Narrative:The Dash 7 plane had been in Egypt for 2,5 years, but had been stored there for some time. The aircraft was then re-possessed by DNK Leasing, registered in the Cayman Islands and ferried to Guernsey for extensive maintenance. The aircraft remained out of service at Guernsey airport for approximately one year whilst it underwent an extensive programme to ensure that all maintenance required during the previous two years had been fully implemented. This was found to be necessary because the extent of the work carried out during its period in Egypt was not clearly defined by the supporting documentation.
The initial test flight was flown on 25 November 1998, and was satisfactory except that the aircraft did not achieve the requisite climb performance. It was established that No 3 engine was not producing the rated power. This engine was changed and an abbreviated test flight was planned for the 28 November 1998; it was intended that this flight would only cover those elements related to aircraft performance.
Descending from FL100 , at around 7000 feet the no. 1 engine was shutdown. The other three operating engines were at a low power setting. The autopilot was engaged and the flaps were up. The aircraft was then leveled at 5000 feet. As the autopilot attempted to maintain level flight, the pitch attitude increased and the airspeed reduced at a rate of about 1×5 kt. At about 95 KIAS, with the autopilot still engaged and the elevator and the pitch trim continuing to provide a positive pitch-up demand, the pitch attitude started to decrease. The maximum pitch attitude achieved was 8°. The onset of vibrations occurred at about 97 KIAS. Coincident with this was a slight forward movement of the elevator, prior to this the elevator and pitch trim were consistently moving nose up together. The autopilot was not disconnected until 6 seconds later.
The power was then increased on all three operating engines and the autopilot was disconnected. The elevator was 12° and the pitch trim 16.4°, both positive (pitch up) demands. The airspeed was 89 KIAS. The power continued to increase on the three operating engines and the aircraft began to roll to the left to a maximum of 80° angle of bank and this was opposed by the use of up to 54° right spoiler. The pitch attitude reduced to 54° nose down. Power was than reduced on the operating engines. The maximum rate of rotation about the yaw axis was 60°/sec. The DHC-7 spiraled down, crashed nose-down into a field and burst into a flames. The Dash 7 came down close to the A38 at Bickington near Ashburton.
Loss of control
Official accident investigation report
|investigating agency: ||Air Accidents Investigation Branch (AAIB) - United Kingdom |
|report status: ||Final|
|report number: ||AAIB Bulletin 11/99|
|report released:||1 November 1999|
|duration of investigation: ||11 months|
|download report: ||
DHC Dash 7-102, VP-CDY
(AAIB Bulletin 11/99)
Follow-up / safety actions