What happened
After departing from St. Petersburg, the flight instructor encountered radio malfunctions and an alternator failure. Unable to reset the alternator, the instructor turned off the master switch for the remainder of the flight.
Prior to landing, the instructor reactivated the master switch and extended the landing gear. While a visual inspection confirmed the left gear was down, the gear indicator light did not illuminate. During the landing roll, the right main gear settled onto the runway and collapsed. This caused the aircraft to exit the runway.
The investigation
A post-crash examination by an FAA inspector revealed that the left main gear was extended and locked, but the nose wheel had sheared off and the right gear had collapsed into the gear well. Witnesses reported seeing the right main gear in a trailing position prior to touchdown.
Technical findings included:
- The aircraft battery was nearly depleted of electrical energy, with the low voltage warning light illuminated.
- Although thirty degrees of flaps had been selected, the flaps were only extended approximately 10 to 15 degrees.
- The manual landing gear extension pump was found stowed, and there was no evidence it had been used.
Upon supporting the aircraft and starting the engine, investigators found no further electrical problems.