History of Flight
On February 4, 2021, at about 1051 Alaska standard time, a Cessna A185E, registration N9725Z, sustained substantial damage when it was involved in an accident approximately 14 miles northeast of Chitina, Alaska. The commercial pilot and passenger were fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 135 scheduled passenger flight.
A Garmin 696 GPSMAP recovered from the accident site provided data logs for the day of the accident. After reaching a GPS altitude of about 7,500 ft, the airplane continued on a southeasterly track for about 10 minutes with a groundspeed between 120 and 130 knots. About 2 minutes before the accident, the airplane initiated a gradual right turn to the south and began a descent averaging about 734 ft per minute. The last fully recorded in-flight data point was at 1050:52, showing a GPS altitude of 5,715 ft, groundspeed of 154 kts, and a track of 282°.
Aircraft Information
The accident airplane had been involved in a collision in May 2014 that damaged the right wing, vertical stabilizer, rudder, right horizontal stabilizer, and right elevator. The right wing was replaced with a wing from a Cessna 180H. The differences between the Cessna 180H wing and the Cessna A185E wing are not structurally significant. Repairs were performed to the outboard upper skin and ribs of the replacement right wing, and the vertical stabilizer, rudder, right horizontal stabilizer, and right elevator were repaired.
Meteorological Conditions
Two pilots who responded to the accident site shortly after the accident reported no turbulence or significant winds aloft from the surface to 5,500 ft msl.
Wreckage and Impact Examination
The wreckage was scattered over mountainous, wooded terrain on the north side of the Chitina River Valley. The main wreckage included both landing gear with wheel penetration skis, engine, firewall, main fuselage, instrument panel, and left wing. The right wing, right aileron, right lift strut, and empennage were not found with the main wreckage. The part farthest from the main wreckage (top skin of right wing) was about 710 ft away; the empennage was about 446 ft away; and the inboard portion of the right wing was about 407 ft away. The debris path and separated sections were consistent with an in-flight breakup.
Examination of the main wreckage showed evidence consistent with a high-speed, near-vertical ground impact. The left wing remained attached at the fuselage attach points and exhibited compressive buckling consistent with being intact before impact. The skis and their rigging showed no preimpact anomalies. Flight control continuity was confirmed except where recovery and overload separations existed. Both right-wing attach points showed upward deformation at the wing root, consistent with positive overload separation of the right wing before ground impact. The vertical stabilizer and rudder deformation and fractured attach points indicated the right wing failed first. All examined fracture surfaces had a dull, grainy appearance consistent with overstress separation, with no evidence of corrosion or fatigue.
The two-bladed constant speed propeller remained attached to the crankshaft flange, but the crankshaft was fractured behind the flange. The fractured surface had an angular, dull, grainy appearance consistent with overstress separation. One propeller blade was slightly bent aft and rotated freely; the other was bent aft about 180° with minor leading-edge damage. Engine examination revealed no evidence of any preimpact anomalies that would have precluded normal operation.