Posted on 02/23/2007 2:20:24 PM PST by Paleo Conservative
With the first flight of The Boeing Co.'s 787 only about six months away, the new General Electric engine that will power the Dreamliner made its first flight Thursday -- on the wing of a 747."The engine performed extremely well, and we look forward to gaining additional valuable information on the engine's capabilities from flight testing," Tom Brisken, general manager of the GEnx program, said in a statement. "Today's flight puts us another step closer to certification later this year on the GEnx-1B engine for the Boeing 787 Dreamliner."
The engine is being tested on what's known as a "flying test bed," in this case a modified 747.
Flying out of Victorville, Calif., the 747 climbed to more than 43,000 feet during the initial three-hour engine test.
Over the next three months, General Electric plans about three flights per week as part of the test program leading to engine certification.
Rolls-Royce is also developing an engine for the 787.
The GE and Rolls engines will be much more fuel-efficient than the jet engines that power today's planes.
"During the first flight, the GEnx-1B engine demonstrated aircraft systems and instrumentation functionality, and established engine performance baseline for flight testing," GE said.
The 787 Dreamliner program has entered a critical phase, with assembly of the first plane to begin at the Everett plant in the second quarter. Rollout of that jet will be in July, with first flight expected in late August or early September.
It is critical that the various 787 systems and components -- especially the engines -- work as advertised. Time is short, and Boeing can't afford any showstoppers. Boeing is supposed to deliver the first Dreamliner to All Nippon Airways of Japan in May 2008. Boeing does not want a repeat of what has befallen Airbus and the A380. That 555-passenger plane is two years late.
The GE 747 flying test bed has been used to test a number of new GE engines, including the GE90, which powers Boeing's 777.
Replacing one of the 747 engines with the 787 engine required modifications that were not previously needed. That's because the Dreamliner will be a much more electric plane than today's passenger planes, and it will not use bleed air. This means air will not be bled off the engines to power various 787 systems. This approach has not been used before on a commercial jetliner.
GE's 747 flying test bed was modified for the 787 engine to manage the electrical load from the engine's two starter-generators and to provide the power necessary for electrical ground and air starts. The modifications were completed last month, and the GEnx-1B engine was installed in the inboard location on the left wing in just one day, according to GE.
The majority of the flight tests will occur in Victorville, with some flights in Yuma, Ariz., to test hot weather performance. High-altitude takeoff evaluations will be done out of Colorado Springs, Colo. A second round of flight testing later this year will focus on the engine control system.
The GEnx began ground testing in March 2006, with engine certification scheduled for September.This same GE engine will be used to power Boeing's 747-8, which is now in development. But that engine will be changed slightly because the 747 needs bleed air.
The GEnx engine will succeed GE's CF6 engine family and will provide better fuel consumption and payload performance. The new engine has both a front fan case and fan blades made of composites, which provide for greater engine durability, weight reduction and lower operating costs.
It's my understanding that the CF series is a joint venture with the French. Do you know if this engine is part of the JV, or if it is all-American?
Actually, it was CFM International that was a joint venture between General Electric (which used the engine core from the F101 engine used on the B-1 bomber) and SNECMA (who developed the large front fan). The result was the world's most popular high-bypass turbofan engine, the CFM56 series; it's used on DC-8's, 737's, A320 Family planes, and the A340-200/300 series. The GE90 engine used on the Boeing 777 also used a lot of SNECMA parts, too.
That's what's so interesting about the 747-800, the next generation 747 - it's going to have four of those GEnx-series engines on it.
The buy in was too high on the 787, and Pratt didn't want to pony up the money.
Pratt is still kicking itself for not partnering with SNECMA on the 737-300 engine so they are waiting for the next gen 737.
Better 30 years late than never.
I have no idea what you are talking about, but it just seems to make sense!
See post 22 above for some background. It was the CFM engines that were made in a joint venture between GE and SNECMA.
When they closed the Stratford plant, all the Lycoming designers went up the road to East Hartford.
Having worked the Overhaul side of Lycoming geared Turbofans, all I will say is scaling it up to 5 times the thrust is a non trivial task and I personally would not stake my company on it's success or failure.
I can imagine getting the MTBF of the transmission up to par with any other modern turbofan engine while still keeping it light enough is no trivial task.
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