New capabilities propel unmanned aircraft systems

By Barry Rosenberg

For a technology that barely existed a decade ago, unmanned aircraft systems have proven to be indispensable in providing intelligence, surveillance and reconnaissance in Iraq and Afghanistan.

The military’s growing reliance on unmanned aerial vehicles was illustrated in April when the Army Unmanned Aircraft Systems Project Office said the service had flown 1 million flight hours. Eighty eight percent of those hours were logged in combat situations in Iraq and Afghanistan, according to the office.

Since the beginning of the war in Afghanistan, unmanned aircraft systems have evolved from platforms that carried little more than a basic video camera or electro-optical/infrared (EO/IR) sensor to ones that are equipped to fire missiles and carry advanced sensors, such as synthetic aperture radar/ground moving target indicator radar. The Army’s latest UAS, the Sky Warrior Extended Range/Multi-Purpose (ER/MP) system, is an example of how far these ISR tools have come in a decade.

“As quantities of these fielded systems increase and as we improve the capabilities of these aircraft, their ability to support the warfighter also increases,” said Col. Gregory Gonzalez, project manager for Army unmanned aircraft systems. “Unmanned aircraft such as the ER/MP [have] fundamentally changed the accuracy and lethality of our soldiers’ weaponry, increased the safety of our soldiers, and even changed the way soldiers see and understand the terrain and situations they face during conflict.”

The growing capabilities of unmanned aircraft can be seen in a sampling of recent developments that are being tested or moved into production from the companies that produce the aircraft and supporting systems for the Army, Air Force, Navy and Marine Corps.

Dismount Detection

For example, General Atomics completed a series of flight tests in May to demonstrate the ability of its Lynx synthetic aperture radar/ground moving target indicator radar to detect people walking or running on the ground. The flight of the Lynx Advanced Multi-Channel Radar on a Predator B marks the first time that radar dismount-detection capability was demonstrated on a Predator-class aircraft, said Linden Blue, president of General Atomics' Reconnaissance Systems Group.

“The ability to detect and track dismounts and slow-moving vehicles over large areas and to cross-cue the onboard video sensor to areas of interest is an emerging military and civilian surveillance requirement,” Blue said, referring to the enhanced capabilities of the aircraft and its EO/IR sensor.

Also in May, General Atomics introduced the Sea Avenger UAS, a carrier-based derivative of its Predator C Avenger, to fulfill the Navy’s need for an unmanned carrier-launched airborne surveillance and strike system. The company formally proposed Sea Avenger to the Naval Air Systems Command through a request for information submitted in April.

And in July, General Atomics began low-rate initial production of its MQ-1C Sky Warrior UAS in support of the Army’s ER/MP UAS program. The Sky Warrior will carry more and larger payloads than the Predator, and it is also planned to be a communications link for communications on the move in the Warfighter Information Network-Tactical program. Through contracts worth almost $400 million, General Atomics will deliver 34 Sky Warrior aircraft, beginning in December 2011, and 16 One System Ground Control Stations manufactured by AAI. The contract also includes delivery of airborne and ground tactical control data link equipment produced by L-3 Communications West, in addition to other items such as automatic landing systems, spares and ground support equipment.

The Sky Warrior program is moving forward as Predator A production is concluding, said Frank Pace, president of General Atomics' Aircraft Systems Group. An earlier version of the Sky Warrior was fielded in 2008 as a quick-reaction program, with the latest version of the ER/MP including four Hellfire missiles and auto-land, takeoff and deicing capabilities.

Unmanned Aerial Refueling

As reliance on unmanned aircraft increases, so does the need to refuel them. Northrop Grumman received a $33 million contract from the Defense Advanced Research Projects Agency in early July to demonstrate aerial refueling of a NASA Global Hawk by a sister ship. The program, designated KQ-X, will demonstrate a number of firsts, including the first aerial refueling of a UAV, first autonomous aerial refueling operation, and first flight of high-altitude long-endurance UAVs in formation.

“Demonstrating the refueling of one UAV by another is a historic milestone,” said Carl Johnson, vice president of advanced concepts at Northrop Grumman Aerospace Systems. “It opens the door to greatly expanded operational utility for UAVs, and, as a side benefit, it promises to increase the safety and reliability of aerial refueling between manned aircraft by reducing pilot workload.”

Through the KQ-X program, Northrop Grumman will retrofit two Global Hawks so that one can pump fuel into the other in flight through a hose-and-drogue refueling system. Major subcontractors on the program include Sargant Fletcher and Sierra Nevada.

Pilots from NASA, the National Oceanic and Atmospheric Administration and Northrop Grumman will fly the Global Hawks from the NASA Dryden Flight Research Center at Edwards Air Force Base, Calif.

Multinational Configuration

Vendors also are redesigning UAS platforms to meet increasing demands to work with allied forces. For example, the Euro Hawk, a derivative of the Global Hawk that Northrop Grumman builds for the U.S. Air Force, made its first flight in June, soaring 32,000 feet over Northrop Grumman’s Palmdale, Calif., manufacturing facility before landing nearly two hours later at Edwards Air Force Base. The company developed Euro Hawk in a partnership with EADS Defence and Security under a 2007 contract from the German Defense Ministry.

“The Euro Hawk marks the first international configuration of the RQ-4 Global Hawk high-altitude, long-endurance UAS and strengthens Northrop Grumman’s first trans-Atlantic cooperation with Germany and EADS Defence and Security,” said Duke Dufresne, sector vice president and general manager of the Strike and Surveillance Systems Division at Northrop Grumman’s Aerospace Systems sector.

Based on the Block 20 Global Hawk, Euro Hawk will carry a new signals intelligence mission system developed by EADS Defence and Security that can detect electronic and communications emitters. EADS also will provide a signals intelligence ground station that receives and analyzes data from Euro Hawk. In addition to the aircraft, Northrop Grumman also will supply a ground station for mission control, launch and recovery.

The German Defense Ministry plans to use the Euro Hawk as a replacement for its aging fleet of manned Breguet Atlantic aircraft, which have been in service since 1972 and are scheduled to be retired in 2010.

In addition to working on the Euro Hawk, Northrop Grumman is developing the X-47B unmanned combat aircraft vehicle for the Navy. The X-47B is designed to autonomously take off and land from the deck of an aircraft carrier. Earlier this year, the Navy and Northrop Grumman tested the integration of existing ship systems aboard USS Abraham Lincoln with the hardware that will be necessary to launch and recover an X-47B.

With a 62-foot wingspan and 38-foot length, the X-47B is about 87 percent the size of F/A-18C aircraft that fly from Navy carriers. The first flight of an X-47B from a carrier is scheduled for 2013.

U.S. and European suppliers aren’t the only companies capitalizing on the revolution in UAS development. One of the pioneers in UAV development, Israel Aerospace Industries, recently reported that Australian, Canadian, French, German and Spanish armed forces in Afghanistan are using UAVs that IAI manufactures.

The Canadian and French air forces have used IAI's Heron UAS, while the Spanish army uses IAI's Searcher III UAS. The German and Australian air forces began to operate the Heron this year. The Heron is a medium-altitude, long-endurance UAS for strategic and tactical missions. With a wingspan of about 54 feet, the Heron UAV can reach an altitude of 30,000 feet and can remain airborne for 50 hours.

Accommodating Heavy Fuel

Another factor in UAS development is the reliance on heavy fuels. One of the primary requirements of Navy and Marine Corps UAS platforms is that air vehicles must burn heavy fuel. Heavy fuel refers to kerosene-based fuel, such as JP5 and JP8 used in diesel or jet aircraft engines. Because ships don’t carry motor gasoline, the Navy has made the development of a heavy-fuel capability for UAVs a high priority to satisfy safety concerns and streamline logistics for remote deployments.

Earlier this year, Boeing’s Insitu subsidiary flight-tested an electronic fuel injection, heavy-fuel engine on its Integrator unmanned aircraft. The Integrator is one of four unmanned systems vying for the Navy and Marine Corps' Small Tactical UAS/Tier II contract, under which the services will phase out the contractor-owned ScanEagle UAV, which Insitu also manufactures. The services will transition to a military-run program of record with a new platform. Other companies in the competition include AAI and its Aerosonde Mk. 4.7, a Raytheon/Swift Engineering team and its Killer Bee, and a General Dynamics/Elbit team with its Storm UAV.

“We have now demonstrated [electronic fuel injection, heavy-fuel] engine performance on both of our Insitu unmanned aircraft, ScanEagle and Integrator,” said Bill Clark, Insitu's vice president of emerging programs. “Heavy fuel with electronic fuel injection provides a 40 percent improvement in mission endurance over the previously demonstrated capability. It represents the next generation of our [heavy-fuel engine] technology, providing a more reliable, safer and easier to operate and maintain engine, and positions us well for our initial deployments later this year.”

According to Insitu, Integrator has demonstrated capabilities such as a communications relay payload, which enables mobile ground units to exchange secure voice and data when line-of-sight obstructions exist, and a Rover 4- and Rover 5-compatible encrypted digital data link, allowing ground forces to securely view real-time data streams on small laptop devices.

Enhanced UAS Capabilities

Another approach to enhancing the flight range of unmanned aircraft is with wing extension kits. AAI, a unit of Textron Systems, recently began delivering extended wing kits for its Shadow tactical UAS.

With the wing kit, the Shadow’s wingspan increases from 14 to 20 feet, which permits a larger fuel cell that increases aircraft endurance from six to nearly nine hours.

“Increasing mission endurance will reduce the number of mission launches and recoveries in a given day, likewise reducing workload for our warfighters in the field,” said Russell Walker, AAI division vice president of tactical unmanned aircraft systems.

The redesigned wing also includes hard points for external stores, which will permit it to carry other payloads beyond EO/IR sensors and full-motion video cameras.

Additional enhancements to the aircraft include wiring harness and software modifications to enable the Shadow to accept a new laser designator payload.

The Army has ordered 100 extended wing kits for distribution to Army and Marine Corps units. The RQ-7B Shadow is the Army’s most widely employed UAS, and Shadow flights accounted for nearly half of all the 1 million UAV flight hours the service has racked up during the last decade.

Another of the Army’s widely used UAVs, the RQ-11 Raven from AeroVironment, is also undergoing an improvement in capabilities. As an Army program of record, the Raven systems will receive digital data links to replace existing, analog systems. The upgrade will let the system transmit additional ISR data in a secure environment.

The Raven is a 4.2-pound, hand-launched sensor platform that provides real-time video imagery during the day or night for over-the-hill and around-the-corner reconnaissance, surveillance and target acquisition. The military services use Raven systems extensively for missions such as base security, route reconnaissance, mission planning and force protection.

Advanced Combat Capabilities

Suppliers also are upgrading the combat capabilities of unmanned aircraft. In mid-July, BAE Systems unveiled a prototype unmanned combat aircraft developed for the U.K. Ministry of Defence. BAE, Rolls Royce, QinetiQ and GE Aviation are developing the concept aircraft, named Taranis, after the Celtic god of thunder.

“Taranis has been three and a half years in the making and is the product of more than a million man-hours,” Nigel Whitehead, group managing director of BAE’s Programs and Support business, said at the event to introduce Taranis. “It represents a significant step forward in this country's fast-jet capability. This technology is key to sustaining a strong industrial base and to maintain the U.K.'s leading position as a center for engineering excellence and innovation.”

About the size of a BAE Hawk Jet, Taranis is jointly funded by the U.K. Ministry of Defense and industry, and is managed by the ministry’s Unmanned Air Systems Project Team at the Defence Equipment and Support organization.

Initial ground-based testing started in 2010, with a first flight expected to take place in 2011.

Micro Manifestations

Meanwhile, smaller, more agile aircraft are reaching new levels of maturity. Known more for its avionics systems and aircraft engines, Honeywell also manufactures the T-Hawk micro air vehicle, which was initially developed for the Army’s Future Combat Systems program and was one of the few FCS elements to survive the program’s cancellation.

In mid-June, Honeywell said the T-Hawk micro air vehicle had recorded its 10,000th flight since its introduction in 2007. That particular flight was part of an explosive ordinance disposal evaluation exercise in Iraq.

The T-Hawk gets its propulsion from a ducted fan, allowing the 14-inch round, 17-pound vehicle to hover and stare with EO/IR payloads for real-time surveillance, without exposing soldiers to enemy fire. The vertical takeoff and landing vehicle can fly as far as 10,000 feet at 46 miles per hour and has an endurance of about 40 minutes.

“Honeywell’s T-Hawk has been used successfully to search for improvised explosive devices, to protect convoys and to hover over an objective area for continuous monitoring in advance of warfighter units,” said Prabha Gopinath, strategic director of the T-Hawk at Honeywell Aerospace.

T-Hawk was introduced and fielded in Iraq in 2007.

From the handheld Raven UAS to the medium-altitude ER/MP UAS, militaries around the world are relying on unmanned systems for their most critical ISR needs. And there’s no going back, most observers say.

“We’ll look back 20-30 years hence and realize we witnessed a revolution in aviation in this switch to unmanned capabilities,” said Chris Ames, director of strategic development at General Atomics. “At the heart of it, we’re delivering persistent situation awareness, which is really the most valued of commodities. That creates a transparent battlefield where you know where the threats are and can counter them.”