Engine failures cause GE overhaul
By Ken Stammen, Post staff reporter
Engineers at GE Aircraft Engines are reviewing the design of a widely used engine it makes following the latest in a string of mechanical failures the engine experienced.
The National Transportation Safety Board recommended on Dec. 12 that the Federal Aviation Administration conduct a design review of the engine, the CF6, after investigating a Sept. 22 incident in Philadelphia in which an engine on a USAirways 767 blew apart during a maintenance check.
The NTSB determined that a disk in the engine's high-pressure turbine failed, splitting the engine in half and sending engine parts flying. It said the airplane might not have been able to maintain safe flight if the incident had occurred in the air.
| GE stock fell $4.19 to $43.75 Tuesday. |
That was down nearly 9 percent from its 2000 year-end closing price.
The FAA has not acted on the NTSB's recommendation but GE Aircraft Engines spokesman Rick Kennedy said GE is already doing its own design review. The design and administration of the CF6 is done at GE Aircraft's Evendale headquarters and the engine is manufactured in Durham, N.C.
The engine is one of the most widely used, powering large planes like Boeing's 747, 767 DC-10 and MD-11 and the Airbus Industrie A330.
Kennedy said the cause of the disk's failure has not been determined and there have been no other incidents where that happened.
''There is nothing to suggest a problem with materials or a problem with the design,'' he said.
FAA spokesman Les Dorr Jr. said the agency is likely to order some kind of inspection program to address the disk problem.
Evendale-based GEAE is already spending between $20 million and $30 million to correct other problems with the CF6 that arose earlier last year:
The bulk of that - about $18.8 million - is being spent to comply with an August FAA order that required earlier-than-usual inspections of the compressor spool on CF6 engines built before 1995.
The compressor spool is a high-stress part that compresses air that drives the engines. The order came after cracks in a spool forced a Brazilian airline to abort takeoff in June. GE developed a new compressor spool that it expects to replace the older spools with within five years.
Another problem emerged last year with nozzles that guide air through the back of the CF6. A Continental Airlines DC-10 had to return to Newark airport in April after its CF6 engine disintegrated. CF6 failures forced Continental jets to abort takeoffs in Newark and Amsterdam in September.
Engineers determined that locks on the nozzles had broken, allowing the normally stationary nozzles to rotate and collide with other parts. The FAA issued an order requiring airlines to install a set of pins developed by GE to prevent the nozzles from rotating.
Kennedy said the pins have been installed on all affected aircraft and GE has developed a new nozzle lock that doesn't crack that it expects the FAA require airlines to install later this year.
In a memo circulated to GE employees, GE said the CF6 has logged more than 200 million flight hours on large commercial aircraft and power more than 4,000 takeoffs everyday and sets ''industry leading'' standards for safety, performance and reliability. Kennedy said the incidents have not harmed CF6 sales.
Publication date: 01-03-01
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