Casualties unknown

Glider Accident on Landing at Turf Airstrip (N159AS)

Enumclaw, WA, US

On April 27, 2003, a Pilatus B4-PC11AF (registration N159AS) was involved in an aviation accident near Enumclaw, WA. Investigators recorded the probable cause as: The pilot's failure to maintain directional control. Contributing factors were the crosswind/tailwind conditions and the trees which the glider impacted. 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

A glider pilot encountered turbulence while landing at a turf airstrip, resulting in a directional control issue and collision with trees after touchdown.

Accident Sequence

The glider pilot initiated departure under tow from runway 28 at a turf and dirt airstrip. The reported surface winds were calm to 5 knots from the west. After encountering turbulence during the flight, the pilot re-entered the traffic pattern and established an approach for landing on runway 10.

While on final approach, the pilot conducted a 5-degree right-angled approach. Just before touchdown, the pilot attempted to correct this angle by applying left rudder and aileron inputs. However, the glider did not respond to the control inputs. The aircraft touched down with its nose oriented approximately 10 to 15 degrees to the right of the runway centerline. Following touchdown, the glider rolled off the south side of the runway and subsequently impacted trees.

Weather Conditions

The pilot reported that surface winds at the airstrip were calm to 5 knots from the west. However, aviation surface weather observations from multiple sites located north and west of the airstrip indicated generally northwesterly winds ranging from 8 to 11 knots at the surface.

Pilot Report

The pilot stated that there was no mechanical malfunction with the glider at the time of the event.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20030430X00598. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.