Talk:General Electric GE90/Archive 1

Article of GE90 reads like the newer GE9X is a more powerful engine, but it is not
Why the article of GE90 reads like the newer GE9X is a more powerful engine, when it is not? Sounds like a publicity effort by the way it is worded.

The rated thrust is a key characteristic of a jet engine and the articles should clearly state that.

At the moment, the GE90 article reads:

"... It was the most powerful and was the largest jet engine, until being surpassed in January 2020 by its successor, the 110,000 lbf (490 kN) GE9X, which has a 6 in (15 cm) wider fan..."

which is not true because the GE90-115 is still the most powerful engine rated at 115,000 lbf. I am sure its one-time ground test beating this figure should not count as an official rated figure for the thrust of this the engine

Regards, Jlascar 19:53, 10 April 2021 (UTC)

Design and Development
In the second paragraph of this section the article refers to the GE90 as "The fan is an advanced, larger diameter unit made from composite materials and is the first production engine to feature swept rotor blades." Yet, in the section Derivatives, it talks about "The GEnx engine, that has been developed for the Boeing 787 Dreamliner and 747-8, is derived from the smaller (i.e. earlier) core variant of the GE90, but features a fan with swept rotor blades." It seems as though these two statements are contradictory due to the "but" in the GEnx version. Which one was first? — Preceding unsigned comment added by 68.59.34.85 (talk) 23:52, 31 January 2013 (UTC)

Speed
What kind of speed can it generate, that is, at what speeds can it propel an airplane (in this case, the 777)? That kind of information is interesting to have in an article such as this one, since laymans, such as myself, can't really relate to the figure for how much thrust the engine can muster. This needs to be "translated" into something more familiar to the average user &mdash; which makes the article more interesting for the casual reader. Regards, Redux 16:01, 10 March 2006 (UTC)

Transport to Boeing
How is this engine transported to the Boeing production site in Everett ? In parts without the fan in a 747 freighter ? Or completely assembled and simply fixed at the wing of a two-engine 747 ? 217.86.42.111 07:52, 17 June 2006 (UTC)

Transport answer:

The engines undergo final assembly (mating the fan and core assemblies) and testing in GE's facilities in Ohio. They are then trucked overland to Boeing Seattle where the EBU hardware is installed (aircraft interface equipiment). They are then further trucked up to the Everett factory for installation on the aircraft. Further ground runs are conducted on the aircraft before first flight and delivery.

What kind of tolerances?

Guinness Book of Records
The sentence "[...] The latest variant, the GE90-115B, has a fan diameter of 128in and holds the Guinness Book of Records for the highest thrust [...]". In its currrent version the sentence reads as if the engine was capable to hold a copy of the Guinness Book of Records. I advise to correct this. --Wendelin 10:33, 24 October 2006 (UTC)


 * I agree and have reworded accordingly --JCG33 21:41, 30 December 2006 (UTC)

B747 ETOPS?
Is it possible to re-engine a B747 to 2 x GE90115B configuration? This would save a lot of fuel due to less drag and less labour for engine maintenance, with more thrust. You would probably need to add one truss per wing, which would couple the original inward and outward engine pylons so they can share the load and stress bearing and fix the new engine to that. Would the new engine fit ground clearance? Is this being done to the A380 adversary B747 Next? 193.226.227.153 20:20, 24 February 2007 (UTC)

The ground clearance would be pretty tight, and the engines might strike in a crosswind. The reengining would also compete with the 777-300, so Boeing would not want that, much like they discouraged reengining 707s, because it would threaten the 757. As far as drag goes, the engines are always sucking in air, so there would not be a significant reduction. Fuel economy would best be improved by swapping the engines for a set of Trent 560's, which burn less than a pair of GE90's, according to this site's A340 page. Plus, ETOPS is a nuisance if something does happen. Mgw89 (talk) 04:29, 28 November 2007 (UTC)

the cost of doing this would be prohibitive if you mean retro-fitting. Furthermore, 747 is QUADjet, most crew would prefer keeping it that way. Make something even more ridiculous.. remove the wing mounted engines on an MD-11 and mount a GE90 in the tail section!! single engine rated airliner... LOL!! —Preceding unsigned comment added by Noserider (talk • contribs) 14:14, 21 May 2008 (UTC)

A380?
This engine with its high thrust would seem to be a match made in heaven for the "super jumbo" looking at the RR trent article it seems it produces far less thrust, and has been chosen by most of the early customers of the A380. Thoughs? Golden Dragoon 06:37, 25 February 2007 (UTC)
 * The GP7000 on the A380 is directly derived from the GE90. &mdash;Joseph/N328KF (Talk) 15:44, 25 February 2007 (UTC)


 * yes but the GP7000 is said to be rated at 81,500lbs of thrust compared to the figure in this article saying the GE90 is rated at at 115,300lbs with a peak (in the guinness book of records) of 127,900lbs.

I may be missing something but the higher thrust GE90 would seem to be a more logical choice than the Trent or GP7000. Golden Dragoon 10:00, 1 March 2007 (UTC)

Quite possibly the parametric design for the A380 didn't 'need' the thrust that four GE90 placements would make. The GP7000 is a derivative, after all, and it's cleared for production by Snecma; remember, due to current politics and the basic economics of international transport it's more convenient for Airbus to use European engine manufacturers for its powerplants. When it comes to airliner design, economic factors such as fuel efficiency, manufacturing/shipping cost, and basic petty politics are a lot more important than thrust. --The Centipede 20:30, 8 June 2007 (UTC)

Putting GE90's on an A380 would be overkill and waste fuel. These guys are bragging if they can increase efficiency by 10%, so that would rule out the GE90/A380 combo. The only reason to put more powerful engines on something is for heavier long range variants that need more fuel. If it were efficient to fly a plane around with over-strong engines, Boeing would never sell any A market 777-200's. Mgw89 (talk) 04:36, 28 November 2007 (UTC)

I think the best thing they could do would to put three GE90's on the A380. Two on the wings, and one on the tail. This would reduce the fuel that the aircraft needed, and also reduce it's emmissions. Not to mension since they wouldn't need as much fuel it would be able to cruise for very long distances. Last note, it would also be much quieter since the GE90's are only 20dB at 100ft. iXetsuei (talk) 22:16, 23 January 2008 (UTC)

Fuel consumption?
What is the actual fuel consumption of a GE90 in gallons/hour (or liters/hour) during max-thrust (takeoff), climb, and cruise?
 * This is not a reliable source but reports "Specific Fuel Consumption: .25 lb/lbt/hr" and "Fuel Burn at takeoff: 3,750 gallons/hr." I'm guessing the first part of that answer is related to Thrust specific fuel consumption but don't know how to translate that into gallons/hour.
 * This is also unreliable but reports an SFC of .361 for the GE90. --Marc Kupper&#124;talk 19:08, 19 June 2010 (UTC)


 * Well, that's a tough question to answer because jet engines are measured in thrust specific fuel consumption, not in lbs/hour. In the same way that your car fuel consumption varies based on the time of year and how you drive, jet engine fuel consumption varies on where you are, weather conditions, etc. So the TSFC number given is usually at a certain altitude at a cruise setting. So to calculate the gallons/hour that the aircraft burns at cruise, you would need to know the thrust at cruise (which is lower than the max sea level thrust given in the article). You would then multiply the TSFC by the thrust, giving you lbm/hour. Then you multiply by the density of jet fuel (in gallons/lbm), which is about 6.8 lb/gal, or 0.15 gal/lb. That will give you gallons per hour.
 * Unfortunately you need thrust at cruise to calculate that. Hope that helps! -SidewinderX (talk) 04:05, 20 June 2010 (UTC)

Specs
What happened there? Mgw89 (talk) 02:34, 24 June 2010 (UTC)
 * An IP editor messed up the specs template. I think I've fixed it now! -SidewinderX (talk) 12:17, 24 June 2010 (UTC)
 * Looks much better. Thanks. I need to figure out all the template stuff. Mgw89 (talk) 22:39, 24 June 2010 (UTC)

Program Cost?
This number cannot be $24 million, it seems that would be closer to the unit cost. Mgw89 (talk) 17:19, 23 January 2011 (UTC)

GE-X resp. GE9X
If 99.500 or 102.000 IBS, in this configuration the X - A/C`s will so or so be underpowered Twins with giantic runway - effords, except it will be manufactured by a very high carbon - value, like 787 or 350.

However, just wantet to say so far: Very good Article. Impressive Engine !

Greetings, Stephan

46.59.177.54 (talk) 20:05, 19 September 2013 (UTC)

On the wing time
Does anyone know the on-the-wing time of these engines (in hours)? Is there such a number? Le Grand Bleu (talk) 18:16, 26 December 2014 (UTC)

Split GE9X as separate article instead of one chapter as GE90
The GE9X was quite different than GE90,even it come from the same root as GE90 But the engine core,fan and combustion chamber is different,we should consider it was a new engine/Successor. --Aaa830 (talk) 06:02, 19 May 2017 (UTC)
 * was? For now it's a GE90 variant, just like the 81-97lbf and the 111-116lbf are variants, with the same kind of differences : 1 more or less HP comp. stage, the fan was already enlarged with different blades before... I propose to wait if its certification sheet is a new one or the same (perhaps its application is already different?)--Marc Lacoste (talk) 09:40, 19 May 2017 (UTC)
 * The problem is that its section is overwhelming the article. Rather than trimming it back, I suggested a split. But we can always trim it back to be like the other variants in the article. - BilCat (talk) 15:14, 19 May 2017 (UTC)
 * Go ahead and split it then if you prefer.--Marc Lacoste (talk) 16:35, 19 May 2017 (UTC)
 * Undue weight is a bit strong, it's not very controversial :)--Marc Lacoste (talk) 16:37, 19 May 2017 (UTC)

"self published"
[moved from User talk:Marc Lacoste, more relevant here]

Why do you call a thesis "self published"? Trigenibinion (talk) 20:01, 30 May 2021 (UTC)


 * You added 2 refs :
 * # jet-engine.net/civtfspec.html clearly states "The technical information presented here is to the best of my [Nathan Meier] knowledge." This is WP:self-published, there is no editorial review, no publisher outside Nathan Meier.
 * # EditionsElodieRouxEngines also clearly states the publisher is "Éditions Élodie Roux" (herself) and it's printed by lulu.com, a self-publishing printer.
 * The initial ref, by contrast, is from Elsevier, one of the most reputable academic publishers.--Marc Lacoste (talk) 05:18, 31 May 2021 (UTC) should be moved to relevant Talk:General Electric GE90
 * I was not taking about those references, but about the thesis approved by 2 professors. Of course I know Elsevier, but there seems to be more than one error on that page (it's common for books to have errata). Trigenibinion (talk) 11:30, 31 May 2021 (UTC)


 * How can I know what you're talking about if you're not precisely referencing it? Use the diffs.--Marc Lacoste (talk) 11:53, 31 May 2021 (UTC)
 * BTW, before using them, I saw jet-engine.net being referenced in an engineering book, and Elodie Roux's handbook quoted in multiple publications. Trigenibinion (talk) 12:36, 31 May 2021 (UTC)


 * Good for them, but they're still self published.--Marc Lacoste (talk) 12:41, 31 May 2021 (UTC)
 * The fact that they agree on this with a peer-reviewed paper increases their credibility. Lots of online references could be considered self-published. Trigenibinion (talk) 16:32, 31 May 2021 (UTC)


 * The peer-reviewed paper may be a WP:reliable source, I didn't check. The fact they republish credible facts is neat but they don't become RS either. Being among lots of self-published sources doesn't help.--Marc Lacoste (talk) 16:36, 31 May 2021 (UTC)