In the middle of a cornfield in Maryland, a blimp glided in for a landing.
Eight men grabbed two long guide ropes that dragged them along, their heels dug in, until the blimp halted, hovering a foot off the ground. The sun momentarily dimmed as the airship's two propeller engines kicked up a swirl of dry corn husks.
The U.S. Army believes scenes such as the one that has unfolded repeatedly over the past two days near Freeway Airport in Bowie might be as much about the future as a quaint reenactment of a bygone time.
That is why the Army has leased a blimp from the nation's only airship manufacturer and outfitted it with sensors and cameras. Over the next week, the 178-foot-long lighter-than-air craft will conduct test runs over the Washington area. In the fabric gondola hanging below the envelope, a technician will aim a camera, mounted to the front of the cabin, at government buildings and military bases.
The tests are designed to determine how effective the electro-optical and infrared cameras are at detecting potentially threatening movements on the ground when attached to a blimp yawing in the heat currents as it floats along 1,000 feet in the air at 30 knots. The equipment already is used in Iraq and Afghanistan to identify enemy troop movement, but in combat zones it is attached to a static inflatable device that looks like a giant, blimp-shaped balloon.
The prospect that a helium-filled blimp is an idea whose time has come again is increasingly being considered by serious people charged with defending troops overseas and the nation's borders at home.
Among the interested agencies is the Department of Homeland Security. Unmanned drones are already used along the border with Mexico. The agency thinks blimps might be equally useful.
"We're doing a preliminary evaluation," said Chris Wells, an assistant chief with the Border Patrol. "Though it's old technology -- airships have been around for a number of years -- recent advances caused us to take a fresh look at it."
Aboard the blimp, Phillip Mix, an electronics technician with Crane Naval Service Warfare Center, sat before a television screen as the airship cruised above Route 50. The camera beamed images from 800 feet below -- shopping malls, woods and meadows. Mix said that on a clear day, the cameras can discern objects from six to seven miles away.
Although the technology is state-of-the-art, blimps have been used for military force protection for decades. During World War II, more than 150 blimps patrolled the East Coast on anti-submarine missions, escorting convoys out to sea.
From a blimp, it was possible to see a periscope in the ocean, said Norman Mayer, an Alexandria resident who is president of the Naval Airship Association.
"There was never a convoy lost while an airship was patrolling," Mayer said as he waited in the cornfield to board. A former Naval blimp pilot and semi-retired aeronautical engineer, Mayer has spent his career designing and consulting about blimps. He allows that whenever he mentions his calling to a new acquaintance, "They want to have me psychoanalyzed."
Fewer than 30 blimps are in use, and 19 of them were made by the American Blimp Corp. in Oregon, one of only a handful of companies making modern blimps. Another is a German company whose name is synonymous with dirigibles, Zeppelin, which has sold three in recent years, all for sightseeing.
American Blimp makes three sizes of blimps, which sell for $2 million to $4 million each. Most are used during sporting events.
"It's a fun business," said E. Judson Brandreth Jr., the company's vice president for marketing. "Goodyear did a study and found that universally, blimps give people a big warm fuzzy. People just like blimps."
Brandreth said American Blimp is promoting the use of airships as airborne surveillance. Many people wrongly assume blimps are vulnerable to bullets fired by, say, drug runners or terrorists.
"Almost everything people think they know about blimps is wrong," said Brandreth, citing the misconception that a bullet can bring down a blimp. The envelope is rip-proof. And many people seem to consider blimps moving targets.
"We often discover bullet holes when the airships are brought to our hangar for maintenance," he said. "People shoot at them. Particularly in the country. We think it's kids, not urban warfare. We just patch it up and go."
Pilot Jim Dexter emphasizes how safe a blimp is as he guides the airship above Maryland suburbia.
The blimp takes off and lands at a 30-degree angle, though it feels steeper. The eight seats come equipped with seat belts. Several gondola windows are open, and gentle breezes waft through and lift loose-fitting shirts in billows.
The ride gives the sensation of floating. Dexter works the elevator wheels beside his seat to adjust for the hobby-horsing caused by rising heat currents.
Dexter, who trained to fly fixed-wing aircraft but found airships were his passion, has flown during winds so strong that his blimp was blown backward. Like most blimp aficionados, he gets tired of the 1937 Hindenberg disaster being mentioned. The airship was filled with hydrogen, not helium, and caught fire because the paint contained a compound used in rocket fuel, Brandreth said.
"The Hindenberg always comes up, over and over," he said with a sigh. "If the engines quit, it's a balloon; you vent the helium, go down and land. If there's a rip in the envelope, you let the helium out and recover it later. It's a very safe aircraft."