Tu-104 accident near Ussuriysk

The Tu-104 accident near Ussuriysk was an aviation accident that occurred on 2 November 1961 near Vozdvizhenka airfield in the vicinity of Ussuriysk. A Tu-104B airliner of the Khabarovsk Joint Aviation Detachment of the airline Aeroflot was operating scheduled passenger flight SU-007 on the route Moscow — Khabarovsk — Vladivostok, but during the approach to Vladivostok's Knevichi Airport the aircraft collided with obstacles, as a result of which a crack formed in the left wing and the aircraft went around. Because of a fuel leak, the aircraft landed in a field near Vozdvizhenka air base near Ussuriysk. None of the 21 people on board — 13 passengers and 8 crew members — were killed.

Sequence of events

Tu-104B USSR-42504 was to operate flight 7 from Moscow to Vladivostok with an intermediate stop in Khabarovsk on 2 November 1961. On board were 12 adult passengers and 1 child.

When approaching Knevichi airfield at night, the crew received clearance to descend and approach according to the existing procedure, and the landing conditions: cloud cover 10 points nimbostratus at a height of 500 m, visibility 6-8 km, light rain, calm, pressure 766.3 mm Hg, landing heading 250°. This weather, received from the crew of a Tu-104 aircraft that had landed earlier, was an hour old. In fact, at the moment of landing the weather at Knevichi airport was: cloud cover 10 points nimbostratus at a height of 300 m, moderate rain, visibility 1000 m, calm, pressure 765.3 mm Hg, temperature +2°C, humidity 100 %.

The crew was warned that the glide slope beacon was faulty and that the approach should be made with the aid of the precision approach radar.

Descending for landing after the fourth turn, from a height of 400 m the crew began to look out for the approach lights located along the runway centreline from the outer marker (DPRM) to the inner marker (BPRM). When the aircraft was 4 km from the runway, the crew was told that the aircraft was on course and well on the glide path. However, when approaching the inner marker, the aircraft descended to an unacceptably low height and 100 m before the inner marker caught the wires of a high-voltage line, knocked down the inner marker mast and the top of a nearby 10 m tall tree. At that same moment the aircraft commander, not seeing the runway lights, increased engine power and went around. The crew was not warned from the ground that the aircraft had descended below the prescribed glide path. When approaching the inner marker, the second pilot warned the commander: “We're going a bit low”, but none of the crew members reported to the aircraft commander that the inner marker had not yet been passed, while the flight engineer was reporting the flight height from the RV-2: “50 metres, 30 metres”.

Incident

As a result of striking the tree, the leading edge of the left wing received three holes through the entire thickness of the leading edge, reaching the first spar, 400—500 mm wide. At the locations of the leading-edge holes, the drainage and emergency fuel-dump pipelines were crushed, and the fuel supply pipeline of the left engine, located in the area of tank 11, had a through hole measuring 40×15 mm, through which fuel from the landing group of tanks was ejected outward under pressure. Due to the fuel leak, the left engine failed at a height of 600 m. Without reporting what had happened, the crew continued to climb and at a height of 1600 m restored the engine's operation, but at a height of 3500 m the engine failed again. Only after this did the aircraft commander report the engine failure, remaining silent about the aircraft's collision with obstacles during the approach.