Thomas Sleightholm, writing in eVTOL Insights, reports, “Whisper Aero has completed the first piloted flights of its eQ250 electric ducted-fan propulsion system aboard a modified Swift 3 glider, marking a move from ground testing to flight testing for the company’s electric propulsion technology.” Whisper chose the Swift because its 26:1 lift-to-drag ratio allowed evaluation of, “Propulsion performance and aircraft integration under FAA special airworthiness conditions.” The light weight and low drag of the craft ensured good performance on the twin propulsors. With a gross weight of “over 600 pounds,” the Swift is no ultralight. But wifh 170 pounds of thrust push it quietly along, performance is sprightly, including a 1,200 foot-per-minure rate of climb. Taking a bit of editorial license, we’ll assume a gross weight of 650 pounds for the Whisper Swift, including 16 pounds each for the propulsors, more for batteries, and additional for the five Electrical Power Systems Epic 1.0 Energy Modules. Even with the added weight, the …
