While Covid-19 had a detrimental effect on so many industries – including hospitality, entertainment, and beauty – the pandemic has arguably affected the aerospace industry most.
At the heart of lockdown, many companies were wondering if commercial aircraft would ever be in use again.
Now, while things are starting to get back to normal – aided by government investment in defense aerospace and companies’ investment in safe, hygienic travel – there is still the sense that there has been a sea change in the industry.
One burgeoning industry that has come to the fore is that of air taxis – electric aircraft designed for short journeys and a small number of passengers, otherwise known as eVTOL (electric vertical takeoff and landing) is a type of aircraft that uses electric power to hover, take off, and land vertically.
A report from IDTechEx, published in March 2011, suggests that the market for eVTOL air taxis could grow to US$14.7 billion by 2041. According to the report, many global aerospace and automotive companies are ramping up their interest in eVTOL aircraft, with companies such as Boeing, Airbus, Embraer, and Bell running ongoing eVTOL development programs, and aerospace suppliers Raytheon, GE, SAFRAN, Rolls-Royce, and Honeywell, investing in eVTOL technologies. (Figure 1.) New eVTOL start-ups include Volocopter, EHang, SkyDrive, Vertical Aerospace, Jaunt Air Mobility, Archer Aviation, and Beta Technologies.
Quieter and cleaner than traditional helicopters, air taxis could be a way for commercial aerospace to get back on its feet and look to future investment. Proponents of the technology say that the air taxis could also be relatively cheap and fast to use.
Lightweight vehicle
An important aspect of air taxis is, of course, their lightweight characteristics, and that’s where composites come in. Toray Advanced Composites, based in the Netherlands and Nottingham, UK, has an established reputation as a provider of thermoset and thermoplastic composite materials for aerospace. In December 2020 it completed a long-term supply agreement with Joby Aviation for the composite material used for its aircraft.
Joby Aviation is a California-based venture-backed aerospace company founded in 2009 which is currently developing an eVTOL aircraft to operate as an air taxi service. The company’s aim is to deliver people to their destination five times faster than driving, reduce urban congestion, and accelerate the shift to sustainable modes of transit.
The eVTOL aircraft is all-electric, offers vertical take-off and landing, and has a range of up to 150 miles and a top speed of 200 mph. Carbon fiber materials are used throughout the vehicle structure, propulsion systems, and interior components. According to Toray, every aspect of the Joby Aircraft is being optimized for maximum utilization for urban transport and Toray’s carbon fiber materials are a key component of achieving their goals.
‘Electric aircraft require proven materials that have high-strength and are very lightweight,’ a press release said. ‘Carbon fiber composite materials provide the strength-to-weight ratio needed for electric aerospace applications in order to maximize the range and speed of the aircraft.’
Toshiyuki Kondo, CEO of Toray Advanced Composites, is a fan. ‘As children, we dreamed of being able to fly to a destination in a fraction of the time it would take to drive,’ he said. ‘That is no longer a fantasy. The electric air taxi is becoming a reality and we at Toray are perfectly positioned to meet the industry’s needs today and in the future. It’s a very exciting time.’
Joby Aviation has spent more than a decade developing its aircraft and plans to bring it into commercial operation as early as 2023.
‘Joby Aviation is developing a piloted, all-electric, vertical takeoff and landing passenger aircraft which it intends to operate as a fast, clean, quiet and affordable air taxi service,’ Katie Pribyl,
Joby spokesperson, told me. ‘Over time, the cost of these trips per passenger is expected to be on par with an Uber X. The aircraft will be part of an on-demand commercial aviation service similar to rideshare and will not be available for individual sale.
‘Instead of driving nearly 44 miles from Los Angeles Airport to Newport Beach – a trip that takes an hour and fifteen minutes – a Joby aircraft will get you there in just fifteen minutes with zero emissions.’
The Joby Aircraft utilizes carbon fiber not only in the aircraft body, but also in its propulsion systems and interior components. For Joby, carbon fiber material is essential to ensuring the success of the project. ‘Carbon fiber is critical to bringing our vision of safe and affordable zero-emissions flight to reality,’ the company said. ‘In order to meet our speed, range, and payload targets, the aircraft must be both robust and lightweight.’
Strength and lightweighting capabilities are not the only benefits of using carbon fiber. ‘Carbon fiber most definitely imparts strength, but that’s not all,’ Joby noted. ‘It is an ideal material from which to build aircraft structures and parts because it is lightweight, incredibly strong and has a smooth, aerodynamic finish. As a result, carbon fiber reduces energy consumption, increases payload, extends flight range, reduces part count and enhances durability.
The Joby Aircraft is vertically integrated by necessity, according to Joby. ‘For example, the electric motors are designed and built in-house. This allowed us to incorporate the exact component needed in the most efficient way possible, thereby reducing part count and weight. There are numerous examples like this throughout the aircraft.’
Test flight
Toray is not the only carbon fiber composite manufacturer to book a seat on the air taxi flight. In February 2021 chemical giant Solvay reported that it would supply composites, adhesive technologies, and technical support to a UK-based aerospace manufacturer based in Bristol, UK that also designs and builds zero carbon eVTOL aircraft. Vertical Aerospace’s VA-1X passenger air taxi will will be able to carry four passengers and one pilot for 100 miles (160 km) at cruise speeds of 150mph/240kmph, according to Solvay.
The companies aim to successfully develop the first flying prototype scheduled for a test flight in September 2021. Aircraft certification is planned for 2024 with commercial services starting shortly after.
‘Solvay is proud to partner with Vertical Aerospace, a pioneer in sustainable aviation technologies, whose VA-1X aircraft is set to revolutionize the way we travel,’ said Carmelo Lo Faro, president of Solvay Composite Materials’ global business unit. ‘By providing the performance required to operate safely and maximize range, while facilitating the processes needed for mass production, our advanced materials will be key enablers to the mass-adoption of eVTOLs.’
In January 2020, German carbon fiber specialist SGL Carbon reportedly began serial production of landing gear made from braided carbon fiber material. Plans are for the landing skids to be installed in around 500 air taxis worldwide over the next two years.
The air taxis will be powered by several electric motors. To optimize the range of the taxis, every single gram counts. Measuring about two meters in length and 1.5 meters in width, the ultra-light landing skid will weigh less than three kilograms, making it about 15 percent lighter than a similar component made from aluminum. This increases the potential flight time capacity of the air taxi which is a key differentiator for the air taxi operator.
The landing gear was developed in close collaboration between customer experts and specialists from SGL Carbon. The carbon fibers for the component are produced at the SGL Carbon plant in Muir of Ord, Scotland. The final part is being manufactured at the SGL Carbon site in Innkreis, Austria.
Market demand
Also in February 2021, Triumph Aerospace Structures, a company based in Pennsylvania, USA, which makes reinforced thermoplastic aircraft interiors and other aerospace composites, received a Small Business Technology Transfer (STTR) contract from the US Air Force Research Laboratory to research the integration of thermoplastics in an eVTOL aircraft conceived by Jaunt Air Mobility, also based in the US.
Jaunt Air Mobility is developing the Journey, a four-passenger, single pilot, all-electric aircraft with thermoplastic composites as its primary structure, the company says. As well as commercial travel, the aircraft could be used in the military, cargo delivery, disaster response, humanitarian aid, and logistics missions.
According to Martin Peryea, Jaunt CEO, the company plans to produce 2,500 vehicles per year at each of its manufacturing centers. ‘High-rate production solutions are needed to meet this unprecedented aircraft market demand,’ he said. ‘Future eVTOL aircraft will require low-cost thermoplastics as traditional thermoset composites cannot meet production rates and cost targets.’
Georgia Tech is partnering with the companies and will develop an internal structural layout for a thermoplastic composite wing and design allowables for the material system.
