Japan Today

NASA's Mars helicopter achieves 1st powered flight by an aircraft on another planet

To accomplish all this, the helicopter’s twin, counter-rotating rotor blades needed to spin at 2,500 revolutions per minute — five times faster than on Earth. With an atmosphere just 1% the density of ...
GIGAZINE

Helicopter "S-97 RAIDER" capable of high-speed flight with thrust of a counter-rotating ...

It is an American helicopter manufacturing company and also manufactures military aircraftSikorsky · AircraftOf the new type helicopter "S-97 RAIDER" which the company has been developingConcept ...