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REMOTE CONTROL BY BOB YOUNG Unmanned aircraft - the ultimate in remote control During the 1991 Gulf War, the usefulness of unmanned aircraft passed almost unnoticed. What did not pass unnoticed was the suffering of the pilots captured after being shot down over Iraq. However, if unmanned aircraft were used to their full capability, there would be very little risk of pilot casualties. · In the Vietnam War, America lost more than 2500 manned aircraft and about 5000 of her.airmen were killed. Nearly 90% of all US servicemen taken prisoner were pilots and crewmen. Interestingly enough, the Vietnam War saw the birth of a successful remotely piloted vehicle (RPV) in the form of the Ryan 147 series. This jet RPV is now out of production but lives on in the form of the Chinese CHANG HONG 1, a reverse engineered AQM-34N which was shot down over China around 1970. It was unofficially reported that up to 20 MIG fighters made between 30 to 50 passes at this little drone before they shot it down. The story is always the same in regard to the survivability of these tough little aircraft. They are very hard to shoot down. Consider the following quotes: (1). "This ... target was ... flown against the concentrated gunfire of the (British) Home Fleet during an exercise in the Mediterranean. For two hours, every gun in the fleet tried in vain to destroy this lone, slow and fragile target, but it was recovered safely". (2) . "Thousands of rounds ofradardirected fire from a sophisticated air defence gun, as well as hundreds of rounds of fifty calibre, were expended on an unmanned vehicle flying well within range. The unmanned vehicle flew on without a scratch". There is little room for doubt about the survivability ofRPVs but the truly noteworthy feature of these quotes is that they were issued at an interval of 47 years. The first quote, which comes from Richard A. Botzum's "30 Years of Target Drone Aircraft", was discussing a flight made by a Fairy Queen biplane in 1933. The second was quoted during a US Gorernment hearing in 1980. The Vietnam experience If more proof is needed of the survivability ofUMAs (unmanned aircraft), then consider the following statistics. In the same war that saw 5000 US airmen killed in the skies over Vietnam, drones flew a total of 3435 operational sorties in the years between 1964 and 1975. Of these, the recovery rate in the early days, was approximately 84 % . In the latter years, as more sophisticated models were introduced, the recovery rate climbed to well over 90%. After Vietnam, the proponents of UMAs were confident that RPVs had proved their case and were set to become a major new "force multiplier" in military thinking. Instead, the expected upturn in fortunes failed to materialise and five years after Vietnam, the USA did not have one single operational RPV in its inventory. It was left to Israel to prove the point on the value ofRPVs and to take the case to its logical conclusion. Israel first recognised the value ofRPVs during the Yorn Kippur war of 1973, when it was able to reduce its manned aircraft losses by using inexpensive Chukar decoys to deceive and saturate Egyptian SAM batteries along the Suez Canal. Shortly after that war, the Israeli government charged the IAI and Tadiran companies with developing small, versatile, low-signature RPVs, able to send back real-time intelligence via a direct video link, and capable of being operated in the field by ordinary soldiers after only 3-6 months training. The Scout and Mastiff mini-RPVs came into their own in June 1982 when Israel launched it's "Peace for Galilee" offensive against Syrian forces in Lebanon. Some of the drones, equipped with radar reflectors to simulate full size aircraft, acted as decoys to draw the fire of Syrian gun and missile batteries in the Beka Valley. Whilst this deception was in progress, other RPV s carrying explosive charges remained undetected by Syrian radars, enabling them to home in on the radars' emissions and destroy them on impact. The air defence batteries, thus blinded were totally vulnerable to atMAY 1993 53 tack by manned strike aircraft, which wiped them out completely. In this object lesson in the combined use of manned and unmanned aircraft, not one single Israeli pilot was lost and Syria quickly paid Israel the compliment of acquiring Russian drone systems for its own forces. How it all began How did all of this automated mayhem begin? Interestingly enough, as with most things electrical, with none other than Nikola Tesla. He had begun active work on building remotely controlled devices in 1893, although capable of a multitude of operations, but the consummation of my labours was delayed until 1897 ... When first shown in the beginning of 1898, it created a sensation such as no other invention of mine has ever produced."' "His basic patent was obtained in November, only after the examiner in chief had come to New York and witnessed the performance of his vessel, for he claimed it was unbelievable." "These first robots, he wrote in 1919, he had originally considered crude steps in the evolution of the art of Teleautomatics. As he had con- "The famous woman pilot Hanna Riech then undertook to fly the monster and identified the problem as a Gyro toppling under launch "G" forces. The rest is history." the concept had occurred to him earlier. During the next two or three years, he had built several mechanisms that could be actuated from a distance and showed them to laboratory visitors, but the destruction of his laboratory by fire interrupted these activities. The following quotes are from the book, "Tesla, Man Out Of Time" by Margaret Cheney: "In 1896 he wrote ' ... I designed a complete machine ceived it: 'The next logical improvement was its application to automatic mechanisms beyond the limit of vision and at a great distance from the centre of control, and I have ever since advocated their employment as instruments of warfare in preference to guns ... In an imperfect manner it is practicable, with the existing wireless plants, to launch an aeroplane, have it follow a certain approximate course, and perform some operation at a distance of many hundreds of miles"'. The above passages refer to Tesla's radio controlled boat and submarine models which were demonstrated publicly in the late 1890s. They featured two separate RF channels which were used in an AND gate configuration. The basic patents used in these very early models played havoc with some heavyweight inventors and the courts were kept busy for many years. Marconi was affected as we will see, and the computer industry was subsequently denied patents on AND gate devices. Tesla filed his basic radio transmission patents on September 2nd, 1897 and they were granted as Patent Nos. 645,576 and 649,621 on March Zoth, 1900. Later they would be contested in long litigation by Marconi but first Tesla would sue the Italian Government for infringement. Marconi used Tesla's basic patent 645,576 to develop the equipment he used on December Zoth, 1901 to transmit the letter "S" across the Atlantic from Cornwall to Newfoundland. H. Otis Pond was walking with Tesla that day and commented to Tesla that it looked as though Marconi had got the jump on him, to which Tesla replied: "Marconi is a good fellow, let him continue. He is using 1 7 ofmy patents". On June 21st, 1943, the US Supreme court reversed an initial finding in Marconi's favour to rule that Tesla AF For many years you have probably looked at satellite TV systems and thought "one day". 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I Name: _ _ _ _ _ _ _ _ _ _ _ __ I Address: _ _ _ _ _ _ _ _ _ _ _ __ 1 1 - - - -- - - - P'code: _ _ _ _ _ 1 Phone: _ _ _ _ _ _ _ _ _ _ _ __ I ACN 002 174 478 10/92 Taken in August 1977, this photograph shows three versions of Australia's very successful pilotless target aircraft, the Jindivik. In the foreground is one of only two manned versions, while in the background is the first pilotless version. The current version of the Jindivik is just in front of the hangar. had anticipated all other contenders with his fundamental radio patents. The next step in the development of the RPV occurred in 1913 when Lawrence Sperry first tested his gyro stabiliser - the world's first automatic pilot - in a Curtiss biplane. A mere four years later, an improved version became the heart of Sperry's "aerial torpedo ", which made several successful flights for the US Navy from Sperry's Long Island airfield. British experiments In 1917, the British War Office, concerned with the heavy losses of British aircraft to the "Fokker scourge" across the Channel and the effects of the Zeppelin bombing raids over England, looked into the possibility of developing pilotless, remotely controlled aircraft for interception and ground attack missions . A young Army officer, Second Lieutenant A. M. Low, was placed in charged of the newly-formed RFC Experimental Works and given the task of applying his expertise in radio technology to the problem. Under the cover name of AT (Aerial Targets), a series of small aircraft, some designed by such pioneers as H. P. Folland and Thomas Sopwith, were produced for trials. During Law's first public demonstration at Upavon in March 1917, the AT misbehaved so badly as to provoke Major Gordon Bell, one of the War Office observers, into the now classic remark that he "could throw my bloody umbrella farther than that". Subsequent efforts were scarcely more successful and thus no ATs became operational. The main problems lay in the launch techniques and aircraft stability and in fairness to Low it must be pointed out that when the launch was successful, the radio techniques he developed could exercise long range control from a "mother" aircraft. The Nazis had exactly the same problem with the Vl (Doodle-Bug) in WWII and after many failures of the unmanned version, a manned version was built. This fix was to no avail and there followed several fatalities. The famous woman pilot Hanna Riech then undertook to fly the monster and identified the problem as a Gyro toppling under launch "G" forces. The rest is history. The concept of manned prototypes of the earlier UMAs was quite common and there was even an early manned version of Australia's very successful UMA, the Jindivik. These days, obsolete manned fighter aircraft are routinely converted to drones at the end of their safe service life. Next month we will continue this discussion of remotely piloted vehicles of which there are several dozen different types in service with defence forces ar~mnd the world. References. (1). Air International, February 1992, Unmanned Aircraft directory. (2). Jane's Battlefield Surveillance Systems 1992-93. (3). Tesla, Man Out Of Time, by Margaret Chaney. Prentice-Hall, Inc. Englewood Cliffs, N.J. 07632 1981. MAY 1993 55