Odd engine failures with 777s

Three 777s have been diverted since December 07 for engine failures in flight. All three have been powered by GE90-115Bs, which had a record of 11 years without a failure.

In the first incident and Air France 777-300ER developed a vibration in the engine and made an emergency landing in Rome. It was discovered that there was excessive wear on a stage 6 turbine blade.

The second incident was when another Air France 777 diverted to Milan Malpensa after a loss of power. The transfer gearbox broke free of its housing causing the power loss.

The third was on the 1st of Feb when a Singapore Airlines 777 landed in Frankfurt after an inflight power down. It's not known if it was shut down, or if it failed in flight. It had an undisclosed problem with the accessory gearbox in the engine.

An unusual rash of engine shutdowns since early December has temporarily stranded three of the normally reliable General Electric-powered Boeing 777-300ERs.

Although each incident involved a shutdown of the GE90-115B, GE’s investigation so far indicates the causes of each power loss appears to come from three different sources, says a company spokeswoman.

The incidents have forced two different Air France airliners to make emergency landings at alternate airports since 12 December. Similarly, on 1 February, a Singapore Airlines 777-300ER was forced to land at Frankfurt International Airport in Germany.

Source

The last one is of most interest - and `unknown` power down - the BA crash was also as a result of a power down, but its engines are RR Trent 800`s.

I guess a connection exists between chemtrails and jet-engine failures. If the failure rate will increase then the connection is justiffied..

reply to post by sty
Uhhmm... care to explain what you mean by this ambiguous statement? Cant quite see how the fabled chemtrails are linked to unexplained shutdowns of GE-90's or any other 777 powerplant for that matter.

LEE.

reply to post by Harlequin
I tend to agree Harlequin. The first two incidents were old fashioned physical mechanical problems. The last is puzzling as there appears to be no link between a GE-90 problem and any issues with the Trent-800, other than the common core aircraft systems. One thing I have noted over the last few years though is that there have been a number of notable 777 engine incidents. Everything from thrown blades puncturing the fuselage to the BA crash. Could it be that the GE-90/RR Trent-800 are pushing the current limits of manufacturing technology for an engine of this size? Or is it just an over focusing media and some bad luck?

LEE.



[edit on 6-2-2008 by thebozeian]

thrown blades huh?

I do know that in the last 10 years there has been a revolution in the way tubine blades are made.
In some cases blades that were forgings are now milled out of bar stock.
Also the roots used to be broached, a very slow operation, but it is a cold cutting operation. The roots are ground in some cases, and grinding causes heat.

Originally posted by punkinworks
thrown blades huh?

I do know that in the last 10 years there has been a revolution in the way tubine blades are made.

probably going off topic here but aren't some jet engine blades made of carbon fibre? I'm sure i saw it mentioned somewhere that Roll's Royce were using carbon to make the blades for some of their engines?

reply to post by punkinworks
Yeah punkin there was one I know of in Melbourne in early 2001. Threw a blade quite nicely, cant remember if it was Cathay or Singapore owned.

LEE.

The interesting thing about these is that the same company has manufactured both gear boxes that failed. I wonder if it's a QA issue, or if they're cutting corners trying to get costs down.

reply to post by Zaphod58

Would it be the first time a company took risks to cut corners and get stuff made cheaper at same retail price to turn up a bigger profit?

This is one industry however, I hope no one ever cuts corners in because that's hundreds of lives in the balance in each incident.

Shattered OUT...

reply to post by ShatteredSkies


F15 longerons - `nuff said really about corner cutting (

Don't make me cry.

Shattered OUT...