Quote:
Originally Posted by Karl
Horrific -I understand it was something as simple as a carburetor problem on one engine .
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Part of the final determination in a nutshell, copied and pasted. The fully-detailed final report notes that the left engine had previously (but not always) shut itself down during SOME negative 'g' maneuvers. It is believed that loss of control was induced by asymmetric thrust causing un-commanded yaw during critical phases of maneuvering, first at the apex of the wingover, and secondly, much closer to the ground during the recovery phase with the left engine's sudden increase in thrust as it's fuel flow returned to previous levels. The lengthy full report is available in a PDF file. DD
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Investigating agency: AAIB
Narrative:
The last airworthy de Havilland DH.98 T.Mk. III Mosquito (G-ASKH, ex-RAF serial RR299) crashed on 21-7-1996, 1 mile west of Manchester Barton Airport (EGCB) during an air display. Both occupants were killed (pilot Kevin Moorhouse and engineer Steve Watson). According to the following extract from the official AAIB report into the accident.
"The aircraft left Hawarden at 11:30 hrs on 21 July and flew to Barton Airfield where, after a short period holding off, the pilot started his display routine at 11:56 hours. The main display axis was along Runway 09/27. The routine consisted of a series of non-aerobatic manoeuvres such as climbs, descents, medium turns,level flight at 220 to 240 knots, along the display axis not below 100 feet agl and 'wing overs'; the latter is a manoeuvre which involves the aircraft reversing its course by climbing and rolling to the left or right.
The weather was fine, the surface wind was generally from the south at 9 knots and the temperature was 26 degrees C;the wind at 2,000 feet was 240 degrees and 10 knots. The display was nearing its conclusion with a fly past along the display axis from east to west followed by a steep climb into a 'wing over' to the right during which control of the aircraft was lost.
The aircraft was then observed to complete a number of uncontrolled manoeuvres before control appeared to have been regained, but at too low a height to prevent impact with the ground".
Damage sustained to airframe: Per the AAIB report "Aircraft destroyed". As a result, the registration G-ASKH was cancelled by the CAA on 16-12-1996 as "destroyed".
The inquest one year after the accident found that a historic problem with this aircraft (engine cutting out during negative g) is what caused the left engine to temporarily but fatally cut out during the wing over.