DETAIL AND EFFICIENCY

Sun (Auckland), Volume II, Issue 373, 6 June 1928, Page 9

DETAIL AND EFFICIENCY

What a Big Flight Means

SCIENCE WAITS ON NAVIGATOR’S SKILL Exclusive to THE SUN. <B» C. T. P. ULAt, co-pilot to Kinglor# Smith in Southern Cross.) NO. 1. WE left Australia over ten months ago—Why were we so long in deciding to start on the Pacific flight? Why did we not return by steamer? Why were we so confident of success, once we were able to start?

Why do we state so emphatically that ours is a more efficiently organised, equipped and manned flight than others which have failed? These and other questions I am endeavouring to answer briefly in these two articles.

PRIOR to our start on the flight, we would like the Australian and >'ew Zealand public to know details of causes for some ten months’ delay. Also, we feel that if full particulars regarding our organisation and equipment are known and understood by the public, few will feel that -we have anything but success ahead of us. We plan to make a 100 per cent, successful flight—not to start out and be forced to land through lack of fuel, and then (perhaps) stay afloat and be towed to port. The subjects of “blind flying” and ‘heavy load flying” are comparatively Tiew ones. We ourselves were almost 23 ignorant of them as most other Australian airmen until we arrived h»re and studied them. On our arrival here we were (as were those Australians who have criticised us), ignorant of the importance in blind flying of such modern flying instruments as the bank and turn indicator, rate of climb meter, speed and drift meter, etc., and did not then truly appreciate all the difficulties ahead of us. We now know the difficulties and

longest flight from Kauai, in the Hawaiian Islands, to Suva, in the Fiji Islands, is 3,128 miles. The navigation of the craft is, of course, one of the very main essentials in ocean flying, for it would, naturally be quite useless to have the best plane and pilot in the world without someone accurately to navigate them to the desired destination.

Air navigation has its own. peculiar problems as against ordinary nautical navigation, the main one of these being the ’plane’s high rate of drift as compared with the seagoing craft. Ocean currents seldom cause a vessel to drift off its course at more than three or four miles an hour, but with the aircraft the drift can be as high as 60 or 70 m.p.h. VISIBILITY RANGE On the other hand, by virtue of the airplane’s much greater range of visibility the same degree of accurary as required in nautical navigation is not essential in the air. The seaman must be able accurately to navigate his craft within a mile or two of shoals or

the compass errors and for the effect of wind drift. Flying by dead reckoning is contingent on an accurate, reliable compass, and proper drift and ground speed knowledge. On the “Southern Cross” we are carrying four compasses, a master compass and three steering compasses. The master compass is an aperiodic compass with a large bowl, and is mounted on a nonmagnetic tripod in the navigator’s cockpit. For steering we will use the earth inductor compass and two magnetic needle compasses.

Great care will be taken in swinging these compasses before the take-off. Since our plane structure is liable to become magnetised in flight, a pelorous will be mounted, so that checks on the compass can be made in flight from the sun’s azimuth.

The instruments for measuring drift that we are carrying are the Pioneer speed and drift meter, and a pelorus drift indicator, the latter being of very recent design, and not yet in general production. We also carry two kinds of bombs, one giving off smoke for daytime use, the other giving a bright light for night use. These will be dropped from the plane to float on the water, and sights taken after they have been left a couple of miles astern. Without these is it possible, but not so reliable, to utilise the foam flakes of the breaking waves. USING THE SEXTANT Of course, for astronomical navigation the sextant is the crux of the whole situation. If the sextant shot obtained is at all reliable, and an accurate position determined, this is a most valuable means of obtaining drift correction, for it reveals all the errors in the course flown up to the time of taking the sight. When the true horizon can be used, astronomical navigation of aircraft approaches the reliability and accuracy of that of a marine vessel. Unfortunately, too often the sea horizon cannot be used on trans-oceanic flights and an artificial horizon attachment has been designed lor use in aircraft, but on account of its sensitivity it is not as accurate as is desired. A sextant for use on an airplane must be as light as possible and compact. It is often necessary to hold the sextant in the slip stream, and the user must grip it tightly to prevent the instrument being torn from his grasp. The artificial horizon attachment is in the form of a spirit level, and even under favourable conditions the bubble