Yakovlev Yak-52

Yak-52
Yak-52
Role Two seat trainer aircraft
Manufacturer Yakovlev,
Aerostar
First flight 1976
Introduction 1979
Status Operational
Primary users Soviet Air Force
DOSAAF
Developed from Yakovlev Yak-50

The Yakovlev Yak-52 (Як-52) is a Soviet primary trainer aircraft which first flew in 1976. It is still being produced in Romania by Aerostar, which gained manufacturing rights under agreement within the now defunct COMECON socialist trade organisation. The Yak-52 was designed originally as an aerobatic trainer for students in the Soviet DOSAAF training organisation, which trained both civilian sport pilots and military pilots.

Since the early 1990s and the fall of the Soviet Union, many Yak 52s have been exported to the west. Of the approximately 1,800 produced to date, most now fly in the United States, United Kingdom, New Zealand, Australia and other western countries.

Contents

Design and development

A descendant of the single-seat competition aerobatic Yakovlev Yak-50, the all-metal Yak-52 is powered by a 268 kW (360 hp) Vedeneyev M14P 9-cylinder radial engine. The aircraft has inverted fuel and oil systems permitting inverted flight for as long as two minutes. The engine drives a two-bladed counter-clockwise rotating, variable pitch, wood and fiberglass laminate propeller.

At 998 kg (2,200 lb) empty weight, the Yak-52 is responsive and very capable as an aerobatic aircraft. Yet it is also easy to fly and land. It has been used in international aerobatic competition up to the Advanced level. It is stressed to +7 and –5 Gs, rolls (to the right) at 180 degrees/second and is capable of every manoeuvre in the Aresti catalog.

The Yak-52, like most Soviet military aircraft, was designed to operate in rugged environments with minimal maintenance. One of its key features, unusual in western aircraft, is its extensive pneumatic system. Engine starting, landing gear, flaps, and wheel brakes are all pneumatically actuated. Spherical storage bottles for air, replenished by an engine driven compressor, are situated behind the rear cockpit and contents displayed on the instrument panels. The operating pressure is between 10 and 50 bars (145 and 725 psi) and an emergency circuit is reserved for lowering the undercarriage if the normal supply is exhausted or the compressor fails. Additionally both main and reserve bottles can be charged from a port on the ground with compressed air, usually from a Scuba type air bottle. The ground steering/braking arrangement, especially, takes some adjustment for flyers accustomed to hydraulics, because the plane uses differential braking controlled by rudder pedals and a hand operated lever on the control stick.

The tricycle landing gear is retractable, but it remains partially-exposed in the retracted position, affording both a useful level of drag in down manoeuvres and a measure of protection should the plane be forced to land "wheels up."

A number of "westernised" versions of the Yak-52 are now produced. The replacement of the existing Soviet avionics, fitting of a three-blade propeller and the M14PF 298 kW (400 hp) upgrade to the usual 360 hp M14P engine, and conversion to conventional "tail-dragger" landing gear (Yak-52TD) are some of the modifications made to the standard aircraft. There is also a factory produced Yak-52TW tail-dragger version. The TW has an extra 120 l (32 US gal) of fuel capacity in two extra wing tanks, the M14PF engine designated & three blade propeller, an electric start, and modern instruments.

On April 16, 2004, a modernised variant Yak-52M was flown in Russia. It is fitted with modernised M-14Kh engine, three-blade propeller, and other modifications.

Variants

Yak-52
Two-seat primary trainer aircraft, powered by a 360-hp (268-kW) Vedeneyev M-14P 9-cylinder radial piston engine.
Yak-52
Modernised version, powered by a Vedeneyev M-14Kh radial piston engine, fitted with a three-bladed propeller.
Iak-52
Romanian designation of Yak-52.[1]
Aerostar Condor
Westerised version proposed by Aerostar, powered by Lycoming O-540 engine.[1]

Military operators

 Armenia
 Georgia
 Hungary
 Latvia
 Lithuania
 Romania
 Russia
 Soviet Union
 Turkmenistan
 Vietnam

Specifications (Iak 52)

Data from Jane's All The World's Aircraft 1993-94[1]

General characteristics

Performance

See also

Related development

References

  1. ^ a b c Lambert 1993, pp. 248–249.

External links