Emirates asking for A380 engine enhancements

Emirates obviously wants some enhancements for their A380 engines - at least for the aircraft that should one day replace the first ninety. The last of these aircraft will be delivered in 2017 and by that time Airbus will have delivered around 240 A380 if all production slots are filled until that time. Well, obviously some of the ordered aircraft will be either delivered later as their deliveries are deferred (like for Virgin Atlantic) of won't be delivered at all (read: Kingfisher and probably Hong Kong Airlines as well as Air Austral).
Two engine manufactures share the A380 market: Rolls Royce and the Engine Alliance (50:50 JV between GE and P&W). Let's say both have around 50% of the market (actually, thanks to the large Emirates orderbook EA has a slight lead), then both manufacturers will have delivered 480 engines plus spares.
Now Emirates asks for a "propulsion technology crossover into the A380, in terms of what they’re doing on the 777X, the A320neo and the 737MAX”, says Emirates president Clark and claims that one of the EA partners will produce "wonders in propulsion technology" by 2020, when the A380 still should have GP7200 engines (and the Trent 900 of course as well). So he asks what the plans from GE and P&W are to improve propulsion efficiency of the GP7200.
my first question would be who of the two EA partners will produce these "wonders"?

• Does he refer to the GE9X? He should have a good knowledge about what GE is planning for this engine, although some questions arose around his comment that the engine would need water injection to be able to lift the B777X from Dubai year-round: read the first reaction from GE here, another one here. Clearly, the GE9X will be the state-of-the-art engine in it's class, encompassing the Trent XWB-97, as overall pressure ratio and bypass ratio will be higher and the use of CMC should save some cooling air, further elevating the core efficiency compared to the latest Trent engine.
• Or does he refer to the Geared Turbo Fan from P&W. From all what we know this engine defines the segment of the regional and  narrowbody engines for the years to come (closely followed by the LEAP engine family, of course).

Nevertheless which engine concept Clark has in mind, I wonder if the two partners in the EA are ready for a big improvement programme for the GP7200. Small improvements have already been made: today's GP7200 are better by 2% than original spec values. To improve the engine by any big (SFC percentage) number should be at least very costly, if not impossible without a change in architecture. But with only about 500 engines of the GP7200 sold by then there would be no hope for the engine program to ever produce a profit. So EA (as well as RR) will do whatever they can to avoid another large development investment in the engine. RR could on the other hand also offer a downrated Trent XWB, although this engine might be too heavy for the wing as it is today.
Last week , there was speculation in a german newspaper about what might be the A380 going forward plan from Airbus. Günter Butschek, Airbus COO speculated about "modifications" for the aircraft, Heinrich Großbongardt, a german aviation consultant, speculated about an A380neo. I guess in Hartford, Cincinnati and Derby this was not a fun-to-read...

Paris Air Show 2011

That was quite an event! I will focus on just some of the most important topics here, the most important of course being

A320NEO

1029 order and commitments! (plus a few more options) - Never ever in history there was an aircraft selling so fast. Of course, a comparison to the B737NG is unfair, as 15 years ago we did not have such big and emerging markets in China, India and all over Asia (more than 460 A320neos are ordered by Asian airlines so far). Also I am sure that a reengined B737NG or a NSA/B797 would sell as good as the A320NEO (or in the case of the – hypothetical – B797 even better). But let us roll back one year: there were many skeptics of the A320neo, saying that demand for such a “warmed-up” aircraft would just not be there. Others said that Airbus might be forced to convert many of the orders for the current A320 to the –neo model. Both are proved wrong today. Even Air Asia boss Tony Fernandes did not manage to convince John Leahy to convert some of the old orders to the –neo.

Now if American Airlines would really decide to order 100 A320neo (probably they are most interested in the A321neo) this summer, there would be lots of activities starting in Chicago and Seattle.

The A320neo brings us right away to the next big topic at this year’s Airshow.

LEAP-1A vs. PW1100G

Before I get started, please read what Addison Schonland wrote in his piece on AirInsight. As I laid out before I have my doubts about the performance claims of the LEAP-1A. And as I heard, CFM did more PW1100G-bashing at his media briefing just ahead of the Airshow than talking about their own product and it’s merits. A rock solid confidence looks different…

Nevertheless, CFM managed to get large deals at the Airshow. The largest, of course, was the order for 400+ engines for the 200 aircraft deal of AirAsia. But this was CFM’s to loose, as they are providing the CFM56 for the current 175 aircraft order from AirAsia, GE won with the CF6-80 for AirAsia’s A330-200 just recently and GE became a sponsor of Tony Fernandes F1 Lotus Team.

I did a prediction about A320neo orders and the respective engine choices just a week before the Airshow opened. I was wrong at SAS and Republic – both choose the LEAP-1A over the PW1100G. As it appears, I underestimated the market power of CFM, GE and GECAS.

I also expressed before that I think there could be an alliance between Airbus and CFM to keep potential CSeries customers away from ordering the Bombardier aircraft by giving them deals they cannot deny. This strategy can work with airlines which have business with CFM, GE and/or GECAS today.

Look at Republic: the whole Frontier fleet is powered by the CFM56 today - about half of the A319 fleet from Frontier is leased through GECAS.

Republic has the largest Embraer EJet fleet in the world, all powered by the CF34-8/-10. Most of the E170 in the fleet of Republic Airlines, one of Republics subsidiaries, is leased from GECAS.

So GECAS, CFM and GE have all possibilities to sweeten the LEAP-1A deal with discounts on spare parts and leasing rates – one thing that Pratt&Whitney can not do.

SAS on the other hand is a large B737NG customer and they also have a CRJ900 fleet powered by the CF34-8. They choose 2^nd hand B737-700 over the CSeries earlier this year. This decision was probably more cash driven, as leasing rates for used aircraft are of course cheaper than for new ones and SAS is going through a tough time right now. SAS has also A319 and A321’s in their fleet, powered by the IAE V2500. But firstly the V2500 powered fleet is much smaller than the B737NG fleet, and secondly, PW always has to deal with Rolls Royce on the V2500 business. And as RR has no stakes at all in the –neo business, they have no interest in building a bridge for PW at all.

One A320neo deal that did not materialize in Paris was the anticipated order for 50 aircraft from Qatar (as well as the “deferred” CSeries order). The A320neo will come one day of the other, just as U-Turn Al’s mood allows, but I guess the chances for the PW1100G are better here.  Although GE can throw their GGE90-115B business on the B777-300ER/-200LR fleet here (Qatar just ordered 6 more of them in Paris) and CFM powers 4 A340-300 in Qatar’s fleet, the A320 fleet is powered by the V2500 and PW might to persuade Qatar by making good deals on both the CSeries and the A320neo.

CSeries

John Leahy still thinks that Bombardier should scrap the CSeries program. As an Airbus employee he has to say that, regardless of what he thinks.

But as in the weeks before and at the Airshow there were five new customers announced (three of them unnamed so far), I think it became clear  that a growing number of airlines got convinced that in this market segment an optimized aircraft is better suited than, say an A319neo. Surprisingly, the CS100 got the biggest chunk of the new orders – maybe something to think about at Embraer…

I guess we will see a few other orders for the CSeries until the end of the year:

- Delta Air Lines

- Qatar (finally)

- GoAir, which just ordered 72 A320neo, hinted for a “raft” of CSeries soon to order

Boeing

Boeing did not raise the bar very high in the run-up of the Airshow, but did extremely well with orders, especially on the widebody front. It remains to be seen, if the revised A350-1000 can break the monopoly the B777-300ER enjoys in their segment. A stretched A350-1100X was denied by Airbus officials, but we will see…if the Rolls Royce managers are wise, they build in another 5% thrust margin above the 97klbf in their revised Trent XWB nacelle lines to cover for growth.

Scott Hamilton further explains Boeing’s success – I suggest to read his entry for more.

Other stuff

There was lots of other stuff to talk about – but I won’t, at least for today…

A350-1000 with more range - Update

Flightglobal has a new take on what is going on with the A350-1000. Contrary to Scott Hamilton, Max Kingsley-Jones thinks that the wing would be part of the design change, thus getting larger. This could indicate two things:
1. The Thrust/Weight-Ratio could get down without sacrificing runway performance as the larger wing would provide more lift. In other words, the MTOW could be lifted more than the ~5% gain in takeoff thrust, enabling the aircraft to carry more payload (especially cargo) over the reportedly new design range of 8500nm.
2. The investment for a larger wing and a "new" engine would make more sense, if another type would be added to the A350 family - call it the A350-1100 for now. With a further stretch of 4m it would have a fuselage length of roughly 80m, representing the ultimate stretch and would be a real B777-300ER competitor in terms of passenger capacity. The question then only is, if the range of the -1100 would be limited to 8000nm, comparable to the B777-300ER range, or if the -1100 would also get a range suitable for LAX-DXB (I now think that the 8500nm should work in >90% of the time for that route). If so, the "new" engine should really be a "new" engine - not just with an enlarged core, but also with a larger fan, as the thrust requirement would be more in the range of 105klbf. That would have implications to the basic design of the aircraft, especially the length of the undercarriage.

So Airbus could end up with the sub-families fo the A350 - the -900 and the -800 on the lower end and the -1000 and the -1100 on the upper end, very much comparable with the A340.

But again - until June 18 all is about speculation! But that's the fun with it...

A350-1000 with more range - implications for B737 successor?

Scott Hamilton just came out with this story: the A350-1000 will get more range (500nm) and a more powerful Trent XWB engine (+5000lbf).
A quick calculation revealed that 500nm more range need about 12.3t more MTOW. About 10 tonnes are for the extra fuel burned to cover the extra 500nm, about 2 tonnes needs the structure to carry the heavier aircraft, the balance goes for fuel reserves, as these are calculated in dependence of the actual flown range.
Thrust-to-weight ratio thus will be largely unchanged, runway performance probably a little bit worse, if the wing is unchanged. Compared to the B777-300ER, the wing is not heavily loaded, so I do not believe Airbus will enlarge the wing.
Scott writes that even the 8500nm will not meet Emirates desire of being able to fly Dubai - Los Angeles nonstop. The great circle distance for DXB-LAX is about 7250nm, so there is a 17% range margin. But is this enough to counter strong headwinds. A quick calculation shows that 17% of Ma0.85 (cruising speed of the A350) are equal to about 83nm/hr, meaning that if the average headwind on the route is higher than 83 knots, a technical stop would be necessary. I do not the average wind speed on the route over the north pole, but I could imagine that average wind speeds of 83knots and more ar possible.
The calculation also confirms that Emirates second desire - to add more pax - cannot be part of the change in the A350-1000 specification. So I wonder what is the rationality behind these changes? The 777-300ER has slightly less than the 8000nm of the "old" -1000 configuration, the 500 extra miles is good for a couple of extra city pairs, but does that justify the pain? The pain is probably bigger for RR than for Airbus, as these 5000lbf more of thrust will very likely mean that the whole core has to be changed, which means a lot of investment.
The main reason for that change might be to prevent Boeing from concentrating on the B737 successor. Airbus might hope that Boeing now feels more pressure on the B777-300ER and to concentrate R&D resources here and "only" to re-engine to B737 as Airbus always predicted.
And Airbus is apparently not alone: the recent Bernstein Research Note also suggests that Boeing should re-engine. Richard Aboulafia, VP of Teal Group, also thinks that a B737RE is the best answer to the A32XNEO, as one can reread in the AirInsight Paris Airshow Discussion transcript.
I guess we can expect the official Airbus announcement on Saturday, June 18th at the press briefing.
One is for sure - this years Paris Air Show is getting more and more interesting.

EASA Directive for Trent 900

The EASA found an oil fire in the HP/IP turbine area to be the cause of the uncontained failure in the #2 Trent 900 engine of the Qantas A380 on Nov. 4. This is an outcome that was expected by experts. The AD dated November 10, 2010 can be found here.
But why does an oil fire lead the IP turbine disk to disintegrate? Let's talk about what (likely?, maybe?) happened in detail and step by step:

1. The buffer cavity between the HP and the IP gets contaminated with oil. Why this happened is pure speculation at the moment. It could have been a bearing that leaked, it could have been oil lines that leaked or failed or something else...
2. During the take-off and climb phase temperatures in the cavity are rising high enough to let the oil ignite.
3. The IP shaft gets overheated and fails.
4. The IPT disk, now running free without the IP compressor as a brake, accelerates in milliseconds as fuel is still pumped into the combustor. The bore of the disk is designed to withstand speeds that are up to, say, 40% higher than the speed at takeoff, whereas the airfoils are designed to fail earlier, at maybe 120% speed. But the oil fire also heated up the bore, decreasing the so called overspeed burst margin.
5. The disk burst at a speed before the airfoils fail.

So what needs RR to do to prevent such a failure to happen again?

First of all, prevent the oil leakage. Without oil leakage no fire, no shaft shear, no disk burst.
Secondly, as you probably never can eliminate the possibility of an oil leak for 100% sure, a functionality has to be build into the engine that detects a shaft shear and shuts off the fuel immediately. Without the fuel being burned and the energy put into the turbine gas path, the disk will not accelerate.

Rolls Royce said that the Trent 900 and the Trent 1000 uncontained failures are unrelated. That might be true with respect to the causes of the two incidents. But I would like to hear what Rolls Royce changed in their design philolosophy between the Trent 900 and the Trent 1000 (and the Trent XWB) to prevent such an overspeed beyond burst limit speeds in case of a shaft shear as it appears that the outcome of the different causes was the same.
To clarify, the story I pictured is my view on what might happened. I can't assure that it was like I wrote. I hope to hear the "real" story tomorrow from RR.

The Qantas A380 engine failure - a disaster for Rolls Royce?

A first serious incident happened with an A380 – the first Qantas A380, registered VH-OQA, made an emergency landing in Singapore, not long after taking off from the same airport.

Pictures show that the aft part of the No.2 Trent 900 nacelle is missing. Eye witnesses from the ground said that there was a loud bang (or explosion) and trails of smoke after that.

All this points to an uncontained failure. In recent months we saw two other uncontained failures in RR engines – first a RB211, also with Qantas, but on a B747-400 and then the Trent1000 on a testbed in Derby.

If at least the Trent1000 failure and the -so far- suspected failure in the Trent 900 of the A380 are in any conjunction remains to be seen. At least it is not good publicity for Rolls Royce in a time that is not easy for the No.2 engine maker:

• Deliveries of the Trent 900 are, due to the production problems and slow ramp-up of the A380, not in numbers that were anticipated in the business case. Any profit from this engine program is delayed by years (the same is also true for the GP7000, of course).
• Even heavier probably , the Trent 1000 drags on profit margins. The 787 is late by almost three years – if the first delivery in mid-February will be met. According to the original ramp-up plan, there should have been around 200 B787 in service by now, maybe half of if powered by the Trent 1000. The performance inprovement programs, aimed to meat the promised fuel burn at the aircraft probably doubled development costs.
• Development of the Trent XWB is in full swing, costing a lot of money, too.

So one could suspect that RR is running into a cash problem. Luckily there are the Trent 700, the leading engine for the A330, and the V2500 and Airbus upping deliveries for the A320. But if these two "cash cow" programmes can save RR in the long run, if there would be a main technical problem in the Trent 900/1000 (and maybe XWB), is questionable. A fundamental technical problem, a desígn fault, could end up in the grounding of the whole Trent powered A380 fleet. Qantas grounded their fleet of six A380 immediately after the incident, Singapore would be hit heavy with eleven A380 in their fleet today, Lufthansa so far took delivery of four aircraft.

It is too early to call today’s failure a disaster for Rolls Royce (and subsequently, for Qantas, Singapore Airlines, Lufthansa and, if the worst comes to the worst, Boeing and all their B787 Trent 100 customers) – but the possibility is there…

Update: meanwhile is is obvious that an uncontaines failure happened. Pictures are showing damage to the wing - Singapore Airlines effectively grounded their fleet also. Officially, all flights are just "delayed" until the engines are inspected, but a 100% inspection of the disks for such a failure would mean to take the engine apart...

Update 2:
Just found the preliminary report of the uncontained failure in the RB211-524, which happened on August 30th. It can be found here.
The key observations are (quoted from the report):

• All of the turbine blades had separated from the IP turbine disk.

• Blades from the three LP turbine stages were either fractured through the airfoil section or separated from the disk.

• The LP stage 1 nozzle guide vanes were destroyed. The remaining LP nozzle stages were substantially damaged.

• The LP turbine bearing and adjacent phonic wheel and speed probes were destroyed.

• The IP shaft was severed towards the aft end.

This picture is obviously a part of a turbine disk that fell on the island of Batam - we will soon hear if it is also the IPT disk - at least all baldes are missing.

The Trent 1000 failure also happened in the IP Turbine. If now yesterday's failure also can be tracde back to the IPT, I would be happy not to be employed in Derby...