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Old 28th October 2009, 14:33   #1 (permalink)
 
Join Date: Jan 2007
Location: Newcastle
Age: 30
Posts: 52
A380 fuel burn

Hello all

I saw an advertisement for the engine alliance GP7200 donk for the A380 in a magazine the other day (flight global I think). This advertisement claimed that the GP7200 has a 1% fuel benefit over the roller and therefore made the claim to be better environmentally and financially over its competitor… I thought this info was kept quite guarded by airbus?? Does this boast have any substance, and if so why would anybody equip their A380’s with the rollers??

Thanks in advance
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Old 28th October 2009, 16:18   #2 (permalink)
 
Join Date: Jan 2009
Location: Sin City
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I guess no one other than Airbus would know the actual fuel burn rates between these 2 engines.

As to why the rollers were chosen, it could be simply that the GP7200 is outperforming its estimates leading to its yet to be proven 1 % efficiency.

Or any one of these reasons:
  • price
  • performance suited for the airliner's specific needs for the a/c
  • engineering commonality with existing engines among the airlines fleets
  • political
  • ease of maintenance
  • environmental ( noise )
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Old 28th October 2009, 17:03   #3 (permalink)
 
Join Date: May 2005
Location: USA
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It's like a Porsche 928. It does not matter what engine it has. It's still like marrying a woman that is already 450lbs overweight.
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Old 29th October 2009, 00:40   #4 (permalink)
 
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Location: Gold Coast
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It's not quite as simple as a fuel burn on a new engine alone - The fuel burn to generate the required thrust increases slightly as the engine ages and they all do this at slightly different rates. So, while one engine may well use a little less fuel when new, its advantage may disappear after a couple of years. There's also the installed weight consideration; a threee-spool engine will always weigh more than a two-spool, but can sometimes burn less so you have to look at payload (you can lose four tonnes or so pretty quickly) versus how much fuel you need to fly long sectors, etc.
There's many other factors, but I hope you get the idea.
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Old 29th October 2009, 06:51   #5 (permalink)
 
Join Date: Jan 2008
Location: US
Posts: 46
Quote:
It's still like marrying a woman that is already 450lbs overweight.
Focal, thanks for a truly good laugh tonight. Not wanting to incite one of those AB/B "things," I still have to let on that to me, the A380 looks like a big something that's very pissed-off. If it had fur, I'd run like hell upon sighting one.

Quote:
Or any one of these reasons:
  • price
  • performance suited for the airliner's specific needs for the a/c
  • engineering commonality with existing engines among the airlines fleets
  • political
  • ease of maintenance
  • environmental ( noise )
Supposedly, they're easier to ship as well as they fit lock, stock and barrel into the cargo hold of any garden variety 74. Or so I've read, somewhere here - prolly in this post by BreezyDC.
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Old 29th October 2009, 07:04   #6 (permalink)
 
Join Date: Jan 2009
Location: Sin City
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Quote:
It's still like marrying a woman that is already 450lbs overweight.
Well, at least she "performs" and keeps her partner happy.

t
Quote:
hey're easier to ship as well as they fit lock, stock and barrel into the cargo hold of any garden variety 74. Or so I've read, somewhere here - prolly in this post by BreezyDC.
Yup. True. That will fall under the ease of maintenance category. The Trent 900 can be shipped into the B744F side cargo door, albeit it's a tight squeeze. The GP 7200 can be shipped in parts, although the bigger parts need a AN 124.
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Old 29th October 2009, 08:41   #7 (permalink)
 
Join Date: Jan 2006
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Reminiscent of the old gent was looking at a Silver Shadow in a Rolls dealer. The punter inquired about the fuel economy. The salesman asked if you have to ask then you can’t afford it.
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Old 29th October 2009, 09:21   #8 (permalink)
 
Join Date: Jul 2000
Location: Smogsville
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Quote:
a threee-spool engine will always weigh more than a two-spool
I believe the T800 on the 777 is the lightest of the three (PW/GE/RR).

Triple spool is however heavier the smaller the engine so the T900 may be similar weight to the GP. The RR on the 744 is the heaviest and has the highest fuel burn new but the burn deteriorates less over time compared to the GE/PW engines, the T700 core mod for the -524G/H also helped considerably.
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Old 29th October 2009, 10:21   #9 (permalink)
 
Join Date: Jan 2007
Location: Newcastle
Age: 30
Posts: 52
thanks for the replies everyone much appreciated..

so although the specific fuel consumption of the Engine alliance may well be 1% better at the start of its life, over the full life cycle it may be a different story
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