KEEPING THE AIRMEN WARM

New Zealand Listener, Volume 2, Issue 36, 1 March 1940, Page 4

KEEPING THE AIRMEN WARM

OW to keep warm is one of ‘the H airman’s great problems, During the winter months, when he is forced to fly at great heights in rarefied air, the intense cold is frequently a greater enemy than bullets, Recent cable messages describing the flights of British and French aviators over the North Sea and Germany have spoken of the intense cold and the danger from ice forming on the machines. Electric Currents Science has now come to the aid of the airman. By an intricate system of electric wiring his body can be kept warm, and special methods have been devised to prevent ice from forming on the machine itself. The. airman’s suit includes electrically heated gloves, boot-soles, jerkin, and sometimes goggles, all designed to operate from a 12-14 volt circuit. A multicore cable with a- five-point plug

and socket leads the current into the suit. A fur-lined jerkin is criss-crossed with fine, insulated wires which thus distribute heat evenly over the airman’s body. Gloves are worn under flying gauntlets and elements lead down over the palms to the finger-tips from a plug in the cuff sockets. In the upper part of the jerkin there is another socket which leads to the goggles and prevents them from misting up on the inside. Similarly there is another lead directing current to the soles of the boots. Protection Against Ice Planes must also be protected against the deadly menace of ice, of which clear ice is the most dangerous, Rime is not so dangerous, and frost is comparatively harmless. The first to suffer from ice are the tips of the ’plane, the propeller and the leading wing edges. If a coat of powdered ice forms on these parts, it swiftly builds up into ~@ thick crust,

giving the machine an extra load, destroying its lifting power and ruining the wing stream-lining. When this happens the propeller may be thrown out of balance and engines may stall through carburettor freezing. Ice also attacks viciously the delicate wires and tubes on which the accuracy of blindflying instruments depend. Important controls working the ailerons and rudder may also get clogged up and frozen. Three methods have been devised to combat the ice menace. Rubber tubing fitted to the leading edges are connected to a motor-driven air pump which cracks off the ice as the tubing expands and shrinks..Another method is to take the exhaust fumes through tubes in the wings, thereby keeping them warm. There are also pastes and liquids which can be smeared over the leading edges, but these are not suitable for thé propeller, which throws them off. Experts now prefer to fit airscrews with slingerrings and spinners which distribute pure alcohol and other anti-ice mixtures over the blades while in flight.