Silent aerospace propulsion with Whisper Aero’s Ian Villa

Ian Villa is COO and co-founder of Whisper Aero, an aviation and aerospace company developing ultra-quiet and electric propulsion systems for aircraft, drones, and other air-moving applications.

What does Whisper Aero do? 

We build cleaner, quieter, more efficient propulsion solutions for air mobility and air management. Whisper Aero harnesses the power of air to develop technologies that move air efficiently on the ground and propel vehicles through the sky.

My background has always been in aerospace. I earned a bachelor’s and master’s degree in aeronautics and astronautics from Stanford University. I joined Northrop Grumman’s advanced design team, working on “clean sheet” projects—meaning brand-new aircraft. In 2017, I joined Uber’s aviation division, Uber Elevate, where I was responsible for all of our original equipment manufacturer aircraft partnerships. I brought in companies such as Boeing, Bell and Embraer, as well as larger names like Hyundai and other nontraditional manufacturers, all developing new air taxis on their own dime.

By the end of my time there, I was head of strategy, leading system simulation efforts to help us understand how the future of aviation might look for drones, jets and air taxis. Mark Moore, my co-founder, and I decided to start Whisper Aero because we saw a future where quieter propulsion would be needed to move things through the sky more cleanly, efficiently and quietly. More importantly, it had to be affordable so the masses could press a button and get a flight whenever they needed.

What is Whisper Aero’s core technological innovation? 

Our technology is focused on making propulsion cleaner, quieter and more efficient. To achieve this, we target all three goals at once. The first challenge we addressed was building a fan with a high blade count that produces much less noise. We shift the tones that people typically hear into the ultrasonic range, beyond human hearing, while still keeping it safe for dogs, cats, birds and fish.

The pressure pulses we generate to create thrust are much more benign. Instead of producing a large pressure pulse, like one blade of a five-blade propeller, we create a more laminar flow with gentler pulses across many blades. This results in more efficient thrust. There is no gap between the blade tips and the duct, which improves efficiency by about 7 percent. The advantage of this high blade-count fan is that, whether it is four inches or four feet in diameter, we can still achieve more than 90 percent fan efficiency. This is a major breakthrough for air-moving products, whether they are small enough for your home or large enough to propel an aircraft through the sky.

How does this technology scale from leaf blowers to advanced drones?

These are electric ducted fans whose efficiency remains consistent regardless of size. If you have a thruster that can generate 80 pounds of thrust and you want to move up to 480 pounds of thrust, traditionally you would need to design a new fan or engine. That process would cost billions of dollars, require a full team of engineers, and take a significant amount of time, effort and energy.

For us, instead of building a new fan, we simply use six of the 80-pound thrusters to achieve 480 pounds of thrust. We lose no efficiency, save considerable time and improve unit economics. The thrust scale independence, enabled by the fan’s inherent efficiency, allows us to integrate these fans in new ways. We do not need to design many different fans; we can use multiple fans in a distributed fashion—what the industry calls distributed electric propulsion—to propel larger aircraft or move more air on the ground.

We have proven this approach in two ways. On the ground, we built prototype leaf blowers with a fan about 5 inches in diameter. Many golf courses and landscaping crews needed a way to move large volumes of air to clear leaves. Rather than building a single, improved handheld leaf blower—which we already accomplished—we combined 10 of our existing leaf blowers into a specialized blower that can be towed behind golf carts. Because they are all electric, we avoided complicated fuel lines and simply used wires to supply electricity to each fan, resulting in 10 times the thrust with a large battery. The system is more efficient, quieter and allows crews to clear leaves earlier in the morning without disturbing the neighborhood.

The benefit in the air is even more straightforward. You can use the same engine on multiple airframes, whether the aircraft weighs 1,300 or 10,000 pounds. For aircraft operators, this means lower maintenance costs. You can have line-replaceable engine units and train maintenance personnel to service multiple aircraft using the same engines. These electric engines have fewer moving parts. The only real moving part is the bearings. The time between overhauls—an important metric for engine maintenance—can be much longer. There is no combustion, so you avoid the high-temperature wear and tear common in turbine engines.

How competitive is the electric propulsion industry?

It is still early days, and this feels like a gold rush for electric aviation. In the past 10 years, people have been working to prove that flight powered by electricity is possible. To move quickly, some have taken shortcuts, such as attaching a propeller to a motor. But if you look at commercial airplanes today, most passengers fly on jets like the Boeing 737 or 777, which are powered by turbofan engines, not propellers.

This shows there is a need for speed and greater efficiency at higher speeds, and it highlights the limitations of propellers at those speeds. We are now at a point where people believe electric aviation is real because they can see it. Electric vertical takeoff and landing aircraft are flying today. The question is no longer whether electric aviation can work, but whether it can work for the masses in a way that is efficient and practical. We believe electric ducted fans are the answer.

Others are also exploring electric ducted fans, but not as many, since the field is still new. Many in the sector are using traditional aerospace methods to approach the problem. While companies like Rolls-Royce and Pratt & Whitney have talented engineers, starting from established practices can make it harder to challenge old assumptions with new technologies like electric motors and controllers.

We believe this gives us an advantage. We are taking the best of traditional aerospace, but also questioning assumptions and returning to first principles to design electric propulsion. We are integrating it into aircraft in a way that makes sense and delivers benefits greater than the sum of their parts.

How is the defense sector driving advances in electric aviation?

There has been a push and pull between the government and commercial sectors in electric aviation. The first proof points for electric aviation began with my co-founder at NASA. If you look at the American Institute of Aeronautics and Astronautics and citations for electric aircraft and distributed electric propulsion, Mark Moore’s name appears most often. He is widely regarded as the godfather of electric vertical takeoff and landing aircraft, or eVTOL—a term he coined.

He started in government but quickly brought in industry partners such as Joby Aviation to advance the technology. After conducting tests in the desert with a full-scale distributed electric propulsion wing, he decided not to continue developing the technology at NASA. Instead, he pitched the idea of flying Ubers to the Uber CEO. That led to the creation of Uber’s aviation division, which launched Uber Copter flights in New York City and Uber Eats drones that delivered the first Chicken McNuggets beyond visual line of sight in San Diego.

Today, government and commercial industries are advancing the field together. The Department of Defense (DoD) also became involved, recognizing what NASA and industry were achieving. The Air Force launched initiatives such as Agility Prime to support the sector. After losing ground in the small drone market to China, the DoD did not want to fall behind in this new frontier of aviation. The DoD has invested not only in large companies but also in building a healthy ecosystem of electric aviation technologies and supporting innovations for both commercial and defense applications. In the commercial sector, many companies are now public, allowing the market to evaluate their products.

On the defense side, more of these technologies are reaching flight tests. The DoD can now assess their merits and adapt those that originated in the commercial world for defense needs. At Whisper, we have focused on dual-use applications from the start. In 2020, we saw strong momentum in the commercial sector but some lag on the defense side. Our first two contracts were with the Air Force to begin research and development that would prove our technology. Today, we are moving toward flying our hardware on platforms that matter to them.

What are the main advantages of collaboration between the commercial and defense sectors?

If you look at past achievements in the United States, such as those at Bell Labs or during the early days of NASA and its predecessor, the National Advisory Committee for Aeronautics, many major advances in science occurred when the commercial sector’s needs aligned with the government’s vision for breakthrough progress.

Sometimes, innovation requires a government willing to make bold investments and a commercial industry ready to support or match those efforts. Often, consumers are not aware of research innovations or what may be coming next. The government, on the other hand, is often aware of potential scientific breakthroughs but may not know how to commercialize them. True innovation frequently happens at the intersection of these two worlds, where different mindsets and perspectives meet. That intersection is essential for deep science and technology innovation.

What are Whisper Aero’s top priorities for the next 12 months?

The focus is on achieving proof points with aircraft equipped with our propulsion systems to demonstrate their full capabilities. Over the past four years, we have shown that our electric propulsors are cleaner, quieter and more efficient than any others on the market. We have completed demonstrations and tests at military experimentation sites.

Now, it is time to take that technology into the air. We have flown our systems on our own drones in civilian airspace. By the end of the year, we plan to integrate our larger thrusters onto a glider for powered gliding flights. These tests will be conducted commercially in Tennessee, where the state has provided $500,000 in funding for the effort.

After completing those initial tests, we will move to DoD test ranges. In addition to the glider, we have announced a project called Collaborative Logistics Aircraft. There is a significant need to improve logistics, save fuel and sustain air power in new ways. Currently, the industry relies on aging cargo assets, many of which date back to the development of the C-130 transport aircraft.

With advancements in autonomy and hybrid-electric propulsion, we can now move fleets of vehicles more efficiently. It is logical to develop a 21st-century autonomous cargo logistics vehicle. Our propulsion system enables the Department of Defense to operate these aircraft from contested areas, including locations with less maintained airfields and shorter runways. We plan to conduct the first flight tests of these vehicles within the next two years.

How do you define deep tech?

Deep tech involves deep science, and often that means moving atoms and not bits.