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  • Writer's pictureNed Patton

All Electric Aircraft are All Composite Too



Archer Electric eVTOL Aircraft

I thought with this post I would revisit electric aircraft, which because of the strength to weight ratio benefit that they can get from composites are nearly all composite material structures. Most of these are intended to be air taxis – like the Archer Electric aircraft pictured here, but there are a few that are making somewhat larger and more conventional takeoff and landing airplanes.

Electric aircraft fall along two lines, battery powered electric aircraft which are usually somewhat smaller airplanes and are nearly all composite, and hydrogen-electric (fuel cell) aircraft that can be much larger, and don’t necessarily have to be all composite because they carry fuel on board in the form of hydrogen gas.


The smaller and battery powered aircraft – which are all composite – also are quite varied. Like the Archer eVTOL aircraft pictured above and the Diamond DA40 Trainer pictured here as well. The DA40 has completed several test flights to date, and is expected to achieve its FAA certification sometime this year or early next year. This airplane is capable of up to 90 minutes of flying time and has a DC fast charging system that allows it to recharge in about 20 minutes.

And, of course, since this is a newsletter about composites, this aircraft is also an all composite airframe and shell, which allows for more weight to be allocated to the batteries. It is the composite airframe that permits this aircraft to fly and have the sort of range and time aloft that it has.

This is true also of the Archer eVTOL, as well as the Joby all electric aircraft that I talked

about a few posts ago, and is also pictured here as well. Joby has a contract worth $131 Million to deliver up to 9 of these little air taxis to Edwards Air Force Base. And, of course, the Joby is an all composite aircraft as well. Their VTOL all electric, all composite air taxi has achieved FAA certification, and is ready for prime time. Prior to being ordered by Edwards AFB, air force pilots flew the aircraft and became the first to achieve transition flight (from vertical to horizontal) in an eVTOL aircraft as what is called “Sole Pilot-in-Command”. That means that one pilot took the aircraft off vertically, transitioned to horizontal flight, maneuvered around the air base to test the handling and flight characteristics of the aircraft, and successfully landed the aircraft vertically at the air base.

It is primarily carbon fiber that enables these aircraft to be light weight enough and stiff and strong enough to enable electric flight. The weight savings from moving from aluminum to a carbon fiber / epoxy monocoque structure, as long as the aircraft is a clean sheet of paper design intended to be made using carbon fiber composites, can be as much as 50%. This has of course also been recognized by both Boeing and Airbus, as evidenced by the 787 and the A350 – which I have also previously talked about in these newsletters.


Of the more conventional takeoff and landing type of all electric, all composite aircraft the Eviation Alice is probably one of the first larger battery electric aircraft to achieve FAA and European certification. Eviation, initially formed in Israel, is now headquartered in Arlington, WA and builds its aircraft there. They have over a $2 Billion backlog for this all composite, battery electric aircraft. The Alice comes in two versions, cargo and passenger. And it is capable of carrying 2500 pounds of cargo or passengers for 250 nautical miles at 260 knots. That means that the Alice is poised to become a short hop regional commercial aircraft in the not too distant future. They have orders from Mexico’s Aerus, the UK’s aircraft leasing company MONTE, and Australia’s Northern Territory Air Services in Alice Springs.

For Boeing and Airbus, the thinking is that batteries have not progressed to the point that a battery electric aircraft the size of a modern commercial transport aircraft will be achievable in the near future. That is not to say that they aren’t investigating zero carbon emissions aircraft, just that they don’t think that battery technology will be available in time for them to field a battery electric aircraft. They have instead done a tremendous amount of investigation and also poured money into hydrogen electric fuel cell driven aircraft.


Boeing has focused recently on near term deliverable all electric, carbon fiber composite aircraft and has actually put $450M into a small aircraft company that is building an autonomous air taxi. The company is Wisk Aero and they expect to be the first to achieve FAA certification for a flying electric taxi. Wisk is based in San Francisco and New Zealand, and was originally spun out of a partnership between Boeing and Kitty Hawk.


Also in this space, there is a demonstrator that Alaska airlines has funded that will use Bombardier Q400 (Dash 8-400) turboprop commuter aircraft and replace the engines with hydrogen electric power plants developed by ZeroAvia in Brazil. ZeroAvia has been developing its hydrogen electric power plant and has received certifications for prototype aircraft in both the US and the UK.


Airbus initially funded an aircraft that had ducted fans powered by electric motors, and still has an idea that this may be the future, but they have recently funded the development of a blended-wing body all composite aircraft that will be powered by hydrogen fuel cells running electric motors driving turbofans. What they are working on developing with their engine partners is a hydrogen electric turbofan engine that has the capacity to power an aircraft that can carry more than 200 passengers for more than 2000 nautical miles. Of course, the fuel needs to be liquid hydrogen to get enough fuel in a small and compact space to power the aircraft for that kind of range, but it does appear that if they maximize the use of carbon fiber composites, which should be fairly straight forward with their blended-wing body aircraft. This would be a revolution in commercial aviation and can only be enabled using carbon fiber composites.

As you can see, with the reduction in the cost of high performance carbon fiber, and the advent of higher capacity energy storage systems, both batteries and hydrogen, electric aviation is coming, and has the capacity to replace petroleum powered aircraft by on the order of 2050 or so. With the rapid advances in battery technology and the maturation not only of the carbon fiber composite business, but also the maturation of the engineers and designers of all new concept airframes like the Airbus ZEROe blended-wing design, there is the distinct possibility that the air transportation industry will cease to be the cause of greater than 25% of the carbon emissions into the atmosphere. At least that is the hope and dream of today’s all composite all electric aircraft developers.

That’s about it for this week. I’ll be back next week with another post both here and on LinkedIn (where this is reposted from www.nedpatton.com). And, please check out the pre-sale link for my book about composites which should be out in late July - https://mcfarlandbooks.com/product/The-String-and-Glue-of-Our-World/. I will know more about the release date of the book once I get proofs of the book to review and approve. Hopefully I will see those soon.

See y’all next time.

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