FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1935
1935 - 0956.PDF
t> FLIGHT. APRIL 25, 1935. - FLYING FLATFISH The " All-wing " Aeroplane : Some Interesting Foreign Departures from Conventional Design AFTER many years of worship of the aspect ratio goddess, there is a ^ noticeable tendency in several coun tries to depart from this ideal and go almost to the other extreme of using a wing which is flying " end on," or, more cor rectly, "corner on." Two excellent ex amples have just appeared, one in America and the other in Italy. Although it is unslotted, and napless into the bargain, the American Hoffman two- seater monoplane, which employs a wing of exceptionally low aspect ratio, is claimed to possess a speed range of 30 to 135 m.p.h.—and that on the power of an 85 h.p. engine and when using a fixed under carriage ! The span is only 22ft. bin. and the maximum chord as much as 14ft. 6in., giving an area of 237 sq. ft. Welded-steel tubing is employed for the centre section, fin and rudder, the remainder of the machine being of spruce. Three spars are used for the wing, with double-drag trussing in each bay. The centre spar is twenty inches deep and the wing sections are of the M6 type, with Mi at the tip and ex tended M6 at the centre. There are two elevators, with push-and-pull connections, and the "tip" ailerons are operated with a torque tube. Two stabilisers are mounted outboard of the elevators, which, it would appear, are adjustable over a range of incidence. A retractable undercarriage has been specified for the machine, although the tests were conducted with a rigid gear of the type shown in the drawings. The American 85 h.p. " Cirrus Hoffman two-seater "Flying Wing," which, with a British " engine, is said to have a speed range of from 30 to 135 m.p.h. An English 85 h.p. "Cirrus" engine is fitted, and drives an airscrew 7ft. in diameter. Positive petrol feed, when the machine is in any position, is ensured by a Ford pump. During tests the landing speed proved to be 28 m.p.h. The landing approach at stall angle is steep, and just prior to the wheels touching the ground the machine goes into a flattened glide. This behaviour is attributed by the designer to the positive rake of the trailing edges and the diverging air flow. With a higher wing loading the characteristic may not be achieved. Vision, it is admitted, is not so good as in con ventional aircraft. The designer visualises, as a future development, a pusher, or twin engined, version, with a three- or four-wheel under carriage. This type, he believes, with a low wing loading, may be the solution to the "Air Flivver" problem. One feels that the view would have to be considerably improved, however, if the machine were eventually to become the " motor car of the air." An Italian Effort As far as is known, the other " flatfish " has npt y;et been built full size, but five different scale models have been tested in the wind tunnels at Rome and Turin. The wind tunnel tests are stated to have given very good results, the drag of the models being low, and the lift maintained up to angles of incidence of about 30 deg. Stability both fore and alt and lateral is reported to have been good, as was also the controllability. The designer of this Italian rhomboidal aeroplane, Piana Canova, has now designed a full-size machine for which the following data have been calculated :— Wing span, 16 ft. 5 in.; length overall, 16 ft. 5 in.; wing area, 141 sq. ft.; tare weight, 352 lb.; disposable load, 308 lb.; loaded weight, 660 lb.; maximum speed, 105-110 m.p.h.; cruising speed, 93 m.p.h.; landing speed, 40 m.p.h.; range, about 650 miles. The engine which it is proposed to fit is the American Aeronca air-cooled flat-twin of 35-40 h.p. "The Flying Plaice" would aptly describe the Italian " all-wing Canova monoplane. On the right, just to show that it takes all sorts to make a world, is a French "no-wing" monoplane, M. Payen's racing single-seater ; equipped with a 400 h.p. engine, it is expected to do great things.
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
