Leeham News and Analysis
There's more to real news than a news release.
Leeham News and Analysis
- Boeing CEO promises company is turning around…again April 24, 2024
- Solid start for stand-alone GE Aerospace despite cuts to LEAP output April 23, 2024
- SPEEA, Boeing at impasse over safety program, union says April 23, 2024
- Better transparency needed on Boeing’s 1Q earnings call April 22, 2024
- Bjorn’s Corner: New engine development. Part 4. Propulsive efficiency April 19, 2024
The range of the Airbus A321XLR, Part 2
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By Bjorn Fehrm
September 7, 2023, © Leeham News: The advertised range of 4,700nm for the Airbus A321XLR enables true trans-Atlantic single-aisle routes that can originate further inland, both in the US and Europe. When EASA and FAA demanded that Airbus add extra fire protection around the tank that gives the extended range, rumors told of a substantial range loss.
Last week we could see that whatever the weight increase, the range loss is not substantial. Now we look at what Airbus could do to restore the range of the A321XLR.
Figure 1. The Airbus A321XLR. Source: Airbus.
Summary:
- We could see last week that the range shortfall from the rumored weight increases is less than rumored.
- When we look at the fixes for any range shortfall, they seem straightforward and doable.
Bjorn’s Corner: New aircraft technologies. Part 28. Alternative Preliminary design
By Bjorn Fehrm
September 1, 2023, ©. Leeham News: We described the Preliminary design phase of an airliner development program last week. One could say this was the classical way that aircraft projects conduct Preliminary design.
There is a different way that Conceptual and Preliminary design can be run. It’s more along the lines of pre-development of functions, as a reader commented on two articles back.
Figure 1. An alternative new airliner family development plan. Source: Leeham Co.
Bjorn’s Corner: New aircraft technologies. Part 26. Preliminary design
By Bjorn Fehrm
August 25, 2023, ©. Leeham News: We described the different phases of an airliner development program last week.
We will look at the Preliminary design phase this week, what work is done, the tools used, and how it can be made more efficient.
Figure 1. A typical new airliner family development plan. Source: Leeham Co..
The reality behind the eVTOL industry’s hyperbole, Part 7.
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By Bjorn Fehrm
August 24, 2023, © Leeham News: We have looked at the promises the VTOL industry made in their Investor prospects and what the reality is as the VTOLs come closer to Certification and production.
We started by using Joby and Archer as examples; now, we wrap the series by looking at some other top VTOL OEMs and how their claims have changed as the projects come closer to reality.
Figure 1. The Lilium jet VTOL. Source: Lilium.
Summary:
- Joby Aviation and Archer are not alone in backpedaling on promised performance as certification nears; other OEMs that are investor-financed have the same problem.
- In summary, the VTOLs in the first generation can only fly short-range missions. Longer flights run into energy reserve and cost problems.
The reality behind the eVTOL industry’s hyperbole, Part 6.
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By Bjorn Fehrm
August 17, 2023, © Leeham News: We look at the promises that the VTOL industry has made in their Investor prospects and what the reality is as they come closer to Certification and production.
We used our Aircraft Performance and Cost model to understand the data for the typical missions for the Joby S4 and Archer Midnight VTOLs and how the economics pans out for these missions. We now look at the results and compare them to what’s been projected from the OEMs.
Figure 1. The Joby S4 VTOL. Source: Leeham Co.
Summary:
- We found the VTOL OEM’s economics for the typical 10-minute shuttle flights optimistic.
- When we go back and look at investor deck projections, the cost comparison to helicopter costs were totally off the mark. When we correct this the VTOL is more expensive to operate then an equivalent helicopter.
Bjorn’s Corner: New aircraft technologies. Part 25. Efficient development
August 11, 2023, ©. Leeham News: We have described a number of technological advances that can be used to make the next-generation airliners more efficient and, thus, more environmentally friendly.
Part of developing more efficient next-generation aircraft is to change the development process to be more efficient. The last Boeing aircraft, the 787, took 7.5 years from launch to entry into service, and Airbus A350 took 8.5 years.
The target is to reduce this by up to 50%, but how?
Figure 1. The Airbus A350 development schedule. Source: Airbus.
Bjorn’s Corner: New aircraft technologies. Part 24. Single or dual aisle fuselage?
By Bjorn Fehrm.
August 4, 2023, ©. Leeham News: This is a summary article to Part 24P. Single or dual aisle fuselage. It summarizes the drag and weight simulations we have done on fuselages for the next generation Heart of the Market airliners. When it comes to drag and weight for a 250-seat airliner that shall replace today’s Single Aisle, is a Single Aisle fuselage lower in drag and weight than a Dual Aisle fuselage?
Figure 1. The drag components of a Single Aisle airliner at 35kft and M0.78. Source; Leeham Co.
The reality behind the eVTOL industry’s hyperbole, Part 4.
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By Bjorn Fehrm
August 3, 2023, © Leeham News: We look at the promises that the VTOL industry has made in their Investor prospects and the reality as they come closer to Certification and Production.
After looking at claims of range and utility, we now look at the operating economics. To do that, we need to predict the net sales price of these machines. We use our Aircraft Performance and Cost Model (APCM) to predict the production cost over time and, thus, the needed net sale price of the VTOLs.
Figure 1. The Archer Aviation Midnight VTOL mockup at the Paris Air show. Source: Leeham Co.
Summary:
- The VTOLs are big; the Archer Midnight is the size of a nine-seater commuter aircraft (Figure 1). Aircraft costs are related to size and weight.
- VTOLs use aeronautical production methods and supply chains for parts and systems. The production costs are, therefore, predictable.
Bjorn’s Corner: New aircraft technologies. Part 23. Efficient flight speeds
By Bjorn Fehrm
July 28, 2023, ©. Leeham News: We touched on efficient flight speeds in Part 21, but it was focused on fuel efficiency and how new technologies require the airliner to fly at new altitude-speed combinations to maximise the fuel efficiency gains.
We now look at how to fly the airliner cost-efficiently, which is slightly different from how to fly it fuel efficiently.
Figure 1. The difference between lowest fuel burn speed (Mmr) and long-range cruise speed Mlrc. Source: Airbus.