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Safety Recommendation Details

Safety Recommendation A-10-136
Details
Synopsis: On January 4, 2009, about 1409 central standard time, a dual-engine Sikorsky S-76C++ helicopter, N748P, registered to and operated by PHI, Inc., departed controlled flight and crashed into marshy terrain about 7 minutes after takeoff. Both pilots and six passengers on board were fatally injured, and one passenger was seriously injured. The helicopter was substantially damaged. The helicopter departed Lake Palourde Base Heliport in Amelia, Louisiana, en route to the South Timbalier oil platform in the Gulf of Mexico. No flight plan was filed with the Federal Aviation Administration (FAA)1 for the 14 Code of Federal Regulations (CFR) Part 135 air taxi flight, nor was one required.
Recommendation: TO THE FEDERAL AVIATION ADMINISTRATION: Require that Sikorsky redesign the S-76C++ model helicopter fire extinguisher T-handles and/or engine control quadrant to ensure that the T-handles do not inadvertently dislodge out of their detents due to any external force on the canopy or windshields that could cause unintended movement of the engine power control levers.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Action
Mode: Aviation
Location: Morgan City, LA, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: CEN09MA117
Accident Reports:
Report #: None
Accident Date: 1/4/2009
Issue Date: 11/23/2010
Date Closed: 8/13/2013
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Action)
Keyword(s): Aircraft Design, Fire

Safety Recommendation History
From: NTSB
To: FAA
Date: 8/13/2013
Response: We are pleased that, on October 30, 2012, the FAA issued Airworthiness Directive 2012 22-13, “Sikorsky Aircraft Corporation Helicopters,” requiring S-76++ overhead engine control levers to incorporate a damper and a positive detent for the fly position. Accordingly, Safety Recommendation A-10-136 is classified CLOSED—ACCEPTABLE ACTION.

From: FAA
To: NTSB
Date: 7/1/2013
Response: -From Michael P. Huerta, Administrator: The Federal Aviation Administration (FAA) approved the Sikorsky redesign of the Model S-76C++ overhead engine control lever, incorporating a damper and a positive detent for the .fly position. On October 30, 2012, the FAA issued Airworthiness Directive (AD) 2012-22-13, Sikorsky Aircraft Corporation Helicopters (77 FR 68057), to mandate the incorporation ofthis design change on Model S-76C++ helicopters. A copy of this AD can be found at the following Web site: http://www.gpo.gov/fdsys/pkg/FR-20 12-11-15/pdf/2012-27049.pdf I believe the FAA has effectively addressed this safety recommendation and consider our actions complete.

From: NTSB
To: FAA
Date: 9/20/2012
Response: We continue to support the proposed airworthiness directive (AD), which would require S-76++ overhead engine control levers to incorporate a damper and a positive detent for the fly position. Accordingly, pending the issuance of this AD, Safety Recommendation A-10-136 remains classified OPEN—ACCEPTABLE RESPONSE.

From: FAA
To: NTSB
Date: 6/5/2012
Response: -From Michael P. Huerta, Acting Administrator: The Federal Aviation Administration (FAA) approved in April2011 the Sikorsky redesign of the S-76C++ overhead engine control levers that incorporates a damper and a positive detent for the fly position. On March 29, 2012, the FAA published a notice or proposed rulemaking airworthiness directive to mandate this design change on S-76C++ rotorcraft. I will keep the Board informed of the FAA's progress on this safety recommendation and provide an updated response by March 2013.

From: NTSB
To: FAA
Date: 5/22/2012
Response: Notation 8412: The National Transportation Safety Board (NTSB) has reviewed the Federal Aviation Administration's (FAA) notice of proposed rulemaking (NPRM), titled "Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters," which was published at 77 Federal Register 18969 on March 29, 2012. The NPRM proposes to adopt an airworthiness directive (AD)) for certain Sikorsky Aircraft Corporation (Sikorsky) model S-76C helicopters to modify the engine control quadrant assembly with an improved throttle stop and a wider trigger on each engine control lever (ECL). As noted in the NPRM, the proposed AD was prompted by the NTSB's investigation of a January 4, 2009, accident involving a dual-engine Sikorsky S-76C++ helicopter, N748P, which departed controlled flight and crashed into marshy terrain about 7 minutes after takeoff. The NTSB determined that the probable cause of this accident was (1) the sudden loss of power to both engines that resulted from impact with a bird (red-tailed hawk), which fractured the windshield and interfered with engine fuel controls, and (2) the subsequent disorientation of the flight crewmembers, which left them unable to recover from the loss of power. Contributing to the accident were (1) the lack of FAA regulations and guidance, at the time the helicopter was certificated, requiring helicopter windshields to be resistant to bird strikes; (2) the lack of protections that would prevent the T-handles from inadvertently dislodging out of their detents; and (3) the lack of a master warning light and audible system to alert the flight crew of a low-rotor-speed condition. The bird strike to the upper portion of the windshield caused significant forces that transferred into the overhead engine control quadrant assembly, causing both ECLs to move aft from the normal "FLY" position toward the "IDLE" position. As a result of this investigation, on November 23, 2010, the NTSB issued Safety Recommendation A-10-136, which asked the FAA to "require that Sikorsky redesign the S-76C++ model helicopter fire extinguisher T-handles and/or engine control quadrant to ensure that the T-handles do not inadvertently dislodge out of their detents due to any external force on the canopy or windshields that could cause unintended movement of the engine power control levers. On May 18, 2011, Sikorsky issued Alert Service Bulletin No. 76-76-6A, Revision A, which describes procedures to modify the engine control quadrant assembly with an improved throttle stop and a wider trigger assembly. The FAA is proposing this AD to prevent unintended movement of the ECLs, resulting in main rotor speed decay and subsequent loss of control of the helicopter. The NTSB fully supports the proposed AD for the specified Sikorsky models, which, if implemented, would satisfy the intent of Safety Recommendation A-10-136. The NTSB appreciates the opportunity to comment.

From: NTSB
To: FAA
Date: 7/11/2011
Response: The NTSB notes that the FAA is working with Sikorsky on a redesign of the S-76++ overhead engine control levers to incorporate a damper and a positive detent for the fly position. Pending our review of the FAA’s update and the completed redesign, Safety Recommendation A-10-136 is classified OPEN—ACCEPTABLE RESPONSE.

From: FAA
To: NTSB
Date: 1/31/2011
Response: CC# 201100057: - From J. Randolph Babbitt, Administrator: For the past year, the FAA's Boston Aircraft Certification Office and the Rotorcraft Directorate have been working with Sikorsky on a redesign of the S-76C++ overhead engine control levers to incorporate a damper and a positive detent for the fly position. These design changes are expected to be certified in 20 II. An Airworthiness Directive will be issued shortly after the design changes are complete to require replacement of the existing controls with the new design. I will keep the Board informed of the FAA's progress and provide an updated response to this recommendation by December 2011.