Radio Broadcast (May 1928-Apr 1929)

What RADIO Has Done for AVIATION %N ENGLISH RADIO ENGI An English answer to the charges made by "Anonymous" in the November number of this magazine, that aviation has not made the proper use of radio, points out the fact that in the "air-minded" countries of the Old World radio is playing its part in the safety of air navigation. The implication is that as America develops its commercial air lines to the point at which they are now developed in Europe, radio will be recognised as an essential part of airplane equipment. — The Editor M 'UCH has been said in the past about the failure of aviation to make the proper use of radio, particularly on such hazardous ventures as transoceanic flights. An unusually stimulating article on this subject by "Anonymous," entitled "What's the Trouble with Aircraft Radio?" appeared in the November, 1927, number of Radio Broadcast. As its title suggests, "Anonymous" is looking rather for what radio has not done for aircraft than what it has done. We may fairly claim that the latter is even more strik / ing than the former. No radio engineer who has had experience in aircraft radio would attempt to minimize the difficulties to be encountered in adapting radio to aircraft use, but that these difficulties are not insuperable has been proved time and time again since the institution in England, by the Marconi Company, of what I believe were the earliest experiments in this direction at that famous nursery of European aviation, the Hendon Airdrome near London. Incidentally, these "laboratories" were in the Graham White sheds at Hendon, so it cannot be said that the radio engineers were out of touch with the flying men. To-day the Marconi Company is working in close collaboration with the Air Ministry and aircraft operating and constructing companies, and has recently completed the construction of an entirely new installation at the London Air Port at Croydon, with four transmitters working on different wavelengths, which is claimed to be the most up to-date airdrome radio installation in the world. During the war the evolution of the radio telephone set for airplanes was pushed forward, and in the summer of 191 5 the first spoken message from an airplane to the ground, in England, was obtained by Major Prince in collaboration with Captain H. J. Round — then members of the experimental section of the Royal Flying Corps at the Brooklands Wireless School — by means of a continuous wave tube transmitter. Continuous inter-machine working was not an accomplished fact until 19 17, but it was used for formation control in the latter stages of the war. In the last few years the development of radio for fighting planes has proceeded to a stage far in advance of that reached by November, 19 18, with the result that the wonderful squadron "air drill" that may be seen in the world's leading air forces has become a practicable and safe proposition instead of — as it would be without radio — a hazardous adventure. For purposes of IN THE CROYDON RADIO CONTROL TOWER The four transmitters at Mitcham, 45 miles from the Croydon Air Port, are controlled from this room. At the left is the direction finding unit; next to it is the g-tube multiwave receiver amplifier. Transmission takes place on telephony and telegraphy. 288 this "air drill" in close formation the Marconi Company has now developed a small, light set using an aerial system attached to the wings. It is, however, to the enormous possibilities oP civil aviation that the world is turning its eyes to-day; and no thoughtful person will quarrel with "Anonymous" when he says: "Before passengers are permitted to risk their lives, regulations regarding suitable radio equipment and personnel to operate it should be laid down." This state of affairs has already been reached in all the principal countries in Europe. But, before we examine more closely the working of this commercial aviation policy in Europe, let us look at some of the more spectacular achievements of radio — because "Anonymous" has selected some spectacular non-achievements. WHERE RADIO HELTED THE FLYER \ A /HEN the British Airship R34 flew across v " the Atlantic in July, 1919, radio was used in a very practical manner by its navigators for direction finding and position finding. In addition the airship was in touch with the Air Ministry in London practically throughout its voyage, and during the whole time that it was over the Atlantic was never out of touch with land on one side or the other. Just what this would mean to a commercial air line of the future need not be emphasized. And there is another achievement in connection with radio on airships of which the radio engineer can justly be proud. In a heavy gale in April, 1925, the British miJitary airship R33 broke away from its mooring mast at Pulham and floated off over the North Sea, driven by a furious wind. Thanks to the work of its radio operator, however, the airship was able to keep in touch with its base throughout the time of its involuntary flight. Officials there and at the Air Ministry knew all the time exactly what the position of the airship was and how it was faring. The information that they were able to give to Flight Lieutenant Booth, who was the chief officer in the airship at the time of the breakaway, as to his position and the extent of his drift