GE Says Specific Engine That Failed Used Different Parts

The FAA issued an Airworthiness Directive for the type of engine on a British Airways 777 that suffered an uncontained failure on takeoff from McCarran International Airport in Las Vegas last week, though GE, the engine's manufacturer, disputes that the particular engine was covered by the AD.

AD 2011-15-06 for  General Electric Company GE90-76B; GE90-77B; GE90-85B; GE90-90B; and GE90-94B Turbofan Engines  required initial and repetitive fluorescent penetrant inspections (FPIs) and eddy current inspections (ECIs) of the high-pressure compressor rotor (HPCR) 8-10 stage spool, part numbers (P/Ns) 1844M90G01 and 1844M90G02, for cracks between the 9-10 stages at each piece-part exposure.

This AD was prompted by cracks discovered on one HPCR 8-10 spool between the 9-10 stages in the weld joint.

The FAA said it was issuing this AD "to prevent failure of the HPCR 8-10 stage spool, uncontained engine failure, and damage to the airplane."

The AD became effective August 18, 2011.

Initial examination of the left engine by the NTSB revealed multiple breaches of the engine case in the area around the high pressure compressor. Examination of the material recovered from runway found several pieces of the high pressure compressor spool (approximately 7-8 inches in length).

Initial examination of the airplane by NTSB revealed that the left engine and pylon, left fuselage structure and inboard left wing airplane were substantially damaged by the fire.

In a statement posted on Twitter, GE said that the GE90-85B "had two different configurations to the compressor spool. The original compressor spool is involved in the BA event; the later compressor spool configuration is referenced in the FAA AD.

"That 2011 AD does not relate at all to the compressor spool in question in the BA event. The FAA AD refers to inspecting a weld that doesn't exist in the original spool configuration, The AD was essentially a modification to the operating manual. It's simply an issue of two different configurations."

(Image from file)

FMI: AD