Power Plant System for V/S.T.O.L Aircraft: The Rolls‐Royce Philosophy as It Applies to Special Lightweight Lift Engines and Deflected Thrust Propulsion Engines and Their Suitability for a Variety of Roles

THE Society of Automotive Engineers' paper, upon which this article is based, followed very closely along the lines of an article entitled ‘Composite Power Plant System for V/S.T.O.L. Aircraft’ published in the December, 1962, issue of AIRCRAFT ENGINEERING [see Ref. (4)]—although the latter paper concentrated upon a description of the RB. 162 and the use of lightweight lift engines for a V/S.T.O.L. low‐level strike fighter. The S.A.E. paper has therefore been slightly condensed here, to avoid unnecessary duplication and a number of illustrations have been omitted. Throughout this paper there are references to the advantages of a multi‐engined aircraft for the V/S.T.O.L. fighter application in preference to the single‐engined type. These passages must be read in the light of the recent statement to the effect that Rolls‐Royce have submitted to the Ministry of Aviation design proposals for a version of the Hawker PA 154 V.T.O.L. aircraft powered by two lift/thrust engines based upon the Spey by‐pass engine. These two lift (thrust engines would replace the single Bristol Siddeley BS.100 vectored thrust engine which is believed to have a thrust (with plenum chamber burning) of about 30,000 lb. Apart from the more obvious advantage of having two engines, i.e. safety, and the ability of the aircraft to complete the mission as a conventional aircraft if one engine fails, there is also the additional and attractive proposition that the Rolls‐Royce Spey engine is already in quantity production for a number of civil and military aircraft and could presumably be readily adapted to a lift/thrust configuration with front nozzle incorporating plenum chamber burning and rear nozzle. Finally, the reader is recommended to study in full the articles referred to in Refs. (2), (3), (4) and (5), in addition to this paper, since these provide a comprehensive survey of the jet lift field and in particular the application of jet lift to V/S.T.O.L. fighters. The six references listed on this page did not, of course, form part of the original S.A.E. paper—Editor.