Thứ Tư, 2 tháng 7, 2014

Why Old-School Airships Now Rule Our Warzones

PARIS, France — The Eurosatory military trade show here is supposed to highlight the latest in defense tech. Yet floating above the show was a representative of the oldest technology in military aviation, with a lesson even every modern general needs to heed.

This was a tethered reconnaissance balloon, as first used 220 years ago in the French Revolutionary War. It was one of the RT Skystar family, and differs from its 1794 precursor in that there is no nervous and exposed human in a basket with a telescope and a semaphore kit, just the kind of sensor package that you find on any small unmanned air vehicle (UAV). Power for the sensors flows up the tether and data flows down.

RT’s family—with payloads from 2.5 to 50 kilograms—are all much smaller than most U.S. aerostats and share some novel features. The gasbag is in two parts—a tough shell and a gastight bladder, the latter being designed to be discarded if it leaks. With a shape reminiscent of a Parisian breakfast roll, the envelope is stabilized in winds up to 40 knots by RT’s proprietary, wind-porous skirt. Launch and recovery, using a ring-shaped mooring device, is largely automated.

The main objective of the design is to cut down on manpower. Whether you take the military view and count boots and training hours, or whether you look at budgets, what often kills aerostats is the cost of people needed to unfold, inflate, launch, recover, deflate and fold the unwieldy beast, without ripping a hole in it.

The result is that RT now has 40 aerostats operational around the world, from Afghanistan to the World Cup arenas in Brazil. Users include the Singapore navy: What small-warship commander would turn down a 1,000-foot mast? The smallest version is backpack-able, the largest can carry a small radar, and all have endurance unlimited by fuel.

“Doing more with less” is often management-gabble to justify arbitrary budget cuts. “Doing less, with a lot less” can be a useful guide to writing military requirements. In a quote usually associated with Bill Stout, designer of the Ford Tri-Motor: “Simplicate and add more lightness.”

The U.S. Marine Corps seems to be following that principle in backing away from its long and fruitless quest for an armored infantry carrier capable of swimming at 25 knots. Originally framed as another run at that goal, following the failure of the Expeditionary Fighting Vehicle program, the Marines’ Amphibious Combat Vehicle requirement has been rewritten to call for something that can swim through the surf zone from a landing craft a few kilometers offshore, outside the reach of most anti-tank guided weapons.

One key to that change was on show at Eurosatory: Iveco’s SuperAV, an amphibious cousin of the company’s family of eight-wheel armored vehicles. The Marines found the SuperAV when they were looking for a cheaper complement to their fast amphibian, called the Marine Personnel Carrier. 

The MPC was supposed to be a simple river-crosser—either by fording of swimming. But in tests at Camp Pendleton in California, it turned out that the SuperAV, with two big shrouded propellers driven by hydraulic motors, and designed to use its eight wheels to steer and stabilize it in the water, could handle the Pacific surf zone as if it had grown up with The Beach Boys. Iveco is developing one version for Italy’s marines—and hopes for an order soon—and a larger, C-17 compatible model as a candidate for the U.S. Marines’ revised ACV requirement.

High mobility, small size and fewer people were a goal of another Eurosatory debutant, Elbit’s Spear mobile mortar: a 120-millimeter weapon on the back of a light four-wheel-drive vehicle. The technological secret sauce in this case is a new counter-recoil system that allows such a powerful weapon to fire without turning the vehicle upside-down or inside-out.

However, that would be no more than a party trick if it were not part of a system-of-systems aimed at the needs of special forces in a urban warfare—including a laser-guided mortar round, an electrically powered Skylark UAV with a miniature laser designator, and the communications systems to tie them all together.

The focus on cost and mobility has extended into missions such as ground-based air defense. While the big multinational Medium Extended Air Defense System has floundered along, and now needs to win some orders this year if it is to survive, a clutch of smaller systems from Britain, Germany, and Israel—all based to some extent on air-to-air-missile technology, and all deliberately “radar-agnostic,” able to work with any of a large number of modern multi-function radars—are making solid progress and gathering customer interest. It was one of those shows that make you think about change—and the value of stay lighter, and more competitive than your competitors. Suddenly, the ancient recon balloon seemed anything but outdated.

This column also appears in the latest issue of Aviation Week Space Technology. For more of Sweetman’s columns, see:

Why Old-School Airships Now Rule Our Warzones

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