What happened
On March 1, 1980, a flight instructor and a student pilot prepared for a training flight involving spirals in a Piper J3C, registration HB-OSM. After taxiing to the start of runway 01, the crew observed fog settling over the airfield. Due to the deteriorating visibility, the instructor decided to abort the flight and instructed the student to return the aircraft to the hangar.
Upon reaching the hangar area, the instructor brought the aircraft to a stop and set the throttle to idle. The instructor requested that the student keep the engine running while they briefly left the cockpit to consult a colleague regarding the current weather conditions. As the instructor exited the front seat and moved quickly toward the front right of the aircraft to reach the hangar, they walked directly into the rotating propeller, which was spinning at approximately 600 RPM. The impact threw the instructor to the ground. The student remained in the aircraft and sought medical assistance.
The investigation
The investigation established that the instructor was a highly experienced pilot with a professional license and flight instructor rating. The student was an experienced trainee who had been flying since October 1978. At the time of the event, the weather featured clear skies but with fog banks present at the aerodrome, limiting visibility to between 1 and 3 km.
Investigators noted that because the aircraft lacked an electric starter, the engine had to be hand-started, which explained why the instructor left the engine running at idle. The investigation also confirmed that the instructor's movement toward the front of the aircraft was the critical factor in the collision.
Findings
- The instructor sustained multiple injuries, including broken ribs and injuries to the lungs, chest, and ear.
- The primary cause of the accident was the inattention of the instructor.
- The instructor failed to maintain proper clearance from the propeller arc while exiting the aircraft, moving toward the front of the plane rather than around the wing struts to the rear.