Up to $5 million could be set aside to study unusual heavylift rotorcraft design

The US Army plans further investigation of an unusual heavylift rotorcraft design using up to $5 million in funds earmarked by Congress for work on the Mono Tilt Rotor (MTR) concept developed by New York-based Baldwin Technology (BTC).

The MTR combines a coaxial rotor with a folding wing, lightweight airframe and a cargo container handling system. A conceptual design study completed in December last year, with funding from the US Office of Naval Research, concluded the MTR could carry a 20t load an "unprecedented" 1,850km (1,000nm) at a cruise speed of 200-250kt (370-460km/h).

The cargo container is suspended from the gearbox, and hangs directly below the rotor in vertical flight, or helicopter mode. The pivoting twin-boom tail is pinned parallel with the suspension structure to increase its strength and stability, and the wing is folded to minimise downforce from the rotor.

As the MTR accelerates in forward flight, while still in helicopter mode, aerodynamic forces lift the tail and unfold the wing. Once the tail and wing are locked in place, the rotor tilts forward to become a contra-rotating propeller and the vehicle transitions to fixed-wing, or aeroplane mode, for the cruise.

Fairings and aerodynamic surfaces attached to the cargo container reduce drag and stabilise the suspended load in forward flight. Fuel is carried close to the dynamic system and engines, below the rotor, while the crew compartment – if required – is located at the bottom of the suspension system, above the payload.

BTC founder Doug Baldwin says he will release more details of his concept and plans after receipt of the initial $850,000 contract from the US Army's Aviation Applied Technology Directorate.


Source: Flight International