Whisper Aero, a U.S. start-up developing quiet electric propulsion systems, revealed a family of autonomous aircraft concepts for contested logistics missions on May 6 during the Special Operations Forces (SOF) Week event held in Tampa, Florida. With funding from the U.S. Air Force, Whisper said it will spend the next four years building and flying multiple full-scale prototypes as it strives to bring the technology into service on a program of record.
Collectively dubbed Collaborative Logistics Aircraft (CLA), the concepts are designed to work in tandem to deliver critical payloads in combat zones. “Instead of one singular platform, Whisper believes that cargo missions will increasingly rely on distributed fleets of right-sized logistics UAS capable of operation from austere runways at any time of day,” the company said in a statement.
During SOF Week, Whisper showcased two fixed-wing, hybrid-electric CLA models: the CLA Light and CLA Heavy. Both variants feature Whisper’s eQ250 electric ducted fans, which are integrated into the wing in what the company calls a “jetfoil” array.
The CLA Light is a clean-sheet uncrewed aircraft system design capable of carrying 500 pounds of payload up to 200 nm. Without a payload, the 1,300-pound Group 3 UAS would be able to fly more than 2,000 nm, according to Whisper. It features 12 eQ250 propulsion units, a 40-kilowatt powerplant, and a small battery. With a 50-foot ground roll, it will be capable of short takeoff and landing (STOL) operations.
Building on the learning from the CLA Light, the subsequent CLA Heavy prototype will be a 10,140-pound Group 5 UAS in the form of a retrofitted nine-passenger airplane. Although it is intended for cargo, the CLA Heavy could potentially be reconfigured for other missions requiring quiet STOL flight capabilities. Equipped with a 600-kilowatt powerplant, the hybrid-electric aircraft will have a 300-foot takeoff/landing ground roll, a top speed of 250 knots, and a range of 800 nm when carrying 3,000 pounds of payload or 3,000 nm empty.
Whisper aims to begin flying a prototype of the CLA Light in 2027 after the company achieves the first flights of the Whisper Ultralight electric glider, which it is developing in partnership with Tennessee Tech University. The company said it is working with other manufacturing and autonomy partners that it plans to announce soon.