Casualties unknown

2005-07-08: Cessna 206E (N9428G) — Aeronautical Services — Stuart Island, WA

Stuart Island, WA, US

On July 8, 2005, a Cessna 206E (registration N9428G) operated by Aeronautical Services was involved in an aviation accident near Stuart Island, WA. Investigators recorded the probable cause as: The pilot's excessive airspeed on final for the current runway surface conditions, and the intentional obstruction avoidance maneuver he executed when it became clear the aircraft was about to go off the end of the runway. 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 1781061362Data APIEditorial standards

A pilot landing on a 2000-foot runway at Stuart Island encountered standing water, leading to hydroplaning. The aircraft went off the runway into soft mud, tipping onto its side.

Incident Overview

According to the official investigation, the pilot was operating under marginal VFR conditions and entered the traffic pattern using a close-in dogleg approach to final for a landing to the west. During the approach, the pilot heard another aircraft broadcasting a departure from Stuart Island to the east. The pilot responded with a transmission stating, "Aircraft close in, landing to the west, Stuart." He then prepared to execute a go-around. However, after rounding the corner of the island and rolling out on final, he observed an aircraft pulling off the runway to a grassy area to the south. Consequently, he decided to continue the approach for a full-stop landing.

Landing and Hydroplaning

Upon touchdown on the 2,000-foot runway, the aircraft encountered a significant amount of standing water. The pilot immediately retracted the flaps to increase weight on the wheels for braking. Due to the standing water, the aircraft began to hydroplane. As it neared the end of the runway, it had not yet come to a stop. To prevent the aircraft from going off the far end, the pilot intentionally executed a sharp turn to the right.

Accident Sequence

Just after initiating the turn, the left main landing gear and the nose gear dug into the soft, muddy surface beside the runway. This caused the aircraft to tip up on its left side, and the left wing contacted the runway surface.

Investigation Findings

The investigation determined that a heavy rain shower had passed through the area approximately 15 minutes prior to the landing, leaving a significant portion of the runway surface covered with standing water. In a post-accident interview, the pilot stated that he did not realize how much standing water was on the runway until after touchdown, when water began spraying onto the bottom of the wing and the windshield. He further indicated that if he had known the potential for hydroplaning was so great, he would have reduced his approach speed to compensate for the wet conditions.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20050901X01355. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.