Less than a year after Whisper Aero unveiled its concept for an electric regional jet, the Tennessee-based company is proposing another use for its ultraquiet propulsion system: a 100-passenger electric airliner. 

Whisper Aero CEO Mark Moore revealed the “Whisper Jetliner” concept on Monday at the Ohio Air Mobility Symposium. The company has also submitted a proposal for the design to NASA’s Advanced Aircraft for Sustainable Aviation (AACES) program, which the agency launched last year to “stimulate innovation and the development of advanced conceptual designs and technologies for commercial subsonic aircraft that could enter service around 2050.”

The Whisper Jetliner utilizes a larger iteration of the same ultraquiet electric ducted fan technology featured in the Whisper Jet, a concept for a nine-passenger electric aircraft that the company presented last summer at the American Institute of Aeronautics and Astronautics Aviation Forum in San Diego, California. 

As with the Whisper Jet, a series of 22 ducted fans is integrated into the leading edge of the aircraft’s wing to achieve upper surface blowing—an aerodynamic concept that NASA pioneered with its Quiet Short-Haul Research Aircraft (QSRA) program in the 1970s. An upper-surface blown wing generates additional lift, which is especially useful for short takeoff and landing (STOL) vehicles with low approach speeds and steep approach angles.

According to Whisper, the Jetliner would have a battery-electric range of up to 769 miles (1,238 kilometers) using 804 Wh/kg battery cells. In a hybrid configuration with a 4-megawatt generator, the range would extend to 1,176 miles (1,893 km). It would require only 3,000 feet (900 meters) of runway to take off and land, whereas a comparable Airbus A220-100 model requires 4,800 feet. 

Whisper says its concept would also drastically reduce operating costs. “For a 700-mile flight, the Jetliners enabled by Whisper’s propulsion systems at full capacity would save 9,100 kg of carbon dioxide each flight, nearly 10 tons, as compared to a similarly sized aircraft flying today,” Whisper officials said in a written statement. For a 500-mile trip, energy costs for the Whisper Jetliner would amount to around $733 in electricity, whereas fuel cost for that same trip in a similarly sized commercial aircraft such as the A320 is around $2,100. 

While the Jetliner concept represents Whisper’s ambitions of decarbonizing aviation, the company has said that it does not intend to become an airframe manufacturer. Rather, Whisper intends to partner with aircraft manufacturers in bringing its proprietary propulsion system to market. In the meantime, the company is also exploring other possible applications for its ultraquiet ducted fans, including leaf blowers