FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1915
1915 - 0253.PDF
APRIL 9. W5- (/yCHT] Edited by V. E. Professcr Langley's Model Work. Continued from page 238). " IN the second trial, which followed directly, it repeated in nearly every respect the actions of the first, except that the direction of its course was different. It ascended again in the face of the wind, afterwards moving steadi'.y and continually in large curves accom panied with a lising motion and a lateral advance. Its motion was, in fact, so steady, that I think a glass of water on its surface _,would have remained unspilled. When the steam gave out again, it repeated for the second time the experience of the first trial when the steam had ceased, and settled gently and easily down. What height it reached at this trial I cannot say, as I was not so favour ably placed as in the first; but I had occasion to notice that this time its course took it over a wooded promontory, and I was relieved of some apprehension in seeing that it was already so high as to pass the tree lops by 20 or 30 ft. It reached the water 1 min. 31 sees, from the time it started, at a measured distance of over 900 ft. from the point at which it rose. " This, however, was by no rr.eans the length of its flight. I estimated from the diameter of the curve described from the number of turns of the propellers as given by the automatic counter, after due allowance for slip, and from other measures, that the actual length of flight on each occasion was over 3,000 ft. It is at least safe to say that each exceeded half an English mile. " From the time and the distance it will be noticed that the velocity was between 20 and 30 miles an hour, in a course which was taking it constantly ' uphill.' I may add that on a previous occasion I have seen a higher velocity attained by the same model when its course was horizontal. I have no desire to enter into detail further than I have done, but I cannot but add that it seems to me that no one who was present on this interesting occasion could have failed to recognise that the practicability of mechanical flight had been demonstrated. " ALEXANDER GRAHAM BELL." Not long after the May experiments Dr. Langley went abroad for needed rest and recreation, and in the autumn [i.e. of 1896], after his return, further experiments were tried. On November 28th a flight was made which was three-quarters of a mile in length, the time occupied being precisely one minute and three quarters. Mr. Frank G. Carpenter was a fortunate witness of this, the longest flight made, and with Dr. Langley's approval he wrote a detailed account of it for the Washington Star of December I2th, 1896. Model No. 5 (1896). " Professor Langley had two successful engined models, No. 5 and No. 6; the former made the flights of May 6th and the latter of November 28th. The weight of No. 5, with fuel and water sufficient for the flights described, was about 30 pounds. The weight of the engine and boiler together was about 7 pounds. The power of the engine under full steam was rather more than 1 horse power. There were two cylinders, each having a diameter of I4 ins. The piston stroke was 2 ins. The two propellers were 39 inf. from tip to tip, and revolved in opposite directions ; the pitch was I "5 ; they were connected to the engines by bevel gears most carefully made, the shafts and gears being so arranged that the synchronous movement of the two propellers was assured. " The boiler was a coil of copper tubing [steel tubing would, of course, have been much better]; the diameter of the coil, externally, was 3 ins. ; the external diameter of the tubing | of an inch. ; the pressure of the steam when the model was in flight varied from 110 to 150 lbs. to the square inch. The flame was produced by the ' aelopile,' a modification of the naphtha ' blow torch' used by plumbers ; the heat of such a flame is about 2,000' F. Four pounds of water were carried at starting and about 10 ounces of naphtha. In action the boiler evaporated about 1 pound of water per minute. The flights could have been greatly lengthened by adding a con denser and using the water over and over again, but the time for that will come later." A few further facts are : the boiler with its firegrate weighed a little over 5 lbs. Total weight of engine (including moving parts) 26 ozs. There was a special pump keeping the water circulating rapidly through the boiler, the intense heat converting some of it into steam as it flowed. [This last statement appears wrongly expressed, the water would not " circulate " in the coils exactly, but be injected or forced in from the reservoir in minute quantities where it would be instantly "flashed" into steam JOHNSON. M.A. superheated and sent into the engines.] The propellers revolved from 800 to 1,000 a minute. The entire model was 15 ft. in length, the wings from lip to tip being about 14 ft. It should be noted that of the total weight, one-fourth, about, was contained in the machinery or power-plant, and that the engine, generator, &c., work out at almut 7 lb. per horse-power. Great advance has, of course, been made since the above narrated experiments were carried out, practically some 19 years ago, loth in the construction of light and powerful steam engines (to say nothing ol the internal combustion engine), and in the designing of model aeroplanes. All this, however, only serves to make Professor Langley's achievements the more remarkable, and they should serve as a most powerful stimulus to all aeromodellists to emulate his example of patient doggedness. Whatever cannot be shown to be scientifically " impossible," must be scientifically " possible," and it is only a question of repealed effort to attain a final and a lasting success. Model Aeroplane Firms at the Agricultural Hall. At the recent Toy I air and Market held at the Royal Agricultural Hall, London, March 16th to 26th, under the auspices of the International Trade Exhibitions, Ltd., only two British firms were represented, viz., the " Birmac" Aeroplane Co., 124, West (ireen Road, Tottenham, N., and Mossrs. C. E. Richardson and Co., Sheffield, who showed a numl>er of " l'inbat " specialities, of which model aeroplanes and kites were only a section. It thus appears that the " liirmac" Aeroplane Co., which showed no other specialities, was the only firm which had a stand devoted entirely to model aeroplane and aeroplane accessories. The head of the company is Mr. lames McBirnie, whose models have been awarded twelve first prizes in open competitions. They are easily distinguished by the special green-coloured silk used for covering the planes, &C. This same company claim to have sold over 800 models in one week at the last Royal Aero Show at Olympia. The excellent flying qualities of these models are well known, and have been often acknowledged, from the Premier's son downwards. The latest model to be placed on the market by the firm is a twin- cylinder rotary-type compressed-air engined model. Whilst congratulating the above firm on its enterprise, one can only ask, why were not more firms represented? Some of them, we believe, were unaware there was an exhibition on. This isn't the way to capture the German trade. From March 14th to 24th, IQl6, Will be held the greatest Trade market ever held in Great Britain. It will take place at the Royal Agricultural Hall and Olympia, amd such additional exhibition buildings as may be necessary. Will British model aeroplane firms and others kindly note, and get ready to fill up a few of those " additional necessary buildings," and not let foreign competitors do it instead ? ® ® ® ® AFFILIATED MODEL CLUBS DIARY AND REPORTS. Club reports of chief work done will be published monthly for the future. Secretaries' reports, to lie included, must reach the Editor on the last Monday in each month. N.E.LondonModelAe.C.(47.JENNKRRD.STOKENEWiNOTON,N.) Monthly Report. — Club meets during the past ihree months, though some what limited by inclement weather, have shown great improvement in the repre sentative flying ; special mention may be made of Messrs. P. Cowderoy, Graham ami Kendall. It is interesting to note that our treasurer Mr. K. Burton has raUed the club duration record to 130 sees. Long&taue has been engaged on C.A. models fitted with an M.S.C. engine and container, and may be seen occupied with frantic pumping on most Saturday afternoons. The secretary will be glad to hear from prospective members ; particulars will be forwarded on application to above address. Haddington and Districts (77. SWINDERBY ROAD, WEMBLEY). Monthly Report*—The weather during the past month has not induced many members to bring out their models. On March 13th, W. E Evans out testing twin-screw pusher canard monoplane. "Ybufuielagc of this model is so constructed that the main plane and the elevator may be set at any desired angles of incidence, the objects of experimentation bting to note the power absorbed by tbc various angles, the rate of climbing, stability, and the gliding angles. The model flew well after a few preliminary trials, maintaining a fairly straight course every time. On March aolh, Carter, Evans, and Woolley out testing manufacturer s models. These consisted of one small single screw pusher canard monoplane, one small tractor monoplane, a larger tractor monoplane, and a tractor biplane. Necessary adjustments were made to some of the models, and improvements suggested with others. Result—some useful work and a capital afternoon's sport. On the J;th, Carter and Woolley flying twin pushers, but a cold north-east wind and snow showers curtailed the amount of work done. The committee hope that all members will join in the two research competitions 253
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
