Robinson Marks 5,000th R44 Raven II Delivery

COLORADO SPRINGS—As Robinson Helicopters steps up development of autonomous and hybrid-powered versions of its light piston single R44, the California-based company has marked the delivery of the 5,000th R44 Raven II.

The milestone comes 33 years after the first delivery of the Lycoming IO-540 powered four-seat helicopter, and 36 years since the baseline Raven I model made its first flight in 1990. Multiple variants have since been developed including the Raven II, Clipper I and II, and the Cadet training variant.

Meanwhile, Robinson continues to invest in upgrades of the piston-powered family, and at this year’s Verticon helicopter convention unveiled a new Utility Interior with a set of more ruggedized materials for tough missions.

Delivery of the 5,000th Raven II to a dealer in Ecuador also comes as Robinson and Rotor Technologies continue development of autonomous R44 cargo and crop-spraying R550 retrofit variants dubbed the Air Truck and Spray Hawk, respectively.

A modified hydrogen-electric version of the R44 is also undergoing flight testing by United Therapeutics for organ delivery missions as a pathfinder for a planned follow-on hybrid R66 variant.

The hydrogen-electric helicopter effort evolved from earlier battery-electric aviation projects funded by United Therapeutics. From 2016 through 2018, the company’s organ delivery subsidiary Unither Bioelectronics, in partnership with Robinson, modified an R44 to battery-electric propulsion.