RADIOWAYS

Evening Post, Volume CXIX, Issue 128, 1 June 1935, Page 21

RADIOWAYS

THEIR AID TO FLYING

DEFEATING THE WEATHER

HAZARDS REDUCED

There has been a great advancement of recent years in the application of radio facilities to aviation, and these undoubtedly have considerably increased the safety element in commercial aircraft services,' says a writer in the "Sydney Morning Herald." Radio is the only means of communication between aeroplanes in flight and the ground organisation, or one with another, following which radio beacons have been developed. With their aid it is possible for a pilot to fly direct to his ultimate objective irrespective of fog, cloud, darkness, side • drift, etc. And radio seems to be destined to become of even greater service to airships than to the ships of the sea today, while possibly some of the illfated aeroplanes forced into the sea would have had their personnel rescued had they been radio equipped. In navigation the all-important question always bothering a pilot is the exact position of his craft at all times. It does not always profit a man to know that he is steering the correct course, when the point of departure is clouded with uncertainty; and there is always the doubt whether the compass is functioning correctly. With sea-going vessels the navigating officer does not solely rely upon his compass and knowledge of drift and leeway, but is continually checking his position by reference to the heavenly bodies. And the radio compass often is used. In the case of an ocean-bound liner, however, the margin of safety is not narrow should it leave its course, and perhaps a week's delay will find it with sufficient fuel and provisions. But it is an entirely different situation with aircraft, because weight is of paramount importance, and extra fuel cannot be carried—perhaps a few hours' delay will spell doom. Oversea, both in Europe and America, radio facilities for aircraft have been extensively exploited, and now it is clearly recognised that commercial aviation could not have progressed so rapidly had it not been for the radio aids that so materially increase the safety factor in flying. - The completed radio network for exclusive use of aircraft in U.S.A. consists of seventy-four radio beacon stations that place practically every city of any size along an airways route; while there are weather forecasts and information always at hand per the medium of the radio. But no one today can doubt the great service that radio can render to flight. As far as Australia is concerned, present indications are that an increase of aircraft services is likely to be much more rapid than the . installation of ground organisations. But before there can be any progress compatible with that overseas there must be far.greater use made of the radio. BRITAIN'S BROAD PLAN. In England the Air Ministry has decided to forestall the large increase in the number and intensity of internal air lines this year by covering the country with a network of "radioways" formed between direction-find-ing wireless stations. With the establishment of a complete system it is hoped to provide any aeroplane operating on any line in the United. Kingdom with wireless direction-find-ing and communicat}onal facilities, and in effect there will be no excuse for the pilot of any machine equipped with radio to report himself lost. The completed scheme that will be available for the assistance of aircraft flying on Continental routes will include seven direction-finders, seven transmitters, and one radio beacon. Of all the new contrivances, how? ever, one of the most promising aids to safety in flying is the radio beacon, for by its use visual bearings are unnecessary with the course always maintained at any altitude and through varying weather conditions. It is not only possible to tell when the aeroplane is drifting, but in what direction—to the right or to the left. In this method, the directional properties of the loop antenna are used by placing two loops at a predetermined angle in respect to each other, connected to a wireless transmitter. By automatic switching arrangements, signals consisting of a dot dash are sent first from one aerial and a dash dot from the other. These signals merge on the true course, and all that is heard is a long dash.- Should dots be heard as well as dashes, the aeroplane is off its course, in which direction is shown by whether the dot is before or after the dash. ENDING MONOTONY. To overcome the monotony of listening to continuous signals, a further system has been developed which makes use of two vibrating reeds on the instrument board. These are encased in a box, and indicate the true course by the reeds vibrating equally. A glance at the device will show whether the direction is being maintained or not with direction of drift being indicated by unequal vibration. Another systeni makes use of a radio guiding channel, that consists of a wireless transmitter at intervals of twenty-five miles or so along the course. Short wave lengths are used, with a vertical antenna which radiates .energy in the form of a beam. The aeroplane on this route is equipped with a simple receiving device that uses the power from the radio channel to light a small indicator lamp on the dash board. The brilliancy of the lamp indicates the course by becoming brighter as it is approached and dimming again should it be passed over. These systems operate irrespective of weather conditions, and commend themselves for many reasons. In the first place, no complicated apparatus is required on the aeroplane with no advanced radio training needed by the pilot, who can use all the facilities after a few minutes' instruction. Weight has been one of the objections to the use of radio with aircraft, but this is overruled by building equipment of suitable dimensions. With fuel carried such an important factor, the system eliminates much waste because side drift is reduced to a minimum and a straight course over a definite route constantly .maintained—much fuel is wasted owing to adverse cross winds, and so on. THE RADIO COMPASS. A recent development for sea navigation is the radio compass, which.as yet has not been adapted for aircraft, although there seems to be no technical or other barrier to prohibit its use, and should be of equivalent benefit to the marine radio compass. Short waves would make possible not only the taking of bearings over enormous distances with a low initial cost, but would permit a great conservation of space aboard the due to the small dimensions of the different compass parts, themselves. The two small loops need not be more than a foot on either side. These are set at an angle of 90deg, so that each makes an angle of 45deg with the line of flight, and so would form the compass proper. The disadvantage of such systems, however, is that they do not show the altitude, although experiments are being conducted that will give by means of radio the actual height that

an aeroplane is flying above ground. This opens up great possibilities. When flying over dangerous country through bad visibility conditions, this would very materially assist the pilot. Professor Gunn, of the Belle View Naval Research laboratories, is said to have one system of radio altitude measurements for aeroplanes in flight. Further improvements are being searched for by the Bureau, of Standards of America, who are working on a system of wireless beams to make safe a blind landing, with radio engineers and aviation experts working together to perfect and adapt apparatus to increase the safety element in flying. WILL DO MORE. Radio already has done a great deal and will do still more, in aiding aircraft navigation, while present developments and what can reasonably be expected of the future have certainly increased the number of mail aeroplanes and commercial services. The hazards of bad atmospheric conditions have been reduced to a minimum, while allowing the services to maintain their schedules because of the greater information available. With a radio altimeter perfected, there will be another valuable wireless aid to navigation; while a system for blind landing is not far from a workable basis. Undoubtedly, the applications of radio facilities will have a considerable influence upon future developments in commercial aviation, and here in Australia, once these services are availed of, commercial flying will go ahead far more rapidly.