COLUMBUS, Ga. -- The horizon someday may be lined with giant floating orbs guarding people below from the enemy.
While it might sound quite sci-fi, a plant near the Army's Fort Benning plans to start producing unmanned spherical airships that resemble giant golf balls. They could be used to protect areas from terrorists and missile attacks, watch weather developments and perhaps even provide wireless telephone service to developing nations.
Interest in airships has grown in recent years, with nearly 20 companies developing them in the United States and Europe. Their advocates argue they are cheaper than satellites and manned reconnaissance aircraft and would fill a gap between the two.
"I've had requests from all over the globe for this technology. If I had 100 airships today, they'd all be sold," said Mike Lawson, president of Techsphere Systems International, which will build its spherical airships, ranging up to 300-feet in diameter, in Georgia.
Today's most visible blimps have company logos plastered on their sides and hover over major sporting events. They trace their heritage to the Navy blimps that provided surveillance for allied convoys crossing the Atlantic Ocean during World War II.
Now researchers are updating lighter-than-air technology for the 21st century with new power systems and fabrics to help them survive the stratosphere's extreme temperatures and intense solar radiation.
Floating about 13 miles above the earth and holding a stationary orbit for 12 to 18 months, they would provide more constant scrutiny than existing unmanned reconnaissance planes such as the medium-altitude Predator and the high-altitude Global Hawk that have to move around.
And unlike satellites, airships could return to earth for equipment upgrades.
Lockheed Martin Maritime Systems & Sensors already has a $40 million government contract to develop a high-altitude prototype in Akron, Ohio, home of the Goodyear blimps.
The giant aerospace firm, which has built more than 300 airships and thousands of tethered balloons known as aerostats since 1928, is sticking with the traditional blimp shape. But its 500-foot-long by 150-foot-wide prototype will be about 25 times larger than the Goodyear blimps.
Researchers at New Mexico State University's Physical Science Laboratory, which has more than 45 years of experience designing balloons for NASA and other government agencies, have proposed a futuristic wing-shaped balloon that would use wind currents to keep it in position without propulsion. It would operate at altitudes of about 100,000 feet and remain in position for three months at a time.
All the proposed airships would be unmanned and controlled from the ground or from satellites.
G. Guy Thomas, a science and technology adviser for the U.S. Coast Guard, said the lighter-than-air craft could carry equipment that would allow homeland security officials to detect approaching ships 500 to 1,000 miles from the coast.
"I know of five different programs out there looking at airships," he said. "I think we're going to see some in the not-so-distant future. We're going to try to team with some people to buy one."
John Robinson, managing editor of the Washington-based Defense Daily, said airships could provide additional intelligence for troops in Iraq who are being attacked almost daily by snipers and roadside bombs.
"I see this as a tremendous growth area because it's relatively cheap and it doesn't require a lot of people to operate," he said. "There's tremendous potential for the types of sensors you can put on."
A satellite costs the government about $150 million. Airship developers say their craft would cost considerably less.
Techsphere plans to build its spherical airships up to 30 stories high in Columbus, a Georgia city of about 186,000 along the Alabama border.
The company is using a design perfected over the past 21 years by airship developer Hokan Colting of Canada, who set a world airship altitude record of 21,000 feet last year in a 62-foot version. His design is maneuvered by propellers mounted around the sides.
Techsphere soon will establish a plant near Fort Benning, home of the Army's Soldier Battle Lab, and plans to build another plant to accommodate its largest airships. Georgia Institute of Technology researchers will develop a propulsion system, possibly using solar panels and fuel cells, to power the propellers during missions of a year or more at 65,000 feet.
"Our high-altitude airship program is well on its way," said Lawson, who hopes to deliver his first ship next year.
Airships date back to 1783, when a French chemist flew the first manned hydrogen-filled balloon over Paris. Lockheed Martin began building helium-filled blimps for the Navy in 1928. The Germans offered trans-Atlantic flights on its luxurious hydrogen-filled Zeppelins until 35 people died in 1937 as the majestic Hindenburg erupted in flames while docking at Lakehurst, N.J.
Interest in airships has continued, despite the Hindenburg disaster, said Tom Crouch, a senior curator at the Smithsonian Institution's National Air & Space Museum.
"There's always been a desire to bring them back, to find an economic niche," he said.
On the Net:
Techsphere Systems International: http://www.techspheresystems.com/
New Mexico State University: http://www.nmsu.edu/
Lockheed Martin: www.lockheedmartin.com