AAIB investigation to Cessna 152, G-BMXA
Smoke from engine, Bridge of Earn, Perthshire, 3 October 2019.
Summary:
While en route to Edinburgh during a training flight, thick white smoke began to enter the cabin through the heating vents. The instructor followed the aircraft checklist drills and made a successful forced landing near Bridge of Earn. Both occupants were uninjured, and the aircraft suffered no damage but an engine oil leak was found that had led to the smoke entering the cabin.
Download report: