The Vertical Flight Society (VFS) has identified 347 electric aircraft are being designed. As in the early days of electric cars, there are three categories of player. Firstly, there is the established industry (e.g. Boeing, Airbus, Bell, Sikorsky and Rolls-Royce) who are dipping their toes into the market with prototypes and demonstrators. Many are also aligning themselves with the second category, the well-funded start-up.
There are several very well-funded start-ups that could become the Tesla of the air mobility world. Elon Musk has hinted about an electric aircraft, but also says batteries are still too heavy. A great example of a well-funded start-up is Joby Aviation, who has raised USD$820 million from credible investors that include Toyota. Joby Aviation are developing a multi-tilt rotor four-seater with a range of up to 240km. They have recently joined forces with Uber and expect to be operational by 2024.
Another is Ehang, the Chinese air taxi company has a market value of USD$1.4 billion. In November 2020, in Seoul, Korea, they demonstrated their two-man aircraft with 3.6km journey using an 80kg bag of rice in place of a person. Perhaps one of the most promising start-ups in Europe though is Lilium who have raised USD$375m. Their full-size, tilt wing, five-seater prototype first flew on the 4th March 2019. Other credible players include Volocopter (Germany), Dufour (Switzerland), Kitty Hawk (USA and linked with Boeing), Vertical Aerospace (UK) and Archer (USA). Finally, there are a large number of more hopeful aspirants who may or may not be credible.
For most of these start-ups the business model is similar. The idea is to use these eVTOL (electric vertical take-off and landing) aircraft for short to medium journeys between places like Heathrow and central London. Significantly cutting down journey times for a modest price premium. Joby Aviation use the example of flying from Los Angeles Airport to Newport Beach, cutting the journey time from 1 ¼ hours to just 15 minutes. The target consumers for most business models are those who consider their time is of great value.
Most of the early adopters are using smaller drones for the delivery of medical supplies, foods and more general delivery. However, this really establishes the principle of operating autonomous light-weight drones over cities, paving the way for much larger human carrying drones.
Joby Aviation, who have completed over 1,000 test flights and agreed certification standards with the FAA in 2020, seems confident that it will be in commercial service by 2024. Lilium has also recently announced a partnership with Dusseldorf and Cologne/Bonn Airport to develop an air mobility zone. The company has also announced plans to set up an air mobility hub in Florida.
We can see that urban air mobility is far from a science fiction dream. So just how big could this market become? Morgan Stanley optimistically forecast 49,429 such aircraft by 2025, rising to more than 170,000 by 2040. Whilst the bulk of these will be small drones for package delivery, a significant proportion will transport people. This is the sector Magnomatics is targeting.
Lightweight reliable motors are a key enabling technology for these aircraft. Magnomatics technology has already been identified by NASA as ideal for air mobility. It has all the benefits of a mechanically geared motor without the reliability and maintenance issues of a mechanical gearbox. With torque density and reliability being viewed as a key metrics for this market, Magnomatics has already received enquiries from a number of serious players.
Magnomatics has reviewed competing motors being promoted for this sector – all use traditional metal structures. The leading example appears to be the Rolls-Royce P200 with a torque density of 30Nm/kg. However, like others this machine is liquid-cooled which introduces further mass, complexity and sources of failure. Magnomatics has made a further initial concept design that achieves 32.9Nm/kg, is also an air-cooled variant and results in a lighter overall system. This has been achieved by engaging in concurrent electromagnetic, thermal, materials and digital engineering. There is also a strong emphasis on the integrated use of composites.