AIR NAVIGATION

Hauraki Plains Gazette, Volume XXXVI, Issue 4834, 25 May 1925, Page 1

AIR NAVIGATION

HOW A PILOT FINDS HIS WAY. EXPLAINED BY A. J. COBHAM. I uni constantly asked by my friends and all folk I meet (raid Aia.i J. Cobham, rhe pilot who took Si> Sefton Bracker from London to Burma and back, “How do you find your way in the air ?’’ There is no mystery about it; with a little practice you can find your way far more easily in the air than on the ground, for the simple reason that owing to the altitude you have a better view and the whole countryside is laid out before you like a map, the miniature scale- of which you carry in your hand in the aeroplane. There arc many methods dr finding your way in the air. ranging from simple map reading, in which a pilot may follow a road or railway, knowling that it leads to his destination, to the most up-to-date methods of scientific nevigation, in which the latest types of compasses and drift sight iudicatcrs and navigating Instruments arc. used more or less in the same style as on board ship. In such cases a navigator is carried on board wno works out his bearings and corrections and plots his course .at a little desk in the cockpit and tells tne pilot what bearing ,to take. When a beginner goes up for the first time he is invriaably lost the moment he leaves the aerodrome, and it is not until the instructor points out some landmark that he can find out where he is.

On my flight to Rangoon and back 1 naturally had to be my own navigator, and I carried maps ;or the entire journey of the country that mighr. be covered on our survey. The scale of my- maps was about 16 inches to one mile, and I carried in all nearly fifty sheets.

Every night I prepared the maps required for the next day’s flight, and made a little study of the best route to be taken. Then in most cases I would draw straight lines over die different courses that T oroposed to take, and measured with a protractor their coinpass bearing and jolted them down alongside. On the following day the maps <cquried would all be in consecutive order and specially folded for the portion in use, and thetse would slip into a yack in the cockpit. On tn start of the flight I would fly on my first compass course and look out for each little landmark, such as a village, a hili, a river, or railway, that crossed or came on my pencilled line on my map. If these landmarks were not beneath me, but a few miles way to the right or left, then I knew tha; owing to the wind I was drifting off my direct course, and so to allow for this I would steer two or three points to 'the right or left so that my compass course after about the flnst 20 miles with its little corrections would bring me over every landmark on my pencilled line on the map. Of course at times I had to follow the contours of the map, which I would occasionally ’check with -<nv compass, or in other cases follow my way through a mountain gorge or just hang-on'to a track-over the desert, and ar times we went over' scores of miles on a compass hearing without recognising anything on the way until we came out bn some definite feature that I would have to k cate.