Casualties unknown

1991-06-17: Sikorsky S76A (N5418N) — Petroleum Helicopters — Ship Shoal 290K

Ship Shoal 290K, US

On June 17, 1991, a Sikorsky S76A (registration N5418N) operated by Petroleum Helicopters was involved in an aviation accident near Ship Shoal 290K. Investigators recorded the probable cause as: THE COPILOT'S REDUCTION OF POWER TO GROUND IDLE ON BOTH ENGINES. FACTORS WERE THE PILOT'S POOR LANDING TECHNIQUE AND HIS FAILURE TO ESTABLISH ADEQUATE CREW COORDINATION. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive; 7 related events involving the same aircraft type or operator are linked below.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 1781061362Data APIEditorial standards

During a landing at an offshore oil rig, the pilot allowed the helicopter to drift, placing the right main gear on the safety apron. After two unsuccessful repositioning attempts, a takeoff from hover led to a right turn and subsequent uncontrolled descent.

Incident Overview

A helicopter accident occurred during a landing at an offshore oil rig. The pilot in command allowed the helicopter to drift, resulting in the right main gear coming to rest on the safety apron rather than the designated landing area.

Sequence of Events

The pilot in command attempted two repositioning maneuvers to correct the helicopter's position, but these were unsuccessful. He then decided to take off and land again. During the takeoff from a hover, the pilot applied increased collective pitch. The helicopter responded by turning right around its vertical axis.

The co-pilot interpreted this right turn as a loss of directional control. Without coordinating with or announcing to the pilot in command, the co-pilot reduced both engine speed levers to ground idle, effectively bringing both engines off line.

The main rotor blades subsequently struck the platform structure. The helicopter then descended uncontrolled into the water.

Findings

No mechanical malfunctions were discovered during the post-accident examination. The actions taken by the co-pilot were performed without prior coordination or announcement to the pilot in command.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001212X17268. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.