Yakovlev Yak-40

Yak-40
Samara Airlines Yak-40
Role Regional jet/ VIP transport
National origin Soviet Union
Manufacturer Yakovlev
First flight October 21, 1966
Introduction September 1968 (Aeroflot)
Primary user Aeroflot
Produced 1967-1981

The Yakovlev Yak-40 (NATO reporting name: Codling) is a small, three-engined airliner that is often called the first regional jet transport aircraft. It was introduced in September 1968 with Aeroflot.

Contents

Development

By the early 1960s, the Soviet state airline Aeroflot's international and internal trunk routes were been flown by jet or turboprop powered airliners but their local services, many of which operated from grass airfields, were operated by obsolete piston engined aircraft such as the Ilyushin Il-12, Il-14 and Lisunov Li-2.[1] Aeroflot wanted to replace these elderly airliners with a turbine-powered aircraft, with the Yakovlev design bureau being assigned to design the new airliner. High speed was not required, but it would have to operate safely and reliably out of poorly equipped airports with short (less than 700 m, (2,300 ft)) unpaved runways in poor weather.[2]

Yakovlev studied both turboprop and jet-powered designs to meet the requirement, including Vertical Take-Off and Landing (VTOL) designs with lift jets in the fuselage or in wing-mounted pods, but eventually they settled on a straight-winged tri-jet carrying 20 to 25 passengers. Engines were to be the new AI-25 turbofan being developed by Ivchenko at Zaporozhye in Ukraine.[3]

Design

The Yak-40 is a low-winged cantilever monoplane with unswept wings, a large T-tail and a retractable tricycle landing gear. The passenger cabin is ahead of the wing, with the short rear fuselage carrying the three turbofan engines, with two engines mounted on short pylons on the side of the fuselage and a third engine buried in the rear fuselage, with air fed from a dorsal air-intake ahead of the fin by a "S-duct", as was an auxiliary power unit which was fitted to allow engine start-up without ground support on primitive airfields.[4][5] The three AI-25 engines were two-shaft engines rated at 14.7 kN (3,300 lbf). The engines had no jetpipes, and initially no thrust reversers.[6][7]

The pressurized fuselage has a diameter of 2.4 metres (94 in). Pilot and co-pilot sit side-by-side in the aircraft's flight deck, while the passenger cabin has a standard layout seating 24 passengers three-abreast, although 32 passengers can be carried by switching to four-abreast seating. Passengers entered and left the aircraft via a set of ventral airstairs in the rear fuselage.[8][7]

The wing is fitted with large trailing-edge slotted flaps, but had no other high-lift devices, relying on the aircraft's low wing loading to give the required short-field take-off and landing performance. The port and starbord wings join at the aircraft centreline, with the main spar running from wingtip to wingtip, with the wings housing integral fuel tanks with a capacity of 3,800 litres (1,000 US gal; 840 imp gal). The aircraft has a large fin, which is swept back at an angle of 50 degrees to move the tailplane rearwards to compensate for the short rear fuselage. The horizontal tailplane itself is unswept. [5][9]

Operational history

The first of five prototypes made its maiden flight on 21 October 1966,[7] with production being launched at the Saratov Aviation Plant in 1967 and Soviet type certification granted in 1968.[5] The type carried out its first passenger service for Aeroflot on 30 September 1968.[9]

By the time production ended in 1981 the factory at Saratov had produced 1,011 aircraft. By 1993 Yak-40s operated by Aeroflot had carried 354 million passengers.[10] As well as being the backbone of Aeroflot's local operations, flying to 276 domestic destinations in 1980, the Yak-40 was also an export success. A total of 130 were exported to Afghanistan, Angola, Bulgaria, Cambodia, Cuba, Czechoslovakia, Equatorial Guinea, Ethiopia, Germany, Hungary, Italy, Laos, Madagascar, Poland, Syria, Vietnam, Yugoslavia and Zambia.[5][10]

Variants

Operators

Civilian Operators

In November 2011 a total of 220 out of 926 Yakovlev Yak-40 aircraft remain in airline service.[11] Major operators include:

 Afghanistan
 Azerbaijan
 Bolivia
 Bulgaria
 Cuba
 Czech Republic
 Czechoslovakia
 Egypt
 West Germany
 Greece
 Honduras
 Hungary
 Kazakhstan
 Kyrgyzstan
 Libya
 Lithuania
 Moldova
 Philippines
 Russia
 Slovakia
 Soviet Union
 Syria
 Tajikistan
 Turkmenistan
 Ukraine
 Uzbekistan
 Venezuela
 Vietnam

Military Operators

 Angola
Angolan Air Force
 Bulgaria
Bulgarian Air Force - former operator
 Cuba
Cuban Air Force
 Czechoslovakia
Czechoslovakian Air Force
 Czech Republic
Czech Air Force - 8 in service
 East Germany
East German Air Force
 Ethiopia
Ethiopian Air Force
 Equatorial Guinea
 Guinea-Bissau
 Hungary
Hungarian Air Force
 Laos
Lao People's Liberation Army Air Force
 Lithuania
Lithuanian Air Force
 Madagascar
 Poland
Polish Air Force - All 4 grounded
 Russia
Russian Air Force
 Serbia
Serbian Air Force
 Slovakia
Slovak Air Force
 Syria
Syrian Air Force
 Soviet Union
Soviet Air Force - former operator
 Vietnam
Vietnam People's Air Force
 Yemen
Yemen Air Force
 Yugoslavia
SFR Yugoslav Air Force
 Zambia
 Zimbabwe
Air Force of Zimbabwe

Notable accidents and incidents

Specifications (Yak-40)

Data from Jane's All The World's Aircraft 1976–77[7]

General characteristics

Performance

See also

Comparable aircraft

Related development

References

Bibliography

  • Gordon, Yefim, Dmitry Komissarov and Sergey Komissarov. OKB Yakovlev: A History of the Design Bureau and its Aircraft. Hinkley, UK: Midland Publishing, 2005. ISBN 1 85780 203 9.
  • Gunston, Bill. The Osprey Encyclopedia of Russian Aircraft 1875–1995. London:Osprey, 1995. ISBN 1 85532 405 9.
  • Gunston, Bill and Yefim Gordon. Yakovlev Aircraft since 1924. London, UK: Putnam Aeronautical Books, 1997. ISBN 1-55750-978-6.
  • Stroud, John. Soviet Transport Aircraft since 1945. London:Putnam, 1968. ISBN 0 370 00126 5.
  • Taylor, John W. R. Jane's All The World's Aircraft 1976–77. London:Jane's Yearbooks, 1976. ISBN 0 354 00538 3.

External links