Military Tech

The race to develop an unmanned aircraft that can stay aloft for five years at a stretch has entered its second phase, where the prize is a $155 million DARPA contract to build a small-scale demonstrator model.

The project, called Vulture II, will pit three defense contractor teams--Aurora Flight Sciences, Boeing, and Lockheed Martin--against one another and the clock for the right to build a small-scale, working version of a high-altitude, electric-propelled UAV capable of remaining aloft and on station for three months.

The Vulture is expected to serve as an electronic sensor and military communications platform, and might eventually emerge as an affordable alternative to communications and reconnaissance satellites.

DARPA specs call for a 5-kilowatt power system and up to a 1,000-pound payload capacity. All three companies propose to power their aircraft with solar power during the day and batteries at night. These aircraft would operate above the clouds from 60,000 to 90,000 feet, and must be able to withstand jet stream-power winds typically found at those altitudes.

It may look like something your kids brought home from shop class, but this rugged, French-designed micro air vehicle (MAV) could be a missing link between smooth, steady hover and fast, forward flight.

The inventor, Dr. Jean-Marc Moschetta, professor of aerodynamics at the Institut Superieur de l'Aeronautique et de l'espace in Toulouse, France, created what he calls the MAVion with both commercial and military markets in mind.

A mere 30 centimeters long, the MAVion combines fixed wings with two counter rotating propellers, allowing it to operate with high aerodynamic efficiency--even in adverse conditions, according to the professor.

"The ultimate goal of the MAVion concept is to demonstrate a twofold capability using the same vehicle: fast forward flight and hover flight," Moschetta explained. "The two counter-rotating tandem propellers provide a simple means to enhance yaw control, which is particularly important in vertical flight."

"The global vision for developing the bimotor MAVion is to provide a fixed-wing aircraft that can be easily upgraded for hover, but also for rolling on the ground or along walls by adding wheels on either side," he said.

The project, funded by the European Office of Aerospace Research and Development in London and the French military, took top honors at the International Micro Air Vehicle Flight Competition held in Pensacola, Fla., this year.

The Excalibur, a new turbine-electric hybrid propelled VTOL (vertical takeoff and landing) unmanned attack drone, has successfully completed another test flight after taking on two new onboard computers last week.

Developed by Aurora Flight Sciences Corp. for the U.S. Army Aviation Applied Technology Directorate and the Office of Naval Research, the Excalibur is another radical robo-craft concept vying to fill the military's burgeoning demand for specialized UAVs.

The demonstrator model, weighing in at 700 pounds, can hit 520 mph, making it one of the fastest drones around, according to the Aurora. The nearly autonomous flight control system allows operators to concentrate on finding and engaging targets instead of piloting the aircraft, according to the Manassas, Va.-based company. The Excalibur's jet-borne vertical takeoff and landing and three electric lift fans providing attitude control and hover thrust, make it "runway independent." After takeoff, it flies like a regular turbojet.

The computers were supplied by Parvus Corporation from its COTS DuraCOR 820 line, a rugged, watertight 3-inch-high, 3-pound unit, featuring a conductively cooled 1.4GHz Intel Pentium-M processor and a solid state disk pre-loaded with a Linux or Windows XP Embedded operating system image. The system will handle everything from command and control to situational awareness, according to the Salt Lake City-based company.

There's no mistaking the mini-jet's intent. The full scale model is designed to carry a 400-pound weapon load; that would be four Hellfire Missiles.

The X-51A WaveRider is one step closer to its inaugural test flight later this year, now that airmen at Edwards Air Force Base have successfully "mated" the scramjet-propelled vehicle to a B-52 Stratofortress.

In December, an Air Force Flight Test Center B-52 is scheduled to papoose the X-51A to 50,000 feet over the Pacific Ocean before cutting it loose. At that point, a solid rocket booster from an ATACMS missile will fire up, accelerating the X-51 to about Mach 4.5. That's when the supersonic combustion ramjet kicks in, pushing the WaveRider to more than Mach 6 for up to five minutes, longer than all of its predecessors combined. NASA tests have reached Mach 9.6, or nearly 7,000 mph, according to some reports, but not for very long. The previous record was less than 10 seconds. Flight data will be telemetered back to Edwards Force Base before the X-51A test vehicle crashes into the Pacific.

A scramjet is an air-breathing engine that burns regular jet fuel, and may be the key to allowing airplanes to travel at speeds normally reserved for rockets. The engine requires no onboard oxidizers, but rather uses its own forward motion to compress air for fuel combustion. The X-51's chiseled nose allows it to "ride" shock waves that would pulverize a lesser craft. The X-51 was developed by Boeing and Pratt & Whitney Rocketdyne for the U.S. Air Force Research Laboratory and DARPA in order to "demonstrate a reliable system capable of operating continuously on jet fuel and accelerating through multiple Mach numbers."

"The heart of this aircraft is its engine," said Charlie Brink, X-51 program manager at Wright-Patterson Air Force Base.

"We're really breaking new ground in our understanding of hypersonic propulsion, but our four planned test flights will also enhance our knowledge of airframe-engine integration, high-temperature materials and other technologies. Together they will help us bridge air and space."

Future applications for the scramjet include access-to-space, reconnaissance and speedy, global strike capability.

As with landmines and napalm, cluster munitions are decidedly politically incorrect, and there is a concerted international effort to ban them. Problem is, they're highly effective, and countries that actually fight wars, like the U.S. and Russia, are loath to give them up.

However, a "humanitarian" version of the "cluster bomb" may head-off some objections to their continued production, or at least provide cover for those who want to keep them in the inventory. Billed as safer alternative to cluster munitions, Sensor fuzed weapons (SFW) contain independent self-destruct features based on altitude, time elapsed, and a battery "time-out" that shuts down all functions if no targets are detected within minutes of deployment, according to manufacture Textron Defense Systems. (Video)

"As responsible citizens, we share in the international community's concern about the need to limit the impact of war on civilian populations, particularly when the battle is over and hazardous unexploded ordnance remains," the company says. "We are committed to minimizing civilian losses during conflict and eliminating casualties when the fighting is done."

Cluster bombs are often seeded in the heat of combat, and then forgotten until, in what could be years later, some innocent hoeing his potatoes sets one off. They are generally large bombs that open in mid-flight to scatter dozens or hundreds of smaller sub munitions. In contrast, the SFW's self-destruct and self neutralization features ensure no unexploded ordinance is left behind, according to Textron.(PDF)

The SFWs contain Textron's BLU-108 sub munitions and Skeet warheads equipped with dual-mode passive infrared and active laser targeting sensors that use complex algorithms to detect targets over a lofted trajectory. If no target is detected, one or more of the three safety modes is activated. The first two enable the Skeet to self-destruct eight seconds after launch or within 50 feet above the ground. The third is a built-in redundant time-out feature that renders the weapon inert within minutes of hitting the ground.

While 98 countries have signed the Convention on Cluster Munitions, only 14 have ratified it; Japan being the most recent. Thirty are required for the ban to become legally binding. However, Albania and Luxembourg are on board, so it's only a question of time.

A new kamikaze drone out of Israel is designed to hang about overhead until it spots a target, then crash into it with "pinpoint accuracy" destroying the target, and itself, with 50 pounds of on-board explosives.

While classified as a Loitering Munition, the HAROP comes equipped with many of the usual UAV capabilities: high-performance FLIR and color CCD camera with 360-degree hemispherical coverage, allowing it to transmit video back to its operators just like a surveillance drone.

Like its predecessor the Harpy, the HAROP will be used to take out high-value targets such as air defense radars that transmit a strong pulse. But there's nothing to indicate it can't home-in on a cell phone call from a moving car. Fortunately, the developer, Israel Aerospace Industries (IAI), has thoughtfully included a Man in the Loop feature that enables the missile to be controlled in real time in case an attack needs aborting to avoid collateral damage.

The HAROP can be launched from a variety of platforms, including a ground vehicle. Launched out the box on a booster rocket, it unfold its wings, starts up an internal-combustion driven pusher propeller, and begins the hunt. Once a target is identified, it can crash "from any direction and at any attack angle, from flat to vertical which is highly essential in urban areas."

IAI has reportedly already signed a $100 million-plus contract to supply the lethal loiterers to an unidentified customer. Throwaway UAVs may do for IAI what disposable razors have done for Gillette.

Ubiquitous, reliable, and free to the public, the Global Positioning System (GPS) is now taken for granted, but don't dump those maps from the glove box just yet, since it's uncertain for how long the U.S. government can continue to deliver.

The US plans to invest more than $5.8 billion through 2013 to modernize and replenish the existing GPS satellite constellation. But facing cost overruns of $870 million and "significant" technical problems, the US Air Force, which is in charge of GPS acquisition, has struggled to build and deploy the next generation satellites on schedule, according to a Government Accounting Office report. A failure to complete development next year before old satellites begin to fail could have wide-ranging impacts on all GPS users, the report warned. (PDF)

Part of the problem has been an acquisition "reform" program, which instead of improving matters by placing more responsibility on the contractors, led instead to "requirements creep," relaxed specifications, late part delivery, test failures, and poor performance.

In addition, the program suffered from the "cluster" factor, i.e. a lack of management continuity. Diffuse leadership contributes to late delivery and cost growth. Part of the program has had seven different managers, the first five of whom only served one year each. The diverse array of officials and organizations involved made it difficult to pare back and control requirements, according to the GAO.

Then there were the mergers. For example, the aerospace and defense bits of Rockwell were acquired by Boeing shortly after it won a GPS contract. A year later, Boeing merged with McDonnell Douglas. The work was moved again. Next Boeing acquired Hughes Electronics' space and communications business, which meant another move; all the while shedding "valuable workers and knowledge."

Among the consequences of degraded GPS: more delays and cancellations on intercontinental flights, degraded 911 services and "smart bombs" get a little dumber. A decrease in accuracy of GPS guided munitions would force the military to use either bigger bombs or more of them to get the same bang. Can you say collateral damage?

Don't confuse this with what the hucksters are flogging at your local mall. This 15-gram "nano" copter goes where it's told and back again, indoor or out.

Prox Dynamics of Asker, Norway, has developed what it says may be one of the world's smallest unmanned helicopters. Now on its fifth prototype, the PD-100 Black Hornet has achieved a major milestone this month after successfully completing its first outdoor flight test. It's quiet, too. The sound from the helicopter was inaudible at three yards over ambient noise, according to the company.

"Prox Dynamics is very pleased to announce that the technological development of the PD-100 Black Hornet UAS is progressing according to plans," the company announced. The Hornet "can be carried in your pocket and launched within seconds to give immediate situational awareness. This new ultra small aircraft is a valuable tool in situations where a closer look at a hostile area or inside a contaminated building is crucial."

Although even smaller than a typical cheapo toy-copter, the Hornet is fully controllable, with the ability sprint from a dead hover to almost 20 mph. The secret behind it's stability is the micro control servos--"the smallest and lightest in the world, weighing less than 0.5 grams."

The company may market the "cigarette-packet-sized" mini-choppers in a three-pack weighing less than two pounds. The package will include a pocket controller and a charger. Delivery to select customers is expected later this year. Availability at the kiosk in the Galleria rotunda can't be far behind.

In what it says is a "first of its kind" initiative, the U.S. Navy plans to launch sometime this spring an unmanned aerial vehicle for a 24-hour endurance flight carrying a 5-pound payload and powered entirely by a hydrogen-powered fuel cell.

Called the Ion Tiger, the UAV can travel farther and carry heavier loads than earlier battery-powered designs, according to the Office of Naval Research. It also boasts "stealthy characteristics" such as reduced noise, low heat signature, and zero emissions (PDF).

"This will really be a demonstration for a fuel cell system in a UAV application," ONR Program Manager Dr. Michele Anderson said. "That's something nobody can do right now."

Fuel cells convert hydrogen and oxygen into water in a pollution-free process to create an electrical current delivering up to double the efficiency of an internal combustion engine, researchers claim.

The Tiger will use a "500-watt polymer fuel cell with a high specific power system." Weight will be reduced using high-pressure lightweight hydrogen storage tanks. The UAV has already "demonstrated sound aerodynamics, high functionality, and low-heat and noise signatures under battery-powered tests," according to ONR.

This test will show how a surveillance drone can operate economically with less possibility of detection and still exceed the duration of previous flights seven-fold.

Collaborators include Protonex Technology and the University of Hawaii.