Combat Troops Pitch a New Generation of Field Shelters.

As the Army rushes to transform itself into a more rapidly deployable force-and at the same time, offer its troops in the field a few more creature comforts-soldiers are beginning to see major innovations in one of the very oldest pieces of military equipment, the tent.

Warriors have relied upon tents for temporary shelter at least since Old Testament days, when, according to the Book of Genesis, Abraham's nephew, Lot, "pitched his tent toward Sodom."

Since those times, tents have changed only slowly, especially those used by military forces. The standard field shelter for the U.S. Army, for example, is still the General Purpose (GP) tent, which was issued during World War II.

But that is changing, according to Frank Kostka, team leader of the 21st Century Fabric Structures group, at the Soldier Systems Center in Natick, Mass. The GP-which is leaky, bulky, dark on the inside, floorless and vulnerable to pests-is being replaced by the Modular General Purpose Tent System (MGPTS), Kostka said. Eureka Tents, of Binghamton, N.Y, last year received a $5 million contract to begin initial production of the modular shelters.

Like the older versions, the modular tents can be used for troop billeting, command and control, humanitarian or disaster relief, storage or maintenance functions, Kostka told a recent briefing of defense executives in Sparks, Nev.

The modular rents are constructed with a vinyl-coated fabric-rather than canvas- and they are white on the interior, making them much brighter inside, Kostka said. Seams are heat-sealed, not sewn, to form a waterproof barrier, he explained.

Screen walls are designed directly into the new tents, so that the solid fabric walls can be rolled up for better ventilation in hot weather. The old GP tents require separate screen liners. Units that deploy without them-as was the case during Operation Desert Storm-have no choice but to open the walls, leaving the inside vulnerable to the elements.

Unlike the older models, modulars have floors that extend several inches above the ground and wrap up, around the bottom of the walls, to keep out rain and other undesirables, such as insects, rodents and snakes.

The modular shelter is larger. Both versions come in small, medium and large sizes. The old GP medium is 16 feet wide, 32 feet long rind 5.5 feet tall at the sidewall. The modular medium measures 18 by 36 by 7. This, Kostka said, provides additional headroom along the interior sides of the tent.

The new tents also are faster to erect or strike, he said. Four soldiers can put up or take down a modular in less than 30 minutes, compared to five soldiers and 45 minutes for the older model.

Additionally, the modular tents, unlike older models, can be extended in 18-foot increments. Each doorway can be attached to the Army's Tent Extendable Modular Personnel (TEMPER) vestibule.

This gives Army units considerable flexibility to design tent layouts to meet their specific needs, including space, configuration and regional weather conditions.

In addition to space for sleep and work, modular tents can be configured to provide all of the shelter needs of large numbers of troops in the field, such as dining, laundry, latrine, showers, health, worship and recreation. They can be heated in the winter and air conditioned in the summer. The recreation tent can accommodate a 52-inch television screen, VCR, satellite dish, table tennis and weight room.

With these shelters as building blocks, the Army plans by 2005, to develop 36 rapidly deployable "tent cities," known as Force Provider units, and to preposition them in Europe, the Persian Gulf, the Western Pacific and the continental United States. A total of 27 of the units already have been completed. Each module is intended to support 550 personnel or more, and each comes with its own water and fuel-storage, power-generation and distribution and waste-water-collection systems.

Force Provider units are meant to serve as forward-deployed base camps that can be assembled quickly, Kostka said. They can be used as theater-reception facilities, intermediate staging areas, rest and refit complexes and sites for humanitarian and disaster-relief operations.

A typical camp requires approximately 10 acres of land. Site preparation rakes about three to four days. The entire camp can be operational within 14 days or less.

To perform field maintenance on large pieces of equipment, such as helicopters or tanks, the Army is developing large shelters that don't need center poles to hold up the structure.

The service is working with Vertigo Inc., of Lake Elsinore, Calif., to build large maintenance shelters using "airbeams"-durable, inflatable frames, which support the tent's skin, leaving the entire interior unencumbered for more flexible use.

Airbeam technology grew our of the work that Vertigo was doing to help develop the Army's latest generation of parachutes (See page 44).

"Airbeams are manufactured by braiding a high-strength, three-dimensional fabric sleeve over an air-retention bladder," according to the firm's president, Glen Brown. They are deployed by inflating them to 65 pounds per square inch.

Airbeams have been used to build a Large Area Night Maintenance Shelter (LANMas), which was big enough to house a UH-60 Blackhawk helicopter, Brown said.

Current maintenance shelters have heavy metal frames and rake up to 10 days to set up, Kostka said. LANMas, on the other hand, can be erected in four hours, he said.

"The biggest reason that airbeams are exciting to us is the reduced logistical footprint," Kostka said. "All anybody wants to know these days is, 'how many C- 130 pallets does it take?' And airbeams are comparatively light."