Heat rose off the Manassas tarmac in waves, bathing the reenactors of wars gone by in sheets of sweat that soaked through their camouflage fatigues and thick wool uniforms.

Most shrugged off the drippy discomfort, rationalizing that sweat is a natural part of war. And yet there was no battle being staged yesterday at the small airport, no skirmishes or pyrotechnic displays meant to wow the crowd. Instead, the actors and a host of vintage tanks and planes are part of a larger living history lesson being sponsored this weekend by the fledgling Freedom Museum.

Organizers hope their three-day festival, which ends at 5 p.m. today, will pay tribute to those who served freedom's cause and help introduce the region to the area's newest history museum, which has found temporary housing for its start-up exhibits inside the Manassas Regional Airport terminal building.

"This is just a glimpse of our vision," said museum President Chuck E. Colgan Jr., an Army photographer during the Vietnam War, who is spearheading the project. Colgan and other planners hope to build a facility that honors 20th-century American soldiers and creates a lively portrait of America's military history from the Spanish-American War in 1898, which positioned the United States as a global power, through the recent NATO campaign in Yugoslavia.

"We want to tell the story of the century," Colgan said, surveying the hundreds of photographs, posters and colorful vignettes of the century's war heroes and heroines, displayed inside the terminal building. "We could have a world-class facility built here in two years."

Colgan hopes to secure a permanent home for the facility on a piece of land adjacent to the airport and to attract federal and state funding to create a $15 million museum and visitors center. Planners want to create a museum that would incorporate aircraft and armored vehicle demonstrations.

A site near the Manassas airport would allow the museum to use the airstrip, provide enough land to house and display dozens of planes and vehicles and would be aligned with the state's much-traveled history corridor, from Leesburg to Williamsburg.

"We envision this as the first place people will come before they go visit everything else," said retired Marine Corps Col. Avery Chenoweth, the museum's executive director. In an area that is rife with museums and memorials, Chenoweth said the Freedom Museum is designed to give visitors a view of 20th-century military history that is more comprehensive than other institutions. "They don't tell the whole story and put it together as we're going to do."

Charlie Williams, 51, a former Navy commander and his 11-year-old son, Ben, spent the better part of the morning touring the exhibits and talking with reenactors. Clutching posters and a bag of souvenirs, Ben, a self-confessed fan of military history, said he's solidly behind the addition of a museum in Manassas.

"I've learned a lot about the history of America and other nations," he said, turning to his father who added, "We've seen a lot of people out here very interested [in the displays], and for the older people, it obviously brings back a lot of memories."

The Prince William County government has chipped in $100,000 for the project and the State of Virginia has given an additional $75,000. Combined with other donations, the museum, which was unveiled July 4, has assets totaling about $300,000.

The Freedom Museum is on a short list of potential sites for a Virginia military history museum being studied by the Virginia Department of Conservation and Recreation.

The festival continues from 9 a.m. to 5 p.m. today. Admission is free. There is a $3 charge to enter the tarmac and an additional charge to tour some aircraft. The museum is open from 9 a.m. to 5 p.m. every day.

CAPTION: A line of people wait on a hot tarmac to walk through a B-17 on display over the weekend at the Freedom Museum at the Manassas Regional Airport.