FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1944
1944 - 0096.PDF
5o , FLIGHT JANUARY I3TH, 1944 CORRESPONDENCE The Editor does not hold himself responsible jor Ike views expressed by correspondents. The names and addresses of the writers, not necessarily for publication, must in all cases accompany letters. r</ JET PROPULSION "Flight's" Faith is Vindicated THIS must be a great day for you. The advocator of a system against great opposition and now—the whole world greet ing jet propulsion as an achievement and a reality. My heartiest congratulations. Having conquered this field, what are you going to turn your hand to next ? H. L. R. THEORY OF FLIGHT Dumping Process Worsens L\D Ratio HAVING followed the "Dump or No Dump" controversy in your Correspondence columns with some degree of in terest, it does not seem to have occurred to anyone that before a condition of lightened weight can be achieved, something has got to be pitched overboard, and this can only mean opened hatches and increased resistance. Even a column of liquid fuel leaving the aircraft can hardly be expected to increase the aerodynamic efficiency, all of which must result in a worsened L/D ratio for the whole period of time occupied in the jettison ing operation. This condition can only be balanced by a coarsened gliding angle. Obviously, with the jettisoning completed, the aircraft will revert to its original order of L/D and angle of glide, and with out going into the question of speeds and distance, its flight path will have become stepped down to an extent which would probably negative any gain that jettisoning might promise. S. H. BOSTOCK. BRISTOL TORPEDO Development of the Bellows Flap MY attention has been drawn to the September 2nd issue of your journal (page 253) describing a "bellows flap" on the Beaufighter torpedo plane manufactured by the Bristol Co. The type of flap fitted to the Beaufighter is known as the " Youngman bellows flap," and was first proposed by me some seven years ago and later developed by me full scale as an airbrake under the auspices of the Fairey Aviation Co. At the suggestion of the Ministry of Aircraft Production the in stallation on the Beaufighter followed this development work under my direction and introduces nothing new in the method of operation. The development work done by the Bristol Co. was confined to the application of the bellows flap to the particular needs of the Beaufighter, such as the best disposition of the flaps on the wing to avoid sudden changes in lift, pitching moment, and the avoidance of tail buffeting. R. T. YOUNGMAN. BOMBER ARMAMENT Muzzle h.p. the Only Fair Test I HAVE read Robert Chorlton's letter of December 16th, and should like to occupy your valuable space once more on an important subject. Whether air-gunners worry about it or not, the fact remains ( mv^r \ lis the only fair test of a gun's merit. It takes all factors into account—mass, velocity and rate of fire. The instalment of 0.5U1. and 20 mm. guns in fighters (which fight much more split-second actions than bombers) shows that the strikes per sec. of the 0.5m. (12.5) and of the 20 mm. (10.8) are more than adequate. The question of additional weight should not deter anyone from installing higher-calibre guns. Bigger aircraft (with more h.p.) and/or fewer guns is the answer, e.g., as in the Typhoon IB, successor to the Hurricane I; the Spitfire Vc, successor to the Spitfire I, and the Hurricane He, successor to the I. We must progress and plan ahead. That is why the Ameri cans have a temporary advantage. "YOUNG SPOTTER." THE CASE FOR THE FLYING BOAT Why Not Amphibian? AFTER reading the two articles in Flight concerning flying boats in the post-war years, the Saunders Roe report, and C. A. H. Pollitt's article, "Where Angels Fear . ..." a possible compromise occurred to me—if ft were necessary, considering the large percentage of converted military aircraft which will obviously be used for transport in these years. However, for discussion's sake, the obvious solution would appear to be the amphibian. Even though I, too, may be "rushing in, etc.," knowing only a limited amount of aircraft construction difficulties as I do. I have heard many derogative remarks passed about the amphibian—"Elephantine," etc.— but I would beg to recall one very successful example to such sceptics—the inimitable "Walrus." Not as an aerodynamic criterion, but as an example of good and successful service. Admittably, it was rather a stringbag, and, as far as I know, no very aerodynamically good amphibian has yet been built, but why should it not be possible to improve ? One could envisage a four-engined aircraft (or larger, should any of the more optimistic futurists wish it) with a similar general layout to the Boeing Clipper type, the stub-wing beinj*- necessary for efficiency. This would afford the necessary mounting for a fairly wide wheel base without the extra weight entailed in a high-wing retractable wheel layout. The main wheels would not have to have very long legs either, thus eliminating complications and unnecessary weight to a mini mum. Generally, the undercarriage would be tricycle, the nose wheel retracting backwards into a watertight compartment, and well-constructed well-doors providing a good planing surface, together with a certain watertightness to protect the wheel itself. The main wheels would retract inwards into simi larly constructed wells. The comparatively low clearance neces sary would allow the main wheel legs to be short, and therefore it would be unnecessary to tamper with the chines, the stub wing being sufficient to carry the retracted wheels. The stub wing would, of course, have to be set fairly far back in order to provide a long wheel base and prevent '' nosing over.'' The advantages of such an aircraft would be many, and even the flying boat seems very desirable in any post-war planning. There is no necessity to enumerate the various advantages of the flying boat over the land plane, as they are admirably set out in the Saunders Roe report. Mr. Pollitt has only given yyo points to back his theory that there will be no place for fly**" boats. They are, admittedly, good points, but I believe that one of them, at any rate, could be eliminated by the amphibian —that the flying boat only provides coast to coast service. To quote Mr. Pollitt's own case, such an amphibian as I have described above could take off from Birmingham for Southampton, possibly carrying extra pay-load for the short distance, landing there, refuelling and flying, either straight to Jo'burg, or to Durban, and repeating the process. One amphibian would also eliminate the necessity of a float ing dock for servicing, as, obviously, it could be run up into a hangar at a sea terminal, if necessary, without any difficulty, merely by the construction of a concrete ramp. In any case, it could be serviced at a land terminal. Even should a floating dock be necessary (for a flying boat), it seems that a simpler method would be to provide a longer overhead system, and provide retractable servicing platforms for all engines, without the necessity of extensible platforms for the outboard engines. Another point in favour of the flying boat which is often forgotten is the safety factor. Should an aircraft have to " force- land " on the sea, a flying boat has the obvious advantage, and an amphibian has the further advantage of being able to " force-land" on both sea and land (depending, of course, on whether the sea or land is smooth enough). Furthermore, there is the not inconsiderable psychological effect on any inexperienced passengers—and there will be many in the imme diate post-war years. Obviously, the first thing that would occur to a "first-time passenger" when flying over the sea would be '' What happens when we come down ? '' and the feeling of security provided by a hull would be obviously con siderable. Not the sort of thing that would effect post-war planning—or is it ? While on the subject of flying boats, it occurred to me that if the pay-load loss due to chines and steps were 3 per cent. , and the pay-load gain due to the elimination of undercarts were 3 per cent., doesn't one cancel . . . ? P. J. EDMUNDS.
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
