Piper PA-18-150 accident near Mcgrath, Alaska, August 12, 2010

The NTSB's narrative final · quoted from the NTSB record

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.

The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.