VFR into IMC · NTSB ANC10FA069

PIPER PA-18-150 — McGrath, AK

2 fatal High-time pilotIMC
DateAugust 12, 2010
LocationMcGrath, AK
AircraftPIPER PA-18-150
Purpose of flightPersonal
ConditionsDay · Instrument Meteorological Cond
Phase / occurrenceEnroute-cruise Loss of control in flight
Pilot age79
Pilot total time19,500 hrs · High time
Time in type7,000 hrs
Fatalities2

Probable cause

The pilot’s continued visual flight into instrument meteorological conditions and the airplane’s subsequent aerodynamic stall, which resulted in an in-flight collision with mountainous terrain.

NTSB findings

  • Personnel issues-Action/decision-Info processing/decision-Decision making/judgment-Pilot - C
  • Environmental issues-Physical environment-Terrain-Mountainous/hilly terrain-Contributed to outcome
  • Environmental issues-Conditions/weather/phenomena-Ceiling/visibility/precip-Below VFR minima-Contributed to outcome
  • Aircraft-Aircraft oper/perf/capability-Performance/control parameters-(general)-Not attained/maintained

What happened

The pilot and passenger were in the first in a flight of two airplanes operating as a personal cross-country flight. As the flight progressed, both airplanes descended due to deteriorating weather conditions as they passed over an area of steep mountainous terrain. The second pilot said that visibility deteriorated to a point that it was difficult to discern topographical features. He then lost sight of the first airplane, so he elected to turn around. No further radio communications were received from the accident airplane. The airplane’s wreckage was subsequently found in an area of mountainous terrain, along the anticipated flight path, at the end of a box canyon. During the on-scene examination of the wreckage, no preaccident mechanical anomalies were discovered. Given the lack of mechanical anomalies, the reported weather conditions, and the statement of the pilot of the second airplane, it is likely that the pilot of the accident airplane flew into instrument meteorological conditions while trying to maneuver the airplane through mountainous terrain. Additionally, given the impact signatures, it’s likely that the pilot was attempting to avoid rising terrain by climbing the airplane, which resulted in an aerodynamic stall.

An editorial "what led to it / how to avoid it" analysis for this accident is generated separately and will appear here.

View the official NTSB docket →