SLOWER AND FASTER

Taranaki Daily News, 17 August 1935, Page 18 (Supplement)

SLOWER AND FASTER

SHIP AND PLANE PROBLEMS. NEWS FROM WIND TUNNELS. The last word has by no means been said about the shape of the aeroplane, and we shall soon see, slowly moving above our heads, machines with wings of a strange device, says the Children’s Newspaper. In the cave of the winds at the National Physical Laboratory a new kind of biplane has been tested, one that will fly slowly without getting out of control The evolution of such a machine is necessary now that private people fly their own craft and do not wish to acquire wide spaces for alighting. The 1934 report of the laboratory trills us all about As a result of recent experiments it has been found that when the upper wings are tapered and the lower wings tilted up so that their ends reach just behind the narrow tips Of the upper wings a biplane flies wjth safety at an angle greater than the normal stalling point. The aeroplane can fly at an angle of 40 degrees instead of the 20 degrees at which machines now tend to get out of control ’Machines of the new design, therefore, .should become very popular. Design for speed has also been considered at the laboratory, where a new wind tunnel with a wind velocity of 650 miles an hour is used. The flying record is 440 miles, and already the behaviour of miniature wings for aeroplanes at higher speeds has been investigated. So much for the air, but the report is even more interesting when it tells us of the experiments recently made on ships in its great tank. The shipping industry is evidently very alive to its future requirements, for 60 models were tested last year, more than in any previous year.

The models are of wax and are tried out in artificial waves and ciirrrints such as the ship itself will encounter on the high seas. The authorities suggested 54 modifications of the types submitted, all tending to greater speed and safety. Indeed it has been estimated that if only one ship of each type were built, and that ship should sail for 200 days in a life of 20 years, £500,000 would be saved to the industry in coal bills alone. •

Shapes of rudders and propellers as well as the hull have been modified to achieve this result. Scientific measurements of waves in a great storm of the Atlantic show that the distance from crest to errist may extend to 275 feet. For safety apd good navigation in such a/ storm a passenger vessel should, therefore, exceed 700 feet in length, while cargo vessels should exceed 450 feet. But it is not only models of great ships like these that are tested in the tank, for tramps and coastal craft have been tested in order that they may all work as economically as possible in an age when competition is so keen.