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This is part of a larger article, on A History of UAV's.

After some fumbling, the US military now seems to be acquiring an effective fleet of battlefield UAVs. The US military is entering a new era in which UAVs will be critical to SIGINT payloads, or ECM systems should be in widespread use following 2010, with the UAVs controlled and relaying data back over high-bandwidth data links in real time, linked to ground, air, sea, and space platforms. The trend had been emerging before the American war in Afghanistan in 2001:2002, but was greatly accelerated by the use of UAVs in that conflict. This chapter describes contemporary American tactical UAV systems.

US ARMY RQ-7A SHADOW 200 / SHADOW 600

• After the collapse of the Outrider effort, the US Army went through a fourth attempt to procure a battlefield UAV. AAI followed up their Pioneer UAV with the similar but refined Shadow 200 UAV, and in late 1999, the Army selected the Shadow 200 to fill the tactical UAV requirement. The Army requirement specified a UAV that used a gasoline engine, could carry an electro-optic / infrared imaging sensor turret, and had a minimum range of 50 kilometers (31 miles) with four hour endurance on station. The Shadow 200 offers at least twice that range.

The Shadow 200 looks something like a Pioneer, but has a sharper nose, a ring around the pusher prop, and an inverted-vee tail, supported at the ends by twin booms. The UAV is powered by a 28.5 kW (38 hp) rotary engine. The Army requirement dictated that it be able to land in a soccer field.

  AAI RQ-7 SHADOW 200:
  _____________________   _________________   _______________________
  spec                    metric              english
  _____________________   _________________   _______________________

  wingspan                3.89 m              12 ft 9 in
  length                  3.41 m              11 ft 2 in
  payload                 27.2 kg             60 lb
  launch weight           149 kg              328 lb
  maximum speed           225 km/h            140 mph/123 knots
  service ceiling         4,575 m             15,000 ft
  endurance               > 5 h

  launch scheme           RATO booster or runway takeoff.
  recovery scheme         Net or runway landing with hook.
  payload                 Day / night imager or other payload.
  guidance system         Programmable with radio control backup.
  _____________________   _________________   _______________________

The Army ordered a total of 44 Shadow 200 systems. The service felt that since the Shadow 200 was basically a proven system, there wouldn't be any hangups in evaluation, but the Army's "jinx" proved hard to break, with the evaluation suffering from crashes and accidents. The problems were resolved, and the Shadow 200 went into LRIP in 2002.

• Each Shadow 200 system includes three UAVs, two ground stations, and support vehicles for equipment and personnel. The Army is now working to expand Shadow 200 capabilities. A SIGINT payload is in development, and is scheduled for service in 2008. It will swap out with the EO turret. The Army has also considered arming the Shadow 200 with light munitions.

In a particularly interesting application, the (AMC) in Huntsville, Alabama, has developed a supply canister, named "Quick-MEDS (Medical Emergency Delivery System)", that can be carried in pairs by a Shadow 200 and parachuted to front-line troops with medical supplies or other emergency gear.

Quick-MEDS is an interested idea and worth looking at in detail. It looks like a little fat aerial bomb. It has a loaded weight of 9 kilograms (20 pounds), 75% of that being payload; dimensions of 81 by 20 centimeters (32 by 8); and four "lattice fins" on the tail. These are shaped like paddles, with the flat side facing the airstream, and contain a lattice of airfoils to provide the maximum flight surface in the smallest form factor. The idea was developed by the Russians and is licensed under Russian patents. Quick-MEDS has a crushable nose full of plastic foam and a parachute in the tail.

Quick-MEDS could also be deployed by any helicopter or light aircraft. It has been designed to be scalable to 90 kilograms (200 pounds) and a -guided version is being designed, for deliveries to troops in close contact with an enemy.

• It is unclear if the Shadow 200 saw service in the Afghanistan campaign of 2001:2002, but it did fly operational missions during the US intervention in Iraq in 2003 and the subsequent occupation of that country. The operating conditions in Iraq proved hard on the UAVs, with heat and sand leading to engine failures, leading to a high-priority effort to find fixes with changes in system technology and operating procedures. Despite the difficulties, the RQ-7A Shadow 200 was enthusiastically received by field commanders, and regarded as an important asset in helping fight Iraqi insurgents fighting US occupation forces.

The Army has been seeking additional funding to buy more Shadow 200s. Production shifted to a generally improved "RQ-7B" variant in the summer of 2004. The RQ-7B features new wings increased in span by 91.4 centimeters (36 inches); the new wings are not only more aerodynamically efficient, they are "wet" to increase fuel storage for greater range and endurance. Endurance has been increased to 6 hours, and payload capability has been increased to 45 kilograms (100 pounds). Avionics systems have been generally improved, and the new wing is designed to accommodate a Tactical Common Data Link (TCDL) when that system becomes available.

Romania has purchased a number of Shadow 200s. These Romanian machines have been used in support of Polish troops serving in Iraq.

• AAI has also built a scaled-up Pioneer derivative known as the "Shadow 600". It also resembles a Pioneer, except that the outer panels of the wings are distinctively swept back. A number of Shadow 600s are in service in several nations, including Romania.

  AAI SHADOW 600:
  _____________________   _________________   _______________________
  spec                    metric              english
  _____________________   _________________   _______________________

  wingspan                6.83 meters         22 feet 5 inches
  length                  4.70 meters         15 feet 5 inches
  height                  1.22 meters         4 feet
  empty weight            163 kilograms       360 pounds
  max loaded weight       272 kilograms       600 pounds

  maximum speed           210 km/h             132 mph / 115 knots
  service ceiling         5,180 meters        17,000 feet
  endurance               14 hours

  launch scheme           RATO booster, catapult, or runway takeoff.
  recovery scheme         Parachute, net, or runway landing.
  payload                 Day / night imager or other payload.
  guidance system         Programmable with radio control backup.
  _____________________   _________________   _______________________

RQ-8A / RQ-8B FIRE SCOUT

• While the Army was working on Outrider, the Navy was moving on to its second generation UAV, as old Pioneers were being withdrawn from service. The Navy requirement specified a vertical takeoff & landing (VTOL) aircraft, with a payload capacity of 90 kilograms (200 pounds), a range of 200 kilometers (125 miles), an endurance on station of three hours at an altitude of 6 kilometers (20,000 feet), and the ability land on a ship in a 46 km/h (29 mph) breeze. The UAV was to fly 190 hours between maintenance.

There were three finalists in the competition, which was designated "VTOL-UAV" or "VTUAV". Bell, Sikorsky, and a collaboration of Ryan and Schweizer Helicopters submitted designs. The Ryan-Schweizer UAV was selected as the winner in the spring of 2000. The "RQ-8A Fire Scout", as it was named, was a derivative of the Schweizer three-passenger, turbine powered 330SP helicopter, itself a derivative of the Hughes 300 series helicopters, with a new fuselage, new fuel system, and UAV electronics and sensors.

The initial prototype of the Fire Scout was piloted in initial tests, flying autonomously for the first time in January 2000. The Rolls-Royce Allison 250 turbine engine ran on JP-5 and JP-8 jet fuel, which is nonvolatile and safe for shipboard storage.

The Fire Scout was to be fitted with a sensor ball turret that carries electro-optic and infrared cameras, and a laser range finder. It was to be controlled over a data link derived from the Northrop Grumman Global Hawk UAV, operating over a line of sight to a distance of 280 kilometers (172 miles). The control system was to be fitted onto a ship, or could be carried on a Hummer light vehicle for US Marine service.

• The Fire Scout program suffered a setback in November 2000, when the initial prototype crashed and was destroyed, leading to a schedule slip. Despite the accident, the Navy was expected to move quickly to begin production and introduction of the type, but then in late 2001 the program went into a holding pattern that made outside observers dizzy.

Although progress on the project had been regarded as satisfactory, the Navy decided the Fire Scout didn't meet their needs after all, and cut funding for production in December 2001. However, the development program continued, and Northrop Grumman pitched a range of improved configurations to anyone who was interested. As it turned out, the US Army was very interested, awarding a contract for seven improved "RQ-8B" evaluation machines in late 2003.

The RQ-8B will feature four-blade main and tail rotors, in contrast to the larger-diameter three-blade rotors of the RQ-8A, to reduce noise and improve lift capacity and performance. The four-blade rotors had already been evaluated on Fire Scout prototypes. They will boost gross takeoff weight by 225 kilograms (500 pounds) to 1,428 kilograms (3,150), with payloads of up to 317 kilograms (700 pounds) for short-range missions.

The RQ-8B will be fitted with stub wings as well. The wings will serve an aerodynamic purpose, but it appears they will be used for carrying armament as well, such as Hellfire missiles; Viper laser-guided glide weapons; and in particular pods carrying the "Advanced Precision Kill Weapon (APKW)", a laser-guided 70 millimeter (2.75 inch) folding-fin rocket, which the Army sees as ideal for the dirty little wars of the current day. The Army is also interested in using the Fire Scout to carry up to 90 kilograms (200 pounds) of emergency supplies to troops in the field.

The RQ-8B is being modified to permit rapid swapout of payload configurations. The current sensor configuration of a day/night turret with a laser target designator will of course remain an option. Alternate sensor payloads in consideration include a SAR with Moving Target Indicator (MTI) capability; a multispectral sensor; and a SIGINT module. The Army wants the Fire Scout to operate as an element of an integrated ground sensor network as well.

Other features under consideration for the production RQ-8A include an uprated engine, a new exhaust system to reduce infrared signature, retractable landing gear, and a satellite communications link. The Army may buy up to 180 production Fire Scouts though 2010.

Ironically, the Army interest revived Navy interest in the program, with the Navy ordering eight "Sea Scout" RQ-8B derivatives for evaluation. This seems particularly surprising, given the dismal past history of joint US Army / US Navy UAV efforts. However, Navy officials also have been making noises about adopting the Bell Eagle Eye tiltorotor UAV, discussed later, as a follow on, suggesting that the Sea Scout is regarded simply as an interim solution. Northrop Grumman sees possible sales of up to 73 RQ-8Bs to the Navy & Marine Corps, and sees more possible sales to the US Coast Guard, for US homeland defense, and to Britain.

BAI AEROSYSTEMS BQM-147 DRAGON DRONE

• The BAI Aerosystems (BAIA) Dragon Drone, which as mentioned earlier served in the Gulf War as the "Exdrone", is the product of over a decade of refinement and is now in widespread service.

The Dragon began life in 1986, when the US Marines Corps contracted with the Applied Physics Laboratory (APL), an offshoot of Johns Hopkins University in Baltimore, Maryland, that works on government technology development contracts, to build a small piston-powered UAV as an "expendable jammer" for battlefield electronics warfare. The program was logically named "ExJam". BAI Aerosystems was a subcontractor to APL and provided airframe parts.

A little "creeping featurism" infected the program as the Marines considered more applications for the little drone, and in 1987 the program was given the new name of "Expendable Drone" or "Exdrone". However, APL wasn't able to meet the schedule requested by the Marines for fielding the Exdrone, and so the program was passed on to BAI Aerosystems, with the Navy assisting by developing a video imaging system for tactical reconnaissance.

The NASA Langley Flight Research Center also assisted in the development effort, performing wind-tunnel tests and making recommendations for aerodynamic improvements, and after these changes the BQM-147A Exdrone went into service with the Marines in time to help them chase the Iraqis out of Kuwait City. A few years later, the UAV-JPO also bought several hundred Exdrones for demonstrations and training to help get tactical officers in tune with battlefield UAV capabilities.

The current "Dragon Drone" is an improved version of the Exdrone, obtained through a 1996 contract with the Marines. BAI renamed the UAV since the Exdrone wasn't really all that expendable, given that it carried a reasonably sophisticated sensor system and flight avionics. The Dragon Drone is a flying wing with a single tailfin that is symmetrically designed to allow it to fly with either side up.

The Dragon Drone is powered by a small piston engine. It can carry one of three different plug-in turrets, featuring daylight color TV with a laser rangefinder, daylight color TV, or infrared imager. It can also be fitted with an auxiliary fuel tank for increased range.

  BAIA DRAGON DRONE:
  _____________________   _________________   _______________________
  spec                    metric              english
  _____________________   _________________   _______________________

  wingspan                2.44 meters         8 feet
  length                  1.52 meters         5 feet
  empty weight            25 kilograms        55 pounds
  max loaded weight       43 kilograms        95 pounds

  cruise speed            130 km/h             80 mph / 70 knots
  service ceiling         3,000 meters        10,000 feet
  endurance               3 hours

  launch scheme           Pneumatic catapult.
  recovery scheme         Net capture or skid landing.
  payload                 Day / night imager or other payload.
  guidance system         Programmable with GPS & radio control backup.
  _____________________   _________________   _______________________

• The US Coast Guard is now procuring a "navalized" version of the Dragon Drone under the name "Condor", and intends to use it with Coast Guard cutters and similar small ocean-patrol vessels. The Condor will be useful for missions such as search and rescue or hunting drug trafficers.

Launching and recovering a UAV off such small vessels is troublesome. Naval UAVs have traditionally been launched with a catapult or RATO boosters, and recovered using a net. Not only is this approach unsuited to smaller vessels, it is also not particularly reliable even on large vessels, with catapult launches causing drone damage, catapult failures leading to loss of the drone, and recoveries similarly leading to damage through collisions and unintended ditching.

A Saint Louis, Missouri, company named Advanced Aerospace Technologies Incorporated (AATI) has come up with an alternative scheme for launching and recovering a Dragon Drone or other small UAV from small vessels. The scheme involves the use of a parasail and is referred to the "runway in the sky (RITS)". In AATI demonstrations, a Dragon Drone is attached to a piggyback frame that harnesses the drone to the parasail. The parasail is reeled out into the wind until it reaches an altitude of about 250 meters (800 feet). The drone is then released, diving until it builds up enough speed for the operator to pull it out of the dive and sent it on its mission.

In recovery, the parasail is used to lift a tow line into the sky, with the tow line trailing a series of recovery lines hanging between the parasail and the ship. The drone is flown into the recovery lines, and a snaplock mechanism on the drone's wing grabs onto a line. The drone is then reeled back down to the ship. The tow line has more "give" to it than a recovery net, reducing the likelihood of damage.

The current RITS scheme can handle UAVs weighing up to 180 kilograms (400 pounds), but AATI thinks it can be scaled up to handle larger aircraft. AATI claims the system is inexpensive and easy to use. They also point out that the parasail could also be used to loft an antenna to allow over-the-horizon communications with a UAV. Whether the Coast Guard intends to use this scheme or not is uncertain, but it certainly is an interesting concept.

BELL EAGLE EYE

• The Bell Eagle Eye tiltrotor, another one of the competitors in the Navy VT-UAV competition, performed its initial flight in 1993. The Eagle Eye is powered by a single Allison 250-C20 turboshaft engine mounted in the center fuselage, with a transmission system driving a tilting rotor at the end of each wing.

  BELL EAGLE EYE:
  _____________________   _________________   _______________________
  spec                    metric              english
  _____________________   _________________   _______________________

  wingspan                4.63 meters         15 feet 2 inches
  length                  5.46 meters         17 feet 11 inches
  rotor diameter          2.9 meters          9 feet 6 inches
  max loaded weight       910 kilograms       2,000 pounds

  maximum speed           322 km/h             200 mph / 174 knots
  service ceiling         6,100 meters        20,000 feet
  endurance               8 hours
  _____________________   _________________   _______________________

Bell promoted the Eagle Eye for a decade without finding a buyer, but in the summer of 2002, the US Coast Guard ordered the UAV as part of the service's broad "DeepWater" re-equipment effort. It must have been a great relief to company officials. The Coast Guard machine will be slightly scaled up from the company demonstrator, and will have a maximum speed of 370 km/h (230 mph / 200 knots) and an endurance of 5.5 hours with a 90 kilogram (200 pound) payload. The company hopes to have the first scaled up USCG Eagle Eye available by November 2004, with initial deliveries in 2006.

After a long period of frustration, the Eagle Eye is finally beginning to attract attention. The US Marines plan to buy eight Eagle Eyes in the Coast Guard configuration for evaluation, though a production buy would of course be optimized to Marine specifications, with a laser target designator, as well as better performance and survivability.

The US Navy has also expressed some interest and there have been inquiries from various foreign governments. In the summer of 2004 Bell established a relationship with Sagem in France and Rheinmetall Defense Electronics in Germany to sell variants of the Eagle Eye to European governments. Bell will provide raw airframes, the European partners will provide payloads and other gear as specified by customers, and Bell will then perform system integration.