Battle of the blimps

The military is driving a new renaissance in lighter-than-air-vehicles, writes Sharon Weinberger.

At the height of the insurgency in Iraq, Ed Herlik was working on an idea that he thought could solve the problem of roadside bombs – head into “near space”. The scheme involved putting a giant airship with sensitive surveillance equipment at a height of 18,000m (60,000ft) above the ground, allowing it to capture a 20km- (13-mile) radius birds-eye view of Baghdad.

The video might not stop someone from planting a bomb, the thinking went, but after the bomb went off (or perhaps found before it went off), the US military could use “backtracking,” or the ability to track where the bomber came from, and dismantle the bomb-making network. “Whatever happens would leave a video record that you can play backwards,” says Herlik.  “You can play the video backwards and forwards, and know everything about everybody.”

The idea of putting unmanned systems that would fly in near space for months on end was being championed by the Air Force chief of staff, but Herlik’s work on an omniscient near-space airship never came to fruition. His group was disbanded in 2005 when the Air Force leadership changed hands. But interest in lighter-than-air vehicles— from rigid airships and soft blimps, to tethered balloons and hybrid balloon-kites—remains strong in the military. Aerostats can be seen today flying over the US border with Mexico, along Israel’s turbulent border with Gaza, and even in central Kabul, where the US military keeps a watchful eye on possible Taliban activity.

Dirigibles and blimps have an almost retro charm to them that have long captured the hearts and imagination of aviation enthusiasts; in fact, lighter-than-air vehicles for surveillance is hardly new: Military balloons were used for surveillance in the American civil war, and the British and Germans both employed airships in World War I (airship nostalgia also has a dystopian association, best exemplified in the movie Bladerunner, where blimps urged people to go to the “off-world” colonies).

But the wars in Iraq and Afghanistan have given rise to a new renaissance of lighter-than-air-vehicles, and hundreds of aerostats have been sent to Afghanistan to help protect forward operating bases, while the US military is also funding more exotic propulsion-based airships for future use.

‘Bad guys’

All lighter-than-air vehicles – whether airships, blimps or balloons – work on the same principle: gas, whether helium or hot air, is used to provide lift. Then, once you have something that floats you can sling any number of components underneath, such as cameras for surveillance. While some lighter-than-air vehicles, like tethered aerostats, are free-floating, others, like blimps and airships, can be propelled and steered.

The basic idea behind such vehicles is appealing to the military: rather than using unmanned aircraft to conduct surveillance, which can be costly and have limited endurance, they could employ airships, or tethered aerostats, which can stay aloft much longer—weeks or even months—and do so at a fraction of the cost, at least in theory. Even beyond surveillance, the Pentagon has also looked at airships for moving cargo.

Aerostats, with their large visible bodies, also offer the potential to intimidate enemies, argue advocates.  “It’s tough to hide a large aerostat, over 100 feet long,” says Ron Browning, a business development manager for Lockheed Martin, which makes the Persistent Threat Detection System, a tethered aerostat that is flown over forward operating bases in Afghanistan.

Browning says Lockheed has even received anecdotal data from the US military that near one US base in Afghanistan, villagers would allow children to go out only when the aerostat was flying, believing it provided safety from the Taliban. “It has a visual deterrence effect,” says Browning. “When the bad guys sees the airship is up, they are not sure what it can it do, but they think if they can see it, it can see them.”

Aerostats aren’t just used in war zones; tethered balloons have long been used for border security, and some companies are also looking to expand their use to law enforcement. Lon Stroschein, the vice president and general manager of Aerostar International, which builds the Persistent Ground Surveillance System, another aerostat used in Afghanistan, says the police might be another potential market.

Aerostar has been working with the state of South Dakota to fund demonstrations of aerostats for local law enforcement: One of the company’s aerostats was used, for example, to keep tabs on visitors at a music conference in Sioux Falls. “They found kids who were lost, and linked them to parents,” he said, adding that the cameras also picked up images of teenagers “going into fields, areas they weren’t supposed to be.”

Kite runner

While tethered aerostats have rapidly proliferated over Afghanistan, the Pentagon has also been working on a next generation of lighter-than-air vehicles that would operate as airships, which can move from place to place. Such airships could be used to carry cameras, communication relay equipment, or even cargo.

Indeed, the list of airship projects is lengthy, if not always successful: Earlier this year, the Navy ended funding for the MZ-3, a propeller-driven airship that ended up lacking a clear mission, and last year, Lockheed Martin launched a massive airship from Akron, Ohio that was supposed to reach 18,000m (60,000 ft), but only reached 10,000, (32,000 ft) before coming down in a controlled crash. There was also Blue Devil II, an even bigger, 80m- (270ft-) long airship that was canceled earlier this year by the Air Force after it failed to meet its schedule and grew in price.

Yet some projects are still underway: Aeros International, a California-based company that traces it origins back to the Soviet Union, is currently working under a Pentagon contract to demonstrate a cargo airship that can lift 66 tons.   The barrier to building an effective cargo airship in the past has been a simple problem: helium gas is used to lift the aircraft, but as the weight (or cargo) is offloaded, the airship becomes lighter and will essentially float away.

The Aeros airship gets around this problem with an internal ballast control system, which works by compressing (and decompressing) helium stores in membranes around the airship’s rigid structure. “From an engineering standpoint it’s done,” says Aeros president Igor Pasternak, whose company is supposed to conduct a demonstration of its prototype next year.

The Army has also been funding the Long Endurance Multi-Intelligence Vehicle (LEMV), a hybrid airship that is expected to fly soon in Afghanistan and may cost over $500 million. The airship, which is designed to carry cargo and conduct surveillance, is supposed to have a maiden flight from a base in Lakehurst, New Jersey. Though the Army has released few details about the airship, which gets its lift from four diesel engines as well as helium, critics have doubted that its fuel will be sufficient to stay aloft for three weeks as claimed.

The Army, which has released little information about the vehicle, still won’t say when the first flight is supposed to take place. “The integration of components on the LEMV are near completion and engine testing is ongoing,” says John Cummings, a spokesman for Army Space and Missile Defense Command.

But if the idea of lighter-than-air vehicles is about making spying economical, then large airships costing hundreds of millions of dollars don’t make any sense, argues Sandy Allsopp, founder of the United Kingdom-based Allsopp Helikites, a company that produces a cross between an aerostat and a kite. While a helium filled balloon is pushed down by the wind (one of the biggest problems for aerostats), kites are pushed up. The helikite’s unique design, says Allsopp, allows it to fly in windy conditions that can force aerostats down, and the vehicle is cheaper and simpler to operate.

The US military is already flying the helikite in Afghanistan, but Allsopp believes their use could be expanded to blanket dangerous bomb-laden routes with cameras, making them safe for truck convoys.

In a war that has relied so much on relatively expensive equipment, like helicopters, and exotic technology, like drones, it may be ironic that the best solution could be something that looks like an elaborate kite. But Allsopp argues that his seemingly low-tech hybrid aerostat is precisely what is needed.

“Afghanistan is going to collapse like Vietnam, and we haven’t given the Afghans anything they are economically capable of keeping up,” says Alsop. “Our stuff is economical.”

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