Accident Summary
At night, a climbing aircraft experienced a generator failure at 19,000 feet. The #2 generator light illuminated, indicating no output and the generator could not be reset. The #1 generator voltage was observed at 14–15 volts. The crew reduced the electrical load, but the batteries discharged within about five minutes, resulting in a total loss of electrical power.
Sequence of Events
Using a flashlight for illumination, the crew diverted to Chester County Airport, which has a 4,600-foot runway. The landing gear was extended using the emergency system. The elevator trim was inoperative, requiring both pilots to apply back pressure on the yoke to counteract a nose-down tendency. The aircraft touched down approximately one-quarter of the way down the runway. The crew attempted to use thrust reversers, but they were inoperative. The aircraft continued off the side and beyond the end of the runway, striking a wooden beam and a snowbank before coming to rest in a ditch.
Investigation Findings
The investigation revealed a shaft failure of the #2 generator (starter/generator) and worn brushes in the #1 generator. The total electrical failure rendered several systems inoperative, including wing flaps, anti-skid brakes, the captain's airspeed indicator and altimeter, nose wheel steering, and cockpit lighting.
Probable Cause
The official findings attribute the accident to multiple factors: Occurrence #1 (airframe/component/system failure/malfunction) due to inadequate maintenance, a worn generator, generator failure, battery exhaustion, and inoperative electrical, communication/navigation, stabilator trim, flap, steering, anti-skid, and thrust reverser systems. Occurrence #2 (loss of control on ground) resulted from dark night conditions and failure to maintain directional control. Occurrence #3 (overrun) was due to improper use of powerplant controls. Occurrences #4 and #5 involved collision with an object and encounter with terrain.