Leeham News and Analysis
There's more to real news than a news release.
Leeham News and Analysis
- 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
- Boeing unlikely to meet FAA’s 90-day deadline for new safety program April 18, 2024
Bjorn’s Corner: New aircraft technologies. Part 6P. Fuselage manufacturing
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By Bjorn Fehrm
March 31, 2023, ©. Leeham News: This is a complementary article to Part 6. Fuselage manufacturing. It discusses in detail how to manufacture a non-circular fuselage that avoids fatigue problems.
Bjorn’s Corner: New aircraft technologies. Part 4. Fuselage trades
By Bjorn Fehrm
March 17, 2023, ©. Leeham News: This is a summary of the article New aircraft technologies. Part 4P. Fuselage trades. In the article, we discuss the trade-offs involved in designing a fuselage of an airliner with 250 seats using different architectures.
We examine what parameters decide the performance of an aircraft and how fuselage changes like single aisle versus dual aisle affect these parameters.
Figure 1. induced drag comes from the global air circulation from the bottom to the top of the aircraft. Source: Leeham Co.
Bjorn’s Corner: New aircraft technologies. Part 3P. Airframe improvements
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By Bjorn Fehrm
March 10, 2023, ©. Leeham News: This is a complementary article to New aircraft technologies. Part 3. Airframe improvements. It discusses in detail the areas of an airliner airframe where tangible improvement can be made to make it more efficient and thus lower cost combined with less Green-House-Gas (GHG) emissions.
Bjorn’s Corner: New aircraft technologies. Part 2. Target markets.
March 3, 2023, ©. Leeham News: We started a series last week that will look at what environmental and air traffic economy improvements we can get with traditional aeronautical technology developments.
Before we look at technology, we must define what air transport market has the highest impact from changes. Useful technology developments are not necessarily the same for Regional, Narrowbody, or Widebody aircraft.
Figure 1. The distribution of Available-Seat-Kilometer by airplane type 2019. Source: JADC.
Bjorn’s Corner: Aircraft technology developments. Part 1.
By Bjorn Fehrm
February 24, 2023, ©. Leeham News: In the Sustainable Air Transport series we finished last week, we described new aircraft technologies developed to reduce Green House Gas (GHG) emissions.
There was one area we didn’t discuss, the progress on conventional technologies to reduce the fuel burn of an airliner.
We now start a series, digging deeper into what we can do with conventional technologies to reduce the fuel burned per passenger kilometer and, thus, GHG emissions.
Figure 1. Truss braced wing, a way to reduce aircraft drag. Source: Boeing.
The Airbus A220-500, a deep-dive analysis, Part 2
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By Bjorn Fehrm
Jan. 23, 2023, © Leeham News: Following Thursday’s article about an up-and-coming Airbus A220-500, we now look at the operational cost for the A220-500 and compare it with the A320neo it should replace.
We put the data we discussed in Thursday’s article in our Aircraft Performance and Cost model, fly the aircraft on a typical single-aisle mission and look at the results.
Figure 1. A rendering of an A220-500 that takes 157 passengers. Source; Leeham Co.
Summary:
- The A220-500 would be a viable replacement for an A320neo.
- With the changes/improvements we discussed, it beats the A320neo on operational costs. The differences are not of the speculated level, however.
2023 outlook for Sustainable Aviation
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By Bjorn Fehrm
Jan. 16, 2023, © Leeham News: In the years from 2015, Sustainable Aviation awareness has grown from “something interesting, but will it be needed?” to “how do we fix the environmental issues we have fast enough.” Scientists saw what happened 20 years ago, but the general public didn’t react until it affected everyday life.
The development of more Sustainable Aviation solutions has taken a similar route. Until 2015 the changes to morph aviation into a more sustainable path were a scientific discussion. At Le Bourget Air Show 2015, Airbus presented the E-Fan (Figure 1) that would cross the English Channel the following month. It started an intense debate about sustainable propulsion concepts for aircraft.
Eight years later, where are we today, and what will happen in 2023?
Figure 1. Airbus E-Fan at the 2015 Le Bourget Air Show. Source: Wikipedia.
Summary:
- The year will witness the “separation of the wheat from the chaff.” Viable concepts will prove themselves, and thin concepts, technically or funding-wise, will fail.
- We have a number of first flights from interesting projects. Several are in the “wheat” category.
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.
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 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.