Sikorsky S-97 Raider Coaxial Helicopter Officially Unveiled, Claims 253 MPH Top Speed
and here we are thinking that coaxial rotor helicopters are pretty much dead. well, at least ‘dead’ in real aircraft and wouldn’t even dream of it being developed for military operations. we couldn’t be more wrong cos’ Sikorsky, the pioneer in helicopter design and manufacturing founded by American Russian aviator […]