FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1945
1945 - 1465.PDF
IO2 FLIGHT JULY 26TH, 1945 CORRESPONDENCE The Editor does not hold himself responsible for the views expressed by correspondents. The names and addresses of the writers, not necessarily for publication, must in all cases accompany letters. TRANSATLANTIC SERVICES Surely More Than a Sideline? YOUR comment on the news that Pan American, AmericanExport Airlines and T.W.A. are to operate air services on the North Atlantic is that. '' on this side of the Atlantic weshall have a single corporation ... to which the route to the USA., is but a sideline." It this is so, then is it not possible that Pan American'sAtlantic Division will be equally a sideline to its main and extensive undertakings, existing and planned, to LatinAmerica the Far East, Australia and South Africa; and the Atlantic routes of the other two companies will be " sidelines "to their existing routes? Whether one agrees or not with the recent White Paper onthe administration of B.O.A.C., we should do well not to under-estimate the calibre of bur British merchant airmen.They have, all the year round, maintained and developed services to Africa, India, Australia and elsewhere. B.O.A.C.pilots established the first Atlantic service to fly winter and summer. For two winters they were alone on the route.To-day they are flying eleven Atlantic services a week in both direction? Surely this is something more than a sideline?E. LINDSAY SHANKLAND. POST-WAR AIRCRAFT INDUSTRY " Britons Only," a Myopic PolicyM R. PRATLEY hopes "that all concerned (in the Britishaircraft industry) will undertake to employ only British men and women, thus making as great a contribution to thepeace as they made to the war" (Flight, July 19th). If all concerned adopt such a myopic policy, then so farfrom promoting peace they will foment war. Employment should depend upon merit. Those British men and womenwith merit have nothing to worry about, but I do not see why a foreigner should not be employed before a British manor woman if the foreigner offers his services, is highly capable, and if the British man or woman is unskilled. An extreme case of particularism would be if the Lancashiremills refused to employ a Yorkshireman just because he came from a different county.Let the British aircraft industry have the best brains and hands available, give those brains and hands the best machines,and then the industry can give to Britain the finest aircraft in the world. M. T. MOORE. MOORING FLYING-BOATS A Field for Special Development I HAVE read with interest the particulars and correspondencerecently published on the subject of progressive methods ol facilitating the loading and unloading of the giant flying-boats of the future. Might I venture to suggest that some attention might be given to the development of methods thatwould enable these large aircraft to be moored or '' tied up'' alongside surface ships in reasonably calm waters. This mooring facility would be a great advantage as it wouldallow direct transfer of goods, fuel, passengers and crew, as well as enabling repairs to motors, etc., to be done rapidlyand conveniently. The system would involve special " fending-off" devicesand new warping methods. It might also be applied in some cases to piers and jetties. W. ADAM WOODWARD. AIRCRAFT NOISE Sudden Selection of Fine Pitch YOUR correspondent D. R. Campbell asks for an explana-tion of the Harvard "roar" and also for the drop in airspeed (Flight, June 21st). The explanation is very simple and quite logical, namely,that the pilot is probably cruising at about 1,700-1,750 r.p.m. with, say, boost set at 27 to 30 hg. He then swiftly selects" full fine" pitch and the r.p.m. will momentarily reach 2,300 to 2,350 and then settle at approximately 2,250 as the c.s.u.regains control. The Harvard engine is attached directly to the airscrew shaft so that the Hamilton constant-speed propellerwill also turn at 2.250 r.p.m. or upwards. The earsplitting roar is caused by the airscrew itself, which will have anenormously high "tip speed " at such r.p.m. The drop in air speed is very noticeable when a suddenselection of full fine pitch is made and the pilot can be thrown sharply forward if his straps are loose. This trick can be used to advantage when overshootingwhilst in formation, but, of course, the pilot selects "throttle closed" first. The Spitfire V is also apt to lose speed veryquickly if the throttle is '' chopped,'' and a quick selection of full fine pitch is made. This trick, however, will not workat all with a Tempest V aircraft. Perhaps someone can explain why it won't. I suggest that W. R. Campbell's " roar " is nothing moreor less than a "particular pilot technique." •"DICER." Blade-tips Whip at High Revs T AM writing a few lines in answer to a reader's complaint oi JJ -»- the earsplitting Harvard roar published in Flight, June* 2ISt. ^ I have worked on many types _ of high-powered aircraft engines, and this noise, as you know, is not experienced. But the Harvard, Reliant and others fitted with Pratt'and Whitney Junior engines or Lycoming engines of the lower-powered type —namely, 450 to 650 h.p.—are not fitted with a reduction gear; the propeller is driven at crankshaft speed. This causes the tips of the blades to whip at high engine revs., as the tip speed is around the speed of sound, thus causing the "roar." It is only experienced when the pilot selects positive fine pitch, i.e., maximum r.p.m. for landings and take-off, Or any other time the pilot selects maximum power. I have tried to get more information about this, but I am afraid nobody seems to know definitely. They do not, how- ever, condemn my theory. S. FIELD. EXPENSIVE SPEED A Category Already Catered For TO what useful purpose does your correspondent, DouglasDeans (Flight, July 12th), really wish his proposed society to direct aviation ? He cannot have read many of the latestspecifications at all deeply, or he would have realised that the sole purpose in every new civil transport design is to carry the maximum volume of payload—passengers or freight as economically as possible on the specific routes for which thedesign is intended. Mr. Deans appears to be mainly interested in cheap week-ends on the Continent, a highly competitive field of transport. He admits that in face of good surface transport facilities, airtravel which is slow is useless. Why, then, should he expect operators to run a service at a loss because he is not prepared .to pay for the speed which is the aircraft's only raison d'Stfi-^Sli this field? He asks why aircraft must always travel six or"*seven times as fast as ships when they have only ships to com- pete with. Surely the anwer is that nobody wants to spendmore than one day on a non-stop flight over a route which is normally six or seven days' travel by rail and sea. He has plenty of scorn for the designers of the '' bigger andfaster" aircraft and the " gadgetry " associated with them. Can he tell us how he would set r-.bout designing a trans-atlantic airliner with full sleeping, cooking, sanitation and recreation facilities for even twenty passengers if the trip wereto extend on a very moderate comfort level over three days instead of 12 to 15 hours ? I fancy he would need well over500 h.p. per passenger to combat the adverse weather risks which would be six times more likely to be met. Could heprovide reasonable sound insulation, ventilation, ice-preven- tion and stability without the '' gadgetry '' he despises ? Ofcourse not, and he is wasting his time if he attempts to apply the Tudor and Brabazon I specifications to aircraft required forshort routes like Renfrew to the Hebrides, which are in another category and well catered for. " One specification at least seems to have slipped his memorycompletely, for where could he find a modern aircraft less encumbered with "gadgetry" than the Bristol 170? He has _no need to enlist support for his society. It has been in exist- ence for many years, and its membership is mainly composedof our despised designers who know not only exactly what they want, but how useless it is to argue with uninformed armchaircritics who cannot assimilate even the daily news that is spoon- fed at their breakfast tables. SENRAB.
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
