History of the Flight
The pilot planned a private flight from Bournemouth to Manchester with a single passenger. After pre-flight activities, he started engines at approximately 1110 hrs. ATIS reported wind 230° at 10 kt, visibility 10 km or more, few clouds at 1,000 ft, broken at 1,200 and 2,000 ft, temperature 16°C, dew point 12°C, QNH 1015 hPa. The aircraft was cleared to taxi to holding point N for departure from Runway 26 and took off at 1127 hrs.
Accident Sequence
Approximately 55 seconds after becoming airborne, the aerodrome controller asked if the aircraft had a problem, as it was not climbing normally. The pilot responded that he was going around and requested an immediate return. The controller cleared him to land but received no reply. The pilot carried out a forced landing into a field 1.7 nm west of Runway 08 threshold. Neither occupant was hurt.
Pilot's Account
The pilot stated that both engines started normally and propeller checks were satisfactory. He did not bring the aircraft to a halt before applying power. His normal takeoff technique involved setting the propeller levers about half an inch aft of fully forward to prevent exceeding 2,200 rpm. On this flight, the takeoff seemed normal with no drift. After lift-off, he raised the landing gear and noticed a slight left drift. He found the left power lever approximately half an inch behind the right and rebalanced it. Engine indications appeared normal, and no right rudder was needed. Believing climb was insufficient, he increased power and moved propeller levers aft. The aircraft climbed but not well. He began a right turn to return to Runway 26. Engine instruments remained normal with no warnings, but he had to lower the nose to maintain speed above Vmca (88 kt). Realizing the aircraft was no longer climbing, he turned left for Runway 08. The EGPWS generated a sink rate warning. Descending, he decided to land in a field ahead, selecting gear down and power to idle as the aircraft clipped trees at the field boundary. After stopping, he shut down and vacated. He emphasized his technique was no different than usual and could not explain the performance difference.
Accident Site and Damage
The aircraft landed heavily in a large field about two miles west of Bournemouth Airport, having hit young trees on the bank of the River Stour at a height of approximately 10 ft. The nose leg detached and was found 50 m from the trees along with small debris. Ground marks indicated the aircraft briefly became airborne again between 90 and 100 m from the trees before the main landing gear collapsed. The aircraft slid on its belly, rotated left, and stopped 180 m from the trees. Damage included substantial airframe and powerplant damage, collapsed landing gear, broken left main spar, creased rear fuselage, leading edge damage, and detached radome. No fire occurred.
Propeller and Engine Examination
Propeller blade chop marks on the ground indicated approximate rpm of 1,590 (left) and 1,625 (right) at impact, based on EGPWS groundspeed of 88 kt. The pitch changing mechanisms in both hubs failed. The right propeller piston broke off. Fuel leaking from fractured lines was observed when the aircraft was lifted. Fuel samples collected were considered not representative. Filler caps were in good condition, precluding water ingress. The left engine, overhauled in December 2007, had accumulated 15,243 hours and 10,637 cycles. Intake support struts were broken, causing the gas generator to lose location and the impeller to contact the shroud, resulting in burrs and coating abrasion. The right engine was also removed for strip examination. The cause of the apparent power loss was not determined.
Cockpit Switch Positions
After the accident, the landing gear selector was found in the up position. The pilot stated he had not raised it and suggested the passenger might have accidentally knocked it. All other engine controls and switches were in normal shutdown positions.