Flying Towards The Green Dream

Hayley Everett

How in-flight testing technology is helping the next generation of sustainable eVTOL aircraft take flight

As the aerospace sector seeks to accommodate the increased importance placed on sustainability by governments, world leaders and climate activists around the world, companies in the sector are developing more environmentally-friendly ways to design and test aircraft and their components.

One company operating at the forefront of the Electric Vertical Take Off and Landing (eVTOL) sector is German electric jet aircraft developer Lilium, which is hoping to make the ‘green dream’ of electric flight a reality with its Lilium Jet.

The proprietary technology at the core of the Lilium Jet is Ducted Electric Vectored Thrust (DEVT), which has been refined through successive generations of aircraft demonstrators since Lilium’s founding in 2015. Proposed as an alternative to traditional jet engines which power around 95% of current commercial aircraft, Lilium’s electric jet engines rely on a single-stage rotor system driven by an electric motor to create propulsion. The jet engines are integrated into the aircraft’s wing flaps to increase payload and aerodynamic efficiency while reducing its noise profile. The engines also provide thrust vector control in order to manoeuvre the aircraft through each phase of flight.

Gas flow measurement and control solutions developer Chell Instruments is supporting the engineering and development of the Lilium Jet with its nanoDAQ-LTS air pressure measurement technology. Capable of withstanding extreme pressure, heat and vibrations, the nanoDAQ-LTS is designed for use within wind tunnels and during in-flight testing.

“We’re delighted to be working with such an exciting company, helping them trailblaze the search for sustainable electric jet propulsion,” says Jamie Shanahan, Sales Director at Chell Instruments. “Our technology remains at the forefront of traditional jet turbine development, so it’s fantastic we can also contribute to sustainable air travel.”

The nanoDAQ-LTS has proven a critical instrument in the development of the Lilium Jet, measuring air pressures on the aircraft during development. Able to sense tiny changes in pressure with extremely high levels of accuracy, the technology allows engineers to characterise the aerodynamics and validate computational flow dynamics of the jet’s aerodynamic surfaces and within its propulsion units. This data is then fed back to engineers via Ethernet and CAN outputs.

“Chell has been providing instrumentation into the demanding environments of F1 racing for many years,” adds Managing Director Nick Broadley. “The ruggedness of our pressure scanner technology is largely due to the latest generations of digital sensors, which enables us to provide performance close to lab-based equipment, even in hostile test environments.”

It is hoped aircraft powered by sustainable electricity, like the Lilium Jet, will help to significantly reduce global emissions in our pursuit of Net Zero. As such, the innovative technologies aiding the engineering and testing of these aircraft are of paramount importance to achieving the world’s climate goals, Broadley explains: “The aerodynamic performance of an electric jet will determine its success – in terms of propulsion, lift generation and the sensitivity of control surfaces. The nanoDAQ-LTS allows Lilium to understand all the important performance and control aspects and optimise the incredibly complex flow characteristics of the aircraft.”


Recent Issues