By Philip Butterworth-Hayes
“What if … you had a new propulsion technology that even at small thrust class could achieve an efficiency of >90%? And what if you realized that for the same total amount of power required, using 22 small electric motors is 4.7 times lighter than using one big electric motor? And what if you realized that by using many small electric motors, the cube-square law made thermal cooling become a simple passive solution, instead of requiring complex active liquid cooling systems to remove the low grade heat of one big electric motor? How would you design an aircraft to leverage such radical changes to how propulsion systems scale? How would aircraft capabilities change as propulsion, aerodynamics, and acoustics were all combined into a single unified highly integrated solution?”
This is how Mark Moore ,CEO, Whisper Aero, introduced the launch of the Whisper Jet at the AIAA Aviation Forum.
The concept for the new eVTOL integrates an electric ducted fan (EDF) quiet propulsion system with unconventional aerodynamics.
“We fundamentally questioned how electricity should be converted to thrust,” says the company in its website presentation. “Every component has been carefully considered with ultra low noise and efficiency from the beginning. Noise pollution and energy loss significantly hinder the adoption of regional electric flight as well as drone deliveries. So we engineered our electric jets to be 20% more efficient and 100x quieter than anything else on the market.”
The number of engines and the unconventional airframe design might surprise some in the industry but the company has raised USD32 million in Series A funding and taken the unusual step of targeting defence, as well as civil markets, in its new concept.
It has set itself some considerable technical targets to achieve, well beyond the scope of other, competing eVTOLs, based on achieving very high efficiency rates through using multiple fan blades, rotating at relatively slow speeds. Whisper Jet engines can be installed on different aircraft platforms to provide regional air service in trips of 50 to 500 miles, according to a company white paper.
“Whisper propulsion also enables ultra-quiet flights with greater efficiency at higher speeds. This opens the aperture to new C-UAS defense drones, multi-mission CTOL jets, high speed VTOL aircraft, and more,“ says the website.
The aircraft is currently at the concept stage; manufacturing will be undertaken by an industrial partner.
For more information
https://www.whisper.aero/
https://www.aiaa.org/aviation/program/aviation-session/whisper-aero-session