Air Accidents Investigation Branch
Whilst the aircraft was in straight and level flight at 184 KIAS, the canopy broke up without warning. The pilot, the only occupant of the aircraft, sustained serious injuries and was unable to continue flying the aircraft. He was wearing a parachute and bailed out, the aircraft entering a descent and colliding with an unoccupied block of flats.
The investigation identified a lack of appropriate bonding between the inner and outer canopy frame around the front of the canopy. This caused localised and increased stresses within the transparency which under flight loads promoted fatigue crack development. When these cracks reached a critical length, catastrophic failure resulted.
One Safety Action has been taken by the aircraft manufacturer and two Safety Recommendations are made regarding the design and installation of the canopy.