Bjorn’s Corner: Sustainable Air Transport. Part 58. Summary Part 2.

By Bjorn Fehrm

February 17, 2023, ©. Leeham News: Last week, we summarized that SAF is the short-term solution for GreenHouse Gas (GHG) reduction for Air Transport, and hydrogen is the longer-term solution for up to medium-haul flights.

What about battery and hybrid aircraft? It’s the go-to solution for ground transport (except for long-haul trucks, which are going hydrogen, Figure 1)?

Figure 1. Mercedes hydrogen truck from the world’s largest truck maker. Source: Daimler trucks.

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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.

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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.

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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.

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Bjorn’s Corner: Sustainable Air Transport. Part 25. High Temperature Fuel Cell-based 70-seat airliner

By Bjorn Fehrm

June 24, 2022, ©. Leeham News: Last week, we discussed how a High Temperature Fuel Cell (HTFC) could improve the installation of a propulsion system in our 70-seat airliner. We now add this variant to the systems we examined for installation effects and efficiencies.

The deeper discussion is in the sister article, Part 25P. High Temperature Fuel Cell-based 70-seat airliner.

Figure 1. The ATR 72-600 70-seater turboprop. Source: ATR.

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Bjorn’s Corner: Sustainable Air Transport. Part 25P. High Temperature Fuel Cell-based 70-seat airliner. The deeper discussion.

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June 24, 2022, ©. Leeham News: This is a complementary article to Part 25, High Temperature Fuel Cell-based 70-seat airliner. It adds the masses and efficiencies of a High Temperature Fuel Cell system to our 70-seat airliner fuel cell variants.

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Bjorn’s Corner: Sustainable Air Transport. Part 23. Fuel Cell-based 70 seat airliner

June 10, 2022, ©. Leeham News: Last week, we looked at the different fuel cell systems that can go into a 70-seat airliner like the ATR 72. In this week’s Corners, we implement these in the aircraft and look at installation effects and efficiencies.

The deeper discussion is in the sister article, Part 23P. Fuel Cell-based 70-seat airliner.

Figure 1. The ATR 72-600 70-seater turboprop. Source: ATR.

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Bjorn’s Corner: Sustainable Air Transport. Part 22P. Fuel Cell system efficiency and mass. The deeper discussion.

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June 3, 2022, ©. Leeham News: This is a complementary article to Part 22, Fuel Cell system efficiency and mass. It analyses the power, loss, mass, and efficiency consequences of the different fuel cell architectures described in the main article.

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Bjorn’s Corner: Sustainable Air Transport. Part 18. Advanced Hydrogen Gas Turbines

By Bjorn Fehrm

May 6, 2022, ©. Leeham News: Last week, we looked at how we create the shaft power for the thrust device we discussed before. We described the basics of a hydrogen-burning gas turbine alternative.

When we have liquid hydrogen as fuel, several advanced developments are possible. It’s what we look at now.

Figure 1. Airbus ZEROe hydrogen gas turbine concepts. Source: Airbus.

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Bjorn’s Corner: Sustainable Air Transport. Part 17. Gas Turbine Propulsion

By Bjorn Fehrm

April 29, 2022, ©. Leeham News: Last week, we looked at the thrust generating device that aircraft propulsion systems use. We could conclude that independent of how we create the shaft power, we can choose different thrust technologies with desired characteristics. A propeller, open fan, or fan in nacelle covers different speed ranges and efficiency profiles.

Now we look at how we generate the shaft power for these devices. We start with the hydrogen-burning gas turbine alternative.

Figure 1. Airbus ZEROe hydrogen gas turbine turboprop concept. Source: Airbus.

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