Aeroflot Flight U-505 crashed just after

takeoff Takeoff is the phase of flight in which an aerospace vehicle leaves the ground and becomes airborne. For aircraft traveling vertically, this is known as liftoff. For aircraft that take off horizontally, this usually involves starting with a t ...

Tashkent Tashkent (, uz, Toshkent, Тошкент/, ) (from russian: Ташкент), or Toshkent (; ), also historically known as Chach is the capital and largest city of Uzbekistan. It is the most populous city in Central Asia, with a population of ...

on 13 April 1987. Flight 505 was an early morning flight from Tashkent to

Shahrisabz Shakhrisabz ( uz, Шаҳрисабз ; tg, Шаҳрисабз; fa, شهر سبز, shahr-e sabz: "city of green" / "verdant city"; russian: Шахрисабз) is a district-level city in Qashqadaryo Region in southern Uzbekistan. The Economic Co ...

, both in the

Uzbek Soviet Socialist Republic Uzbekistan (, ) is the common English name for the Uzbek Soviet Socialist Republic (Uzbek SSR; uz, Ўзбекистон Совет Социалистик Республикаси, Oʻzbekiston Sovet Sotsialistik Respublikasi, in Russian: Уз� ...

, now the

Republic of Uzbekistan A republic () is a "state in which power rests with the people or their representatives; specifically a state without a monarchy" and also a "government, or system of government, of such a state." Previously, especially in the 17th and 18th c ...

. The flight took off just one minute and 28 seconds after an

Ilyushin Il-76 The Ilyushin Il-76 (russian: Илью́шин Ил-76; NATO reporting name: Candid) is a multi-purpose, fixed-wing, four-engine turbofan strategic airlifter designed by the Soviet Union's Ilyushin design bureau. It was first planned as a comm ...

, thus encountering its

wake vortex Wake turbulence is a disturbance in the atmosphere that forms behind an aircraft as it passes through the air. It includes variety of elements, the most significant of which are wingtip vortices and jetwash. Jetwash refers to the rapidly moving g ...

. The

Yakovlev Yak-40 The Yakovlev Yak-40 (russian: Яковлев Як-40; NATO reporting name: Codling) is a regional jet designed by Yakovlev. The trijet's maiden flight was in 1966, and it was in production from 1967 to 1981. Introduced in September 1968, the Ya ...

then banked sharply to the right, struck the ground, and caught fire. All 9 people on board died.

Aircraft and crew

The aircraft involved, a Yakovlev Yak-40, was registered to

Aeroflot PJSC AeroflotRussian Airlines (russian: ПАО "Аэрофло́т — Росси́йские авиали́нии", ), commonly known as Aeroflot ( or ; russian: Аэрофлот, , ), is the flag carrier and the largest airline of Russia. The ...

as CCCP-87618. At the time of the accident the aircraft had sustained 17,132 flight hours and 20,927 cycles (one cycle equals one takeoff and landing). The crew consisted of the following: *

Captain Captain is a title, an appellative for the commanding officer of a military unit; the supreme leader of a navy ship, merchant ship, aeroplane, spacecraft, or other vessel; or the commander of a port, fire or police department, election precinct, e ...

T. Yunusbek (Юнусбеков Т.) *

Co-pilot In aviation, the first officer (FO), also called co-pilot, is the pilot who is second-in-command of the aircraft to the captain, who is the legal commander. In the event of incapacitation of the captain, the first officer will assume command o ...

Valery Strunin (Струнин Валерий Александрович) *

Flight engineer A flight engineer (FE), also sometimes called an air engineer, is the member of an aircraft's flight crew who monitors and operates its complex aircraft systems. In the early era of aviation, the position was sometimes referred to as the "air me ...

R. F. Davydov (Давыдов Р. Ф.)

Sequence of events

The plane was scheduled to ferry cargo from Tashkent to Shakhrisabz. On board were 1,200 kilograms of mail and 35 kilograms of personal luggage, along with four passengers seated in the cabin. Takeoff weight was 14.4 tons, within the acceptable range. The crew was in a hurry to depart because the cargo was not loaded until 6:00 local time and they were scheduled to depart Tashkent at 5:55; hence the crew took less than a minute to complete the

preflight checklist In aviation, a preflight checklist is a list of tasks that should be performed by pilots and aircrew prior to takeoff. Its purpose is to improve flight safety by ensuring that no important tasks are forgotten. Failure to correctly conduct a pref ...

instead of the usual five minutes. They proceeded to start taxiing on taxiway three to Runway 8L. At 6:09:40 the Il-76 (CCCP-76482) took off from the runway. Immediately they contacted the control tower and requested clearance for takeoff. After receiving permission to taxi onto the runway, and at 6:10:58 they took off without explicit permission to take off, in violation of procedure. The crew put the engines to full power accelerating at 124.2 knots; but at 6:11:04 when the aircraft was no more than 20 meters off the ground it started to bank sharply to the right and at 6:11:15 it crashed into the ground, killing all nine people aboard.

Cause

Aeroflot_Il-76_CCP76482_at_MAN_(16468016461)

The Yak-40 took off 1 minute and 28 seconds after an

. When investigating the causes of the disaster the commission found that despite the IL-76's position it still would have left

wake turbulence Wake turbulence is a disturbance in the atmosphere that forms behind an aircraft as it passes through the air. It includes variety of elements, the most significant of which are wingtip vortices and jetwash. Jetwash refers to the rapidly moving g ...

. The wind was only 1 mph, leading to the conclusion that the behavior of the aircraft Yak-40 can be explained only by hitting the wake turbulence of a much heavier Il-76 taking off from the same runway in just 1 minute 15 seconds before the Yak-40. Tashkent Airport had a minimum takeoff interval of only one minute, regardless of aircraft type, leading to the relatively small Yak-40 quickly losing control and crashing upon encountering the wake vortex.

References

{{coord missing, Uzbekistan U-505 Aviation accidents and incidents in Uzbekistan Aviation accidents and incidents in 1987 Aviation accidents and incidents in the Soviet Union 1987 in the Soviet Union Accidents and incidents involving the Yakovlev Yak-40 January 1987 events in Asia Aviation accidents and incidents caused by wake turbulence

Aircraft and crew

Sequence of events

Cause

See also

References