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Date:Wednesday 2 September 1964
Type:Silhouette image of generic IL18 model; specific model in this crash may look slightly different
Ilyushin Il-18V
Operator:Aeroflot, Krasnoyarsk Civil Aviation Directorate
Registration: CCCP-75531
MSN: 183006904
First flight: 1963
Total airframe hrs:1269
Engines: 4 Ivchenko AI-20K
Crew:Fatalities: 9 / Occupants: 9
Passengers:Fatalities: 78 / Occupants: 84
Total:Fatalities: 87 / Occupants: 93
Aircraft damage: Destroyed
Aircraft fate: Written off (damaged beyond repair)
Location:26 km (16.3 mls) NW of Yuzhno-Sakhalinsk Airport (UUS) (   Russia)
Crash site elevation: 550 m (1804 feet) amsl
Phase: Approach (APR)
Nature:Domestic Scheduled Passenger
Departure airport:Khabarovsk-Novy Airport (KHV/UHHH), Russia
Destination airport:Yuzhno-Sakhalinsk Airport (UUS/UHSS), Russia
Flightnumber: 721
Approaching Yuzhno Sakhalinsk in instrument weather conditions, the crew requested a direct approach without completing the standard approach pattern. A premature descent was initiated and the Ilyushin impacted the wooded side of Mount Ufa (793 metres) at an elevation of 550 metres.
Flight SU721 was a scheduled service from Moscow-Sheremetyevo to Yuzhno-Sakhalinsk via Krasnoyarsk and Khabarovsk.

Probable Cause:

PROBABLE CAUSE: 1) Lack of radar availability at Yuzhno-Sakhalinsk; 2) premature descent; 3) insufficient knowledge of the approach conditions; and 4) poor in-flight planning.

Premature descent
Controlled Flight Into Terrain (CFIT) - Mountain

» Aviation Disasters / D. Gero
» Soviet Transports


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This map shows the airport of departure and the intended destination of the flight. The line between the airports does not display the exact flight path.
Distance from Khabarovsk-Novy Airport to Yuzhno-Sakhalinsk Airport as the crow flies is 588 km (367 miles).
Accident location: Global; accuracy within tens or hundreds of kilometers.

This information is not presented as the Flight Safety Foundation or the Aviation Safety Networks opinion as to the cause of the accident. It is preliminary and is based on the facts as they are known at this time.
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Ilyushin Il-18

  • 569 built
  • 22nd loss
  • 13th fatal accident
  • The worst accident (at the time)
  • 9th worst accident (currently)
» safety profile

  • The worst accident (at the time)
  • 23rd worst accident (currently)
» safety profile

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