The courier-index., 1918-08-02
PLIERS HAVE NO
 HEIGHT SENSATION
AFTER ONE GETS UP A WAY THE GROUND LOOKS ALL THE SAME, SAYS R. B, THICKER IN NEW YORK WORLD.

Ask any airman what 1t feels like up at 10000 or 10000 feet for that matter. His reply will invariably be the same, Sensation of height? There isn't any" writes Lieut., K. B. F7ricker in the New York World.
 The average individual who has not experienced flight is sure he would be giddy. faint or sea sick He judges by his feeling when look ing down over the edge of cliff, the Eiffel Tower or some such structure. If the airman could view his height by looking down a trail ing rope or a sheer wall stretching from his machine to the ground 1t might be the same for him. From 20 900 feet the ground looks much the same as from 5000 or 4,000. Minus a height indicator an mex perienced airman could not judge his height within 50 per cent
 Air sickness among pilots occurs very rarely. It is sometimes brought
 
 the machine in ''bumpy' weather, when the air is full of pockets Then the airman who is bilious or other wise out of trim may experience air sickness, which is much the same as sea sickness.
 Different, altogether, however, are the effects of the reduced air pres sure at extreme attitudes. A British aeronaut, Glaisher, of the Greenwich Observatory, bailooning as long ago as 1862. stated that at 29,000 feet he lost the use of his arms and legs, later the muscles of his back and neck, and the power of speech and vision. Finally he became uncon- seious until the balloon descended to lower attitudes. No airplane as yet has reached the height attained on this balloon trip Special oxygen ap- paratus would be necessary for great attitudes to bring the supply to the airman's lungs up to the normal.
 When contact patroIling' over the trenches, or low flying strafing ground targets, the sense of speed IS present; but at normal heights (nor- nal for the airman means about 5000 meet) the relative speed of the machine over the ground is small. The earth seems to crawl away be- hind
 Airmen who are learning to fly do not realize the advantage of height. The messengers seat is usually not fitted with height indicator. The first question put to the instructor after a flight is 'How high did we goe" And the answer is probably the first rough guess that comes into the pilots head. He very likely | never looked at the aneroid during the flight until he was heading into the wind for the last bit of straight glide down to the aerodrome, To the pupil the thought of climbing | higher than before seems to carry a sense of greater danger.
 No one but the experienced airman realizes the full truth of the maxim safety in height and nothing but "conking" engines will bring home this truth. The honling instinct comes out directly the engine is at fault. The pilot immediately looks around and tries to make for his aerodrome. Woe betide the pilot who turns wind down near the ground in an effort to get back without sufficient height in which to head into the wind again. The hom' ing instinct is a very natural one Everything else is strange ground Although it all looks flat from above, the airman knows how extremely varied it can be. This is where the seapIane pilot has an advantage the sea will never be so deceptive as the sides of the hills or be hedg' ed in with fields or dotted with hous' es and trees.