Leeham News and Analysis
There's more to real news than a news release.
Leeham News and Analysis
- RTX Q1 2025 Earnings: GTF Talk Takes A Back Seat To Tariffs April 22, 2025
- Tariffs Tumult Takes Over GE Aerospace Q1 2025 Earnings Call April 22, 2025
- Boeing reports mixed results of latest employee survey, but middle management and officers remain key obstacles April 22, 2025
- Hopes for 1Q financial progress turns into bumpy ride for Boeing April 21, 2025
- Bjorn’s Corner: Air Transport’s route to 2050. Part 18. April 18, 2025
Bjorn’s Corner: Efficient systems
By Bjorn Fehrm
05 February 2016, © Leeham Co: In recent Corners, we looked into technologies which have made the new breed of airliners more efficient.
We’ve talked about how new engines can raise efficiency by about 15% and how aerodynamic improvements, like more efficient split winglets, can add another 1%-2% over single blade winglets. We have also looked into modern ways to manufacture the more resilient and lighter composites structures that designers want to use to increase aircraft efficiency.
There is one area which we have not covered: the aircraft’s systems and how these can be made more efficient. An improved system architecture can add the efficiency improvement of a split winglet. So let’s have a look at the trends in aircraft systems.
We start this week with power distribution.
Bjorn’s Corner: Exciting 2016
By Bjorn Fehrm
29 January 2016, ©. Leeham Co: In the corner of two weeks ago we did a retrospective of 2015. Time for looking ahead. The year of 2016 will be quite interesting. We had entry into service of the first re-engine single aisle aircraft this week, the Airbus A320neo, the same week as we expect first flight from its main competitor, Boeing’s 737 MAX 8. We will also see first flight of the Embraer E190E2 and A350-1000 before the year is over.
The Mitsubishi MRJ shall go test flying in earnest and Bombardier’s CSeries 100 and 300 shall enter service. On top of that, the COMAC 919 will probably start ground roll tests this year and we should see roll out of Irkut’s MC-21. I would say 2016 is a busy year for civil aviation.
In the 2015 corner we talked a lot about engine technology as a key driver to further efficiency of air transportation. Now will dissect the airframe technology that all these new projects will bring us. Read more
Bjorn’s Corner: The coin has two sides
By Bjorn Fehrm
22 January 2016, ©. Leeham Co: Today’s Corner should have been about something else. But we learned yesterday that yet another order did not go Bombardier’s way, the 125 seat aircraft order of 40 units for United Airlines.
Normally I don’t care about who gets a single aisle order; the players that are active are all producing very good products and which one that gets chosen in not a big deal.
Boeing took this business with its smallest 737NG member 737-700. The 737NG was scheduled to take on aircraft like the CSeries and the re-engined A320neo while Boeing perfected a clean sheet single aisle for the end of this decade.
This corner is about national characters and what happens when this character gets under pressure. It’s also about the fact that the coin has two sides.
Bjorn’s Corner: What did we learn in 2015; engines
By Bjorn Fehrm
15 January 2016, ©. Leeham Co: Last week we looked back on what happened in 2015 on the airframe front. We finish the retrospective by looking at what turbofan engine technology came to market in 2015. New engine technology is vital, as it is on the engine side that the quest for higher fuel efficiency has the largest successes.
While advances on the airframe side might bring an additional 5% per generation, the engines typically increase their efficiency per new generation with up to three times that value. Fuel efficiency per delivered thrust unit was improved with a whopping 15% over the engine it replaces for the Pratt & Whitney Geared Turbofan (PW GTF). It was certified for use on the Airbus A320neo in Q4 2015
The competing CFM LEAP-1A shall deliver the same improvement level to the A320neo once it is certified in the summer of this year. This engine has a smaller sister that started ground tests last year, the LEAP-1B, which is developed for the Boeing 737 MAX series.
The engine that is easily forgotten is the Rolls Royce Trent XWB. It entered service on the Airbus A350-900 during the year. It brings an improvement level of around 10% compared to the engines of the aircraft that the A350 replaces (Airbus A340/A330ceo and Boeing’s 777-200 range).
Bjorn’s Corner: What did we learn in 2015?
By Bjorn Fehrm
08 January 2016, ©. Leeham Co: It’s the first Corner for the year and a look at 2015 as a year of technology advancements is due. 2015 will be remembered as the year when three clean sheet airliners passed important milestones. This will not happen for many years to come, so it will be worth to look at what they brought to world of aviation.
I’m thinking of Bombardier’s (BBD) CSeries getting certification for its first variant; the Mitsubishi MRJ doing its first flight’ and COMAC’s C919 being rolled out. Going forward, we will only have derivatives progressing through such milestones for years except for the roll-out of United Aircraft’s MS-21 single aisle airliner in 2016.
The Airbus A320neo was certified in 2015 and Boeing’s 737 MAX rolled out, but these are derivatives of in-service aircraft.
Embraer’s E-Jet E2 will roll out in February but this is a further development of today’s E-jet and Airbus A350-1000 is a variant of the in-service A350-900.
It will be a long time before we see so much new in a year, so it can be instructive to look at to what extent did these new aircraft bring the state of the art of airliners forward.
Bjorn’s Corner: Engine efficiency revisited
By Bjorn Fehrm
18 December 2015, © Leeham Co:Part of the discussion following last week’s article around quad or twin engine airliner designs was about engine efficiency and specifically around the engine’s thermal efficiency as a function of Pressure Ratio, PR.
I got the question, if an engine working at a higher pressure ratio was therefore working at a higher thermal efficiency. I knew enough on the subject to know I did not have a good answer without doing a bit of checking; jet engines are no simple contraptions.
I have previously written about turbofan efficiency in a Corner. The article was focused around propulsive efficiency. Now we will have a look at the other part of overall engine efficiency, the thermal efficiency or the efficiency of the core.
Bjorn’s Corner: Twins or quads?
By Bjorn Fehrm
11 December 2015, ©. Leeham Co: The debate over two or four engines for long range aircraft is as old as the jet airliner. A number of myths have been pedaled over the years over the virtues of the one over the other. The myths have even been presented by airline CEOs as “facts that are known in the industry.”
Having done several in-depth comparisons of two-vs-four engined long range aircraft, we can’t find the patterns that these myths propel: that a quad is less efficient than a twin and should have higher maintenance costs. What we see is that it is all dependent on what one compares and to what technology generation the one or the other aircraft belong.
When we didn’t get the same results as the myths on a number of areas, we started to wonder what could have created the myths in the first place. Looking at what four engined airliners could have been the source of the rumours, we started to see a pattern. It was a pattern of apple-and-oranges being compared and wide ranging conclusions being drawn.
Here is what we found. Read more
Bjorn’s Corner: Modern IFE
By Bjorn Fehrm
04 December 2015, ©. Leeham Co: During the last two weeks I have been busy explaining how a mid-life long range aircraft is refurbished. The articles have been about how to prepare 10 year old Boeing 777-200ER and Airbus A340-300 for their second half of life.
One of the things that must be done is updating the part of the aircraft that meets the customer, the cabin. Most passengers don’t know much about the aircraft they are flying, but they can tell you if the seats were comfortable, if there was enough leg space and if the movies on the entertainment system were any good.
This means that if the cabin is brought up to a modern standard with lie-flat business seats, refreshed interior surfaces and textiles, and if there is a personal IFE unit with good content, the passenger will not reflect over that he flies an old aircraft.
Such refreshes cost a lot of money. Without changing all items in a 300 seat cabin, one is easily at between $5m-$10m for material and installation. One of the problems when wishing to keep existing seats, for economic reasons, is that it is virtually impossible to implement in-seat IFE to an existing seat. Luckily there are other solutions. Read more
Bjorn’s Corner: Aircraft deterioration
By Bjorn Fehrm
27 November 2015, ©. Leeham Co: In an article yesterday, we looked at the economics of acquiring used aircraft for long range operations. We compare getting a second hand Boeing 777-200ER or Airbus A340-300 to operate as a long range complement to an existing network or to start a charter operation to destinations further away than previously possible.
The low fuel cost has made longer range destinations economical for a number of business models and the low capital cost and good conditions of these aircraft open new opportunities.
One of the things that must be considered in such analysis is the deterioration of the aircraft’s components. This will affect the aircraft’s performance in a marked way. In fact, an aircraft only has its factory advertised performance once in its life-time: at delivery.
Certain types of deterioration can be reset to zero by maintenance actions; others will not be reset completely by a visit to the maintenance shop. Let’s go through the different forms of deterioration that one normally caters for in performance calculations and how one go about to restore the aircraft’s operation as much as possible with scheduled maintenance.
Bjorn’s Corner: Production rates
By Bjorn Fehrm
20 November 2015, ©. Leeham Co: Emirates Airline CEO, Tim Clark, is quoted as having said “it takes them forever to get this thing up.” He was talking about the Airbus A350 production rate and his reasons for delaying Emirates’ decision on what to buy for the airlines medium range needs. Clark said Emirates wants more aircraft in operational use before they can evaluate the operational characteristics of the A350.
Emirates want to see at least 20 aircraft in operation and right now it is about seven to nine that fly every day. Actual deliveries stand at 10 with one month to go before the first anniversary when deliveries started (the first A350-900 was delivered to Qatar Airways on the 22 December 2014).
Looking at how many aircraft that are actually flying, one can agree with him. It seems actual production rate is more like one per month rather than the three to four a month that Airbus talked about at the first delivery ceremony.
So why is this? Is the production of A350 therefore in serious trouble? What is taking them so long? Has Emirates pointed to a weak part of the A350 program?