David Learmount/LONDON

Having caused a record 640 fatalities in airline accidents during 1997, controlled flight into terrain (CFIT) has been confirmed as the accident category which poses the greatest danger to life. The latest figures reveal that, despite new technology and a well-orchestrated international campaign to reduce the mistakes which cause CFIT, major airlines remain vulnerable, the Flight International review of 1997 world airline safety reveals.

A 6 August Korean Air Boeing 747-300 crash at Guam and a 26 September Garuda Indonesian Airbus A300B4 accident in Sumatra between them accounted for 462 fatalities. An AeroSvit Yakovlev Yak-42 crash near Thessaloniki in Greece killed all 70 on board, and a Tajik Air Tupolev Tu-154 crash at Sharjah, United Arab Emirates, caused 86 deaths. Preliminary information released by investigators indicates that these were CFIT accidents, and one other jet crash may yet be categorised as such.

CFIT happens in cloud or darkness, usually on the descent towards an airport, when the crew makes a navigational error or descend too low, or both, so that the aircraft hits the ground without the crew realising the danger.

Source: Flight International