Date & Time: Mar 11, 1993 at 2020 LT
Operator:
Registration:
N2656N
Flight Phase:
Flight
Flight Type:
Ambulance
Survivors:
No
Schedule:
Bermuda Dunes - Parker
MSN:
421C-0714
YOM:
1979
Crew on board:
1
Crew fatalities:
1
Pax on board:
2
Pax fatalities:
2
Other fatalities:
0
Total fatalities:
3
Captain / Total flying hours:
3250
Captain / Total hours on type:
500
Aircraft flight hours:
4869
Circumstances:
A Cessna 421 crashed after an inflight breakup. Investigation disclosed that the left outboard portion of the elevator assembly (including the balance weight) separated first, resulting in empennage flutter and subsequent in-flight breakup of the empennage. The left elevator outboard hinge and support structure exhibited evidence of hinge overtravel. The left horizontal stabilizer front spar had failed downward; rivets that attached the left outboard hinge to the rear spar of the left stabilizer had sheared; and the left elevator center hinge had been pulled off the rear spar. About 100 flight hours before the accident, maintenance was performed to repair the left elevator balance weight (which was loose) and to repair a damaged stiffener in the center structure of the horizontal stabilizer. However, when examined after the accident, the balance weight was tight and the repair to the stiffener was intact. All three occupants were killed.
Probable cause:
Failure of the left elevator for undetermined reason(s), which resulted in flutter and failure of the empennage, and subsequent uncontrolled collision with the terrain.
Final Report:
N2656N.pdf106.38 KB