Casualties unknown

1991-08-08: Bell 412 (N177EH) — Era Aviation Inc. — Rowan Midland

Rowan Midland, US

On August 8, 1991, a Bell 412 (registration N177EH) operated by Era Aviation Inc. was involved in an aviation accident near Rowan Midland. Investigators recorded the probable cause as: The tail rotor drive shaft had been assembled incorrectly and the quill assembly had failed. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive; 2 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 takeoff from a moving vessel, the pilot lost directional control. After attempting to reach an offshore platform, directional instability worsened, prompting a water landing. All 15 occupants were recovered safely. Examination found incorrect assembly of the tail rotor drive shaft and failure of the quill assembly.

Incident Overview

An aircraft experienced a loss of directional control during takeoff from a moving vessel. The pilot elected to continue flight in an effort to reach an offshore platform. As directional control became increasingly unstable, the captain ordered the first officer to perform a water landing. The aircraft's floats were inflated, and the landing was completed without incident. All 15 individuals on board were recovered without injury.

Examination Findings

A subsequent examination of the aircraft revealed two mechanical issues. The tail rotor drive shaft had been assembled incorrectly, and the quill assembly had failed. These findings are consistent with the reported loss of directional control during the takeoff and subsequent flight.

Sequence of Events

The flight began with a takeoff from a moving vessel. Shortly after becoming airborne, the pilot noted a loss of directional control. Despite this challenge, the pilot decided to continue flying toward an offshore platform, presumably to attempt a landing there. However, the directional control problem worsened, leading to the captain's decision to abort the platform attempt and instead land on the water. The aircraft was equipped with floats, which were deployed prior to touchdown. The landing was successful, with no further complications. All 15 occupants were subsequently rescued without incident.

Conclusion

The incident was resolved safely due to the crew's decision to conduct a controlled water landing. The mechanical deficiencies identified—improper assembly of the tail rotor drive shaft and failure of the quill assembly—were the likely cause of the directional control loss. No other contributing factors were reported.

Probable cause

The tail rotor drive shaft had been assembled incorrectly and the quill assembly had failed.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001212X17863. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.