NTSB Factual Report

On September 7, 2007, about 1640 Alaska daylight time, a float-equipped Cessna 185 airplane, N1758R, sustained substantial damage when it collided with the water and beach of Lake Spenard, during an emergency landing after takeoff from the Lake Hood Seaplane Base, Anchorage, Alaska. The airplane was being operated as a visual flight rules (VFR) local area personal flight under Title 14, CFR Part 91, when the accident occurred. The airplane was operated by the pilot. The airline transport certificated pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed, and no flight plan was filed.

During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), on September 8, the pilot reported that during initial climb after takeoff from the southeast waterlane at Lake Hood, he noticed that the engine rpm was decreasing, and the manifold pressure was increasing. The airplane attained about 400 feet agl, but did not continue to climb. He said the airplane began to descend, and he turned toward the east to avoid a building. Emergency engine failure procedures failed to restore power, and the pilot turned sharply and descended toward Lake Spenard, leveling the airplane as it collided with the edge of the lake. During the impact, the floats were crushed upward, and the wings were displaced downward.

A postaccident examination of the airplane and engine was done on September 10. No mechanical malfunction was observed during the examination. On September 13, the engine was placed on an engine test stand at an Anchorage engine overhaul facility. The engine attained full rated rpm on the test stand.

NTSB Probable Cause

A loss of engine power for an undetermined reason.