FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1949
1949 - 1552.PDF
FLIGHT, 8 September 1949 ESSENTIAL SERVICES Developments in the Major Components and Auxiliary Services Fields SO complex a fabrication has the modem aircraft become that the effi-ciency of the whole is no more than the efficiency of the multitude ofcomponent parts. In making any survey of the aviation industry it is, therefore, essential that full value be given to those detail elements without which, in the nature of things, the aircraft as we know it to-day could not exist. Hereunder and on the following pages will be found a review of current developments in the more important auxiliary services fields—a review which, in conjunction with the other features of this issue—the descriptions of aircraft and engines, and the trade directory—combines to give a comprehensive picture of the British Aviation Industry. Stand numbers at the S.B.A.C. Show are included. »• AIRSCREWS The Airscrew Co., Ltd., Weybridge,Surrey, are one of the oldest British airscrew-building concerns and havealways specialized in wooden construc- tion. In addition to fixed-pitch woodenairscrews for light aircraft, they also pro- duce " Weybridge" blades for incor-poration with controllable-pitch hubs made by other companies. Anotherspeciality of this concern is the manufac- ture of specialized fans for wind tunnels;windmills for target-towing aircraft winches and recirculating ducted fans forcabin atmosphere control installations. De Havilland Propellers, Ltd., Hat-field, Herts (Stand 93) make airscrews suitable for engines of from 100 h.p. toover 4,000 h.p. From small, manually operated types of simple construction tothe highly developed, constant-speed, feathering and braking types, the deHavilland range of airscrews include two-, three- and four-blade single rotat-ing, and -six-blade contra-rotating -de- signs. For some time, now, the Com-*pany has been paying attention to the development of airscrews for turboproppower units, recent installations having included the Athena, Balliol, Apollo, and the forthcoming S.R. 45 Princess andTheseus-Hermes V. The Fairey Aviation Co., Ltd. (Pro-peller Division), Hayes, Middlesex (Stand D), continue to produce the dis-tinctive twisted-metal-blade airscrews which were initiated a good many yearsago. Fixed-pitch, two-blade types are available for a range of powers approxi-mately from 100 to 500 h.p. for use with British engines as well as various Ameri-can and European engines in this power category. The company have recentlyreceived an order for 500 airscrews for use with the British-built de HavillandChipmunk, and, in addition to current developments with variable-pitch ver-sions of the smaller airscrews, strain- gauge flight testing is also in hand on thelarge, four-blade, electric, constant-speed, feathering and braking airscrew intendedfor turboprop installations in the 2,000- 2,500 h.p. class. Hordern-Richmond, Ltd., Haddenham, Bucks (Stand 51), have recently con- cluded an agreement for manufacture and sales rights of the Aeromatic airscrew —the F.200 for engines of 65 to 150 b.h.p. and the F.220 for 155 to 330 b.h.p. In addition to these, the company also Above : The latest Rotol airscrew is for No. I size shafts for engines of 180-250 h.p., and combines the governor unit with the airscrew hub. Below: Investigating vibration amplitudes and frequencies on an experimental swept-back blade in the Vibration Department of de Havilland Propellers, Ltd. manufacture compressed wood blades foruse with controllable-pitch hubs and, in fact, have supplied the blades for theRotol hubs employed on the prototype Brabazon I. Main rotor blade spars andcomplete tail rotors for the Bristol 171 helicopter are another Hordern-Richmondproduct, as are the tail rotors fitted to the Westland-Sikorsky helicopter. Jablo Propellers, Lid., Waddon,Surrey (Stand 145), specialize in the construction of detachable wooden bladesdesigned for power absorptions between 200 and 2,000 b.h.p. One of the com-pany's more interesting developments is a composite wood and metal laminatedblade in which the shear value of the root-end threads is increased so enablingthe root diameter to be reduced. If necessary, the metal laminae can be ex-tended throughput- the blade to permit a reduction in section thickness. Rotol, Ltd., Cheltenham Road,Gloucester (Stand 82), have attained world renown as manufacturers of air-screws, their range covering power cate- gories of from 150 to 7,000 b.h.p.Turboprop requirements have emphas- ized airscrew blade aerodynamic effi-ciency and, to this end, the company have developed a composite blade,wherein electric de-icing elements are fitted inside a hollow metal leading-edgeattached to the basic dural blade. Auto- matically withdrawable pitch-locks havealso been developed for turboprop air- screws for engine-starting and negative-thrust braking purposes and, in addition, for the further development of a specialwindmill brake pitch for airscrews of dive-bomber aircraft. Synchronizationequipment is another Rotol development, < IB I IN -ATMOSPHERE CONTROL Artif-Ice Products, Ltd., 176, Have-lock Road, Brighton, Sussex, are manu- facturers of the " Chemicooler," a com-pact little unit about the size of a small radio set, by means of which air in, forexample, the cabins of the smaller air- craft types up to feeder-liner size can becooled. A charge of about 9 lb of solid CO2 is placed in the container built intothe unit, airflow through the unit and across an array of coottng tubes beieggenerated by a small electric fan. D. A. Darilel & Co., Ltd., Machynl-lelh. North Wales Stand 148), use the trade name "Dragonfly" for their sur-face combustion-heaters. The company have recently completed an extensivedevelopment programme and now have in production a range of heaters withcapacities of from 50,000 to 400,000 B.T.U./hr, together with manual orautomatic temperature control, the latter on the basis of an inching device operat-ing from a temperature-sensitive phial as well as thermonic controllers in whichthe inching characteristic is inherent. Below : Additional safety is provided by the latest Normalair dupli- cated pressure controller in which are embodied two standard high- pressure master control units.
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
