Aeroflot Flight 068

Aeroflot

Industry	Aviation
Founded	1923 (1923)
Headquarters	Moscow , Soviet Union
Products	Passenger air transport

Aeroflot Flight 068 was a scheduled passenger service operated by Aeroflot connecting Khabarovsk and Saint Petersburg with stopovers in Novosibirsk and then at Koltsovo Airport in Yekaterinburg. On 16 March 1961, shortly after departing from Koltsovo Airport, the flight’s Tupolev Tu-104B experienced an engine failure, prompting an emergency landing on a frozen lake. The incident resulted in five fatalities among those on board—two crew and three passengers—and two additional deaths occurred on the ground. In total, 46 individuals survived the crash.

Investigation by the Air Accident Investigation Commission determined that the accident was triggered by a fractured turbine blade causing failure of engine number two (right side). However, the crew mistakenly shut down the operational engine, which led to the necessity of an emergency landing outside the airport.

Aircraft

The Tupolev Tu-104B involved in this event was manufactured at the Kazan Aircraft Production Association facility, with its completion date recorded as 24 July 1959. Aeroflot took delivery of this aircraft on 4 August 1959. At the time of the accident, it had accumulated approximately 1,600 flight hours along with 789 cycles of takeoffs and landings.

Accident

File:Gas turbine blade.jpg

An illustration of a turbojet turbine blade. The fractured blade from the accident aircraft broke off at its root, visible at the bottom of this image

Shortly after departing Koltsovo Airport and climbing through an altitude of approximately 140-metre (460 ft), the crew reduced engine power from takeoff settings when engine No. 2 began to experience intense vibrations.

The flight crew was unable to identify which engine was malfunctioning, as the instrument panel was shaking violently, rendering the engine gauges unusable. To isolate the source of the vibration, a crew member attempted to decrease power on engine No. 1 but unintentionally pulled the throttle back too far, resulting in that engine shutting down. With both engines no longer running, the aircraft started descending rapidly, and the pilots concluded there was insufficient altitude to restart engine No. 1.

In search of a safe landing spot, the crew elected to perform an emergency landing on a frozen pond located approximately 9,200 metres (9.2 km; 5.7 mi; 5.0 nmi) from the airport. They executed a 90-degree right turn and descended, aligning for the landing at a high velocity with both flaps and landing gear retracted.

During descent, the airplane’s vertical stabilizer clipped an overhead power line, severing it. The Tupolev first contacted the ice surface with its left wingtip before impacting the frozen pond and sliding about 870 metres (2,854 ft; 951 yd) toward shore. Still traveling at speed, it collided with trees near the shoreline and proceeded to crash into a two-story vacation home’s ground floor, resulting in two fatalities inside.

The majority of the right wing was torn off and lodged inside that residence. Simultaneously, the left wing struck another house, slicing off roughly half of that wing and demolishing the building entirely. Continuing forward, the aircraft hit additional trees before coming to rest approximately 350 metres (1,148 ft; 383 yd) from the pond and 1,220 metres (4,003 ft; 1,334 yd) from where it first made contact with the ice. No fire erupted during or after impact, and the fuselage fractured into three primary sections that remained close together at the crash location.

Investigation

The Air Accident Investigation Commission’s examination of the wreckage revealed that engine No. 2 experienced a contained failure. The primary cause was identified as the fracture of blade number 54 in the turbine’s second stage. This blade developed a fatigue crack along its first locking groove and detached from the turbine hub at high velocity, inflicting severe damage on the engine. The Commission also noted that pilot error in shutting down engine No. 1 contributed as a secondary factor in causing the accident.

Representatives from both the Tupolev design bureau and the engine manufacturer stated that since the failure was contained within engine No. 2, continuing flight on a single engine back to the airport would have been possible. They concluded that mistakenly shutting down engine No. 1 was chiefly responsible for the crash.

See also

• Aeroflot accidents and incidents
• Aeroflot accidents and incidents in the 1960s
• Kegworth air disaster
• TransAsia Airways Flight 235
• Airlink Flight 8911