NTSB Factual Report

On June 17, 2002, about 1204 Alaska daylight time, an amphibious Grumman Goose G-21 airplane, N21A, sustained substantial damage following a loss of control during the landing roll at the Northway Airport, Northway, Alaska. The airplane was being operated as an instrument flight rules (IFR) cross-country personal flight under Title 14, CFR Part 91, when the accident occurred. The certificated private pilot and the two passengers were not injured. Visual meteorological conditions prevailed, and an IFR flight plan was in effect, but was canceled prior to starting the visual approach for landing. The flight originated at 1101, from the Whitehorse International Airport, Whitehorse, Yukon, Canada.

During a telephone conversation with the National Transportation Safety Board investigator-in-charge on June 17, the pilot reported that while on approach for landing on runway 22, he encountered a strong right crosswind. He said that after touchdown, during the landing roll, a gust of wind lifted the right wing, and the airplane veered to the left. The airplane ultimately departed the left side of the runway, rolled down an embankment, and came to rest in an area that contained trees. The airplane sustained substantial damage to the right wing and right horizontal stabilizer.

The closest official weather observation station is at the Northway Airport. On June 17, at 1207, about 3 minutes after the accident, a special weather observation was reporting in part: Wind, 310 degrees at 8 knots with gusts to 15 knots, variable 280 degrees to 350 degrees; visibility, 10 statute miles; clouds and sky conditions, clear; temperature, 71 degrees F; dew point, 39 degrees F; altimeter, 29.73 inHg.

The pilot reported that there were no preaccident anomalies with the airplane.

NTSB Probable Cause

The pilot's inadequate compensation for wind conditions during the landing roll, which resulted in an inadvertent ground loop/swerve. A factor associated with the accident was a crosswind.