2/27/2014

Who needs Qantas?

Sorry for this rhethorical question!  And of course it would be bad if another iconic name in aviation history would disappear. But reading the news from "down under" today, I am coming to the conclusion that the best solution would be to drop the Qantas brand altogether and just to continue with Jetstar. To "save" the Qantas brand name Jetstar could then be renamed Qantas and join oneworld (again).
At least with the alliance with Emirates the international operations of Qantas itself became irrelevant. It looks more like a feeder for Emirates. And now that Emirates will start codesharing with the Qantas LCC offshoot Jetstar, there is no real need for a domestic Qantas. Concentrate all domestic efforts on Jetstar and act as a feeder for Emirates in markets like Singapore, Ho Chi Minh and elsewhere in south east and north asia.

Rolls Royce looking ahead...

Yesterday Rolls Royce surprised the aero engine world at a briefing about it's strategic roadmap by looking ten and more years ahead and revealing, what the company plans as their next steps in engine development.

In the 2020 timeframe we could see a further evolution of the Trent 3-spool engine family for now called "Advance" (I am sure the name will change once it should evolve from being a technology project and becomes a real program). This engine should deliver an SFC that is 5% better than the Trent XWB. As aspire aviation pointed out, the GE9X for the B777X should be about 5% better than the Trent XWB, so it is clear who is the "enemy" here.
The time frame and the SFC goal puts this engine concept  in the position to be a good candidate to power the A380neo, if the project goes ahead. But Airbus could also ask for a version with more thrust than the roughly 70klbf needed for a re-engined A380 to power a A350-1100 and then have a formidable competitor to the Boeing B777-9.
A first test engine based on the Trent XWB, but with a new core with a higher OPR - up to 60 and thus being on the same level as the GE9X - should run as early as next year.

The second engine does not necessarily build on the Trent 3-spool architecture as it - potentially - could use a gear as we currently have on the PW1000G family from Pratt&Whitney. Of course also a 3-spool GTF is possible, but I doubt that makes real sense, so I would guess it would have 2 spools. This engine should then be another 5% better than the "Advance" engine.
This engine concept should not only target the widebody market but also future narrowbodies. In the light of recent discussions about a possible B757 replacement and a successor to the B737MAX family with an EIS around 2025 this is an interesting move of course. After selling their stake in the IAE to P&W, both companies announced  a partnership for future narrowbody programs. This partnership was later canceled. But for any future narrowbody we should expect a choice of two engines, not three. And CFM seems to be the frontrunner in any case (unless the LEAP engines will fail completely, what I doubt), so either RR or P&W would be out of the game. So is this move aimed at P&W begging for a new try of the partnership? Who knows...
Anyway, the above SFC comparisons are true for widebody engines in the GE9X class - for narrowbody engines we have to scale the SFC values, as for example the tip clearances are not scaling with the physical smaller components of the engines. Relative clearances are larger and so are aerodynamic and parasitic losses. Therefore all engine components have lower efficiency levels. And as the core components (high pressure compressor and turbine) get smaller and smaller with increasing bypass ratio (BPR) and overall pressure ratio (OPR) for a given thrust, it gets harder and harder to maintain a decent efficiency level. Also surge capability of the compressor might not be easy to control. In the end, to achieve an OPR of 70(!) for this engine I predict this will only be achievable with a radial compressor stage at the back and of the compressor. And at temperatures that will be reached at such a high OPR this wheel has  to be out of a material that can only be found in turbines today. Maybe CMC? Then good luck producing such a complex piece out of that material? The other possibility would be to have an intercooler between the low and high pressure compressors. But that would add weight and complexity, counterproductive for a narrowbody engine. This is why I see that concept better suited for a long range application, where (engine) weight does not have such an immediate effect on fuel burn, The same argument could be, but must not be necessarily true for the envisioned variable pitch fan system. This idea goes back to the ADP concept from P&W from the 1980's. The variable pitch system has two great advantages versus non-pitch fans: there is no need for a thrust reverser (which save weight) and the whole nacelle can be shortened, also saving weight. On the other hand, the pitch system itself is complex and needs additional maintenance. As these maintenance cost are mainly cycle driven, I also see this technology better suited for long-range, low cycle operations.
But who knows what "white rabbits" Rolls Royce will pull out of their hat by then - it is a great company and I would not be surprised if they find ways to handle all these challenges.

2/20/2014

„Premature“ engine upgrades

In the context of my last post I wondered why MTU now starts talking about an upgraded GTF to be delivered in 2019. We are one and a half years away from EIS of the PW1100G on the A320neo and the engine is  - well – not selling bad. Why announcing an upgrade now? To enhance SFC by 3% does not sound cheap - GE and RR needed two improvement packages to bring the engines for the B787 to SFC spevc level.
Furthermore MTU COO Rainer Martens told the press that these enhancements could also be implemented into the other PW1000G family members (PW1200G/PW1700G for MRJ/E175E2 and PW1500G/PW1900G for CSeries/E190E2&E195E2). So we can be sure that all aircraft OEM’s will sooner or later ask for the upgrades, just a couple of years after EIS of their respective aircraft – remember that the E175E2 should have an EIS in 2020, AFTER the PW1100G is available with the upgrade. Sounds like all the development engineers will have secure jobs at P&W, MTU, JAEC and the other PW1000G partners for the years to come. Good for them, bad for the "bean counters" in the companies and the financial breakeven of the engine programs.
For Airbus, the revelation has probably a good and a bad side. The good side is that the A320neo will enhance the competitive position against the B737MAX (and maybe later a CS500), but also the A319neo could be in a better position against the CS300. On the other side, remaining delivery positions for the A320neo in 2018 will be not that easy to fill without giving another discount for not getting the upgrade.

2/19/2014

The B757 successor discussion

Yesterday MTU’s COO Rainer Martens revealed during the annual results presentation that there is a plan to upgrade the PW1100G engine for the A320neo with another 3% SFC jump by 2019. On a side note, as the turbo machinery of the PW1100G and the PW1400G are identical,  the MS-21 will also benefit from that as I think that P&W and their partners will not start building  two different engines.
But what does that mean in a broader context?
Firstly, we can be very sure that a similar PIP (Performance Improvement Package) will also be worked out for the LEAP-1A (and the LEAP-1C destined for the COMAC C919, as this engine has the same turbo machinery as well). Another report on a german website cites MTU’s Martens that the 3% improvement are agreed with Airbus so we expect that there is a corresponding  agreement between Airbus and CFM to lower SFC around 2019/20. As the GE9X goes into service by that time frame we can expect a lot of technology transfer from the GE9X to the LEAP-1A – and subsequently to the LEAP-1B for the B737MAX.
Secondly, this makes the business case for any A320neo and B737MAX successor harder. This is why I do not believe in a B757 successor in the time frame that was discussed by Scott Hamilton and others lately. At least not in the sense of a purpose build aircraft. Here is why:

·         The 3% lower SFC for the A321neo (and probably sooner or later also for the B737MAX-9) leads to 100+nm more range, bringing these two aircraft even closer to the capabilities of the B757 today.

·         As of today the A321ceo can do about 95% of all routes flown by the B757 today. And the A321neo can only NOT do five city pairs flown by the B757 today (I go that verbally from Airbus). 

Add the 100 extra miles coming out of the engine improvement and what is left? Maybe three routes, maybe four routes, maybe still all five. Add some improvements to the airframe and what is left then…?
I am  sure there is no business case left then for building a standalone aircraft with the capabilities of the B757. But also as part of a new family of narrowbodies, aka the A30X and the B797, there is no real need to compromise the efficiency of the whole family with a wing that is large enough to cover distances more than what the A320neo/B737MAX families will do. Otherwise Airbus and Boeing could lose market share against a Bombardier CS500 and a forthcoming Embraer small narrowbody  which are designed for ranges less than 3000nm.
But I do not see these new breeds coming a of 2025 as James N. Krebs postulated in this very interesting guest column at Leeham News. But if we see a further 3% improvement from the engines at the end of the decade, how should there be another jump of 20% in fuel burn in 2025? The technology for an aircraft with an EIS must be defined by 2018/19. With a regular tube-and-wing aircraft I cannot see a jump more than 10% from the airframe - if designed for the same range (more range: less efficiency gain for shorter routes). If we take 1% efficiency gain for every year from improved engine design (and that seems optimistic as it gets harder and harder), we get a maximum of 15% versus neo/MAX. Not taken into account that there can still be something done to the existing aircraft as well like building the fuselage from AlLi or enhancing the wing. The business case for an all new aircraft then disappears in my eyes. But I am not a bean counter…err… accountant.
Another question is if someone will do something in the sector left by the likes of the A300-600R and the B767-300(non ER): 250-300 seats, 4000nm max range. Being hinted to think about that, as can be read in the Pudget Sound article. I do not count that as a B757 successor and  I do not know if there is a business case for that but Lufthansa always cried for “people mover” like that.