Leeham News and Analysis
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Bjorn’s Corner: Sustainable Air Transport. Part 4P. Reality checks, the deeper discussion.
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By Bjorn Fehrm
January 28, 2022, ©. Leeham News: This is a complementary article to the Part 4. Reality Checks article. It uses data from Leeham Company’s Aircraft Performance Model to develop the relationship between OEW (Operational Empty Weight) and MZFW (Maximum Zero Fuel Weight) compared with MTOW (Maximum Take-Off Weight) for 74 airliners in the model.
The article also discusses in more detail what’s the reasons behind large weight misses for new projects and how it’s handled.
Bjorn’s Corner: Sustainable Air Transport. Part 3. Low hanging fruit.
By Bjorn Fehrm
January 21, 2021, ©. Leeham News: Whatever is done in terms of new Sustainable technology for the aircraft, will have a limited influence on the amount of Greenhouse gases that Air Transport emits before 2050.
We will only get the new aircraft types into operation about 15 years before the deadline and with, on average, 100 to 200 aircraft per year. That’s 1,500 to 3,000 of the total of 25,000 aircraft that operate in our skies daily. It will not reduce our Greenhouse gas emissions significantly.
Sustainable Aviation Fuel, SAF, will help, but only when it’s available in quantity and to a reasonable cost. We can do things that have a much faster effect, and that’s how we manage our flights.
Figure 1. The US flights as seen on Flightradar24 yesterday. Source: Flightradar24.
Bjorn’s Corner: Sustainable Air Transport. Part 2. The problem to solve?
By Bjorn Fehrm
January 14, 2021, ©. Leeham News: Before we dig into the different alternatives we have for more Sustainable Air Transport, let’s look at the problem and its sources.
Figure 1 shows the emissions of CO2 per person since 1900 and the rise of the world temperature. The increase in world temperature changes the weather, with increased weather-related emergencies in recent years.
Figure 1. The increase in CO2 emission per capita and the rise of the world temperature from 1900 to 2018. Source: Wikipedia.
Bjorn’s Corner: Sustainable Air Transport. Part 1. A deeper look.
By Bjorn Fehrm
January 7, 2022, ©. Leeham News: We finished a 34 article series before Christmas about the enormous work involved to get a new aircraft certified for passenger transport.
It was a background article series to the one we start now, a deeper series on what’s involved in designing air transport vehicles that are less polluting for our environment. We have seen a landslide of such projects in the last years, and from an experienced aircraft designer’s desk, most of these are doomed for failure.
Figure 1. The Embraer Energia concept aircraft. A credible Sustainable Air Transport research program. Source: Embraer.
Bjorn’s Corner: The challenges of airliner development. Part 34. Wrap-up.
By Bjorn Fehrm, Henry Tam, and Andrew Telesca.
December 17, 2021, ©. Leeham News: As we wrap up the series where we look at the monumental work you have to do to get a new aircraft type certified, we will discuss how we need several aircraft variants, addressing different markets, if we shall survive as an aircraft manufacturer.
All successful aircraft manufacturers produce and market a family of aircraft. If you stay with only one variant, you will find it hard to keep good people as the development work ends.
Figure 1. Beech 1900, a 19 seater aircraft developed from the Super King Air 200 with 9 seats. Source: Textron Aviation.
Bjorn’s Corner: The challenges of airliner development. Part 33. Multi-country Certification
By Bjorn Fehrm, Henry Tam and Andrew Telesca.
December 10, 2021, ©. Leeham News: Our aircraft has now achieved its first deliveries and is Entering Into Service (EIS) with our launch customer.
This covers one customer and one jurisdiction. As each country is sovereign in Airworthiness certification, we have work to do for each market we want to address.
Figure 1. A new 19 seater design, the Cessna 408 SkyCourier, started life as a cargo aircraft certified to US Part 23 standards. Here, the passenger version. Source: Cessna.
Bjorn’s Corner: The challenges of airliner development. Part 32. Aircraft delivery and EIS
By Bjorn Fehrm, Henry Tam, and Andrew Telesca
December 3, 2021, ©. Leeham News: Last week, we went through typical problems by the start of serial production, such as weight creep and traveled work.
Now we discuss the ins and outs of delivering the aircraft to the customer airline and how we support the aircraft’s entry into service.
Figure 1. A new 19 seater design, the Cessna SkyCourier. Source: Cessna.
Bjorn’s Corner: The challenges of airliner development. Part 31. Serial Production problems
By Bjorn Fehrm, Henry Tam, and Andrew Telesca.
November 26, 2021, ©. Leeham News: Last week, we started our analysis of the serial production phase. If development is filled with revelations and problems to solve, production has it as well.
We start this week by looking at the beginning of serial production, where several issues are overhangs from development. There are areas of the aircraft, though we have achieved our Type Certificate, that are not quite to the maturity level we want for long-term serial production.
Figure 1. A typical aircraft Final Assembly Line (FAL) site. Source: ATR.
Bjorn’s Corner: The challenges of airliner development. Part 30. Serial Production
By Bjorn Fehrm, Henry Tam, and Andrew Telesca.
November 19, 2021, ©. Leeham News: Last week, we described how we finished the testing and the process to get our Type Certificate.
Now we look at the phase after Design and Production certification, the start of production, Figure 1. The upstart and ramp of production have many challenges. We will start the discussion with one that is often overseen, the cost of ramping production to full serial production rate.
Figure 1. Our program plan for the aircraft. Source: Leeham Co.
Bjorn’s Corner: The challenges of airliner development. Part 29. Finishing Flight tests
By Bjorn Fehrm, Henry Tam, and Andrew Telesca.
November 12, 2021, ©. Leeham News: Last week, we looked at our role in creating comprehensive crew training so the aircraft can be safely operated during its lifetime.
With maintenance and crew training docs and curriculums well underway we can return to our Flight tests and describe how we finish up the testing and get our Type Certificate.
Figure 1. The Type Certificate for the Part 23 Beech, now Textron, King Air series. Source: FAA.