S7 Airlines Flight 778

S7 Airlines Flight 778 was a scheduled domestic passenger flight from Moscow to Irkutsk, Russia. On 9 July 2006, at 06:44 local time (8 July, 22:44 UTC), the Airbus A310 aircraft operating the route overran the runway during its landing in Irkutsk. The aircraft failed to stop and crashed through the airport's concrete perimeter fence, struck rows of private garages and burst into flames, killing 125 people.

With 125 deaths, the crash remains as S7 Airlines' deadliest aviation disaster. The crash was also the second Russian air disaster in two months, after Armavia Flight 967.

The final report of the Interstate Aviation Committee (MAK) investigation concluded that the cause of the crash was attributed to pilot error. While the captain was reducing the thrust reverser of the right engine, he unintentionally moved the left engine's throttle lever forward, causing the left engine to produce significant thrust. His co-pilot failed to monitor the engine parameters and as a result the crew were unable to realize the source of the problem. The crew failed to resolve the issue and the aircraft eventually overran the runway and crashed.

Flight

S7 Airlines Flight 778 was a flight from Moscow's Domodedovo International Airport to Irkutsk, a major Siberian city in Irkutsk Oblast. Irkutsk International Airport is one of the airports that serves the region near Lake Baikal, which is also a major tourist attraction in the country. The flight was one of the most popular flights in Russia. As it was July, the summer holiday was in effect and the flight was packed with tourists who were going to travel to Lake Baikal.

On 9 July 2006, Flight 778 was scheduled to take off from Domodedovo International Airport at 20:15 Moscow Time (UTC 17:15). On board were 195 passengers and 8 crew members; 2 cockpit crew and 6 flight attendants. The flight was commanded by Captain Shibanov and his co-pilot was First Officer Chernykh. The aircraft took off at 20:17 local time and the course to Irkutsk was set. Due to the possibility of foggy condition in Irkutsk, the nearby Bratsk Airport was listed as the alternate airport for Flight 778. The estimated time of arrival in Irkutsk was at 06:44 Irkutsk Time (UTC 22:44).

At 06:16 Irkutsk Time, the crew reached the starting point for their descent to Irkutsk. They contacted the on-duty controller and obtained clearance to descend to 5,700 meters. During the descent, the crew elected to turn on the engines' anti-icing system. The aircraft descended with an average vertical speed of 12 m/s. Flight 778 was eventually handed over to Irkutsk Approach and was cleared to descent to 2,100 meters. As it was descending, the crew decided to turn on the wings' anti-icing for at least 3 minutes. The crew received the automatic terminal information service (ATIS) for the weather in Irkutsk. The report stated that the visibility was 3,500 meters, surface wind at 4 m/s, increase in cloud base height from 170 meters to 190 meters, light torrential rain and cumulonimbus-covered sky. After receiving the ATIS information, they requested the approach clearance to Irkutsk.

The crew finished the final leg of the approach and requested further permission to continue their approach. They eventually established the glidepath and then carried out the landing checklist. The aircraft was then configured for landing. The crew asked permission to land and the controller granted their request. The autopilot and the autothrottle were disengaged. When the aircraft got out of clouds, the pilots realized that it had deviated a bit to the right of the runway. To correct this, they made a small elevator deflection, which momentarily increased the aircraft's vertical speed, causing the "sink rate" warning to briefly sound.

At 06:43 Irkutsk Time, Flight 778 landed at Irkutsk's Runway 30 with an airspeed of 132 knots.

Accident

Immediately after the touch down, Captain Shibanov armed the spoilers and engaged the aircraft's autobrake to low mode. The reverse throttle lever of the right engine was then pulled to the maximum level to slow down the aircraft. The reverse lever of the left engine, however, was left untouched. Captain Shibanov then pushed the right engine reverse thrust to decrease the rate of deceleration. During the landing roll, the take-off warning suddenly alerted the crew on the aircraft's configuration. As the take-off alert appeared during Flight 778's landing roll, the crew shrugged it off, thinking that it was an error on the warning system. First Officer Chernykh then tried multiple times to erase the warning from the aircraft's cockpit monitor (ECAM). He then reported that Flight 778 had successfully landed on the runway. The controller gave landing confirmation to the crew and instructed them to exit the runway to the left along taxiway 6.

After completing the required tasks for landing, the crew expected the aircraft to slow down. However, it did not and instead it began to pick up speed again. The aircraft had taken up a large portion of the runway with only 800 meters remaining of the runway's asphalt. Captain Shibanov noticed this and asked First Officer Chernykh about what was happening on their aircraft. First Officer Chernykh answered that the RPM was increasing. Captain Shibanov then ordered him to deploy the right engine's thrust reverser again. Subsequently, the right engine thrust reverser was put at its maximum level. Simultaneously, Captain Shibanov tried to slow the aircraft down by applying brakes on full-force.

The crew successfully decreased the aircraft's speed, however the aircraft did not stop. They began to run out of runway as they became closer to the end. Due to their significantly high speed, the aircraft flight system disengaged the spoilers and the autobrakes.

During the commotion, one of the airport's fire trucks had noticed the aircraft's abnormal movement, in which it rolled out in high velocity. The chief of the fire truck then decided to follow Flight 778 and notified the observer of the airport's fire brigade about his intention. Using binoculars, the observer also decided to follow the aircraft's movement. The on-duty air traffic controller, who was observing Flight 778 from the airport's control tower, also noticed that the aircraft was not slowing down.

In the cockpit, the flight crew quickly became confused as to the nature and extent of the situation. The aircraft began to swerve to the left. To counter it, the crew stepped on the rudder pedal and the aircraft started to drift to the right. The crew then tried to correct it again by fully pressing the left rudder pedal but the aircraft continued to drift towards the right. The aircraft then went off the runway at a speed of about 180 km/h and travelled across the airport's grassy area. In desperation, Captain Shibanov ordered the engines to be shut down.

Despite their efforts, the aircraft did not stop. The left engine then clipped an antenna of the airport's localizer beacon and also the fences surrounding it. It then travelled across a road before it finally smashed onto the airport's concrete perimeter fence at a speed of 97 knots (180 kph). The impact caused the nose gear to collapse. The engines detached from the pylons and the aircraft's left wing was sheared off. The fuel on the wings then ignited, creating massive burst of flames. The cabin lights immediately went out. The aircraft then struck rows of private garages and finally stopped. The crash immediately killed one woman passenger, while the rest managed to survive with varying degrees of injuries.