Leeham News and Analysis
There's more to real news than a news release.
Leeham News and Analysis
- Boeing IAM vote in 2 days; approval a hard sell September 10, 2024
- Union scourge Frank Lorenzo at last tells his story in “Flying for Peanuts” September 10, 2024
- Slow production ramp up, international sanctions slow C919 progress September 9, 2024
- Boeing, IAM reach tentative agreement on new contract September 8, 2024
- Bjorn’s Corner: New engine development. Part 23. Development risks. September 6, 2024
Bjorn’s Corner: Sustainable Air Transport. Part 52. What can be done before 2050?
By Bjorn Fehrm
January 6, 2023, ©. Leeham News: Since we started this series about our Air Transports and their pollution, we have covered different schemes of reduction such as improved Air Traffic Control (ATC), change to electric aircraft (battery/hybrids) or hydrogen as fuel, and lastly, eVTOLs.
Of these changes, only ATC can have a short-term effect, but it’s a slow mover for organizational reasons.
Changes to how our aircraft are propelled are, unfortunately, longer-term improvements, as we see in an example below.
But we need fast change. We’ve had the craziest of summer and now winter in Europe, where I live, and it’s not a one-time variation. And this is not confined to Europe; the weather change is faster than we thought, and it’s worldwide.
So what can we do?
Figure 1. CO2 emissions by region. Source: Our World in Data.
Bjorn’s Corner: Sustainable Air Transport. Part 51. eVTOL wrap.
By Bjorn Fehrm
December 23, 2022, ©. Leeham News: After 25 articles about the eVTOL, it’s time for a wrap. We have looked at most aspects of this new form of air transportation, including how sustainable it is.
Today we summarize what we found before we go on to the next subject in Sustainable Air Transport.
Figure 1. The series started with a picture of the eVTOL that leads the trend, Joby Aviation’s S4. Source: Joby Aviation.
Universal Hydrogen’s ATR72 Project
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By Bjorn Fehrm
Dec. 22, 2022, © Leeham News: Last week, we wrote about Universal Hydrogen’s (UH2) plans to fly a hydrogen-fueled demonstrator aircraft in early 2023, followed by a certified conversion kit for an ATR72 airliner mid-decade.
The plans for the ATR72 hydrogen conversion are at an advanced state. As the first publication, we can describe the overall design and the technical details. The ATR72 implementation brings improvements in several areas compared with what’s been revealed before.
Figure 1. Hydrogen tank modules are loaded onto an ATR 72 using standard freight handling equipment. Source: Universal Hydrogen.
Summary:
- The target ATR72 conversion improves hydrogen capacity and handling compared to earlier concepts.
- The influence on the ATR seating capacity is reduced due to more efficient packaging on the aircraft.
Bjorn’s Corner: Sustainable Air Transport. Part 50. eVTOL production volumes.
By Bjorn Fehrm
December 16, 2022, ©. Leeham News: Last week, we looked at the production costs of our typical eVTOL. We could see that it was far higher than Joby’s assumption of $1.3m for the S4, about three times higher for units above 500 and even higher for earlier units.
Let’s examine where such cost numbers come from. It’s about production ramp hockey sticks and numbers never seen before. Are these credible?
Figure 1. The Vertical Aerospace VX4 in an early rendering with similar looks to the eVTOL we discuss. Source: Vertical Aerospace.
Universal Hydrogen could be first with Hydrogen Airliner
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By Scott Hamilton and Bjorn Fehrm
Dec. 15, 2022, © Leeham News: Universal Hydrogen (UH2) is perhaps weeks away from its first flight of a demonstrator that equips a De Havilland Canada Dash 8-300 with tanks of hydrogen and a fuel cell electric propulsion unit. The project shall prove the feasibility of hydrogen-fueled airliners.
The first flight’s date hasn’t been firmly set, but officials at UH2 told LNA it should be soon. Taxi tests of the aircraft will begin in the coming weeks. The flight will occur at Moses Lake in Central Washington State.
Universal Hydrogen supplies its hydrogen to the aircraft in prefilled barrel-sized tanks, called capsules, to avoid the lengthy and costly investment in storing and filling infrastructure at airports. The proof of concept is with a Dash 8, followed by a complete hydrogen conversion kit for an ATR-72 turboprop airliner.
Figure 1. Hydrogen tank pallets are loaded onto an ATR 72 by standard cargo loaders. Source: Universal Hydrogen.
Summary:
- The core business of Universal Hydrogen is the prefilled hydrogen tanks that load onto the aircraft in pallets.
- Universal Hydrogen builds the complete hydrogen fuel and propulsion system to prove and bootstrap the concept of hydrogen airliners.
Bjorn’s Corner: Sustainable Air Transport. Part 49. eVTOL production costs.
By Bjorn Fehrm
December 9, 2022, ©. Leeham News: This is a summary of the article Part 49P, eVTOL production costs. It discusses the production costs of our typical eVTOL (Figure 1) and its drain on the OEM’s finances.
New aircraft projects chronically underestimate the production cost of their certified products. One factor is the effect of the learning curves on the cost items.
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 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.
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.