NTSB Factual Report

On May 12, 2002, about 1400 Alaska daylight time, a Cessna 170B airplane, N7608B, sustained substantial damage during an aborted takeoff at the Lake Hood Strip, Anchorage, Alaska. The airplane was being operated as a visual flight rules (VFR) personal flight under Title 14, CFR Part 91, when the accident occurred. The private pilot and the three passengers were not injured. The flight was intended to be a local flight, and no flight plan was filed.

During an on-site interview with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on May 12, the pilot said as he started the takeoff roll, the airplane drifted toward the left edge of the runway. He said he was unable to stop it from drifting left, and aborted the takeoff. He said as the airplane decelerated it ran off of the left side of the runway. The airplane skidded sideways, and the left main wheel assembly collapsed inward, and the outboard portion of the left wing struck the ground. The airplane then nosed down and came to rest with the nose touching the ground.

The pilot said this was his second flight in the airplane since its annual inspection was accomplished a week earlier. He said the ground handling characteristics of the airplane had changed since part of the tail wheel assembly was changed during the annual inspection. He said his first flight in the airplane, after the inspection, was uneventful, and no problems with any of the flight controls were noted.

An examination of the airplane at the accident site by the IIC did not disclose any mechanical anomalies. The runway surface was level, packed and loose, gravel. The tire tracks from both main wheels were visible, however, the right main wheel track was more pronounced. The tail wheel track was not visible. The tracks drifted toward the left edge of the runway. At a point near the left edge of the runway, and about 90 feet from where the airplane came to rest, both tracks abruptly become deep furrowed marks. The marks traveled off the runway to the left and then made an arc toward the right. The arc decreased in circumference toward the end of the marks. The airplane was sitting on its main gear and tail wheel. A representative from the airport fire department said the airplane was resting on its left main landing gear, left wing, and nose when they arrived. The fire department lowered the airplane onto its tail wheel to stop the flow of fuel that was leaking from the main fuel tanks. The left main landing gear leg was bent inward and the tire was flat. Both main tires showed signs of lateral scuffing. About five feet of the left wing sustained damage to the leading edge, ribs and skin, and was bent upward about 30 degrees. The left aileron, engine cowling, propeller and spinner, were also damaged. Wind conditions observed at the time of the site investigation were calm to light and variable.

NTSB Probable Cause

The failure of the pilot to maintain directional control during takeoff. A factor associated with the accident was an inadvertent ground loop.