No fatalities

Sikorsky S-55 Makes Emergency Landing Near Chelan After Hydraulic Failure (N1255T)

Chelan, WA, United States

On July 24, 2009, a SIKORSKY S-55 (registration N1255T) operated by David C. Smith was involved in an aviation accident near Chelan, WA. No fatalities were reported. Investigators recorded the probable cause as: A leak in an internal seal resulted in the loss of hydraulic system pressure. This summary draws on records from NTSB; 4 related events involving the same aircraft type or operator are linked below.

SourcesNTSBPrimary reportUpdated 2026-08-03Data APIEditorial standards

On July 24, 2009, a Sikorsky S-55 (N1255T) conducted an off-airport emergency landing near Chelan, Washington, after losing hydraulic pressure. The pilot, uninjured, landed in a field where the main rotor severed the tail boom upon encountering a hidden hole.

Accident Details

On July 24, 2009, at approximately 1445 Pacific daylight time, a Sikorsky S-55 helicopter, registration N1255T, made an off-airport emergency landing near Chelan, Washington. The pilot, who owned the helicopter, was operating under 14 Code of Federal Regulations Part 91. He held a commercial pilot certificate and was not injured in the accident. The helicopter sustained substantial damage to the fuselage from impact forces.

Sequence of Events

The flight departed Chelan at about 1245 for a local other work flight. Visual meteorological conditions prevailed, and no flight plan was filed. The pilot was drying cherries at low altitude when the helicopter experienced a loss of hydraulic pressure. He climbed the helicopter to clear nearby trees and then executed a run-on landing into a vacant field. During the landing, the helicopter encountered a large hole that the pilot had not seen. The main rotor struck and severed the tail boom.

Post-Accident Examination

The operator reported that a post-accident examination revealed that an internal seal had leaked, resulting in the loss of pressure in the hydraulic system. As of the report date, the National Transportation Safety Board Pilot/Operator Accident Report Form 6120.1/2 had not been submitted.

Probable cause

A leak in an internal seal resulted in the loss of hydraulic system pressure.

Contributing factors

Causes

Malfunction

Other contributing factors

Contributed to outcome