• 11 Nov 2023 06:02 AM
• 0

Whisper Mode

By Richard Whittle
Vertiflite, Nov/Dec 2023

Whisper Aero isn’t blowing off aviation but has a spin-off idea far more down to earth.

Electric aircraft pioneer Mark Moore and fellow Uber Elevate veteran Ian Villa founded their company Whisper Aero three years ago to develop ultra-quiet, ultra-efficient electric propulsion for pretty much anything that flies. But they took their technology to Kentucky in October to demonstrate a literally mundane use for their ducted fan technology: leaf blowers.

“We’re doing live demos of our leaf blower with competitor leaf blowers every few minutes,” Moore said in an Oct. 18 Zoom interview from the 40th annual Equip Exposition. The massive outdoor equipment show, staged at the sprawling Kentucky Exposition Center in Louisville, Kentucky, featured displays of everything from heavy backhoes to hedge trimmers.

Chief Executive Officer Moore and Chief Operating Officer Villa founded Whisper Aero primarily to develop electric propulsors for aircraft quiet enough to let them blend into ambient urban noise as they fly. But engineers at the company’s development complex, a secluded former resort in Crossville, Tennessee, have been working on near-silent fans for consumer goods, too.

“Stove top fans, HVAC [heating, ventilation and air conditioning] systems, bathroom fans — there’s just so many devices in our world that move air,” Villa said, “and so many of them are noisy.”

Whisper Aero’s indoor exhibit at Equip Exposition (see photo), nestled among companies such as Husqvarna and Ohio Steel, featured a metal mesh bin of mock leaves used to demonstrate the company’s handheld, battery powered leaf blower prototype against blowers from established brands such as Stihl, EGO, Kress, Makita and Ryobi. “I can have a normal conversation with a normal voice with our leaf blower going,” Moore said. But with a conventional blower swirling the leaf box contents, “You’re screaming at the person next to you [to be heard] and need ear protection.”

Whisper Aero’s design, in development for about a year, features a white composite, 3D-printed body that houses a version of the company’s unique, electric, ducted-fan design. Whisper Aero’s features a high number of tightly packed blades made of pressure-injected, molded, chopped carbon fiber. The blade tips are held by a spinning rim within the duct, which keeps the blades from tensioning and losing their shape at speed.

Consumer Reports, which published leaf blower ratings in September, tests noise at the ear of the operator and at 50 ft (15.2 m). “The best models keep volume below 65 decibels, while the worst exceed 85 decibels,” the magazine said. “At 85 decibels, you’ll need ear protection to avoid hearing damage even from very brief use. At lower decibel levels, hearing protection is often still a good idea, especially if you’re using a leaf blower for a long stretch of time.” In-house tests employing American National Standards Institute (ANSI) standards found that Whisper Aero’s prototype produced 45 decibels at 50 ft, compared to 59 dBA for a Stihl BGA 300 blower, 57 dBA for a Ryobi RY404100NVM and 61 dBA for a Makita CBU02Z. Whisper Aero’s far quieter “Whisper Drive” blower enables “40% more airflow, 40x less noise, and 40% less energy use” than all three of those handheld, battery-powered blowers.

With the entire state of California and local jurisdictions across the United States banning noisier, air-polluting, gas-powered leaf blowers, forcing landscapers to go electric, Whisper Aero’s ultra-quiet leaf blower’s debut is timely. But the company won’t produce leaf blowers itself, Moore said, nor is its quiet leaf blower a marketing ploy. They took it to the Equip Exposition hoping to find established companies interested in licensing their technology. Based on “robust interest” at the Kentucky expo, Moore added, “I am confident that by the end of the year, or early next year, we will be in at least one — maybe initially we’ll do an exclusive agreement — [but] at least one major licensing deal.”

For millions of homeowners around the world, quieter leaf blowers truly can’t come soon enough.