Search found 32 matches

by Carmitage
Tue Jun 11, 2019 6:20 pm
Forum: Civil Aviation
Topic: Confirmed: 777X First Flight Delayed Due GE9X Issues
Replies: 300
Views: 66843

Re: Rumour: 777X First Flight Likely Delayed to Year End Due GE9X Issues

Reading a lot of comments, I get the impression that the 779 won’t sell. If an airline needs the capacity and is able to fill it, they will buy the plane. And how “superior” it will be to the A35K remains to be seen. Time will tell. Thing is, blue chip carriers like BA, CX, QR and EY have found roo...

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by Carmitage
Tue Jun 11, 2019 10:07 am
Forum: Civil Aviation
Topic: Confirmed: 777X First Flight Delayed Due GE9X Issues
Replies: 300
Views: 66843

Re: 777X First Flight Delayed to Year End Due GE9X Issues

Better tell all the other airlines that went GE too, there is a reason they are the leading engine on the 787. Airlines don't play Top Trumps. The RB211 on the 757 burns anywhere from 4-8% more than the Pratt (depending on mods) yet it still had more customers. The GTF on the neo has an appreciable...

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by Carmitage
Tue Jun 11, 2019 9:45 am
Forum: Civil Aviation
Topic: Confirmed: 777X First Flight Delayed Due GE9X Issues
Replies: 300
Views: 66843

Re: Rumour: 777X First Flight Likely Delayed to Year End Due GE9X Issues

If GE invested so much in the GE9x there would pressure to get significant ROI and the 777X program, as it looks now, won't offer that. Probably they will go for a GENX upgrade using new technology, to become available around 2025, like the geared Ultrafan. Some people may have made a similar comme...

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by Carmitage
Thu Jun 06, 2019 1:47 pm
Forum: Civil Aviation
Topic: Airbus to launch longer range A321 and not chase market share
Replies: 116
Views: 35407

Re: Airbus to launch longer range A321 and not chase market share

Airbus has 11.5 rate months per year on the A320 (and 11 on the WBs),

so annual rate 60 on A320 = 11.5 x 60 = 690 (and rate 63 is 724 annually).
Rate 10 on the A350 is 11 x 10 = 110 per year

No idea why (maybe the WB FAL has two weeks more holiday?)

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by Carmitage
Mon Jun 03, 2019 7:00 am
Forum: Civil Aviation
Topic: Pratt & Whitney reduces life limits for A220, E190/E195-E2 engines
Replies: 30
Views: 7950

Re: Pratt & Whitney reduces life limits for A220, E190/E195-E2 engines

Sounds a similar problem to the Trent 1000 (as mentioned above) - how come that cost RR £1.5bn and yet everyone so far on this topic is so relaxed that it isn't a big deal for P&W. What is different?

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by Carmitage
Thu Apr 25, 2019 7:24 am
Forum: Technical/Operations
Topic: Narrowbody vs widebody costs trans Atlantic
Replies: 58
Views: 9193

Re: Narrowbody vs widebody costs trans Atlantic

As has been mentioned - it is not simple: 1) as you get towards the outer end of the NB range, it can carry less passengers a) MTOW constrained, the fuel tanks brimmed, less weight left over for payload b) may be an element of even if not MTOW constrained, at max range, simply cannot carry a full lo...

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by Carmitage
Thu Apr 11, 2019 6:53 am
Forum: Civil Aviation
Topic: B737MAX Grounded Worldwide Q1 2019
Replies: 6472
Views: 715982

Re: B737MAX Grounded Worldwide

Across a fleet, I've seen numbers of 5E-5; around once every 20,000 flight hours. Which begs the question, do we have an estimate or actual data for how many flight hours the MAX has accumulated? There were some lively discussions up thread when we were still arguing over whether the MAX should be ...

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by Carmitage
Tue Apr 09, 2019 9:37 am
Forum: Civil Aviation
Topic: B737MAX Grounded Worldwide Q1 2019
Replies: 6472
Views: 715982

Re: B737MAX Grounded Worldwide

Is there not a way of removing MCAS altogether then? By simply adding ballast and moving the CoG to where it should be, so it behaves like an NG. MCAS is now known publicly as a stall-protection system, that does not work. No amount of PR spin from Boeing will ever change that. Remove it completely...

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by Carmitage
Mon Apr 08, 2019 6:58 am
Forum: Civil Aviation
Topic: What does it take for an airline to change an aircraft engine type?
Replies: 16
Views: 2715

Re: What does it take for an airline to change an aircraft engine type?

OR - is this question about what would it take for an airline to change engine manufacturer for its next order? In that case, it is usually underperformance of the existing engine/not feeling the love from the OEM and/or the other engine OEM REALLY wanting the business. Emirates switching to RR from...

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by Carmitage
Tue Apr 02, 2019 2:15 pm
Forum: Civil Aviation
Topic: Two SIA 787s grounded owing to Trent 1000 TEN HPT issue
Replies: 65
Views: 17928

Re: Two SIA 787s grounded owing to Trent 1000 TEN HPT issue

Ooops, got my signs the wrong way round

should be >180, not <180

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by Carmitage
Tue Apr 02, 2019 2:14 pm
Forum: Civil Aviation
Topic: Two SIA 787s grounded owing to Trent 1000 TEN HPT issue
Replies: 65
Views: 17928

Re: Two SIA 787s grounded owing to Trent 1000 TEN HPT issue

The Trent 1000 is currently running at IFSD of about 0.2/100,000 hours (pretty similar to the GEnx), the GTF is running at 1/100,000 hours - five times worse and at the ETOPS<180 limit - why exactly do Airbus need to get into bed (or kissy face) with PW with a larger GTF?

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by Carmitage
Fri Mar 29, 2019 7:49 am
Forum: Civil Aviation
Topic: WTO rules against Boeing and US.
Replies: 22
Views: 5801

Re: WTO rules against Boeing and US.

As I understand it, the gripe is the following: On one hand, Europe LENDS Airbus billions - this is allowed under the rules, but only at a commercial interest rate. The loan is then repaid (with interest) on delivery of the aircraft. If the EXPECTED number of aircraft are not delivered, the remainde...

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by Carmitage
Fri Mar 15, 2019 4:15 pm
Forum: Civil Aviation
Topic: B737MAX Grounded Worldwide Q1 2019
Replies: 6472
Views: 715982

Re: B737MAX Grounded Worldwide

Ok, let’s assume that the FAA gives Boeing the all clear with the software upgrade, but CAAC or EASA say “that’s fine, but not in my airspace”, doesn’t that mean that the FAA has lost its preminent position as certifying authority? Presumably to avoid this risk, they will only go ahead with the agre...

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by Carmitage
Fri Mar 15, 2019 2:22 pm
Forum: Civil Aviation
Topic: The folding wings of the B777-9
Replies: 92
Views: 18454

Re: The folding wings of the B777-9

That 747 - Rolls-Royce engines were clearly to blame (probably the Trent 1000, at that)

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by Carmitage
Thu Feb 21, 2019 7:00 am
Forum: Technical/Operations
Topic: Future engine improvements
Replies: 32
Views: 3315

Re: Future engine improvements

My thermodynamics was a long time ago (and I wasn't very good at it then), so a) I was illustrating the point, but b) it should be the exit temperature of all the gas (as the LPC has converted some of the core gas temperature into energy in the bypass air), shouldn't it? I guess it should be somewhe...

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by Carmitage
Wed Feb 20, 2019 4:56 pm
Forum: Technical/Operations
Topic: Future engine improvements
Replies: 32
Views: 3315

Re: Future engine improvements

Couple of points that, I believe, need clarification - CMCs do help with temperature, but really we are approaching the upper bounds of benefit due to: 1) NOx formation - the black art of combustion is to have the highest average temperature in the combustion chamber, with no hot spots to form NOx 2...

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by Carmitage
Wed Feb 20, 2019 4:33 pm
Forum: Technical/Operations
Topic: Future engine improvements
Replies: 32
Views: 3315

Re: Future engine improvements

Couple of points that, I believe, need clarification - CMCs do help with temperature, but really we are approaching the upper bounds of benefit due to: 1) NOx formation - the black art of combustion is to have the highest average temperature in the combustion chamber, with no hot spots to form NOx 2...

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by Carmitage
Thu Jan 24, 2019 5:14 pm
Forum: Travel, Polls & Preferences
Topic: CMCs and fuel efficiency question
Replies: 0
Views: 323

CMCs and fuel efficiency question

I’m trying to figure out how much an efficiency benefit CMCs in the hot end of an engine might give My thought process so far is the two benefits (from a fuel burn perspective) are 1) thermal efficiency 2) 10% of compressed air goes on cooling the blades/stators Thermal efficiency = (T hot - T cold)...

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by Carmitage
Wed Dec 19, 2018 4:34 pm
Forum: Civil Aviation
Topic: A220 Longer term Impact on Airbus Strategy, the Canadian Connection
Replies: 66
Views: 9478

Re: A220 Longer term Impact on Airbus Strategy, the Canadian Connection

FWIW, there will not be any tariff issues post Brexit as both the EU and UK are both signatories of the WTO Civil aircraft agreement (along with 32 other countries/entities) allowing tariff free trade between those countries - the big issue was EASA refusing to certify non-EU parts (despite Airbus s...

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by Carmitage
Thu Dec 06, 2018 7:58 am
Forum: Civil Aviation
Topic: Is Airbus hiding a new A322 business case behind the 100t+ A321XLR study? Numbers..
Replies: 211
Views: 28003

Re: Is Airbus hiding a new A322 business case behind the 100t+ A321XLR study? Numbers..

I'm not sure it really matters whether the A322 would be competitive vs the 797 - neither have been launched. If Boeing needs (say) 2,000 797 to make an attractive return and the A322 could take (say) 200 of those deliveries, that might be enough to tip Boeing from launching the 797 to not launching...

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by Carmitage
Wed Nov 28, 2018 2:42 pm
Forum: Civil Aviation
Topic: Bloomberg: Airbus considering A330NEO Regional
Replies: 95
Views: 16687

Re: Bloomberg: Airbus considering A330NEO Regional

Lightsaber - with respect (and it is 30 years since my aerospace production engineering days), it seems to me that with increased automation, learning curves will reduce, not increase, so I would question that 13% you refer to, which seems to be in line with Wright's (1936) or Yelle's (or Stanford-...

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by Carmitage
Wed Nov 28, 2018 8:15 am
Forum: Civil Aviation
Topic: Bloomberg: Airbus considering A330NEO Regional
Replies: 95
Views: 16687

Re: Bloomberg: Airbus considering A330NEO Regional

Lightsaber - with respect (and it is 30 years since my aerospace production engineering days), it seems to me that with increased automation, learning curves will reduce, not increase, so I would question that 13% you refer to, which seems to be in line with Wright's (1936) or Yelle's (or Stanford-B...

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by Carmitage
Tue Nov 27, 2018 1:48 pm
Forum: Civil Aviation
Topic: Airbus - hiring for new narrowbody and A350 neo
Replies: 160
Views: 25752

Re: Airbus - hiring for new narrowbody and A350 neo

Couple (OK, 3) of points: 1) has anyone actually seen an advert that mentions an A350neo? The A350 advert above talks about beyond the -1000, including domestic and regional. It seems to me that might need less than 84k lbs thrust, so maybe another engine? Therefore not a neo to improve on the exist...

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by Carmitage
Fri Oct 12, 2018 10:25 am
Forum: Civil Aviation
Topic: Scoot 787-9 suffers from an engine failure while on approach to Perth
Replies: 7
Views: 5175

Re: Scoot 787-9 suffers from an engine failure while on approach to Perth

I heard (from an admittedly non-unbiased source) that the GEnx has suffered as much (Ethiopia having over 200 engine removals on their 10 or so 787s over 4 years). However, GE has been much better at a) supplying spare engines; b) keeping it quiet/out of the public eye and c) many of these problems ...

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by Carmitage
Tue Oct 09, 2018 5:16 pm
Forum: Civil Aviation
Topic: Why didn't BA order the B748?
Replies: 101
Views: 30485

Re: Why didn't BA order the B748?

They were going to order the 747-8i, but the final offer they got on the GEnx engines was so appalling they switched to the A380 instead. It wasn't commonality or adoration of RR engines. The offer was, apparently, so bad that they believed GE was trying kill the entire programme (remember, the orig...

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by Carmitage
Tue Oct 09, 2018 5:16 pm
Forum: Civil Aviation
Topic: Why didn't BA order the B748?
Replies: 101
Views: 30485

Re: Why didn't BA order the B748?

They were going to order the 747-8i, but the final offer they got on the GEnx engines was so appalling they switched to the A380 instead. It wasn't commonality or adoration of RR engines. The offer was, apparently, so bad that they believed GE was trying kill the entire programme (remember, the orig...

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by Carmitage
Fri May 04, 2018 3:51 pm
Forum: Civil Aviation
Topic: British Airways in talks to order Boeing Widebodies
Replies: 170
Views: 35027

Re: British Airways in talks to order Boeing Widebodies

Two scenarios 1) In order to prove a point to RR, they go to GE 2) in order to squeeze more compensation out of RR, they dangle a tasty order in front of their noses, with the unwritten threat that if they are not reasonable to their customer's grievances, there is always another willing engine supp...

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by Carmitage
Fri May 04, 2018 8:38 am
Forum: Civil Aviation
Topic: Airbus Cuts Production Plans for A330 Jet
Replies: 229
Views: 27745

Re: Airbus Cuts Production Plans for A330 Jet

A few points: 1) the A330neo is a cheap to develop aircraft - it doesn't need to sell many aircraft to cover its development costs (I reckon it has covered its development costs with its current backlog - anything more is upside) 2) There is a competition going on between Airbus and Boeing (in case ...

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by Carmitage
Thu Mar 22, 2018 1:14 pm
Forum: Civil Aviation
Topic: The only picture ever taken of Concorde flying at Mach 2
Replies: 70
Views: 17899

Re: The only picture ever taken of Concorde flying at Mach 2

The effortlessness is right - there is a nice story about an SR-71 presentation, saying that the Blackbird had done more supersonic hours than the rest of the world's aircraft. They were then corrected by a Brit (or maybe Frenchman) saying that Concorde had done more supersonic hours than all the re...

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by Carmitage
Thu Apr 27, 2017 12:45 pm
Forum: Civil Aviation
Topic: BEA investigating Air France take offs at Bogotá - only 5 ft. over threshold
Replies: 114
Views: 26223

Re: BEA investigating Air France take offs at Bogotá - only 5 ft. over threshold

I think it is the other way round - twins climb MUCH faster than quads in normal operation, because legally they have to have over 100% excess thrust (so if one engine goes down, they can still climb away safely), whereas a quad only needs over 33% excess thrust (so if one engine goes down, they can...

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by Carmitage
Thu Apr 06, 2017 11:06 am
Forum: Civil Aviation
Topic: Drone comes within an alleged 300 feet of a Singapore Airlines A359 performing a flyby in Perth
Replies: 7
Views: 2640

Re: Drone comes within an alleged 300 feet of a Singapore Airlines A359 performing a flyby in Perth

could be a perspective thing - the diameter of the A350 fuselage is 22mm on my screen and the drone is 5mm wide. The actual diameter of the A350 is about 6m, so that would imply the drone is 1.36m wide if at the same distance. It looks like a DJI Phantom, which is about 350mm diagonal, so that would...

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by Carmitage
Tue Jan 17, 2017 1:39 pm
Forum: Civil Aviation
Topic: Boeing 787-9 <-> Airbus A330-900 Competition
Replies: 656
Views: 108657

Re: Boeing 787-9 <-> Airbus A330-900 Competition

As far as I've read, this thread seems to be missing one critical factor - price. I'd argue that "better" means "offers better economics to the airline" (on a risk adjusted basis) According to John Leahy, the A330neo will be $20-25m cheaper than the equivalent 787, or roughly 20%...

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