Sponsor Message:
Civil Aviation Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
Why Are New Engines Always On Time?  
User currently offlineA380900 From France, joined Dec 2003, 1116 posts, RR: 1
Posted (3 years 9 months 6 days 16 hours ago) and read 12148 times:

Except for the A400M and GTF, it feels like engines are never a problem in terms of development/production schedule. So I'm wondering: are the motorist really pushing themselves and taking risks? Or more or less doing always the same thing with very slow progress?

[Edited 2011-01-22 05:05:58]

39 replies: All unread, showing first 25:
 
User currently offlinequeb From Canada, joined May 2010, 707 posts, RR: 3
Reply 1, posted (3 years 9 months 6 days 16 hours ago) and read 12129 times:

GTF ? No delay announced for the GTF at this time. It's easier to be on time when the aircraft is 3 years late...

User currently offlinemorrisond From Canada, joined Jan 2010, 243 posts, RR: 0
Reply 2, posted (3 years 9 months 6 days 16 hours ago) and read 12094 times:

I don't think the 787's engine's had a hope of making promised spec 3 years ago, they needed the time as well.

User currently offlineA380900 From France, joined Dec 2003, 1116 posts, RR: 1
Reply 3, posted (3 years 9 months 6 days 15 hours ago) and read 11968 times:

Quoting queb (Reply 1):
GTF ? No delay announced for the GTF at this time

GTF was fist cancelled.

Quoting morrisond (Reply 2):
I don't think the 787's engine's had a hope of making promised spec 3 years ago, they needed the time as well.

Ok. I did not know that.


User currently offlinePlymSpotter From Spain, joined Jun 2004, 11672 posts, RR: 60
Reply 4, posted (3 years 9 months 6 days 15 hours ago) and read 11881 times:

They quite often are. The hold up for the SSJ-100 was largely due to delays with it's engines.


Dan  



...love is just a camouflage for what resembles rage again...
User currently offlinequeb From Canada, joined May 2010, 707 posts, RR: 3
Reply 5, posted (3 years 9 months 6 days 14 hours ago) and read 11747 times:

Quoting A380900 (Reply 3):
GTF was fist cancelled.

The PW8000 was a R&D project, not officialy launched.


User currently offlineBoeing4ever From , joined Dec 1969, posts, RR:
Reply 6, posted (3 years 9 months 6 days 14 hours ago) and read 11657 times:

Really? History is riddled with delays due to engines!

As mentioned, the SSJ100's current slippage is due to delays in certification of it's engines.

The 787? Both GE and RR are fortunate they had three extra years! The GEnx was off in its SFC targets and has been using the delay to catch up. RR had similar issues and when the 788 first flew two Decembers ago, it was with two newer RR Trent 1000's, with the original engines meant for first flight not being used at all, IIRC. They may have been sent back for modifications and returned to Boeing.

The recent explosion of a Trent 1000 on a test stand doesn't help matters, and has been cited as an impediment to 787 delivery progress, along with the myriad of self-inflicted hurdles that Boeing has. The Trent 900 issues on A380's shows that engine makers can cause headaches long after certification is complete!

The first 747s? Delayed due to P&W engine development issues.

The L1011? RR can largely take credit for knocking Lockheed out of the commercial business, with numerous deficiencies in the RB211 and ridiculous delays and overblown promises that they couldn't keep, handing the DC-10 the market. Eventually the RB211 would prove to be an amazingly reliable engine though, so don't forget that early troubles are not necessarily an indicator of future ills.

And those are just a few examples off the top of my head.

No, the engine makers do challenge themselves. The success of their company and the airframers can hinge on their products. The powerplants are as complex as the whole airframe itself! Hence why neither Boeing nor Airbus develop their own aircraft engines.

  B4e-Forever New Frontiers  


User currently offlineMir From United States of America, joined Jan 2004, 21691 posts, RR: 55
Reply 7, posted (3 years 9 months 6 days 13 hours ago) and read 11522 times:

Quoting Boeing4ever (Reply 6):
History is riddled with delays due to engines!

Another to add to the list:

The original A340 would have been a much better airplane had IAE been able to come out with the proper engines for it. But they weren't, as so Airbus had to make do with CFM.

-Mir



7 billion, one nation, imagination...it's a beautiful day
User currently offlineAesma From France, joined Nov 2009, 6728 posts, RR: 12
Reply 8, posted (3 years 9 months 6 days 12 hours ago) and read 11398 times:

I think the A318 engines were also a problem.


New Technology is the name we give to stuff that doesn't work yet. Douglas Adams
User currently offlinerfields5421 From United States of America, joined Jul 2007, 7607 posts, RR: 32
Reply 9, posted (3 years 9 months 6 days 12 hours ago) and read 11329 times:

New engine designs have historically suffered the same teething problems, overly optomistic production plans, etc as new design aircraft.

But often engine designs are just enhancements of existing modes, which tend to produce fewer problems during development.

Though like everything in aviation - there are many exceptions to any general statement.


User currently onlinelightsaber From United States of America, joined Jan 2005, 13267 posts, RR: 100
Reply 10, posted (3 years 9 months 6 days 12 hours ago) and read 11245 times:
Support Airliners.net - become a First Class Member!

Engines have the longest development time for an airframe. So often their delay is 'masked' by an early start. Often, until the engine development passes certain milestones, the airframe stays un-announced. One exception is the 787, but that was partially due to a longer needed airframe development time (due to the extensive use of CFRP and the new all electric nature of the airframe).

The 787 engines are a good example. Both GE and RR will miss fuel burn targets. RR's first engines will have to be ~50% scrapped and rebuilt with new parts, in particular a new low turbine, to help make the 787 do what it was promised to do.

The 748I engine benefited from the experience of the GP7200. Pratt taught GE a few tricks GE never thought Pratt would get ahead of them. Those benefits will then be incorporated into the GEnX-1B.

Quoting Boeing4ever (Reply 6):
The first 747s? Delayed due to P&W engine development issues.

In all fairness, Boeing/Pan Am demanded much more thrust than was being engineered for. It was too late for Pratt to increase the thrust easily when the engine vendor was informed of the higher thrust required by the 741.

A major example of a botched engine is the PW6000. By the time it came out, the A318 market was done.  

Lightsaber



Societies that achieve a critical mass of ideas achieve self sustaining growth; others stagnate.
User currently offlineCoronado From United States of America, joined Jun 1999, 1182 posts, RR: 2
Reply 11, posted (3 years 9 months 6 days 11 hours ago) and read 11169 times:
Support Airliners.net - become a First Class Member!

I think many could attribute the failure of the MD-11 to the performance issues, of the engines, particularly the PW4000's but also the GE's as the aircraft were way below promised range, and had higher fuel burn. By the time the performance improvement program was agreed upon with the engine manufacturers, the MD-11 was passed on by many prospective customers and in many ways the failure of the MD-11 can be said to have given some major market share impetus to the A330 family.


The Original Coronado: First CV jet flights RG CV 990 July 1965; DL CV 880 July 1965; Spantax CV990 Feb 1973
User currently onlineBMI727 From United States of America, joined Feb 2009, 15781 posts, RR: 27
Reply 12, posted (3 years 9 months 6 days 10 hours ago) and read 11000 times:

Quoting A380900 (Thread starter):
Except for the A400M and GTF, it feels like engines are never a problem in terms of development/production schedule

Ever hear of the 747?



Why do Aerospace Engineering students have to turn things in on time?
User currently offlineSchorschNG From Germany, joined Sep 2010, 500 posts, RR: 0
Reply 13, posted (3 years 9 months 6 days 10 hours ago) and read 11000 times:

Engines have the advantage of being easy to replace.
I doubt the RRs flying on the A380ies now are the same which were originally delivered.



From a structural standpoint, passengers are the worst possible payload. [Michael Chun-Yung Niu]
User currently offlinedfwrevolution From United States of America, joined Jan 2010, 984 posts, RR: 51
Reply 14, posted (3 years 9 months 6 days 10 hours ago) and read 10946 times:

The Ge90 was also delayed and quite problematic at EIS when it was first introduced on the 777-200.

User currently offlinefruitbat From United Kingdom, joined Dec 2006, 551 posts, RR: 6
Reply 15, posted (3 years 9 months 6 days 9 hours ago) and read 10233 times:

Quoting A380900 (Thread starter):
Except for the A400M and GTF, it feels like engines are never a problem in terms of development/production schedule. So I'm wondering: are the motorist really pushing themselves and taking risks? Or more or less doing always the same thing with very slow progress?

You should see it from the inside - engine development and production is a bit like a swan - calm and serene on the surface but paddling away like hell underneath!



Weaseling out of things is important to learn. It's what separates us from the animals ... except the weasel.
User currently offlineViscount724 From Switzerland, joined Oct 2006, 25653 posts, RR: 22
Reply 16, posted (3 years 9 months 6 days 9 hours ago) and read 10120 times:

Quoting BMI727 (Reply 12):
Quoting A380900 (Thread starter):
Except for the A400M and GTF, it feels like engines are never a problem in terms of development/production schedule

Ever hear of the 747?

But the engine issues didn't delay the first deliveries or entry into service, although there were many delays in the early months of service. Even Pan Am's inaugural 747 flight JFK-LHR was delayed several hours due to engine issues which required an aircraft substitution. That's why some sources show the inaugural flight as January 21, 1970 and others January 22. It was scheduled to leave January 21 but due to the delay and aircraft change it didn't finally leave until after midnight. (The aircraft that actually operated the inaugural was the one lost in the collision with the KLM 747 at Tenerife in 1977.)


User currently offlineUnitedTristar From , joined Dec 1969, posts, RR:
Reply 17, posted (3 years 9 months 6 days 9 hours ago) and read 10061 times:

Ask Lockheed about engine delays on the L1011 project!

-m

  


User currently offlineSEPilot From United States of America, joined Dec 2006, 6961 posts, RR: 46
Reply 18, posted (3 years 9 months 6 days 9 hours ago) and read 9955 times:

Quoting Coronado (Reply 11):
I think many could attribute the failure of the MD-11 to the performance issues, of the engines, particularly the PW4000's but also the GE's as the aircraft were way below promised range, and had higher fuel burn.

The MD-11 may have had engine issues at the outset, but the aerodynamic issues that were linked to MD's unwillingness to spend the money for a new wing are what killed the aircraft. They are the reason it is much more difficult to fly than any other airliner and has amassed a worse safety record than any other modern jet airliner.



The problem with making things foolproof is that fools are so doggone ingenious...Dan Keebler
User currently offlineNavigator From Sweden, joined Jul 2001, 1214 posts, RR: 14
Reply 19, posted (3 years 9 months 6 days 9 hours ago) and read 9933 times:

Quoting A380900 (Thread starter):
it feels like engines are never a problem in terms of development/production schedule

As some have already mentioned there have been delays from time to time in delivering properly functioning engines to new airplanes. The Boeing 747 comes to mind. Initially the whole ramp at Everett was filled with 747:s minus engines. And the Trent on the A380 still seems to have problems. I also think the SAAB 2000 had problems with the engines developed for that plane.

The more I think about it, the more I think that what you are saying is not really the case...



747-400/747-200/L1011/DC-10/DC-9/DC-8/MD-80/MD90/A340/A330/A300/A310/A321/A320/A319/767/757/737/727/HS-121/CV990/CV440/S
User currently offlineViscount724 From Switzerland, joined Oct 2006, 25653 posts, RR: 22
Reply 20, posted (3 years 9 months 6 days 9 hours ago) and read 9906 times:

Quoting Navigator (Reply 19):
The Boeing 747 comes to mind. Initially the whole ramp at Everett was filled with 747:s minus engines.

The 747 issues weren't entirely related to the JT9D engine itself. If memory correct the problems also involved the engine pylon design which caused the engine case to warp and resulted in the fan blades rubbing against the fan case.


User currently offlineNavigator From Sweden, joined Jul 2001, 1214 posts, RR: 14
Reply 21, posted (3 years 9 months 6 days 9 hours ago) and read 9802 times:

Quoting Viscount724 (Reply 20):
The 747 issues weren't entirely related to the JT9D engine itself. If memory correct the problems also involved the engine pylon design which caused the engine case to warp and resulted in the fan blades rubbing against the fan case.

Yes you are right. The case went oval...



747-400/747-200/L1011/DC-10/DC-9/DC-8/MD-80/MD90/A340/A330/A300/A310/A321/A320/A319/767/757/737/727/HS-121/CV990/CV440/S
User currently offlinefaro From Egypt, joined Aug 2007, 1556 posts, RR: 0
Reply 22, posted (3 years 9 months 6 days 7 hours ago) and read 8855 times:

And the A340 was let down by the late SuperFan which died prematurely whilst still on the drawing board. Had it been successful, the A340 vs 777 long-haul battle could have turned out quite differently.

And then there's the case of the emissions problems of the PW4098 which, like the PW6000, became a mono-customer engine...

Faro

[Edited 2011-01-22 14:51:27]

[Edited 2011-01-22 15:01:58]


The chalice not my son
User currently onlinelightsaber From United States of America, joined Jan 2005, 13267 posts, RR: 100
Reply 23, posted (3 years 9 months 6 days 4 hours ago) and read 7491 times:
Support Airliners.net - become a First Class Member!

Since everyone is beating up on Pratt, don't forget:

On the 757, RR had to recall *all* engine after re-introducing a better (lower fuel burn) design. In the long term it paid off...

L1011, the composite fan issues delayed the program. Between that and the *long* RR strike, it killed off the chances of the L1011 vs. the DC10. Just imagine if the L1011 hadn't entered service a year behind the DC10...   

The original GE-90 had quite a few issues. (e.g., Saudia had a cabin filled with jet fuel fumes on the ground) before they abandoned the double row lean burn annular combustor for a conventional (higher emission) single row combustor. Luckily for Boeing, it wasn't the launch engine...   (Pratt did the PW4084 right. They do deliver)

it wasn't until a few years ago that the CF-6 on the A330 had decent hot high.

Quoting faro (Reply 22):
And then there's the case of the emissions problems of the PW4098

PW4098 had a fuel burn issue. It was supposed to burn 2% less fuel than the PW4090 and instead burned 2% more. Even with the added thrust, a 773 has more payload at range with PW4090s than PW4098s on most days.

The PW4090 had an emissions issue that prevented it from being up-thrusted.

The PW6000 missed fuel burn by an incredible amount, 7%.

Quoting faro (Reply 22):
And the A340 was let down by the late SuperFan which died prematurely

Pratt discovered there were issues with a gearbox in a jet engine. Every turbine manufacturer has been trying to develop a gearbox as the benefits of a GTF have been well known for a long time. It is now 30 years later and we're finally going to see a GTF.

Quoting Viscount724 (Reply 20):
If memory correct the problems also involved the engine pylon design which caused the engine case to warp and resulted in the fan blades rubbing against the fan case.

They were all releated to a 'late in the game' thrust requirement increase. That always creates problems.

But, for a time, a large number (25 IIRC) of new 741s were sitting out on the taxiways waiting for Pratt engines in addition to the in service issues.

Neil



Societies that achieve a critical mass of ideas achieve self sustaining growth; others stagnate.
User currently offlinewn700driver From , joined Dec 1969, posts, RR:
Reply 24, posted (3 years 9 months 6 days 4 hours ago) and read 7266 times:

Quoting A380900 (Reply 3):
GTF was fist cancelled.

Ouch, is that like what happens to my nose when I get a punch in the face?!

Seriously though, as many have said, engines are late all the time, often for good technical reasons, as they are immensely complex items.


25 jgw787 : Engines are usually delayed...unless the manufacture includes time for delays in it projected time
26 A380900 : Eating crow... Are we certain the GTF is going to be a success? There could be tons of problems once it goes into service. Also if PW is the only one
27 cf6ppe : The engine had to have a thrust frame added which connected the aft engine mount around the compressor to the bottom at the front of the compressor a
28 Stitch : I believe Rolls-Royce has been working on one, as well, and Airbus was hoping that the two would combine forces through IAE to develop a model for th
29 thegeek : Umm, did SEPilot say anything incorrect or poorly put?
30 Post contains images lightsaber : Pratt is holding back quite a bit of fuel burn 'just in case' they miss promise. So there is every reason to believe it will be a success. For exampl
31 A380900 : Why would Airbus prevent them from offering something? If RR wants a piece of the action on the A320 Neo, they can offer to pay for testing. Why woul
32 Stitch : Time to Market. None of RR's narrowbody propulsion programs - GTF or triple-spool - will be ready by 2016 when the A320neo is scheduled to EIS. I am
33 faro : In all fairness, I wish the PW1000 GTF all the world-beating success of the JT3D and JT8D. PW took considerable industrial and financial risks in its
34 Post contains images lightsaber : It will be nice to see the eagle again on a narrowbody. It will take some time for big GTFs, the heat generated is not linear. Cooling of the gearbox
35 packsonflight : Is this because PW bad reputation of delivering as promised?[Edited 2011-01-23 09:53:40]
36 lightsaber : Of Pratt's latest engines. They did well on the PW4084 and PW4090. They also did very well on the PW4168. Then they botched: PW4098 PW4173 which was
37 prebennorholm : The first two generations or jet airliners were based on off the shelf military engines or slightly modified military engines. Plane manufacturers jus
38 tdscanuck : Besides not making time to market, there is considerable cost to maintaining (yet another) engine type on an airframe. Unless RR is going to pay for
39 packsonflight : I always thought that the GTF was the only engine possible to mate with the 737 to extract sufficient fuel burn improvements to justify such a progra
Top Of Page
Forum Index

This topic is archived and can not be replied to any more.

Printer friendly format

Similar topics:More similar topics...
Why Are National Flags Backwards On MH Aircraft? posted Tue Aug 14 2007 11:30:45 by Fly2CHC
Why Are AFs Seats Different On Long-haul Aircraft? posted Tue Jan 23 2007 16:42:44 by 8herveg
Why Are The 747-777 On Domestic In Japan? posted Fri Dec 15 2006 02:01:00 by Montenegro
Why Are United's Boeing's Always 7x7-x22 posted Fri Oct 13 2006 05:41:49 by United787
Why Are Underwing Engines Slung Forward? posted Mon Apr 10 2006 08:11:30 by Remcor
Why Are Aircraft Types Printed On Aircraft? posted Thu Mar 18 2004 01:52:45 by Richard28
Why No New BF Seats On CO 767-400/-200? posted Tue Dec 30 2003 18:15:59 by Transtar
FR: Why Do Taxes Vary Depending On Time Of Flight? posted Sun Aug 10 2003 12:14:38 by Pe@rson
Why Are People So Picky On Airlines? posted Thu Mar 28 2002 07:47:04 by Fly_emirates
Why Are There Missing Windows On Our 73G's? posted Tue Feb 19 2002 21:49:06 by SJCguy