The hunt for the quietest evtol and flying car engines has begun, with a few different manufacturers throwing their hats into the ring.
Whisper Aero is one of these manufacturers.
They’ve raised $40 million and some military grants to go after highly efficient and ultra quiet engines. Trying the ‘more blades = quieter’ technique on their ducted fans, but the question is - how do you get more blades to be more efficient? That is not usually the case.
They questioned how electricity should be converted to thrust. Every component has been carefully considered with ultra low noise and efficiency from the beginning.
The Whisper propulsion system incorporates a specialized "propulsion disc," which functions as a fan. This fan distinguishes itself with an exceptionally high number of robust and rigid blades, interconnected at the outer edge by a reinforcing shrouding ring. Designed with a relatively compact diameter, this fan aims to maintain low blade tip speeds, even as it rotates at the RPMs pertinent to flight operations.
The company's propulsor is supposedly "100-500 times quieter than the ducted fans, and 100-1,000 times quieter than the open propellers." (at least according to the data we’re shown below) Given that ducted fans are pretty loud, I’d be happy with that. Especially if flying cars are buzzing our skies in the near future.
The Whisper Jet concept has an odd appearance, featuring a Blohm and Voss Outboard Horizontal Tail (OHT) configuration reminiscent of Virgin Galactic's VSS Unity(another odd duck). Propulsion units are arrayed along its inner wing surfaces. In theory, it could accommodate a pilot and nine passengers, travel up to 200 miles (322 km) on a single battery charge, reach speeds of up to 288 mph (463 km/h), and use conventional runway takeoff and landing (CTOL) procedures. With a hybrid system, its range could extend to around 500 miles (800 km). That is pretty outstanding for flying car/evtol range.
However, it's essential to note that the Whisper Jet is just a concept, folks. Whisper is primarily focused on selling its propulsion system rather than becoming an aircraft manufacturer. Gotta make money somehow, right? The company suggests that this propulsion system would work well for short takeoff and landing (STOL) aircraft, drones of various sizes, and potentially, in the future, electric vertical takeoff and landing (eVTOL) air taxis. They are even developing a range of fan diameters, including 4 inches, 10 inches, and a 24-inch option specifically tailored for use in the AFWERX High-Speed VTOL program, where it will compete with other intriguing propulsion technologies (Jetoptera is also part of this program).
So - here’s the take away. Low noise, efficiency, and real world applications for anything that uses a ducted fan (flying cars) Let’s get the party started!