Leeham News and Analysis
There's more to real news than a news release.
Bjorn’s Corner: Sustainable Air Transport. Part 49P. eVTOL production costs. The deeper discussion.
Subscription required
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.
Bjorn’s Corner: Sustainable Air Transport. Part 44. eVTOL operating costs.
By Bjorn Fehrm.
November 4, 2022, ©. Leeham News: This is a summary of the article Part 44P, eVTOL operating costs. It discusses the operational costs of a typical eVTOL flying a feeder mission from a city center to an airport.
The dominant cost factors are not the ones eVTOL companies love to discuss, like the electricity bills.
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 44P. eVTOL operating costs. The deeper discussion.
Subscription required
By Bjorn Fehrm
November 4, 2022, ©. Leeham News: This is a complementary article to Part 44, eVTOL operating costs. It discusses the typical operating costs we can expect from an eVTOL when used in an air taxi operation.
Despite the operation of such transports being years off, an eVTOL has dominant cost factors that can be estimated today.
Bjorn’s Corner: Sustainable Air Transport. Part 43. eVTOL IFR range.
By Bjorn Fehrm
October 28, 2022, ©. Leeham News: This is a summary of the article Part 43P, eVTOL IFR range. It discusses the range of a typical eVTOL flying a feeder mission from a city center to an airport during IFR conditions.
IFR conditions mean we have a dicey weather forecast for our airport destination and must plan with an alternate landing site where the weather forecast is better.
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 43P. eVTOL IFR range. The deeper discussion.
Subscription required
October 28, 2022, ©. Leeham News: This is a complementary article to Part 43, eVTOL IFR range. It discusses the typical maximum range we can expect from a certified eVTOL when it faces IFR weather conditions.
Flying in IFR conditions requires flight planning with increased reserves if the eVTOL can’t land at the destination airport and must divert to an alternate airport.
Bjorn’s Corner: Sustainable Air Transport. Part 42. eVTOL range.
By Bjorn Fehrm.
October 21, 2022, ©. Leeham News: This is a summary of the article Part 42P, eVTOL range. It discusses the range of a typical eVTOL flying a feeder mission from a city center to an airport.
The 42P article details the energy consumption for each stage in the mission and the range we fly. We summarize the results here.
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 42P. eVTOL mission range. The deeper discussion.
Subscription required
October 21, 2022, ©. Leeham News: This is a complementary article to Part 42, eVTOL mission range. It discusses the typical maximum range we can expect from a certified eVTOL by mid-decade.
We have described the vehicle and the mission data in the three previous Corners; now, we analyze the energy consumption for the mission and discuss the range we can achieve.