Leeham News and Analysis
There's more to real news than a news release.
Leeham News and Analysis
- GE testing of giant GE9X engine aims for maturity at entry into service June 30, 2025
- Bjorn’s Corner: Air Transport’s route to 2050. Part 28. June 27, 2025
- Parent agency, FAA often at odds as politics outweighs safety June 26, 2025
- Electric Flight and the Ugly Duckling June 25, 2025
- Engine makers tout “Plan A” but have “Plan B” backups in R&D June 23, 2025
Bjorn’s Corner: Sustainable Air Transport. Part 49P. eVTOL production costs. The deeper discussion.
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By Bjorn Fehrm
December 9, 2022, ©. Leeham News: This is a complementary article to Part 49, eVTOL production costs. It discusses the typical production costs of a certified eVTOL when produced in large quantities.
eVTOLs will be produced under aeronautical production certification conditions, using aeronautical grade material and system. Our production cost model predicts such costs, including learning curve effects for each material type.
Airbus Summit Showcases Sustainability Status
By Bjorn Fehrm
December 7, 2022, © Leeham News was at Airbus Summit: Airbus briefed media and influences on its Sustainability progress during briefings in Toulouse and Munich last week. Here is an update on where Airbus is with its programs.
The overall impression is of tangible progress on techno brick research and development and echo systems programs like SAF production and hydrogen supply and ground infrastructure.
At the summit, key customers like Airlines, technology partners, and leasing companies were part of the panels, giving the customer perspective and the view of the passengers.
Figure 1. The test setup of the Airbus fuel cell turboprop engine on its A380 test aircraft. Source: Airbus.
Green aviation pressure applied to banks, oil companies, too
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By Scott Hamilton
Dec. 1, 2022, © Leeham News: Pressure from environmentalists is prompting the aviation industry to move toward sustainable fuels.
But the pressure is not just on aviation. It’s also on bankers who finance airplanes and aerospace companies. These firms must show their shareholders, stakeholders and special interest groups that they are taking sustainability into account as they finance their customers.
The pressure is on oil companies, though many believe Big Oil isn’t really interested in cutting back its core business in favor of alternative energy.
In an interview with LNA, Chris Raymond, the chief sustainability officer for The Boeing Co., is frank about the challenges of meeting commercial aviation’s goal of achieving net zero carbon emissions by 2050. But he’s optimistic that the industry is on the right path.
It’s a path that’s been promoted before, with little success. In the first decade of the 21st century, the industry talked big but little activity occurred. In 2011, Jim Albaugh, then the CEO of Boeing Commercial Airplanes, predicted that 10% of fuel by 2020 would be Sustainable Aviation Fuel (SAF). The reality was that SAF accounted for 0.001% of the fuel.
Credit: Boeing.
Today, there are demonstration flights, including passenger-carrying flights, that used 50% SAF.
MTU gets support from Pratt & Whitney to develop the WET engine
By Bjorn Fehrm
November 29, 2022, © Leeham News: MTU and Pratt & Whitney presented an EU Clean Sky project today where they will develop an advanced engine concept based on the Pratt & Whitney GTF. The project is called SWITCH, an acronym for Sustainable Water-Injecting Turbofan Comprising Hybrid-Electrics.
There are participants from 11 countries in the project, among them Pratt & Whitney’s sister company Collins aerospace, GKN’s Swedish part, and Airbus.
The engine, which has a mild parallel hybrid architecture, extracts more energy from the turbofan fuel by driving the core exhaust through a vaporizer, where it recovers more heat from the core exhaust, Figure 1. Water from the exhaust, extracted from the core exhaust in a condenser, is heated to steam by the vaporizer and then drives a steam turbine that co-drives the fan. The steam is finally injected into the combustor to lower emissions.
The WET cycle will gain about 10% efficiency compared to today’s GTF. The concept also has a hybrid part which is primarily used for a low-emission taxi.
Bjorn’s Corner: Sustainable Air Transport. Part 47. eVTOL traffic
By Bjorn Fehrm
November 25, 2022, ©. Leeham News: We have gone through the flight principles for different eVTOLs, the critical systems such as battery systems and flight controls, their energy consumption/performance, and how green they are compared to other ways of getting to an airport.
This is all about the flying vehicle. But it’s only part of the system needed for this transport system to work and be safe. We now discuss the other bits needed.
Figure 1. The JFK, Newark, and Manhattan airspace. Click for a detailed view. Source: Foreflight.
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.
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Bjorn’s Corner: Sustainable Air Transport. Part 44P. eVTOL operating costs. The deeper discussion.
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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.
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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
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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.”