FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1910
1910 - 0421.PDF
MAY 28, 1910. celebration on Governor's Island, New York, and Mr. Jack Humphreys used a boat-shaped hull on his first machine with a view to starting on water. The following note (N. 126) appears in " Flight Manual" :— " The use of a lake is sometimes contemplated as an aerodrome, the flyer being fitted with suitable floats instead of either wheels or runners. It must be borne in mind, however, that the speeds which obtain in flight are for the most part in excess of those which have yet been achieved on water."—ED.] SINGLE-SURFACED PLANES. [537] With regard to single-surfaced planes (490), with the exception of the Curtiss machine the ribs are screwed to the top side of the front main spar and the under side of the rear spar, leaving the under side smooth. The Curtiss has the ribs on the top of both spars, which does not leave a smooth under surface. Belfast. LILIAN E. BLAND. LOADING OF GLIDERS. [538] Tne following might interest W. Smith (487) with regard to weight carried per sq. ft. in gliders :— lbs. per sq. ft. Pilcher glider Montgomery glider ... Lilienthal biplane glider Wright gliders... Lilienthal monoplane glider The Mayfly 7 ro8 I-18 I -2 and 1-3 2-l 2-o in winds of 20 m.p.h. A well-designed biplane glider should certainly lift t 5 lbs. per sq. ft. in a steady bieeze of 15 m.p.h., but, of course, the lift depends on the proper plane camber, which should be about 3 ins. for a chord of 5 ft. about 20 inches from the leading edge, or less, and in my machine the main spars have a negative and positive angle. LILIAN E. BLAND. AUTOMATIC ADJUSTMENTS. [539] I would suggest the following plan for keeping flying machines at a fixed altitude. I would place a light fan so that it would revolve parallel to the earth in the centre of a short vertical tube, funnel shaped at each end. This fan would depend on currents of air blowing up or down the funnel-shaped tube to revolve it. Now, any downward movement on the part of the machine would cause an upward current in the tube and revolve the fan. which, through the gear, would adjust the elevator to a greater lifting angle, thus counteracting the downward movement of the machine, and any upward movement on the part of the machine would cause a downward current in the tube, and revolve the fan in the opposite direction, thereby adjusting the elevator to a lesser lifting angle. I would have the machine kept in a straight course by a similar fan, suitably placed, working the rudder. The fan in this case would be placed so that a movement of the machine from right to left would revolve the fan one way, and any movement of the machine from left to right would revolve the fan the reverse way. The short funnel tube in this case would be placed parallel to the earth, and across the aeroplane I would have a shield placed so that it would revolve round and cover either end of the tube, to protect it from the wind, as it is necessary that the fan should not revolve in proportion to the velocity of the wind, tending to drive the machine out of its true course, but in proportion to drift of machine to either side. I hope your readers will understand the above description. Space will not permit me to go into details of the plan. Dublin. JAMES J. MCGRATH. [It seems to us quite impossible that the system advocated in the above letter would be likely to answer in practice, firstly, on account of the difficulty of eliminating the effect of aerial disturbances in the tubes, caused by air passing across the orifice, and, secondly, owing to the time lag that would be introduced by the inertia of the mechanism.—ED.] ARCHED WINGS. [540] Re Mr. F. C. Harrop's letter (No. 460) in FLIGHT of April 16th, I am very pleased to find that he has apparently arrived at the same type of wing as I have. Some months ago I made a small glider with the dropping wing-tip, and found it almost uncap- sizable: The principle is the same as the turned-up wing-tip, but a very little thought as well as experiment will show its superiority over the latter type. The action is the same as the dipping front edge and not only increases stability, but is almost totally unaffected by wind-gusts. The idea, as far as I can gather, is adopted on Capt. Sanders' biplane. Hatfield. J- McC. CLIVE. l/ycfiTj MODELS. PAPER MODELS. [541] I enclose herewith a sketch of a little paper model mono plane that I have found to be very satisfactory in use and very simple iTOMP SIDE ELEVATION to construct. Possibly it may be of interest to some of your readers who are fond of experimenting with such devices. The wings have a dihedral angle and pointed extremities. •Whitby. L. MELLOR. SERRATED CUTTING EDGE. [542] With reference to Mr. W. P. Dean's suggestion in March 5th (395), re serrated cutting edge, it seems to me that the advantages he maintains for it do not hold in a single case, except, perhaps, the flexibility. The area of the plane is exactly the same as if it were plain rectangular / x b, for the spaces, sss, may be exactly filled by the protuberances, PPP. Consequently, area for area, the overall length is the same. The actual cutting edge is much longer than the overall length, and, as it occupies the same frontage, it cannot afford less resistance than a straight cutting edge. _ Then, again, a complication may be introduced in this way: Let cd and ef be two adjacent sectional elevations (see plan). Now, the stream lines of the wind under the plane follow the curvature ; therefore, there is bound to be friction between two streams of air travelling under adjacent strips of the plane. Hoping for an elucidating explanation of these points from Mr. Dean. LeerJs. A. WOODMANSEY. BIPLANE V. MONOPLANE FOR MODELS. [S43J Much time and patience is being devoted to the construc tion of models by the industrious readers of FLIGHT, and I should advise them to try building a monoplane before launching forth on a biplane, as the former is so extremely simple to construct that any one might build one. All that is necessary is to construct an A- shaped chassis, attach the wheels or ski, then fix the two planes and the body which carries the tail and elastic, and you have a good little flyer ; but the biplane requires more patience and cash- though I prefer the latter. I admire the plucky manner in which Miss Bland attacks the problems of flight, and the way in which she aids her contempo- 419
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
