Circumstances:
The flight was normal in calm conditions until about 30 minutes from the destination. At that point, the pilot encountered what he described as severe turbulence and found maintaining control of the aircraft difficult. The pilot reported that in the circuit area the strong turbulence persisted, with up-drafts and apparent wind shear. The windsock had been blown away the previous night, but the pilot, using forecast winds and observations, assessed the wind as 350/20 and made an approach for a landing into the north. Reduced flap and increased approach speed were used to counteract the effects of the turbulence. On short final the aircraft encountered a change in wind direction, accompanied by strong gusts and shear, causing it to swing viciously to the right. The pilot attempted to continue the approach for landing, maintaining the aircraft's attitude with elevator and correcting for the swing using opposite rudder, without increasing the power. The stall warning began to sound and the right hand wing dropped. The aircraft entered a descending right hand turn, rotated through approximately 180 degrees and impacted the ground with its right hand wing tip and nose, before rolling inverted. Local inhabitants reported that severe wind shear can occur in this area when strong northerly winds mix with the afternoon southerly sea breeze. This accident was not the subject of an on-scene investigation.
