What happened
On 7 June 1965, a Fokker F-27 Friendship, registration HB-AAU, operated by Balair, was performing a scheduled flight from Geneva to Basel-Mühlhausen. While cruising at 12,000 feet near Bern, the aircraft was struck by lightning on the right side of the nose. Following the strike, the crew noted damage to the right wing tip.
During the approach to Basel-Mühlhausen, the pilot discovered that the nosewheel failed to extend despite the landing gear lever being selected. After an unsuccessful attempt to overshoot and re-extend the gear, and following consultation with Balair management, the flight was diverted to Schiphol Airport. To facilitate an emergency landing, Schiphol authorities prepared a foam path on runway 06. The pilot ultimately performed a nosewheel-up landing at 20:36 GMT. There were no injuries among the 46 passengers and 4 crewmembers.
The investigation
The investigation examined the aircraft's maintenance history, the meteorological conditions, and the physical damage to the airframe. Technical analysis focused on why the nosewheel remained retracted despite the crew's efforts to deploy it. Investigators also reviewed the impact of the lightning strike on the aircraft's structural integrity.
Findings
- The aircraft was properly maintained, and the pilot was appropriately licensed with 800 hours of experience on the type.
- A lightning strike occurred near Bern, causing burn marks on the right wing tip and the lower right side of the nose.
- The lightning strike caused deformation of the fuselage nose, which physically jammed the nosewheel doors.
- This structural deformation made it impossible to extend the nosegear through standard or emergency procedures.
- The landing resulted in damage to the underside of the nose and the nosewheel doors, the latter of which had to be pried open with a crowbar during recovery.