POLAR FLYING

Evening Post, Volume CIX, Issue 102, 4 May 1925, Page 7

POLAR FLYING

LAND, WATER, ICE, SNOW

GETTINC4 ABOVE FOG.

Roald Amundsen is now al King's Bay. Spitsbergen, preparing for the 1800 miles flight across the North Pole to Alaska. In the article below one of his associates discusses the conditions of the fiijjlit in the light of previous experience. He points out that the .hydroplanes used had to be ;iblo to take off equally well from laud, water, ice. or snow. . " From our flying experiences in the Spitsbergen, territory during the summer of 1923 it had become quite clear that the aeroplanes to be used for a j Transpokr flight mast be constructed in such a manner that they can land and take off equally well from water, ice, and snow. The possibility of using either. pontoons or skiis as landing gear had been eliminated,-, and we -had arrived at the conclusion that a flying boat with an especially reinforced hull and skii attachment lor ice landings would be the best possible construction. Our attention was drawn to the Dornier type of flying boats as a construction most suitable for our purpose. ! For our postponed 1924 flight- Captain ltoald Amundsen had at first intended to use three or four of the Dornier Delphin type of planes, each with one 185-h.p. B.M.W. motor, but careful calculations showed that the flying radius of these planes would only, under the very best conditions, bo about 700 miles, without refueling, and this was entirely inadequate. We therefore changed over to the much larger type ' Dornier Whale ' flying boat, equipped with two 360-h.p. .Rolls Royce engines. " These engines are not, as in most twin-motored 'planes, placed in the wings, but are placed in tandem between the wings immediately above the hull. This placing of the motors has the great advantage of enabling the aeroplane to continue its flight even i should one of the motors set out. "The radius of the ' Whale ' is about 1300 miles, which is a trifle more than j the distance between the North Pole and Alaska. The entire distance to be flown from Spitzbergen to Alaska is 1800 miles. It will therefore in any case be necessary to first oE all establish a depot somewhere in the unknown territory, where the aeroplanes can stop and replenish their gasolene supply on the final Transpolar dash. I " Whether water or only ice will be found in these latitudes cannot be foretold. If there is only ice, the landings will be somewhat dangerous, as a landing surface may appear quito smooth from above, but nevertheless turn out to.be quite rough upon actual contact, and rough ice is always liable to damage the hull. Experiments are, therefore, now being made with a re- I versible propeller, which if satisfactory will be a valuable asset, as it will enable the 'plane to come to a quick stop after the first contact with the landing surface. " The fog which is quite frequent in the Arctic regions during the summer months will be of no obstacle to the navigation of the 'planes, as we can always ascend above the fog and find the sun, but it will be extremely difficult for the 'planes to find their wayback to the base in foggy weather. The main base must therefore be j equipped with a captive balloon and smoke bombs, which can be sent up above the fog ami guide the pilots back to their landing place. -, . "Apart from the usual aeronautical equipment, very few instruments will be carried along. For the navigation in the Arctic and the determination of a position, only the combination of UlO sun, the sextant, and the chronometer can be relied upon, and nothing else 6hould be used."