Casualties unknown

Runway Excursion During Rental Checkout Results in Nose-Over After Striking Snow Drift (N4355Z)

Boulder, CO, US

On February 8, 1989, a Piper PA-18-150 (registration N4355Z) operated by Boulder Flying Service was involved in an aviation accident near Boulder, CO. Investigators recorded the probable cause as: FAILURE OF THE DUAL STUDENT TO MAINTAIN DIRECTIONAL CONTROL AND THE FAILURE OF THE PILOT IN COMMAND (CFI), TO PROVIDE ADEQUATE REMEDIAL ACTION IN A TIMELY MANNER, TO CORRECT THE SWERVE. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 2026-06-10Data APIEditorial standards

During a rental checkout, the pilot made a landing on runway 8R. The check pilot released controls during landing roll; the stick moved forward and engine sped up. The airplane swerved left, struck a snow drift, and nosed over.

Incident Overview

An ATP-rated certified flight instructor (CFI) was conducting a rental checkout with a private pilot. During the session, the check pilot instructed the pilot to perform a landing and, if sufficient runway remained, to execute another takeoff. The pilot completed a landing on runway 8R, which is a 4,100-foot-long by 75-foot-wide asphalt runway.

Sequence of Events

The check pilot had been following through on the controls throughout the landing. However, during the landing roll, he released his grip on the controls and waited for the pilot to bring the airplane to a stop. According to the check pilot, as soon as he removed his hands from the controls, the control stick moved forward and he heard the engine speed up. Subsequently, the airplane swerved to the left.

The check pilot took control of the airplane and attempted to correct the swerve, but his efforts were unsuccessful. The airplane then struck a snow drift located on the left side of the runway and nosed over.

Additional Details

No further information regarding the aircraft, occupants, or extent of damage is provided in the source. The runway conditions, time of day, and weather were not specified. The source does not include any analysis or determination of probable cause.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001213X27711. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.