Evening Republican, Volume 21, Number 296, Rensselaer, Jasper County, 19 December 1918 — A PERFECT WIRELESS TELEPHONE IS AMERICA’S GREATEST WAR SECRET [ARTICLE]

A PERFECT WIRELESS TELEPHONE IS AMERICA’S GREATEST WAR SECRET

> For Months American Airplanes Here and in Europe Have Been Equipped With Apparatus by Which Their Movements Were K Directed by Voice Comma Tests Fail to Impair Its Complete Efficiency.

WILLIAM A. WILLIS In the New York Herald. Amwrim’s biggest war secret the development and perfection of the wireless telephone, is no longer a secret. Eight years of work by wizards of science in the United States army, aided by civilian workers In radio problems, rame to successful consummation last February. Since that time American airplanes here and in Europe have been equipped with apparatus which has made vocal communication between them while flying, as well as communication with the earth, a simple matter. The secret has been well kept for many months. Outside of members of the air service few have known iL Those few have maintained absolute silence. The war department has regarded the solution of the problem of what now- is called “voice command flying” as one of the greatest and most important achievements of the age. Its value in war was so tremendous that extraordinary precautions were taken to prevent the slightest inkling of the development reached from leaking out. Germans Had Only a HinL German aviators knew that the American flying men had some advanced method of communication but did not know exactly what it was. The French and British flying forces have dabbled with the wireless telephone In coiinection with airplanes for some time; the British meeting with some success. It remained, however, for men of the American air service to perfect the radiophone. This they have done. The writer is the first civilian outside of Newton D. Baker, secretary of war; Mr. John D. Ryan, director of aircraft production, and one. or two other highly placed government officials to observe this latest of great American inventions tried out. It was on receipt of word from Mineola that the hardest tests the new Wireless telephone had ever been put to had failed to impair its complete efficiency that Mr. Ryan in Washington made public the first news ever given out the new discovery. These tests were made at Hazelhurst and Roosevelt fields, near Mineola, under the personal direction of Maj. Gen. William L. Kenly, chief of the division of military aeronautics, who came over from Washington for the specific purpose of finding out if there was any feat in aviation that could break down the "voice com. mand” system of communication. When he quit after an afternoon of hair-raising stunts with every kind of aircraft from the slow training planes to those swift eagles of the air the De Havllands, he expressed himself as completely satisfied that the wireless telephone as part of airplane equipment has come to'stay and is in shape to meet almost any situation short of an actual smashup. No Need for Further Secrecy. The ending of the war has made further secrecy in connection with this amazing invention unnecessary, in the opinion of Mr. Ryan and General Kenly, there are certain secrets Jn connection with the apparatus used that naturally will not be revealed. But the principles Involved were made clear without reserve by Col. Clarence " C. Culver of the aviation corps, the man who has led the work of perfecting the wireless telephone and who is credited by scientists with the major part of the credit for its success. Those who have seen airplanes in battle formation many thousands of feet In the air have perhaps wondered how at a given moment they have all turned or looped or dived as one machine, maintaining the precision almost of West Point cadets on dress parade. The answer is that each man - has a telephone receiver fastened in his helmet through which he has re* eeived the order of the squadron commander as clearly and audibly as if he was an Infantryman on the ground being addressed by his company cap-

tain. The roar of the motor and the whir of the propellers have no effect whatever on his power of clear transmission or on the ability of his men to receive his words. The tremendous value of the invention which Colonel Culver and those associated with him have brought to perfection, is not easily understandable by civilians. But through its operations it is now possible to send students into the air alone and direct their dally drill from the ground, thus eliminating the necessity of endangering experienced pilots, who, as instructors, have hitherto been obliged to go up in the air with their pupils. It also is now possible to train aviators in advanced flying, the instructor on the ground being able to see the work of his student and instantly correct his faults. In training and directing pilot gunners and bombing pilots the wireless telephone also is of inestimable value. The tests of the new invention were conducted in the presence of General Kenly, Colonel Culver, Col. Millar'd F. Harmon, Jr., commander of the first provisional wing; Maj. Ralph Cousins, commander of Roosevelt field; George C. Norton, a lawyer, and the writer. Lieut. Hudson R. Seerlng took the air in a De Haviland at Hazelhurst field, at an order from General Kenly. Looks Like Ordinary Transmitter. Colonel Culver took what looked to be an ordinary telephone transmitter in his hand. This transmitter was connected by a wire wifii a small wireless plant built on the field. Lieutenant Seerlng had a receiver in his helmet but no transmitter, so he had been instructed to indicate “yes.” by a slight forward tip of his machine; and “no” by waving his plane frofn side to side, much the same as a boat rocking in the water. When Seering was 2,500 feet in the air and perhaps half a mile from where the party was standing Colonel Culver, speaking into the transmitter In a tone only slightly above normal, said “Can you hear me, Seering?” Instantly the machine took a forward dip. “Do you hear me clearly?” asked Colonel Culver. The machine took another forward dip. “Are you cold?” was the next question. The machine instantly began rocking from side to aide. “Well, climb a bit higher,” ordered Colonel Culver. Without a second of delay Lieutenant Seerlng started up. “That’s high enough,” said Colonel Culver. V The machine flattened, outi Then followed a bewildering series of “stunts," each in response to a vocal order from the ground, the flyer doing nothing on his own initiative. During Lieutenant Seering’s flight, he ranged from 2,500 feet to 3,500 feet altitude. At no time was he more than three miles from where General Kenly and Colonel Culver stood. Neither his altitude nor his distance from the transmitter, however, affected his ability to hear whatever was said to him. From Hazlehurst field General Kenly took his party to Roosevelt field, where the performance given was so remarkable that it threw into the shade the test made with Lieutenant Seering, astonishing as that seemed at the time. Nineteen battle planes, the swiftest of the De Havilands, equipped with Liberty motors, took the air at once. They were commanded by Maj. Joseph E. Rossell, acting as squadron commander. Eighteen of the pilots were equipped with receiving apparatus. Major Rossell alone had a transmitter equipment. This air fleet shot off into the south at a speed of 130 miles an hour, but soon returned in a V formation. Major Rossell flying higher and well behind his squadron. Passing over Roosevelt

field the squadron went through several maneuvers, forming right lines and left lines, breaking off in differ-* ent directions and swinging back into line again. Everything was done with perfect precision. . Colonel Culver explained that Major Rossell was giving every order by word of month and that every man in the fleet was 'getting orders at 'he exact instant “Now if you want to you can stand here on the ground and hear Major Rossell give these orders, and you can at the same time that you bear them see them carried out,” said Colonel Culver. - . He led us to a small shack from the roof of which dwarf aerials projected, put receivers over o,ir ears, and a moment-later I heard a strong vole* lay: * " . J “By the right flank.” Then there was a second of hesitation, followed by a stentorian, long drifwn-out “Gq,” and away off in the eastern heavens I saw the long line of small dots swing off to the right, and for thu moment, opt of sight. And those worfis came from Major Rossell, spokgn in an ordinary tone, 6,000 feet in the air and fuliy five miles from where 1 was standing. And I was informed that it would have’been xjust the same if he had been further away. However, the range of the new wireless telephone is one of the secrets that the division of military aeronautics is not revealing just now. For more than an hour I heard Major Gossell put his squadron through a drill and at the same time that I heard his orders I saw them executed. These things took place while these 19 airplanes were rushing along at more than a hundred miles an hour at an altitude ranging from 4,000 to 6,000 feet, And with the man giving the order fully two miles from the nearest of his men. The apparatus used • for wireless telephoning is so simple and so com. pact that one would never notice either the transmitting or receiving devices on an airplane unless his ah tention was 'called to it. d With the consent of General Kenly, Colonel Culver gave me a great deal of information about these devices and the following facts are the first published about' what perhaps is the greatest invention of the war. Description of Device. The transmitting set consists of a power plant, a set box, a transmitter or microphone and an antenna system. The power plant consists of a generator driven on the windmill principle by the passage of the airplane through the air. It is placed somewhere In the open, usually on the running gear or on one of the wings, and its tiny propeller blade whirls vigorously. as the airplane travels along. The so-called set .box receives the power from the generator, converts it and places it on the aerials In the form of sustained or undamped waves. The voice entering the transmitter varies the electric current on the wires, which are connected as in ths ordinary telephone. In the set box the variations received from the transmitter, are converted and act to effect a modulation of the continuous or undamped waves already referred to. The antenna system consists of an aerial of one or two trailing wires of approximately 150 feet in length, strung out from the wing tips. This is counterpoised by the wires and other metallic parts of the airplanes all bonded together. These two elements of the antenna system are analogous to large overhead wires and to the “ground” of a land wireless station. The receiving set consists of a receiving set box, a head receiver, a source of power and an antenna system. The latter is the same as the antenna system In the transmitting bet. The source of power is a small Storage battery. The head receiver is into the aviator’s helmet in such a manner as to exclude sounds from the motor reaching the pilot’s ear and Interfering with his hearing. The set box proper contains apparatus quite similar to the receiving apparatus of a first-class wireless station. However, it possesses a number of refinements over these which Increase the audibility of Incoming signals, withstand vibration and minimize weight.