What aircraft was involved and where did it happen?

The accident on 1987-09-27 involved a Hughes 369D, registration N8613F, at Seattle, WA.

Engine Power Loss Leads to Hard Landing and Tail Boom Separation During Autorotation (N8613F)

On September 27, 1987, a Hughes 369D (registration N8613F) was involved in an aviation accident near Seattle, WA. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

A helicopter pilot reported engine power loss at 1,000 feet, initiated autorotation to a park athletic field, but changed touchdown points due to people on the field, resulting in airspeed loss and hard landing that severed the tail boom.

Incident Overview

A pilot reported that while cruising at approximately 1,000 feet, the engine lost power. He initiated an autorotation to an athletic field located within a city park.

Approach and Touchdown

During the autorotation approach, the pilot changed his planned touchdown point several times because of personnel present on the field. According to the pilot, this led to a loss of airspeed. Subsequently, the helicopter landed hard.

Damage

Upon touchdown, the main rotor blades flexed downward and severed the tail boom.

Engine Examination

An examination of the engine found no evidence of a mechanical malfunction that would have resulted in a loss of power.

1987-09-27: Hughes 369D (N8613F) — Seattle, WA