Unmanned Systems North America 2010
At the Association for Unmanned Vehicle Systems International’s (AUVSI) Unmanned Systems North America 2010 show, held Aug. 24-27 in Denver, Colo., there was abundant evidence that composites will continue their conspicuous role in unmanned vehicle (UV) development. The HPC staff was on hand for the event as more than 5,000 UV professionals searched the aisles at the Colorado Convention Center for the latest in applicable technologies.
The big question HPC had for show exhibitors was, What effect will ongoing and potential military drawdowns in Iraq and Afghanistan have on the UV market? Without exception, those who benefited from the large military buildups that powered much of the unmanned aerial vehicle (UAV) development in the past eight years told HPC they have few worries about the future. Many governments in the Middle East are writing orders for UAVs as they prepare to shoulder security chores that the presence of large U.S. forces will no longer mitigate. At least in the short term, there also will be a need to replenish the Pentagon’s spent unmanned equipment. More importantly, a vastly expanding civilian and law-enforcement market for aerial, seaworthy and ground-based UVs are expected to push continued growth in the unmanned market for the foreseeable future, especially if and when Federal Aviation Admin. (FAA) flight rules can be modified to permit wide civilian use of unmanned aerial systems. On the show’s first day, Derrick Maple, senior unmanned systems analyst at HIS Janes (Bracknell, Berkshire, U.K.), produced data to back up the positive anecdotal testimony. He foresees demand for nearly 50,000 units from now until 2019, 75 percent of which will be small UAVs weighing less than 66 lb/30 kg. The annual growth of the (currently) $105 billion (USD) unmanned aerial system (UAS) industry will be between 5 and 10 percent per annum, with double-digit growth between 2020 and 2030. Maple commented that although the lack of flight rules for the national airspace will continue to constrain commercial and civil UAS applications for a time, the airspace should open up by 2020, paving the way for greater growth.
A key show buzzword was autonomous — referring to the ability of pilotless craft (air, sea or land) to operate not only without a pilot in the cockpit, but also without a pilot remotely stationed on the ground. Few exhibitors of unmanned systems neglected to mention their autonomous options, and sprinkled among the splashier vehicle exhibits were dozens of booths staffed by marketers of the software and control hardware and sensing technologies designed to make unmanned operations free of the need for human intervention.
Among the more than 400 exhibitors were many who use composites to make UVs and those who supply the composite materials they use.
In the air
Composites continue to be the materials of choice for UAV airframes. QinetiQ (London, U.K. and McLean, Va.), for example, touted the recent record-breaking flight of its Zephyr solar-powered UAS. The aircraft, weighing a mere 112 lb/51 kg, has a 73-ft/22.5m wingspan and is designed to hold station in the stratosphere for weeks or even months. Company spokesmen told HPC that the all-carbon fiber UAS is nearly ready for production, and it will be manufactured at QinetiQ North America’s Huntsville, Ala., facility. At the other end of the size and capabilities scale, Cornerstone Research Group Inc. (CRG, Dayton, Ohio) was one of several purveyors of ducted-fan-powered micro-aerial vehicles. CRG’s aptly named HALO, a vertical takeoff and landing (VTOL) airborne sensing system, was on display in two sizes. The robust, round, all-carbon composite structure almost 2-ft/0.61m in diameter with a centrally mounted, rechargeable-battery-powered coaxial, counter-rotating ducted fan, was paired with its similar but smaller predecessor (see “Learn More,” p. XX). Targeted to law enforcement and fire/rescue first responders, the remotely piloted surveillance craft are designed to negotiate labyrinthine urban environments under circumstances that are dangerous to human agents.
Insitu (Bingen, Wash.) was recently awarded the Small Tactical Unmanned Air System (STUAS)/Tier II contract by the U.S. Naval Air Systems Command (NAVAIR) for its Integrator UAS, and the company held a press conference to describe the aircraft’s capabilities. U.S. Navy Admiral William Shannon, Insitu’s primary contract customer, described the aircraft as a “truck” with open architecture, that is, a very flexible composite platform that can accommodate multiple sensors and instruments for many roles, especially as miniaturization evolves — as sensors get smaller, they can be carried on smaller tactical vehicles. Shannon confirmed that the Navy is committed to buying large numbers of Integrator craft and reiterated that its predecessor, Insitu’s ScanEagle, has proven itself for years on board Navy ships at sea.
Aurora Flight Sciences (Manassas, Va.) emphasized its GoldenEye 80 VTOL UAS, originally developed under a Defense Advanced Research Projects Agency (DARPA) program. The heavy-fuel powered vehicle can be transported and lifted with a two-man crew, is capable of speeds from hover to 80 kts/92 mph with a payload of 25 lb/11.3 kg and meets military noise requirements. The company also supports a wide array of composite projects for customers, including the Global Hawk’s airframe components.
Mansik Johng, A160 advanced design manager at Boeing Defense, Space & Security (St. Louis, Mo.), provided an update on testing of its composites-intensive A160T Hummingbird unmanned rotorcraft at the AUVSI 2010 show (Aug. 24 to 27 in Denver, Colo.). The A160T features rotors and aerostructures constructed of carbon fiber composites. It has 5,500 to 6,500 lb (2,495 to 2,948 kg) gross weight, 2,500 lb/1,134 kg payload capacity, a 20,000 ft/6,096m ceiling. The Hummingbird measures 35 ft/10.7m nose to tail and features four rotors that have a diameter of 36 ft/11m. In 300 hours of testing to date, the A160T has achieved 18.7 hours of endurance with a 3,000 lb/1,361 kg payload, which Boeing claims is a world record for a UAV. A160T production began in March this year. Johng revealed that carbon fiber composites on the craft are currently hand layed, but noted that automated systems are under evaluation. Boeing has committed to manufacture 21 aircraft, despite the crash of an A160T during testing earlier this year that is still under investigation.
Brock Technologies Inc. (Vail, Ariz.) was on hand to highlight its UAS concepts, including the Spear and Havoc unmanned crafts made with composites. The Spear has an affordable platform that can be configured in various ways — the entire wing can be shifted forward or backward along a longitudinal spine to balance payloads — for specific intelligence, surveillance and reconnaissance (ISR) missions. Havoc is a long-endurance craft with a modular design that features multiple launch options, with or without landing gear, for varying missions and multiple payloads.
Northrop Grumman Corp. (El Segundo, Calif.) had on static display its new Fire-X medium-mange vertical unmanned aerial system (VUAS), a full-scale helicopter based on a Bell 407 airframe. The Fire-X, which can be flown manned or unmanned, is in competition with Boeing’s Hummingbird and Kaman Aerospace’s K-Max unmanned helicopters for military resupply operations. Expanding on the company’s Fire Scout small VUAS for surveillance and ISR, Fire-X can conduct ship-based and land-based missions and carry a 3,000 lb/1,364 kg payload. Also on display was the company’s awe-inducing Global Hawk and X-47B UAS, along with information about the Bat UAS, a small, catapult-launched blended-wing aircraft (see “Learn More”) originally developed by Swift Engineering Inc. (San Clemente, Calif.).
Exemplifying the decidedly entrepreneurial bent to the UAV market, former U.S. Air Force munitions expert Chris Miser (CLMax Engineering, Fort Walton, Fla.) showcased his inexpensive UAV option, the Ox. Miser helped test a series of expensive weaponized UAVs while in uniform but thought he could do it better. Now out of uniform and in business for himself, he claims he can make a practical airframe for $20,000 to $30,000 — about half the going rate for “low-end” UAVs of the same size and capabilities. Easily assembled and disassembled by one person without tools in less than 15 minutes, the Ox can be transported in two cases and a wing/boom tube container and, in this form, could be checked as luggage on a commercial airliner. With a 15 ft/4.5m wingspan and empty weight of only 70 lb/32 kg, it reportedly can carry a useful load (payload plus fuel) of up to 40 lb/18.1 kg in payload bays with a useful internal volume of more than 50 L (1.7 ft³). Two underwing “hard points” are each capable of supporting 15 lb/6.8 kg. Depending on the payload-to-fuel ratio, Miser’s aircraft can stay aloft from 1 to 12 hours of autonomous or radio-controlled flight. CLMax has placed six UAVs with Miser’s former employer and expects that low-priced, workhorse UAVs will bring unmanned technology to a much wider range of potential clients.
Several exhibitors showcased target drones, one of the earliest commercial uses of UAVs. Prominent among them was Composite Engineering Inc. (CEI, Sacramento, Calif.), with a display of three miniatures of its full-size (10 ft/3m long, 6.5 ft/2m wingspan), trailer-catapult-launched, jet-powered drones. Lightweight yet tough, CEI’s “top end” composite-airframed drones fly at up to 400 nautical mph during gunnery/antiaircraft missile tests, yet surprisingly it can be shot down, repaired and then reused, surviving to fly an average of eight missions. Nearby, the focus was on affordability at the Griffon Aerospace (Madison, Ala.) exhibit. The company makes target drones for U.S. Army weapons training and evaluation, and it produces the Outlaw and Broadsword unmanned systems for surveillance, with varied payload configurations. Both systems have tough, rugged and cost-effective composite airframes for harsh environments and are capable of both launcher- or runway-based operations.
Under the sea
A fast-growing UV segment is systems for surface and submerged operations at sea. Hydroid Inc. (Pocasset, Mass.) displayed its Remus line of small autonomous deepwater craft and a family of larger HUGIN deepwater autonomous unmanned vessels (AUVs) built by its parent company, Kongsberg Gruppen (Kongsberg, Norway). A 3m/10-ft long composite AUV was recently used to scout the ocean floor in preparation for oil giant BP’s offshore drilling of the relief well that was used to plug the ruptured well in the Gulf of Mexico, which resulted in the world’s largest oil spill.
Meanwhile, Harbor Wing Technologies (Seattle, Wash. and Pearl Harbor, Hawaii) explained the composites technology behind its unique autonomous unmanned surface vessel (AUSV). Designed for surveillance, reconnaissance or environmental monitoring, the wind-powered, tri-hull design eschews a conventional sail in favor of what the company calls a “hard wing” airfoil, or WingSail. The HWRT X-1 subscale prototype, funded in part by the U.S. Navy, performed well in recent tests near Hawaii. Production of the first full-size AUSV is underway.
Although its booth presentation was dominated by publicity efforts for its Zephyr success, QinetiQ’s display also showcased its strengths in development and manufacture of unmanned sea and ground vehicles.
The event demonstrated that the unmanned vehicle market has been a huge boon to composite propeller manufacturers, who otherwise might have been devastated during the general aviation downturn prompted by the recent recession. Wichita, Kan.-based McCauley Propeller Systems mounted a massive exhibit, offering composite props for systems ranging from full-size pilotless aircraft to ducted-fan craft and microdrones. According to company sources at the show, McCauley plans to offer a composite propeller for certified general aviation aircraft in the near future; FAA testing is currently underway. The new propeller will reportedly weigh significantly less than existing certified composite propellers.
Similarly, Sensenich Propeller Co. (Plant City, Fla.), a competitor in the FAA’s manned Experimental aircraft category, told HPC that it is pursuing an FAA-certified prop. It also is searching for UAV applications for its light composite prop blades produced via a combination of resin transfer molding and inflatable mandrels. Long-time marine-prop specialist Piranha Propellers (San Luis Obispo, Calif.) promoted its range of propellers for small airborne and underwater unmanned vehicles (UUVs) powered by engines of 100 hp or less. Most unusual was the company’s line of small injection-molded, glass-reinforced props, including a proprietary 50 percent glass/nylon 6.6 blade that incorporates a glass-fiber preform.
A number of composites manufacturers touted their capabilities as partner suppliers to UV OEMs. Notable among them was Vermont Composites Inc. (Bennington, Vt.). The company showcased its analysis, design and production capabilities for advanced composite UAS structures. The company, which supplies many Tier 1 defense contractors, including The Boeing Co. (Chicago, Ill.) and Lockheed Martin (Bethesda, Md.), is involved in the production of the Neptune UAS. Vermont Composites produces the vehicle’s fuselage for DRS Unmanned Technologies Inc. (Mineral Wells, Texas).
Also on hand was Applied Composites Engineering (ACE, Indianapolis, Ind.) to demonstrate its capabilities in composite part design and fabrication for UAS customers as well as composite tooling; repair; maintenance, repair and overhaul (MRO); and aircraft part manufacturing. ACE also has the capability to test radome parts, says the company.
EOS of North America Inc. (Novi, Mich.), a manufacturer of laser sintering systems and devices, emphasized in its booth several complex aircraft components made using polyamide and polyetheretherketone (PEEK) resin systems reinforced with glass and carbon fibers. Also in the EOS booth was Scott Killian, high-temperature laser sintering business development manager at Royal Engineered Composites (Minden, Neb.), which is using an EOS system to manufacture at least 180 PEEK-based parts that are being considered for use in the F-35 Lightning II.
Meanwhile, Solid Concepts (Valencia, Calif.) announced the development of CompositeCast, a composite material/process combination for medical device housing applications that features a glass, carbon or Kevlar fiber mesh laid on a silicone rubber tool. A vacuum is pulled on the closed mold, and urethane is cast on and around the mesh to produce the desired part. The cycle time for what Solid Concepts says is a typical part is about 190 seconds. Also new from Solid Concepts is GSL, a rapid manufacturing material that features a nylon base resin with glass and/or carbon reinforcement.
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