What happened
On June 7, 1972, an Aermacchi AL-60, registration HB-ELC, was conducting aerial filming operations near Grindelwald, Switzerland. The mission, organized by a television production company, involved capturing footage of a landscape scene for a film. The flight involved two occupants: the pilot and a cameraman.
After completing several passes over the filming site, the aircraft entered a steep, descending left-hand turn. During this maneuver, the aircraft's speed increased significantly, and it eventually struck trees in a wooded area. The impact caused the left wing to break off and the fuselage to strike multiple tree trunks. The force of the impact was severe enough to eject the pilot and passenger into a nearby marshy clearing. Both occupants sustained serious injuries, and the aircraft was destroyed.
The investigation
Investigators examined the wreckage and analyzed film footage captured from the ground during the accident. The investigation focused on the aircraft's flight path, the mechanical state of the Aermacchi AL-60, and the operational environment.
Analysis of the ground-based film revealed that the aircraft was performing a tight, descending left turn before the impact. The footage showed the pilot attempting a significant positive elevator input to recover the aircraft just before it struck the trees. The investigation also noted that the aircraft's speed had risen to approximately 182 mph, which exceeded the maximum allowable speed of 176 mph.
Findings
- The aircraft was airworthy and properly maintained, with no evidence of pre-existing mechanical failure.
- The pilot held valid licenses and possessed sufficient flight experience.
- The pilot was wearing a portable radio transceiver on his chest, which may have acted as a distraction during flight control.
- The aircraft was flying with flaps retracted during the final maneuver, leading to an increase in turning and recovery radii as speed increased.
- The pilot attempted to pull up the nose of the aircraft shortly before the collision, but the high speed and descent rate prevented a successful recovery.