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Part 3 in our UAV series By BOB YOUNG UAVs: While the arrival of the monster UAV Global Hawk in Australia during April may have been big news, there are a host of other smaller UAVs, some with quite remarkable capabilities. Ultimately, they may largely replace piloted aircraft for surveillance and warfare! Weird, Wonderful & even Web-based A fter the record-breaking transPacific flight of Global Hawk to Australia in April, it is safe to say that Unmanned Aerial Vehicles (UAVs) – pilotless, fully autonomous aircraft – have finally come of age. However Global Hawk is not the only advanced UAV plying the skyways; there are a host of others, as we shall see. In fact, it is becoming increasingly difficult to discern the divide between UAVs and normal aircraft that have a fully autonomous capability. Manned aircraft fitted with such items as autopilots, terrain following, inertial navi12  Silicon Chip gation, GPS navigation and auto-land systems are blurring the definition of what comprises an autonomous aircraft. A UAV Ground Control Station (GCS). Here we come smack up against the prime 21st century aviation debate! Is the pilot simply going along to make the passengers feel comfortable or perhaps even to satisfy some primeval need for humans to feel needed? If so, at what point might the pilot be removed? At the end of this trail is the Holy Grail of the UAV dreamer, the UCAV which is the Unmanned Combat Air Vehicle. With the UCAV, all arguments come to an end, at least at a philosophical level, for few would now disagree that sending a pilot into an increasingly lethal hi-tech battle zone is becoming a dubious concept indeed. However, the UCAV is well into the future, awaiting further developments in artificial intelligence (AI) and interference-free command and control (C2) systems. For the moment, such tactics as sending in swarms of drone decoys, simple UAVs, cruise missiles and aircraft fitted with anti-radiation missiles to clear the way for the manned combat aircraft have to suffice. During Desert Storm, for example, in some instances it took up to 32 manned aircraft to clear the way for a single precision ground attack mission. Therefore it is obvious that there are vast cost savings to be made with the UCAV but there are some serious political issues which must be resolved before that. The authorisation of “weapons release”, for some strange reason, is one of them. We already see cruise missiles delivering warheads to remote targets and UAVs fitted with some small weapons, so it is difficult to understand why the UCAV debate should focus so much attention upon weapons release. In the meantime, we are witnessing the movement of unmanned aircraft into an ever-expanding zone of operations while manned aircraft are becoming more autonomous. The question to be resolved is at what point do the two meld into one, if ever? Having said all of that, the May 2001 issue of SILICON CHIP gave a detailed overview of the support systems re- Not all UAVs have to be unmanned! This one, the General Atomics Pelican OPV, can be operated in manned or unmanned mode (hence the cockpit and windows!) quired for Global Hawk. Even a cursory glance, at the command and control systems as well as the data collection and processing hardware, reveals a system of staggering complexity in which the crew have effectively been removed from the aircraft and placed on the ground (out of harm’s way). To move the support equipment around the world requires two Hercules aircraft. Where then is the saving? This is the nub of the manned/ unmanned aircraft debate. But China’s recent downing of the American Orion P3C surveillance plane brings this debate into sharp focus. It also recalls the degrading spectacle of Gary Powers being paraded on the world stage (the U2 pilot shot down over Russia in the 1960s). Clearly, Global Hawk offers a well-defined and clear-cut solution to an age-old problem: a low altitude (as compared to a satellite) surveillance system relatively free of political risk. In the event of a mishap, the remains become just a pile of junk, with little or no emotional baggage for people to become excited about; just another dead robot. It is no accident that Global Hawk is being touted as a replacement for the U2 type of aircraft. General Atomics’ Prowler II, a tactical UAV which can stay aloft for 18 hours, operating at 20,000 feet. It has a 7.31m wing span, 4.24m fuselage and can operate from semi-prepared surfaces. Note the rear-mounted “pusher” motor. June 2001  13 The GA Predator being readied for takeoff. A good idea of the aircraft’s size can be gained by scaling it against the service personnel attending it (the person at the back is standing on stairs!). In the meantime, let’s have a look at a few current developments. driven onto a C-130 Hercules. General Atomics The GA Prowler II is a small (7.31m wingspan), highly capable UAV designed primarily for the US military. It features a single 47kW Rotax 582 engine mounted at the rear of the fuselage in General Atomics Aeronautical Systems are manufacturers of a wide range of high performance UAVs designed primarily for military and research purposes. All are designed to use a common ground station mounted on a small truck and trailer that can be GA–Prowler II Pilot’s-eye view of the controls of a typical UAV – except that the pilot may be thousands of kilometres away from the aircraft and in fact does very little “flying” – that’s all done by computers. This is the General Atomics Ground Control Station, or GCS. 14  Silicon Chip a pusher configuration. This layout is common to all General Atomics UAVs and is dictated primarily by the need for keeping the nose of the aircraft free for sensors. The pusher layout is also responsible for the unusual tailplane and fin arrangements on GA aircraft, to avoid the risk of the prop striking the ground during takeoffs and landings. Prowler’s wingspan is 7.31m and the fuselage length is 4.24m. Maximum takeoff weight is 340kg with 90.6kg of fuel and 45.3kg of payload. Dash speed is 230 knots and endurance is 18 hours. Maximum altitude is 20,000 feet. Sensors include EO/IR (Electro-optical/infrared) and SAR (Synthetic Aperture Radar) systems and the LOS (line of sight) data link range is 200km. It is interesting to note in the Prowler sales brochure the following paragraph under the heading, “Endurance is the key: Long on-station times provide mission flexibility because fewer aircraft are required to do the job. Reducing the number of takeoffs and landings translates to lower loss rates and reduced support personnel requirements...”. This highlights a very important problem in UAV operations. Takeoffs and landings during manned flight represent a major source of potential danger but in unmanned operations they assume a much greater hazard, as the problems of lining up on the runway when the pilot is not in the aircraft are considerable. Traditionally an “inside pilot” is used to control the aircraft in flight and an “outside pilot” is used to handle the takeoffs and landings. The US The Altus is designed specifically for high altitude scientific research and commercial operations. It is used by NASA, the US Dept of Energy and the US Navy. military is fed up to the back teeth with the concept of the outside pilot hence the drive for automatic landing and takeoff systems. According to legend, one Jindivik crew was nicknamed “Snow White and the Seven Dwarfs” because they used to go everywhere (even into the mess) in a single file in order of importance in the flight operation. There was Snow White in the lead, the flight commander, who stayed inside, followed by various other pilots who operated either inside or outside. These included an outside pilot who handled the elevators on the landing and another outside pilot stationed at the end of the runway to handle the rudder and keep the aircraft centred on the runway. As amusing as the story may be, it does indicate the degree of difficulty in operating an aircraft remotely. These days the Americans use a single outside pilot to control the aircraft through a console which looks much like a heavy duty model aircraft transmitter. This is mounted on a stand and connected to the main control van via a long cable. The sight of this fellow standing alongside one end of the runway while a large high-speed aircraft zooms in for a landing raises the hairs on the back of the neck of experienced R/C fliers, let me tell you. One needs very little imagination to see why the General Atomics people state that takeoffs and landings should be kept to a minimum. General Atomics I-GNAT This is a well-proven UAV in service with several military forces and with seven combat deployments under its The new-model GA Predator B majestically soaring up around 65,000 feet – not too far from the edges of space. The most obvious difference between original and new Predators is the dihedral tailplane on the Predator B. It’s also bigger. June 2001  15 I spy with my little eye . . . oh, it’s friendly. A GA “IGNAT” UAV above the USS Tarawa. belt. With its characteristic “upside down” tailplane assembly, it is shown in the opening photo of this feature. Composed mainly of carbon epoxy composites and tested to 6G, the I-Gnat has a wingspan of 12.8m and length of 5.75m. Gross takeoff weight is 703kg and speed is 125 knots. Endurance is more than 40 hours and maximum altitude is 25,000ft. The engine is an 80hp Rotax 912 with the option of a 105hp Rotax 914. GA–Altus Another of the General Atomics family but this time designed specifically for high-altitude scientific research and commercial operations. Currently it is used by NASA, the US Dept of Energy and the US Navy. Altus is quite a large (16.76m wingspan, 6.71m length) and very capable UAV. Available with a variety of engine options it is capable of operating up to 65,000ft. Takeoff weight is 974kg with a payload capacity of 148.5kg. a figure of 25 hours against the 40-hour endurance of the RQ-1 Predator with its lower airspeed of 118 knots. Payload is quoted as 295.5kg and ceiling as 45,000ft. Sensors carried include a SAR with 4-inch resolution, ESM and radio relay and an improved optical package that can view personnel at ranges of up to 50 nautical miles. All of the modern UAVs can carry sensor packages of outstanding resolution and performance and it is the improvement in the entire array of airborne electronic systems that has contributed so much to the success of the modern UAV. Altair The latest and one of the largest of the Aeronautical Systems UAVs, the Altair is designed with the scientific and commercial communities in mind. Capable of carrying a 400kg payload to 40,000ft and beyond and staying aloft for 32 hours at a stretch, the Altair is a very capable UAV indeed. Wingspan is 19.5m in the standard configuration, with an extended wing of 25.6m available as an option. Length is 11m and gross takeoff weight is 3182kg. Maximum cruising speed is 151 knots. The engine is a 700hp TPE331-10 turboprop. The fault-tolerant avionics include ATC (Air Traffic Control) voice relay, Mode 3C transponder, NASA FTS, INS (Inertial Navigation System) and GPS (Global Positioning System). The data links use C-band for line of sight and Ku-SATCOM for over-the-horizon. Navigation may be remotely piloted or fully autonomous. All of these aircraft represent a major leap forward in UAV technology over the past few years and while not in the same class as the Global Hawk, they are quite potent performers in their own right. Northrop Fire Scout A conventional helicopter of some size, the Northrop Grumman Fire Scout is designed primarily for shipboard operations where launch and recovery present serious problems, especially in rough seas. Fitted with an auto take-off and landing system, the Fire Scout can operate from any aviation-capable warship and from unprepared landing zones. Length is 6.97m, rotor diameter 8.38m, height 2.87m and gross weight is 1157kg. Maximum speed is 125 GA–Predator B This is is the big brother of the RQ-1 Predator and features a 19.5m wingspan against the 14.62m span of the original Predator. The B version is also fitted with an Allied Signal 331-10 gas turbine engine. Predator B has a gross takeoff weight of 2730kg and a speed of 210 knots. Endurance has suffered somewhat in the quest for speed, with 16  Silicon Chip Northrop Grumman’s “Fire Scout”, designed primarily for fully automated takeoff and landings aboard ships. Launch and recovery of conventional (manned) helicopters often present serious problems, especially in rough seas. hour-glass, it is essentially a helicopter with twin, contra-rotating rotors located at the waist of the hour-glass shaped fuselage, body shell or whatever you may like to call it. This vehicle is so strange-looking that it steps outside of the boundaries of normal aviation terminology. Manufactured by Bombardier Aerospace in Canada, the Guardian is integrated into the UCARS automatic landing system and thus provides a VTOL system capable of fully automatic take-off and recovery. A unique feature is the landing grid that locks the vehicle onto the deck when touchdown is made, thereby eliminating any bounce due to rough seas. The system can also operate from rough, uncleared terrain using the same grid. Rotor diameter is 4m and gross take-off weight is 350kg. Speed is a maximum of 85 knots and endurance is 6.25 hours. Range is 100-200km, depending upon the payload carried and the time on station. Height is 1.84m and fuel capacity is 180 litres total, carried in two tanks. Bombardier Aeropsace’s CL-237 Guardian UAV. It has contra-rotating blades and is designed for perch-and-stare operation from ships and other limited-space locations. It’s also suitable for rough terrain work. knots; service ceiling is 6100m with an endurance of greater than 6 hours. The usual combat radius is 200km with a 4-hour loiter at the target. CL-327 Guardian Here we have the one of the strangest of all UAVs. It is designed to overcome the problems associated with shipboard operation, where recovery in rough seas on restricted deck space presents almost insurmountable problems. Looking for all the world like a flying Wanna fly a UAV? Hook into www.observatine.net and you may get the chance to do just that! The man in the fashion-statement-blue outfit is none other than our own Bob Young. Yes, he does exist! Web-controlled UAV The above UAVs are all very useful for the professional soldier and professional scientist but what can UAVs offer to the average Joe or Jill? How about being able to log onto the net and take control of your own personal UAV for an hour or so? Then steer your UAV around Uluru or the Daintree, soaking up the sights in the It might look like a model helicopter to you but it’s another web-based UAV complete with video camera (in green). June 2001  17 Observatine’s web-based UAV which you will be able to fly from the comfort of your own PC. It’s something like Flight Simulator without the simulation – it’s real! comfort and safety of your own lounge room, with adequate stocks of tinnies and chips to hand. Sound a bit far fetched? Not if Zina Kaye of Observatine, an innovative Sydney based company has her way. To join the Observatine team, log on to www.observatine.net and be prepared for a new experience. The web will never be the same again. Observatine is a pod and boom pusher aircraft of 3-metre wing span 18  Silicon Chip and 2.6m length. Fitted with a Zenoah 74cc horizontal twin engine, autopilot, GPS nav, data uplink/down link and most important of all, a video link, here is a tiny package that packs a mighty punch. Weighing in at 25kg gross takeoff weight, Observatine carries a 7kg avionics payload. This aircraft is a flying machine that gives a viewer the experience and control of flying, while having a bird’s eye view of the land. Since Observatine is managed by a web-server configuration, web-based viewers may be pilots and viewers. This project was realised initially in Australia and relies on ongoing support from programmers in The Netherlands, Germany, the UK and Poland. To sum up Observatine, here are a few words from Zina Kaye, “Flight, in the context of entertainment, refers to the desire for movement, speed and travel. Games, such as Microsoft Flight simulator, offer the user an interface that employs metaphors of control, but that can only follow the action. Observatine wishes the user to be carried away by offering the viewer the chance to pilot a real flying object. Observatine is a model aeroplane with on-board system that gives a viewer on a web-site the control of the aircraft and a bird’s eye view of the land. The aeroplane is situated and certified in Sydney but it is intended that the choice of radio frequencies will permit it to be flown also in Europe & USA”. So there you have it, a UAV for couch potatoes. One can only imagine how some people may wish to employ it. SC We live in exciting times.