Keywords
Citation
(1999), "Tail rotorless helicopters", Aircraft Engineering and Aerospace Technology, Vol. 71 No. 1. https://doi.org/10.1108/aeat.1999.12771aad.004
Publisher
:Emerald Group Publishing Limited
Copyright © 1999, MCB UP Limited
Tail rotorless helicopters
Tail rotorless helicopters
Keywords Helicopters, Patents
In GB Patent 2320477 Rolls-Royce plc describes a helicopter which has a main body portion, a main rotor, a gas turbine engine, including a variable area exhaust nozzle for driving the main rotor, and a hollow tail boom extending from the main body portion. Exhaust efflux from the engine is directed into the boom and the boom is provided at an end remote from the main body portion with a means for directing exhaust efflux from within the boom into the atmosphere at an angle that may be controlled with respect to the axis of the boom. The means is arranged in a first mode of operation to direct the efflux sideways from the boom so as to provide anti-torque, and in a second mode of operation is arranged to direct the efflux rearwards in the direction of the axis of the boom so as to provide forward thrust. The tail boom may have an aerofoil cross section which interacts with the main rotor downwash to supplement the side thrust.