The engine suffered a gradual power loss after take-off until the aircraft could no longer sustain level flight. During the subsequent attempted forced landing the aircraft stalled while the pilot was attempting to avoid obstructions. The only defect found on examination of the engine was a loose connection in the high tension lead from the left magneto to the number 1 cylinder. This, by itself, should not have caused as great a loss of power as was reported by the pilot. The aircraft was overloaded by some 70 kg and this would have contributed to the reduction in aircraft performance.
