EASA SIB 2009-05: Sikorsky S-92A Main Gearbox (MGB) Malfunctions.

What to do

Operators and maintenance organizations should continue to comply with the emergency procedures currently approved in the Rotorcraft Flight Manual. They should monitor communications from Sikorsky and EASA for updates on the investigation and any future approved changes. For further information, stakeholders can contact EASA or Sikorsky Commercial Product Support. No immediate mandatory actions or deadlines are specified in this bulletin.

Summary

EASA Safety Information Bulletin SIB No. 2009-05 addresses malfunctions in the main gearbox (MGB) lubrication system of Sikorsky S-92A helicopters. The bulletin references Sikorsky Safety Advisories SSA-S92-08-006 and CCS-92-AOL-09-0008, highlighting service difficulties and a recent accident involving the S-92A MGB. It informs European operators about the status of Rotorcraft Flight Manual changes and emphasizes adherence to approved emergency procedures.

What changed

EASA SIB 2009-05 clarifies that the Rotorcraft Flight Manual changes proposed in Sikorsky Safety Advisory SSA-S92-08-006 have not been approved by the FAA or EASA and therefore should not be considered mandatory. The bulletin supports the recommendations in Sikorsky Safety Advisory CCS-92-AOL-09-0008, except for the unapproved RFM changes. It serves to update operators on the current regulatory stance pending further investigation.

Why it matters

This bulletin is important for aviation professionals as it ensures that operators of Sikorsky S-92A helicopters in Europe are aware of the regulatory status of safety advisories related to MGB malfunctions. It prevents premature adoption of unapproved flight manual changes, which could affect safety and compliance. Maintenance and operational teams must continue to follow approved emergency procedures to manage risks associated with the MGB lubrication system.

What to do

Summary

What changed

Why it matters

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