The skies are on the Nerdshala of getting busier — and louder — as drone delivery and electric vertical take-off and landing passenger aircraft move from startup Moonshot to commercialization. A former NASA engineer and former director of Uber’s Air Taxi Division is developing technology to ensure that more air traffic doesn’t equal more noise.
Mark Moore, who was until recently the director of engineering at Uber Elevate until it was acquired by Joby Aviation, has launched his own company called Whisper Aero. The startup, which came out of stealth this week, aims to design an electric thruster that it says will blend noise from delivery drones and EVTOLs more evenly into background levels, making them sound better to the human ear. Will be made almost imperceptible.
This is a formidable challenge. The solution to the noise problem is much more than simply turning down the volume. The noise profile is also characterized by other variables such as frequency. For example, helicopters have a main rotor and a tail rotor that generate two different frequencies, which makes them more irritating to the human ear than having them at the same frequency, Moore said in a recent interview. told Nerdshala.
Complicating the picture even more is that EVTOL companies are designing entirely new types of aircraft, which can produce a different acoustic profile than other rotorcraft (such as helicopters). The US military recently conducted a research study confirming that EVTOL rotors produce a type of noise referred to as broadband, rather than the tonal noise that is generated by helicopters. And as each eVTOL company is developing its own design, not all electric aircraft will generate the same level or type of noise.
Whisper is designing its scalable product to be adoptable across the board.
Moore said the idea for the company had been brewing for years. He and Whisper COO Ian Villa, who led strategy and simulation at Elevate, realized years ago that noise (i.e., less than it) was the key to landing air taxis.
“What was abundantly clear was that noise mattered most,” Villa said. “It’s the hardest barrier to break. And not enough of these developers were spending time, resources, mindshare to really unlock that.”
Helicopters have mostly been able to get away with their terrible noise profile because they are used so rarely. But eVTOL companies like Joby Aviation are envisioning far higher ride volumes. Moore quickly pointed out that companies like Joby (which bought Elevate in late 2020) are already developing aircraft that are several times quieter than helicopters, and are “a step in the right direction.”
“The question is, ‘Is this a step enough to drive significant adoption?’ And that’s what we’re focused on.”
Whisper is silent on the details of its thruster design. It has managed to attract investments of about $7.5 million from firms such as Lux Capital, Menlo Ventures, Kindred Ventures and Robert Downey Jr.’s Footprint Coalition Ventures. It also aims to convert its provisional patent with the United States Patent and Trademark Office sometime next year.
From there, the startup envisions launching into the small drone market around 2023, before progressively reaching air taxis. Moore said the goal is to build thrusters and into vehicles by the end of the decade. Should the first generation of EVTOL go to market in 2024 (as proposed by Archer Aviation and Joby), Whisper’s product could potentially appear in the second generation of EVTOL.
In the meantime, Whisper will continue to test and work out the remaining technical challenges — not the least of which is how to manufacture the final product at a reasonable cost. Whisper is also preparing to conduct dynamic tests in a wind tunnel, in addition to static tests conducted at Tennessee Headquarters, some in partnership with the US Air Force.
“It’s quiet enough to blend into the background noise,” Moore said. “We know this and that’s the technology we’re developing.”