Company Says The System Will Increase Efficiency, Affordability
A scale-model helicopter with rotors driven by compressed air is being displayed this week at the Paris Air Show. The aircraft, dreamed up by Belgian startup company Sagita, is approximately 85 percent efficient, according to Sagita's engineers.
The online publication Gizmag reports that the Sherpa's propulsion system starts with an air intake at the rear of the aircraft which leads to a compressor. That compressor diverts air to the engine for combustion, and also to two turbines which power the contra-rotating rotors. The compressed air uses waste heat generated by combustion as well as exhaust gasses to increase its temperature to 212 degrees Fahrenheit before being routed to the turbines, meaning no additional cooling system is required, according to the company. It also eliminates the need for a tail rotor, they claim.
Sagita plans for the Sherpa to be a two-seat aircraft with a useful load of 377 pounds, an 85 knot cruising speed, and a range of just over 200 nautical miles. Sagita Director and Sherpa inventor Hubert Antoine told Gizmag that the technology could also be applied to much larger helicopters as well as UAVs.
The company hopes to have a flying prototype in two years, with sales beginning in 2016. It has been in development since the company was founded in 2008.
(Pictured: Electric-powered Sherpa scale model from YouTube video)