Introduction• An unmanned aerial vehicle, also known as a remotely piloted aircraft (RPA) is an aircraft that is flown by a pilot or a navigator, without a human crew on board the aircraft.• UAV is defined as a powered, aerial vehicle that does not carry a human operator, uses aerodynamic forces to provide vehicle lift, can fly autonomously or be piloted remotely, can be expendable or recoverable, and can carry a lethal or nonlethal payload
ClassificationA. Functional Categories 1. Target and decoy 2. Reconnaissance 3. Combat 4. Cargo & Logistics 5. Research and development 6. Civil and Commercial UAVs
A. In terms of range/altitude1. Handheld 2,000 ft (600 m) altitude, about 2 km range2. Close 5,000 ft (1,500 m) altitude, up to 10 km range3. NATO type 10,000 ft (3,000 m) altitude, up to 50 km range4. Tactical 18,000 ft (5,500 m) altitude, about 160 km range5. MALE (medium altitude, long endurance) up to 30,000 ft (9,000 m) and range over 200 km6. HALE (high altitude, long endurance) over 30,000 ft (9,100 m) and indefinite range7. HYPERSONIC high-speed, supersonic (Mach 1–5) or hypersonic (Mach 5+) 50,000 ft (15,200 m) or suborbital altitude, range over 200 km8. ORBITAL low earth orbit (Mach 25+)9. CIS Lunar Earth-Moon transfer10. CACGS Computer Assisted Carrier Guidance System for UAVs
70K U-2 HAE Global Hawk 60K 50K Heron 2Altitude Predator B 40K 30K Medium 20K Heron 1 Predator A 10K Eagle Eye, Fire scout, Hunter, Pioneer 10 20 30 Tactical Endurance (hours)
Functions1. Remote sensing• UAV remote sensing functions include electromagnetic spectrum sensors, biological sensors, and chemical sensors. A UAVs electromagnetic sensors typically include visual spectrum, IR, or near IR cameras as well as radar systems.• Other electromagnetic wave detectors such as microwave and ultraviolet spectrum sensors may also be used, but are uncommon.• Biological sensors are sensors capable of detecting the airborne presence of various microorganisms and other biological factors.• Chemical sensors use laser spectroscopy to analyze the concentrations of each element in the air.
2. Oil, gas and mineral exploration and production• UAVs can be used to perform geophysical surveys, in particular geomagnetic surveys where the processed measurements of the differential Earths magnetic field strength are used to calculate the nature of the underlying magnetic rock structure.• A knowledge of the underlying rock structure helps trained geophysicists to predict the location of mineral deposits.• The production side of oil and gas exploration and production entails the monitoring of the integrity of oil and gas pipelines and related installations. For above-ground pipelines, this monitoring activity could be performed using digital cameras mounted on one, or more UAVs3. Transport• UAVs can transport goods using various means based on the configuration of the UAV itself. Most payloads are stored in an internal payload bay somewhere in the airframe. With fixed wing UAVs, payloads are often enclosed in aerodynamic pods for transport.
4. Scientific research• Unmanned aircraft are uniquely capable of penetrating areas which may be too dangerous for piloted craft. Aerosonde Pty Ltd. of Victoria (Australia), designs and manufactures the 35-pound system, which can fly into a hurricane and communicate near-real-time data directly to the National Hurricane Center in Florida.• Beyond the standard barometric pressure and temperature data typically culled from manned hurricane hunters, the Aerosonde system provides measurements far closer to the water’s surface than previously captured.• UAVSI (U.K.)also produce a variant of their Vigilant light UAS (20 kg) designed specifically for scientific research in severe climates such as the Antarctic.5. Search & Rescue• UAVs will likely play an increased role in search and rescue. Optical sensor and a synthetic aperture radar can be carried as payload.• The Predators SAR is a sophisticated all-weather sensor capable of providing photographic-like images through clouds, rain or fog, and in daytime or nighttime conditions; all in real-time.
6. Armed attacks• Predators, with high-precision zoom lens cameras, and video cameras with both electric optic and infrared capability that can see at night, can lock on a target for their two Hellfire missiles when they are so far away that the target can neither see them nor hear them.• Sensors bundled in the UAV also calculate wind speed, direction, and other battlefield variables to gather all of this data into a firing solution. This process is known as "painting the target." Once a target is painted, the UAV can unleash its own missiles to destroy the target or send the firing solution to other aircraft or ground forces so they can destroy it.• Predators are 27 feet (8.2 m) long, have a wingspan of 48.7 feet (14.8 m), and are 6.9 feet (2.1 m) high, and can fly at speeds up to 135 mph (217 km/h) and at heights up to 25,000 feet (7,600 m). They can fly 400 nautical miles (740 km) to a target, loiter overhead for 14 hours, and then return to their base.• Reapers have a wingspan of 66 feet (20 m), and are 12.5 feet (3.8 m) high. They can fly at speeds up to 300 mph (480 km/h), and at heights up to 50,000 feet (15,000 m), and can fly for 14–28 hours (14 hours fully loaded.
Predator aviators have described Predator UAV remote pilotpiloting the aircraft as flying an stationairplane while looking through astraw.
Components (USAF Predator)• The Predator UAV is a medium-altitude, long-range aircraft that operates much like any other small plane.• A Rotax 914, four-cylinder, four-stroke, 101-horsepower engine, the same engine type commonly used on snowmobiles, turns the main drive shaft. The drive shaft rotates the Predators two-blade, variable-pitch pusher propeller. The rear- mounted propeller provides both drive and lift. The remote pilot can alter the pitch of the blades to increase or decrease the altitude of the plane and reach speeds of up to 135 mph (120 kts). There is additional lift provided by the aircrafts 48.7-foot (14.8-meter) wingspan, allowing the Predator to reach altitudes of up to 25,000 feet (7,620 meters). The slender fuselage and inverted-V tails help the aircraft with stability, and a single rudder housed beneath the propeller steers the craft.• The fuselage of the Predator is a mixture of carbon and quartz fibers blended in a composite with Kevlar. Underneath the fuselage, the airframe is supported by a Nomex, foam and wood laminate that is pressed together in layers. Between each layer of laminate, a sturdy fabric is sandwiched in to provide insulation to internal components. The rib work of the structure is built from a carbon/glass fiber tape and aluminum. The sensor housing and wheels are also aluminum.
• The edges of the wings are titanium and are dotted with microscopic weeping holes that allow an ethylene glycol solution to seep out of internal reservoirs and breakdown ice that forms on the wings during flight.• The Predator UAV uses run-of-the-mill mechanical systems. A 3- kilowatt starter/alternator supplies the crafts electronics with power; this is supplemented with auxiliary battery power. Forward and aft fuel tanks house rubberized fuel bladders that are easy to fill through gas caps located at the top of the fuselage. An operator starts the engine by attaching the umbilical cord of a Starter/Ground Power Cart to the aircrafts starter-control connector, located in the ground panel on the outside of the plane. An operator stops the engine by hitting a kill switch just behind one of the wings on the side of the plane. For the Engine• The Predators two fuel tanks combined carry up to 600 pounds of 95-octane to 100-octane reciprocating aircraft engine fuel.• The Predator uses 7.6 liters of standard motor oil for lubrication.• In addition to venting, conventional automotive antifreeze is used to cool the engine.• Two 8-pound, 14-amp-hour Ni-Cad battery packs are housed in the fuselage for backup power in case the engine or alternator fails.
1. Synthetic Aperture Radar (SAR) 25. Flight Sensor Unit Antenna 26. Video Encoder2. Inertial Navigation System/GPS 27. De-ice Controller3. Ku-Band Satellite 28. Electro-Optical/Infrared Communications Antenna Sensor/AN/AAS-52(V)14. Video Cassette Recorder Electronics Assembly5. GPS Antennas (Left and Right) 29. Front Bay Payload Tray6. APX-100 Identification Friend 30. Ice Detector or Foe Transponder 31. Synthetic Aperture Radar (SAR)7. Ku-Band Satellite Receiver/Transmitter Communications Sensor 32. Nose Camera Assembly Processor Modem Assembly8. C-Band Upper Omnidirectional Antenna Bracket9. Forward Fuel Cell Assembly10. Aft Fuel Cell Assembly11. Accessory Bay12. Engine Cooling Fan13. Oil Cooler/Radiator14. 914F Engine15. Tail Servo (Left and Right)16. Battery Assembly #217. Power Supply18. Battery Assembly #119. Aft Equipment Bay Tray20. Secondary Control Module21. Synthetic Aperture Radar Processor/AGM-114 Electronics Assembly22. Primary Control Module23. Front Bay Avionics Tray24. ARC-210 Receiver/Transmitter
Future• With the proliferation of remotely-operated and automated combat units, the trend in military technology seems to be moving toward missions carried out by automated warriors, with the flesh-and-blood controllers battling safely from behind computer terminals.• "Nano-drones" are now being developed for targeted killing, that are about 2.5 inches (6.4 cm) long, which like little killer bees will be able to follow their target, even entering a room through an open window.• Aerial refueling tanker drones are also being developed that will allow these drones to refuel, without ever landing.