Leeham News and Analysis
There's more to real news than a news release.
Leeham News and Analysis
- Bjorn’s Corner: Air Transport’s route to 2050. Part 24. May 30, 2025
- Does an A220-500 need a new wing and engines? Part 3. May 29, 2025
- Boeing’s future depends on FAA approvals May 26, 2025
- Updated, May 29, 2025: Department of Justice, Boeing OK to Non-Prosecution Agreement May 23, 2025
- Bjorn’s Corner: Air Transport’s route to 2050. Part 23. May 23, 2025
Bjorn’s Corner: Sustainable Air Transport. Part 46. eVTOL comparison with helicopter
By Bjorn Fehrm
November 18, 2022, ©. Leeham News: In the comments to last week’s Corner, there were requests for a comparison with a helicopter re. Sustainability (kWh/km). Here you go.
I also threw in a cost of operations discussion, as the helicopter is the present alternative to an eVTOL for city-to-airport air transports.
Figure 1. The Robinson R66 five-seat helicopter. Source: Wikipedia.
Read more
Bjorn’s Corner: Sustainable Air Transport. Part 44P. eVTOL operating costs. The deeper discussion.
Subscription required
By Bjorn Fehrm
November 4, 2022, ©. Leeham News: This is a complementary article to Part 44, eVTOL operating costs. It discusses the typical operating costs we can expect from an eVTOL when used in an air taxi operation.
Despite the operation of such transports being years off, an eVTOL has dominant cost factors that can be estimated today.
Bjorn’s Corner: Sustainable Air Transport. Part 42. eVTOL range.
By Bjorn Fehrm.
October 21, 2022, ©. Leeham News: This is a summary of the article Part 42P, eVTOL range. It discusses the range of a typical eVTOL flying a feeder mission from a city center to an airport.
The 42P article details the energy consumption for each stage in the mission and the range we fly. We summarize the results here.
Figure 1. The Vertical Aerospace VX4 in an early rendering with similar looks to the eVTOL we discuss. Source: Vertical Aerospace.
Bjorn’s Corner: Sustainable Air Transport. Part 42P. eVTOL mission range. The deeper discussion.
Subscription required
October 21, 2022, ©. Leeham News: This is a complementary article to Part 42, eVTOL mission range. It discusses the typical maximum range we can expect from a certified eVTOL by mid-decade.
We have described the vehicle and the mission data in the three previous Corners; now, we analyze the energy consumption for the mission and discuss the range we can achieve.
Achieving net zero carbon is a promise you can keep: P&W’s Webb
Subscription Required
By Scott Hamilton
Sept. 26, 2022, © Leeham News: The International Civil Aviation Organization (ICAO) is nearing the next step in support of dramatically cutting emissions by airlines and the aviation industry.
Graham Webb
“ICAO has been working for about the last three years on something called a long-term aspirational goal (L-TAG). That’s regarding a study that was conducted by a number of their scientists to determine if it is feasible for the aviation industry to reduce its carbon emissions specifically, to achieve a net zero standard. That’s what for a long-term aspirational goal is,” said Graham Webb, Chief Sustainability Officer for Pratt & Whitney. “At this point, the study has been completed and has been reviewed by 93 member states. It would appear that the initial motion of the language that is going to be put forward will pass.”
ICAO previously adopted the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA). L-TAG is the next step, Webb said in an interview this month with LNA.
“Once that is in place, it will enable ICAO, much as it already is done with CORSIA, to establish policies that would then be enforced by all its member states in a common, in a related way as opposed to the concern that many people have had, where you would see a patchwork. You would see some countries, such as the United States, providing incentives through vendors’ tax credits. You would see Europe in the form of mandates and taxes. They have this Emissions Trading Scheme that they’ve been putting forward and running through the Parliament. The overall objective is to have this singular global aviation industry, regulatory body, ICAO, that would then set the guidelines for the industry.”
Bjorn’s Corner: Sustainable Air Transport. Part 36. Battery Management.
By Bjorn Fehrm
September 9, 2022, ©. Leeham News: Over the last weeks, we have discussed the cells that make up the battery system for an eVTOL.
The battery system has 10,000 cells or more. All these must, on an individual level, be managed to ensure they operate inside their allowed values. The Battery Management System, BMS, has this responsibility. It’s one of the most critical safety systems in an eVTOL.
Figure 1. The Battery Management System and battery packs from EP Systems. Source: EP Systems.
Bjorn’s Corner: Sustainable Air Transport. Part 33P. eVTOL batteries. The deeper discussion.
Subscription required
August 19, 2022, ©. Leeham News: This is a complementary article to Part 33, eVTOL batteries. It discusses the trickiest system on an eVTOL, the battery system.
While Lithium Ion batteries have come a long way since the electric flight ideas took off in 2015, the battery system is still the biggest challenge for eVTOL designers, not only for total energy content but for a range of parameters.
Bjorn’s Corner: Sustainable Air Transport. Part 33. eVTOL batteries.
August 19, 2022, ©. Leeham News: This is a summary of article Part 33P, eVTOL batteries. This article discusses the trickiest system on an eVTOL, the battery system.
The battery system supplies the energy to the VTOL, and given today’s and tomorrow’s battery technology; it’s a tight resource that needs a lot of pampering.
Figure 1. We use graphs in the Pipistrel spare parts catalog to show the battery system of the Pipistrel Velis Electro. Source: Pipistrel and Leeham Co.
Airbus prepares contrail flight tests
July 21, 2022, © Leeham News at Farnborough Air Show: Airbus is converting two Arcus high-altitude gliders to check if the contrails produced by hydrogen combustion engines create an environmental problem.
The background is that experts can’t agree if the water vapor produced by hydrogen combustion (which merges hydrogen with oxygen to water) can cause global warming or not. The only way to resolve the dispute and gain fundamental knowledge is to fly and measure.
Figure 1. First flight with the Blue Condor program’s test aircraft. Source: Airbus.
Bjorn’s Corner: Sustainable Air Transport. Part 28. Vectored thrust VTOLs.
By Bjorn Fehrm
July 15, 2022, ©. Leeham News: We started the analysis of the market’s most prominent VTOLs with multicopters last week. Now we continue with vectored thrust VTOLs.
The most known exponent for vectored thrust VTOLs is Joby Aviation’s Joby S4 VTOL, Figure 1.
Figure 1. Joby S4. Source: Joby Aviation.