it was showcased at the event.
However, the Yak-55 faced rejection from the Soviet team due to the evolving trends in aerobatic flying.
The Yak-50, known for its high-energy aerobatics, had regained popularity, leading to the Yak-55 being disregarded.
Consequently, the Yak-55 underwent a redesign, featuring new wings with a shorter span, reduced area, and a thinner yet symmetrical aerofoil section.
These modifications resulted in an enhanced rate of roll and speed.
Series production of the Yak-55 commenced in 1985 at Arsenyev, and a total of 108 aircraft were delivered by 1991.
In the late 1980s, efforts were initiated to develop an upgraded variant of the Yak-55, known as the Yak-55M, in response to the requirements set forth by DOSAAF.
This organization demanded an aircraft with even higher rates of roll and sought to compete with the latest designs from the Sukhoi design bureau.
The Yak-55M incorporated a smaller wing, which effectively improved its roll rate as desired.
Its maiden flight took place in May 1989, and production began in 1990.
By the end of 1993, a total of 106 Yak-55Ms had been manufactured, with low-rate production continuing. Variants Yak-55 Prototype/initial production aerobatic aircraft. Long-span wings. Yak-55 Revised production version with reduced wingspan and area. Yak-55M Further revised version, with revised wings. Technoavia SP-55M The SP-55M is a development of the Yak-55M by V. P. Kondratiev, one of the designers of the Yak-55 with a redesigned vertical tail, composite-covered control surfaces, a deeper aft fuselage. Yak-56 The Yak-56 was to be a two-seat trainer based on the Yak-55M, but with a low wing and retractable undercarriage. Power was to have come from a 300 hp VOKBM M-16 8-cylinder x-8 engine driving an AV-16 three-bladed propeller.
The prototype was expected to fly in 1992, but delays in producing the engine meant that Yakovlev decided to produce the Yak-54 instead. Specifications Yak-55M Crew One Length 7.29 m (23 ft 11 in) Wingspan 8.10 m (26 ft 7 in) Height 2.80 m (9 ft 2 in) Wing area 12.8 m2 (138 sq ft) Aspect ratio 5.13 Gross weight 855 kg (1,885 lb) for aerobatics Max take-off weight 975 kg (2,150 lb) for ferry flight Powerplant 1 × Vedeneyev M14P 9-cylinder radial engine, 268.5 kW (360.1 hp) Performance Maximum speed 305 km/h (190 mph, 165 kn) Stall speed 100 km/h (62 mph, 54 kn) Never exceed speed 450 km/h (280 mph, 240 kn) Ferry range 705 km (438 mi, 381 nmi) G limits +9, -6 Roll rate 345 degrees per second Rate of climb 15.5 m/s (3,050 ft/min) Sources Yakovlev Aircraft Since 1924 – Bill Gunston & Yefim Gordon. OKB Yakovlev, A History of the Design Bureau and its Aircraft-Yefim Gordon, Dmitriy Komissarov & Sergey Komissarov. Soviet Aircrafts Illustrated-A.S.Yakovlev. The History of Soviet Aircraft from 1918-Vaclav Nemecek. Soviet AF Fighter Colours 1941-45-Erik Pilaeskii. Soviet Combat Aircraft of the Second World War, Vol 1, Single Engined Fighters-Yefim Gordon and Dmitri Khazanov. Early Soviet Jet Fighters, The1940s and early 50s-Yefim Gordon. Soviet Secret Projects, Fighters Since 1945-Tony Buttler & Yefim Gordon. Soviet Secret Projects, Bombers Since 1945-Tony Buttler & Yefim Gordon. Soviet Aircraft of Today-Nico Sgariato. Modern Soviet Fighters-Mike Spick.