Switzerland’s Aircraft Accident Investigation Bureau has confirmed that human error was to blame for a Crossair plane crash in January 2000, which left ten people dead.This content was published on December 1, 2003 - 12:59
The report into the crash said the flight crew committed a series of errors after their take-off instructions were changed.
The plane was heading for Dresden in Germany when it crashed shortly after taking off from Zurich airport, killing the three crew members and seven passengers on board.
The report identified five causes for the accident, all related to the actions of the flight crew, who lost control of the aircraft, causing it to spiral and nosedive into the ground.
It ruled out technical problems and turbulence as factors contributing to the crash.
In particular, the report found that the flight crew reacted inappropriately to new instructions from the control tower, telling them to turn left after take-off.
The pilot’s decision to switch off the autopilot during the plane’s ascent, a work-intensive phase of the flight, also contributed to the crash.
In addition, the co-pilot programmed an instruction into the cockpit system - without permission from the pilot - but failed to do so correctly. The plane then veered to the right, instead of left as was intended.
As a result, the pilot lost his orientation and the plane plunged into a spiral dive. The co-pilot then failed to do enough to pull the plane out of the dive, said the report.
The report cited a number of other factors that may have also contributed to the accident.
One of them was the Moldovan captain and his Slovakian co-pilot’s failure to fully understand unfamiliar cockpit controls and procedures. The Saab 340 model differed from the eastern European models they were used to.
“When interpreting the… display instruments under stress, the commander resorted to a reaction pattern he had learned earlier,” the report specified.
It also suggested that because the captain only possessed a limited knowledge of English – the lingua franca of international aviation – the two pilots might have had difficulties in understanding each other.
The two crew members were drafted in on short-term contracts because of staff shortages at Crossair.
Previous claims that the captain’s judgement was impaired by his use of the tranquiliser, Phenocepan, were not ruled out.
During its investigation, the Aircraft Accident Investigation Bureau drew up a set of safety recommendations for the Federal Office for Civil Aviation.
These included measures for training new flight crews, compulsory medical checks by a Swiss doctor, and better guidelines on the use of the flight management system.
It also recommended that the autopilot function always be activated at phases of the flight that demand high levels of concentration, such as the initial ascent.
Another measure called for more stringent limits on the use of licensed pilots from countries not in compliance with European standards.
The final report had been delayed after the former Crossair chief, Moritz Suter, managed to block it in March this year, claiming it contained errors. However, the version made public on Monday had not taken Suter's remarks into account.
Crossair went on to form the backbone of the national airline, Swiss, which took to the skies on April 1, 2002.
swissinfo with agencies
The final report into the crash found that the flight crew did not react appropriately to a change in departure instructions.
It said the Moldovan pilot and Slovakian co-pilot’s lack of familiarity with the Western-style cockpit controls may also have contributed to the crash.
The report said the pilot’s use of tranquillisers could have affected his judgement.
In addition, the pilot could not speak good English, the principal language used in international aviation.