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WASHINGTON, Dec. 26 (Xinhua) -- U.S. top-tier aircraft manufacturers Lockheed Martin and Boeing on Wednesday revealed a newly designed helicopter which could travel twice as fast as conventional ones.

Lockheed Martin, the builder of F-35 and F-22 stealth fighter jets, announced that its subsidiary Sikorsky and aircraft maker Boeing provided the first look of their "Defiant" helicopter, which was developed as the U.S. Army's next-generation military helicopter.

According to the announcement from Boeing and Lockheed Martin, the "Defiant" was designed to fly "at twice the speed and range of today's conventional helicopters" and offered "advanced agility and maneuverability."

The most highlighted feature of the new helicopter is its "pusher propeller," which sits at the aircraft's tail and generates direct thrust to push itself forward. Although such design has been widely used on ships, it could help the aircraft to break the speed limit of traditional helicopters.

Besides, the new design puts two sets of rotor blades at the top of the helicopter. One set of blades is mounted above the other set with the same axis of rotation, while each of them turns in opposite directions.

According to Lockheed Martin, the helicopter would include four crews on board for the operation of the aircraft, while transporting 12 combat-equipped troops in the cabin.

Boeing and Lockheed Martin both said the new helicopter was expected to enter service in the early 2030s.