FLYING IN WINTER

Poverty Bay Herald, Volume LXIII, Issue 18992, 17 April 1936, Page 3

FLYING IN WINTER

ICE FORMATION PREVENTION APPARATUS (From a Special Correspondent) LONDON. March 10. The first British airliner to be fitted with apparatus to prevent ice formation oil the wings, and tail control surfaces is n De Havilland D.H.B6a four-engmed biplane, named Dryad, which is ready for delivery to Imperial Airways. It wdl he put into service on the company's European routes, living over regions that have known serious dislocation of ailservices during the winter months because of the presence from time to time of conditions of humidity and low temperatures iin which ice may form with terrifying rapidity on the lift and control surfaces of aircraft. Ice formation, which occurs to' the "reatest extent at the leading edges of wings and control unite.- destroys the safety of an. aircraft by adding to the weight, that it must carry and a much more important factor—by distorting the, shape of the wings and thereby depriving them of the greater part of their "lift."

The device fitted in the Dryad deposits small quantities of a liquid mixture of ethylene glveol and ethyl alcohol on the leading edges. This mixture lowers the freezing, point of water and melts any layer of ice in immediate contact with (he surface, thus eliminating adhesion or the ice to the surface and enabling the 'powerful wind forces always acting on the structure of an aircraft in flight to blow the rest of the ice away. The mixture is led to the leading edges through piping and a, rubber lube punctured at short intervals along its length. Liquid forced through this lube moistens a porous leather covering stretched along the leading edge: as long as this covering—which conforms, exactly to the shape of the wing or- other surface and, therefore, does not affect aerodynamical efficiency—renmin's moist, ice cannot form in iYii'v ipiantitv. The device is under the control of the pilot, who can turn on the liquid at will. Including three gallons of the mixture, which is enoiu>li for five hours' flyinrr, the whole outfit in the Dryad weighs onlv 651 b. Tl is simple in design, installation and maintenance.