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N328KF
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FI: GE Aviation Fires Up First GEnx

Wed Mar 22, 2006 4:15 am

Brief fair use excerpt:
General Electric (GE) started up the new generation GEnx turbofan for the first time on Sunday at its Peebles test site in Ohio.

The engine maker says the GEnx, which is in development for the Boeing 787, 747-8 and Airbus A350, ran at idle thrust setting at first but “was getting close to max thrust” during subsequent runs on Monday.

[...]

Initial tests are focused on the GEnx variant for the 787, with flight tests on GE’s 747-100 flying testbed targeted for the third quarter of 2006. The engine is scheduled to begin flight tests on the 787 around a year later. The first runs of the GEnx come some five weeks after the initial run of the competing Rolls-Royce Trent 1000 which was started for the first time on 14 February.

[...]
http://www.flightglobal.com/Articles/2006/03/21/Navigation/177/205589/General+Electric+performs+first+run+of+new+GENx+engine.html

EDIT: link URL

[Edited 2006-03-21 20:48:25]
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leelaw
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RE: FI: GE Aviation Fires Up First GEnx

Wed Mar 22, 2006 4:37 am

Lex Ancilla Justitiae
 
Glom
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RE: FI: GE Aviation Fires Up First GEnx

Wed Mar 22, 2006 4:52 am

Anyone have any pictures?
 
NDSchu777
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RE: FI: GE Aviation Fires Up First GEnx

Wed Mar 22, 2006 8:41 am

Here's the link to the official press release from GE:

http://www.geae.com/aboutgeae/presscenter/genx/genx_20060321.html

Definitely a big milestone for GE, as well as for the development of the 787, 747-8, and A350.
 
Boeing7E7
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RE: FI: GE Aviation Fires Up First GEnx

Wed Mar 22, 2006 11:05 am

Good God. 80.5K! Perhaps a short field version?

From this design:

With a range of thrust from 53,000 to 75,000 lbs, this GEnx engine will power all versions of the 787 Dreamliner with a common bill of material.
 
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lightsaber
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RE: FI: GE Aviation Fires Up First GEnx

Thu Mar 23, 2006 12:16 am

Quoting Boeing7E7 (Reply 4):
Good God. 80.5K! Perhaps a short field version?

During testing one must prove greater thrust on the test stand than what is allowed in service.  Smile

This will be interesting to see how RR and GE do with these new engines.

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"They did not know it was impossible, so they did it!" - Mark Twain
 
pmg1704
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RE: FI: GE Aviation Fires Up First GEnx

Thu Mar 23, 2006 12:33 am

Can anyone explain what a cycle is? Does 1 cycle = 1 hour the engine is on?

From the GE press release: "The engine's maturation program will accumulate more than 15,000 cycles by entry into service and 50,000 cycles total."

Thanks.
 
GEnxPower
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RE: FI: GE Aviation Fires Up First GEnx

Thu Mar 23, 2006 12:46 am

An aircraft engine cycle is one mission. Start-up -> Ground Idle -> Taxi -> Take off -> Climb -> Cruise -> Descent -> Hold -> Land -> Taxi -> Shutdown.

In a test-stand, it's just from low power to high power and back to low power before shutdown.

[Edited 2006-03-22 16:47:04]
 
roseflyer
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RE: FI: GE Aviation Fires Up First GEnx

Thu Mar 23, 2006 1:30 am

Quoting Pmg1704 (Reply 6):
Can anyone explain what a cycle is? Does 1 cycle = 1 hour the engine is on?

As someone pointed out it is a run from start to finish. It isn't necessarily related to a specific time period.

Quoting GEnxPower (Reply 7):
In a test-stand, it's just from low power to high power and back to low power before shutdown.

Kind of. There are complicated algorithms that are run through in testing. I worked in testing before for electrical generators on the 787 (certainly nothing as large as a jet engine, but still the same concept).

The testing process is incredibly elaborate. There is a lot that has to be done. Some of the most important parts of the testing phase are getting all the sensors to work properly and be able to monitor how the engine works. I have seen the test bay of an engine being tested that had instrumentation that said imminent failure was going to happen and less than later there were flames to the ceiling as a catestrophic failure occured. It is a lot of work to get everything ready for a final product because there is a lot of parts that need to work properly and in a predictable way in order to get the reliability that you see of the final products.

I extend my full congratulations to those engineers that worked hard in order to make the first test. There must have been hundreds of gantt charts and peopel monitoring every stage of the process in order to get the engine to this point. It is a lot of work that has been accomplished by some talented engineers. Good things can still be produced by American enginuity.
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darkblue
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RE: FI: GE Aviation Fires Up First GEnx

Thu Mar 23, 2006 1:58 am

Quoting RoseFlyer (Reply 8):
Good things can still be produced by American enginuity.

Yes, but don't forget the work from Sweden (Volvo), Japan (IHI & MHI), Italy (Avio), and Belgium (Tech-Aerospace). These 5 companies combine for about 35% of the GEnx.

After that, there's GE engineers in Mexico (CIAT), Poland (GE-Polska), Russia (GE-ETEC), France (SNECMA), Brazil (CELMA), Turkey (GEMTC), India (GE-EACoe) and many others that I'm sure I'm forgetting.
 
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lightsaber
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RE: FI: GE Aviation Fires Up First GEnx

Thu Mar 23, 2006 3:41 am

Quoting Pmg1704 (Reply 6):
Can anyone explain what a cycle is? Does 1 cycle = 1 hour the engine is on?

GenxPower has explained a lot so I won't repeat as that answer is accurate enough for this discussion board. Yes test engineering is complicated, but so is being a chef unless you are one.  Wink

What I will note is that in older warranties an engine was guaranteed for so many hours. But... the catch is each cycle (idle to full and back) added one hour for purposes of calculating guarantee work and payments. For example, a 8,000 hour warranty might only cover 4,000 cycles and 4,000 hours of cruise. They were written in different ways. Later engine warranties were written more like a car warranty, 8,000 cycles or 12,000 hours (whichever comes first).

Note: I'm speaking in general. Many MX plans are custom to the airline and believe me, engine makers *want* to sell power by the hour. (Highest premium, but very little risk to the engine buyer.)

Back on topic, This is a big accomplishment for the GenX, but much work lies ahead on the test stand. Stators algorithms must be optimized, fuel maps cleaned up, verifications of boroscope inspection plans etc. And there will be a mistake found. For instance, its quite common to beef up the bearings after an engine makes the test stant. OR... perhaps TSFC was missed and a new fan will be added (rumors are the GenX is doing well). But if a new fan makes it more competitive versus the Trent, they'll change it. Its cheapest to change a fan before the bird strike, water ingestion, and blade out testing.

Maybe they'll change the fuel injectors (GE's traditional Gremlin is fuel injector durability on new designs. Its usually fixed before entry into the fleet. The big exception was early GE-90's. IIRC the fourth fix finally gave that engine durable fuel injectors.). Before the Trent 800, RR had trouble with combustor durability. Pratt traditionally misses fuel burn. (And the 4084's damn guide swirlers, a cheap part buried in the engine that "guides" the fuel injector home... Grrr.... A cheap part forcing engine pulls due to poor durability. Grrr...Any fix that impacts emissions is an expensive fix too... Unlike a fuel injector, these aren't line replaceable.)

I'll be interested to follow this engine through testing. I'm just sad there is no Pratt on the 787.  Sad Cest la vie. (I've gone into more Pratt, GE, and RR issues before, feel free to search for them.)

Lightsaber
"They did not know it was impossible, so they did it!" - Mark Twain
 
andz
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RE: FI: GE Aviation Fires Up First GEnx

Thu Mar 23, 2006 3:46 am

There used to be a video clip on GE's website of the GE90 doing water ingestion tests, looked very impressive, does anyone have it?
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