An efficient propulsion system, developed by a Tennessee-based company, is soon expected to power a single-seat glider.

Whisper Aero has secured a $500,000 grant to help bring the company's motor concept off the drawing board and onto the testing phase.

Whisper Ultralight is an Aeriane Swift3, foot-launched glider modified with quiet electric ducted fans. Credit: Whisper Aero Whisper Aero has received funding to help modify a glider to flight ...