Another example

The Challenger space orbiter failure in 1997 and the Columbia failure in 2003 each displayed several contributing elements, but the root cause in both cases was human error. Risks were taken without full understanding of the probabilities and without proper balance in senior management deci­sion making — as judged post facto. It is interesting that in none of these cases was the future risk of the event recognized before the fact, even

DC 9 initiated a takeoff run

Sudden loss of power from one engine

Pilot hesitates for 11А seconds before applying ‘abort’ procedure

Pilot steers to left to avoid runway light standards

Aircraft coasts off apron and glides into a ravine

Fuselage breaks in half, killing two passengers

Подпись: Everything appeared normal up to speed V1 After V1, aircraft cannot be stopped safely - takeoff is mandatory Abort procedure: full reverse engine thrust and brakes, warn passengers to brace He knows the aircraft will overshoot the runway The aircraft was below stall speed when it entered the ravine All other passengers and crew escaped

Table 10.1 A typical accident — Toronto Airport

though more junior staff gave clear warnings in all three cases. (The same pattern existed before the recent oil drilling disaster in the Gulf of Mexico.)