FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1909
1909 - 0512.PDF
AUGUST 21, 1909. CORRESPONDENCE. *#* The name and address of the writer (not necessarily for •publication) MUST in all cases accompany letters intended fot insertion, or containing queries. RE PROPELLER TEST. To the Editor of FLIGHT. SIR,—I read with some interest your report in FLIGHT of the trial of Mr. Cochrane's propeller against the Beedle propeller. The conclusion that one might arrive at in reading this report must to a great extent be unsatisfactory. It will be observed that per electrical h.p., our propeller was far and away the better of the two, although the weight of the propeller was greater, but surely a few ounces, or lbs., that one propeller may weigh more than another is quite insignificant in comparison with the h.p. required to drive it, and therefore the weight of the motor. I am glad to say that we have received instructions from M. Bleriot to make a propeller for the aeroplane that he is now constructing, and we think that it will be far better to have a demonstration of a larger diameter propeller, a propeller, in fact, that would be of some use in aviation, rather than to testa series of toys. Yours faithfully, HENRY j. ROGERS, WATFORD ENGINEERING WORKS. ANOTHER PROPELLER CHALLENGE. To the Editor of FLIGHT. SIR,—Referring to my recent letters conveying the above, although I singled out Mr. Handley Page (the favour of whose further reply I await), I now desire to extend my challenge to all comers with large propellers. In continuation of my letter of last week, I would say to Mr. H. Page, that if the carrying capacity of the aeroplane selected admits of it, I will accompany the pilot on the trial flights. Yours faithfully, SIDNEY H. HOLLANDS. To the Editor of FLIGHT. SIR,—We note that Mr. Sidney Hollands does not wish to enter twin propellers, and therefore the machines upon which we gave him the option of fitting two of his propellers will be of no use to him. We have much pleasure in saying that we shall be able to have the competitive trial with a tractor screw upon a monoplane, but we are afraid that it will be another three or four weeks before the first of our monoplanes will be ready for its trials. Yours faithfully, HANDLEY PAGE, LTD., HANDLEY PAGE, Managing Director. To the Editor of FLIGHT. SIR,—If Mr. Cochrane's challenge re model propellers still holds good, I should like to arrange to test my propeller against his at the earliest convenience. Yours faithfully, Shepherd's Bush. L. TURNER. STILL WANTED: A CLOCK-WORK MOTOR. To the Editor of FLIGHT. SIR,—Many thanks for sketch and reply to my letter recently published in FLIGHT, the points I raised are now quite clear to me. What a blessing it would be to amateur models makers if some enterprising firm could bring out a light clockwork motor at a reasonable price. I am now on the look-out for something of this sort to drive my models, but have heard nothing up to the present. Should you know of one I should be extremely obliged if you will give me the name and address of the makers. Thanking you in anticipation, Yours faithfully, Huddersfield. VIVIAN B. LEAROYD. THE CENTRE OF GRAVITY. To the Editor of FLIGHT. SIR,—In your issue of August 7th you mention the fact of the centre of gravity of the Plazzeriaud triplane being place very low, and as to opinions differing on the advantage of this principle. Perhaps a few remarks as to my experience in this direction may do no harm. In the machines I refer to, the centre of gravity was kept very much lower than is the case with any present successful aero- plane, the surfaces being superposed, arid it was thought this would be an advantage, but it was proved conclusively that the fart of placing the centre of gravity low was not of itself sufficient to ensure lateral stability, except in a calm or when the machine was dead head to wind. The cause of the trouble was this, that in flying across the wind as each gust struck the machine the lower heavier part was less easily deflected from its course than was the upper lighter part, consequently the machine heeled over to leeward. In addition to this, the end of the sustainness to windward being momentarily more affective as regards lift, the machine was practically blown over before you knew where you were and before the centre of gravity had had time to assert itself. It was the same in turning ; if too short a radius was attempted the lower part would swing out, and allow the inner end of the surface to come in contact with the ground, the flights being carried out low down. I should mention that no means of warping the surfaces were provided. The remedy would appear to consist in arranging a sufficient area of fore-and-aft surface below the centre of gravity, making a keel, as it were ; the effect of this would be that the whole machine would be blown to leeward on an even keel, and if the centre of pressure of this surface or surfaces was arranged to come behind the centre of gravity, it would have the effect of tending to bring the machine head to wind, therefore, keeping it up to its course. Of course, a vertical rudder placed aft tends to do the same things. 1 certainly do not believe in fitting a vertical rudder in front. 1 should anticipate no practical difficulties as regards control with a machine such as I have endeavoured to describe. All the trouble that I have seen in this direction has been caused through the machine having lateral motion in regard to the air it was passing through, whether caused by the rudder or the varying speed of the atmosphere. Therefore the solution of the problem, if such it is, of obtaining automatic lateral stability appears to consist in providing such an area of vertical surface as to practically make the machine incapable of any lateral motion as regards the air it is passim; through, such surfaces correctly distributed in conjunction with a low centre of gravity should go far in keeping the machine on its feet, as it were. Yours truly, Shepherd's Bush. F. H. PHILLIPS. [Correspondence and other matters have again to be held over.—ED.] ® ® ® ® NEW COMPANIES REGISTERED. C. W. Agency, Ltd.—Capital ^500, in £\ shares. Dealers in motors of all kinds, cycles, boats, flying machines, &c. Planes, Ltd.—Capital ,£10,000, in £\ shares. Aeroplane, balloon, kite, parachute, flying machine, and aquaplane boat and ship builders, &c. © o 0 e Aeronautical Patents Published. Applied tor in 1008. Published August igth, 1909. 15,924, T. G. K. CLARKE. Aeronautical machines. 16.153. F. WOOD. Aerial machines. BACK NUMBERS OF FLIGHT." THE publishers have pleasure in announcing that they have secured a few of the back issues of FLIGHT, and any of our new readers who may wish to complete their sets may obtain the first thirty-three numbers for 5*. od. (abroad ys. gd.) post free, from the Publishers, 44, St. Martin's Lane, W.C. FLIGHT. 44, ST. MARTIN'S LANE. LONDON, W.C. Telegraphic address : Truditur, London. Telephone: i828Gerrard. SUBSCRIPTION RATES. FLIGHT will de/orwarded, post free, to any part of the world at the following rates: — UNITED KINGDOM. ABROAD. d. 3 Months, Post Free 6 ,, ,, 12 „ s. a. s. d. 1 8 3 Months, Post Free... 2 6 3 3 6,, „ ...50 6 6 12 „ „ ... 10 o Cheques and Post Office Orders should be made payable to the Proprietors of FLIGHT, 44, St. Martin's Lane, W.C., and crossed London and County Bank ; otherwise no responsibility will be accepted. Should any difficulty be experienced in procuring FLIGHT from local newsvendors, intending readers can obtain each issue direct from the Publishing Office, by forwarding remittance as above. 514
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
