Background
The aircraft, a Beech 76 Duchess registered G-BMJT (manufactured 1981), was powered by two Lycoming O-360-A1G6D piston engines. It was being operated on a private flight by a pilot with approximately 3,000 hours total flying experience, of which about 2,400 were on type. Prior to 8 April 2005, the pilot had noticed an increase in oil temperature on the left engine and contacted his maintenance organisation. The organisation recommended replacing a thermostat valve (vernotherm) in the oil system. A replacement valve was dispatched.
Maintenance Activity
On 10 April 2005, an engineer met the pilot to replace the valve. During a ground run of the left engine, the oil temperature was observed to be higher than the right engine but within the green band. The left engine oil pressure fluctuated briefly, cylinder head temperature was higher, and fuel pressure gauges gave erratic readings. After replacing the vernotherm and conducting a second ground run, the oil temperature dropped below 200°, but the fuel pressure remained off-scale. An inspection revealed no leaks. The pilot was aware of unreliable instrument readings but had made efforts to correct them.
Accident Flight
The pilot departed Isle of Man earlier that day with a passenger, landing at Belfast City Airport at 1614 hrs. The passenger left the airport. After paying landing fees, the pilot returned to the aircraft. At 1640 hrs he requested start clearance. At 1645 hrs, after receiving an airways clearance, he taxied to Runway 22. Takeoff clearance was given at 1647 hrs; the tower controller observed the aircraft become airborne and the landing gear retract. Shortly after, the controller heard a change in engine note, described as a sound of an engine running down. The aircraft began a left turn, descending, and struck trees before crashing into a sports field, coming to rest against a steel mesh fence. A fire started immediately.
Aftermath
The pilot escaped unassisted but suffered severe burns. Bystanders assisted him. The Airport Fire Service arrived six minutes later. The pilot was interviewed four months post-accident while still hospitalized; his recollection was vague. He recalled a bright flash after lift-off, temporary blindness, and asymmetric power, then aiming for a field. The aircraft was destroyed.
Meteorological Information
Surface wind at 1620 hrs was 260° at 13 kt, visibility 30 km, few clouds at 2,500 ft, temperature 13°C, dewpoint 5°C, pressure 1025 hPa.
Aircraft Information
The aircraft was a twin-engine Beech 76 Duchess, total useable fuel 380 litres, landing gear retraction time about 10 seconds. Performance category E had no requirement for positive climb after engine loss. Minimum control speed was 65 kt, stall speed at full power with 0° flaps about 70 kt, recommended lift-off speed 71 kt.
The engines had a 2,000-hour recommended overhaul life extended with CAA approval. Both propellers had been overhauled and zero-lifed in March 2001.