One of the pilots of Chinook ZD576 expressed a specific
concern about the helicopter's engine control system hours before
he died when the aircraft crashed on 2 June
1994.
The disclosure was made by flight lieutenant Geoffrey Young, a
military helicopter instructor, in a statement to the RAF Board of
Inquiry, which investigated the accident in June 1995.
His statement was among parts of the inquiry that the Ministry of
Defence decided not to publish but which have been seen by Computer
Weekly.
On the afternoon of the accident, Young met Rick Cook, one of the
pilots of ZD576, who expressed concern about the Chinook's control
units.
The safety-critical software-based units were among the main
components in the helicopter's new Fadec engine control system.
They automatically controlled the fuel to the Chinook's two jet
engines, but they were proving unreliable at the time. Engines had
shut down unexpectedly or had surged without a command from the
pilots.
Young asked Cook, "I hear you are going abroad and how are you
getting on with the MK2s?"
He continued in his statement, "[Cook] replied with words to the
effect that the Mk2 was OK, but there were concerns over the
reliability of the engines. He then qualified that as not being
concern for the engines but for their control units. That was the
last time I remember seeing flight lieutenant Cook."
The crash was blamed on Cook and flight lieutenant Jonathan Tapper
but some experts have said a technical problem with the Fadec was
at least as likely a cause of the accident as human error.
' Accountable to whom? p30