Leeham News and Analysis
There's more to real news than a news release.
Leeham News and Analysis
- Bjorn’s Corner: Air Transport’s route to 2050. Part 25. June 6, 2025
- New RISE powerplant benefits from decades of GE research and development June 5, 2025
- Engine makers emphasizing durability, reliability June 4, 2025
- Boeing CEO: Lessons learned are key to certification of 737-7/10 and 777X June 2, 2025
- Digital twin is a key to JetZero’s hopes for Blended Wing Body entry June 2, 2025
Bjorn’s Corner: The challenges of airliner development. Part 11. The Program Plan.
By Bjorn Fehrm, Henry Tam, and Andrew Telesca.
July 9, 2021, ©. Leeham News: Now that we have done the basic market research we should scope the program. To do this we need to understand what aircraft we will develop and to what certification rules.
Our market research tells us to develop a 19 seat aircraft that can operate as a passenger and/or cargo aircraft outside the US and as cargo aircraft in the US. This enables us to certify it to FAA Part 23 and the equivalent rules of other National Aviation Authorities where we want to sell the aircraft.
Figure 1. The new Cessna SkyCourier Cargo/19 seat utility airliner. Source: Cessna.
Bjorn’s Corner: The challenges of airliner development. Part10. What aircraft to develop.
By Bjorn Fehrm, Henry Tam and Andrew Telesca.
July 2, 2021, ©. Leeham News: It’s time to start our aircraft project, where we discuss aircraft development from preliminary planning to fleet support and look at how the certification rules influence our work.
The first part of any aircraft project should focus on understanding the market your project will enter. Our project idea is to develop a Green aircraft for the 19 seat passenger market.
Figure 1. Beech 1900D 19 seat feeder airliner. Source: Wikipedia.
The true cost of Electric Aircraft
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By Bjorn Fehrm
Introduction
July 1, 2021, © Leeham News: In our Friday Corners, we analyze the development challenges of aircraft. We will launch a concrete project Friday where we intend to develop a 19 seat airliner. To make it interesting, it will be a Green aircraft. We focus on the Certification issues in the Corner series.
To complement it, we here look at the operating cost of a battery-based electric airliner, as there are costs that are often not presented to the public in the marketing of these alternatives. The operational costs for the huge batteries are too often forgotten.
Figure 1. Heart Aerospace ES-19 battery based airliner. Source: Heart Aerospace.
Summary
- Electric aircraft using batteries as energy stores are proposed for extreme short-range flights (below 200nm). The short flights shall make the weight of the batteries needed bearable.
- One advantage of these aircraft compared to today’s turboprops shall be their lower energy and maintenance costs. While this is true as long as we don’t count the batteries, including those in the maintenance costs changes the equation.
Bjorn’s Corner: The challenges of airliner development. Part 9. Size of the airliner.
By Bjorn Fehrm, Henry Tam, and Andrew Telesca
June 25, 2021, ©. Leeham News: We are closing in on our aircraft project, where we will go through an aircraft development from A to Z and look at how certification rules govern our work.
Before we decide what aircraft to develop, let’s look at how the certification rules break the market into segments based on cabin seating.
Figure 1. An example of a 50 seat airliner, the ATR 42. Source: Wikipedia.
Bjorn’s Corner: The challenges of airliner development. Part 8. Transport category rulings.
By Bjorn Fehrm, Henry Tam, and Andrew Telesca
June 18, 2021, ©. Leeham News: We continue our discussion about the Transport Category (FAA Part 25) certification rules.
Last week we talked about how much tougher the birdstrike protection is for Part 25. Now we look at the fuel tanks and the inherent explosion risk in these.
Figure 1. The Boeing 747-100 N93119 that flew TWA flight 800. Source: Wikipedia.
Bjorn’s Corner: The challenges of airliner development. Part 7. Transport Category Aircraft
By Bjorn Fehrm, Henry Tam, and Andrew Telesca
June 11, 2021, ©. Leeham News: Last week, we scaled a nine-seat aircraft to a 19-seat aircraft and examined some of the pros and cons of such a change. The aircraft are certified to the 14 CFR Part 23 rules in the US, labeled “Normal Category Aircraft“.
This week we scale the aircraft up one step further to understand product certification and operation rules for the larger Transport Category Aircraft (14 CFR Part 25) class.
The Bombardier Global 7500 is a Transport Category Aircraft (Part 25) as its gross weight is over 19,000lb. Source: Bombardier.
Bjorn’s Corner: The challenges of airliner development. Part 6. Adding seats.
By Bjorn Fehrm, Henry Tam, and Andrew Telesca.
June 04, 2021, ©. Leeham News: Last week, we examined operating and product certification rules related to 9-seater air taxis and commuters. We took the example of the new Tecnam P2012 Traveller to study the certification rules for a 9-seater. Now we upsize the aircraft to understand the pros and cons of adding extra seats.
The Viking Twin Otter, the only in-production 19-seater. Source: Viking Air
Bjorn’s Corner: The challenges of airliner development. Part 5. Developing to Cert rules
By Bjorn Fehrm, Henry Tam, and Andrew Telesca
May 28, 2021, ©. Leeham News: After an overview of different certification rules and discussions about why there are different rule sets, we now exemplify the rules by looking at specific aircraft projects and how the certification rules affect the design.
We start this week with the idea to certify a 9-seat mini-airliner like the Tecnam P2012 Traveller. It’s a recent development with US-based Cape Air as the launch customer.
Figure 1. Passengers boarding the 9-seat Tecnam P2012. Source: Tecnam.
Bjorn’s Corner: The challenges of airliner development. Part 4. How safe is safe?
By Bjorn Fehrm, Henry Tam, and Andrew Telesca
May 21, 2021, ©. Leeham News: After giving an overview of the types of certification rules last week we now describe why the rules can vary so much between projects.
We cover some general concepts around acceptable levels of safety that influence how the regulations get applied to specific projects.
Figure 1. Air vehicles and their classification. Source: Aviation & Flying.
Bjorn’s Corner: The challenges of airliner development. Part 3. Certification rules overview.
By Bjorn Fehrm, Henry Tam, and Andrew Telesca.
May 14, 2021, ©. Leeham News: The certification rules for different aeronautical vehicles are specific for each airworthiness jurisdiction. It means each country has its own rules for all the categories we listed in the last article. However, with the support of the International Civil Aviation Organization (ICAO), there is harmonization in many areas, especially around airport and airline operations. For airworthiness rules, most originated from dominant jurisdictions like the US FAA, whose rules have inspired the Canadian and European rules as well as many others.
As new technologies come to market, or new safety information is learned through testing, accidents, and incidents, the major regulatory agencies of the world constantly adapt with some rules harmonizing across jurisdictions and other rules diverging in different directions. It is an ever-evolving regulatory landscape that supports some of the safest transportation in the world, but it comes at a cost for companies as what was done in the past cannot always be expected to be accepted in the future, and the more global your desired market the more rules you need to understand and the more constraints your design will need to satisfy.
Figure 1. The EASA certification rules website. Source: EASA.