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Date Friday 19 May 1978
Time 13:43
Type Silhouette image of generic T154 model; specific model in this crash may look slightly different    
Tupolev Tu-154B
Operator Aeroflot / Azerbaijan
Registration CCCP-85169
MSN 76A169
Year of manufature 1976
Engines Kuznetsov NK-8-2U
Crew Fatalities: 0 / Occupants: 8
Passengers Fatalities: 4 / Occupants: 126
Total occupants Fatalities: 4 / Occupants: 134
Aircraft damage Destroyed, written off
Aircraft fate w/o
Location 5 km SE of Maksatiha, Tver region   Russia
Phase En route
Nature Passenger - Scheduled
Departure Airport Baku-Bina International Airport (BAK/UBBB)
Destination Airport Leningrad-Pulkovo Airport (LED/ULLI)
Narrative Aeroflot Flight 6709, a Tupolev Tu-154B, was destroyed in a forced landing following a loss of power on all three engines.
The aircraft landed in a potato and barley field, bounced and broke up. Two to three minutes after stopping, the aircraft's fuselage caught fire and was destroyed. Four passengers were killed.

The simultaneous shutdown of all three engines occurred as a result of fuel depletion in the collector tank. This depletion happened because fuel was no longer being transferred from the other tanks.
The interruption in fuel transfer to the collector tank could have occurred due to:
- A malfunction in the automatic fuel transfer electrical circuits, possibly caused by a switch failure, activation of a circuit breaker, or a break in the circuit while the automatic mode was engaged.
- The crew manually turning off the "fuel automation" switch and simultaneously setting the "auto-manual" switch to the "manual" position during the transition to manual fuel transfer mode, while turning off the transfer pumps for one group of tanks and subsequently failing to turn on the pumps for the other group of tanks.

In both cases, the flight engineers did not monitor the operation of the fuel system and did not detect fuel depletion (as indicated by the fuel gauge). The warning (red light) indicating a critical fuel level in the collector tank did not activate.

The Tu-154B aircraft's fuel system had significant design flaws - it featured a single collector tank holding 3,300 kg of fuel, which supplied all three engines. There were no alternative fuel lines to supply the engines bypassing the collector tank. A single failure in the fuel system (loss of fuel from the collector tank) could disable all three engines even when fuel remained in the other tanks.

sources

airdisaster.ru
Soviet Transports

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Revision History

Date/time Contributor Updates
02-Jun-2025 09:09 ASN Updated [Narrative]