By Steven Profaizer Antarctic Sun staff

Construction crews working to complete NASA's new long-duration balloon facility have a longer drive to work.

The six buildings, which were built downhill from McMurdo Station during the winter, have been moved to their new home eight kilometers away at Williams Field.

Each of the buildings is on large skis designed to make them mobile. Starting in late September, the buildings were pulled one-by-one behind D-8 Caterpillar tractors in a slow parade to the airfield. The last one was put into place Oct. 14.

"This is a huge improvement to [the facilities] the program had," said Linda Waterhouse, project manager. "The buildings were old, and these are nice, new and bigger. It's exciting for [the scientists] because it means they can fly bigger payloads, and that's what it's all about for them - the science."

The buildings were constructed near McMurdo and relocated to Williams Field because of the advantages associated with conducting the large-scale project close to station. But they were originally designed to be mobile to save money and resources after the facility is in use.

"Historically, these buildings had to be dug out every year," Waterhouse said. "It took several weeks, a lot of people and a lot of money every year to dig them out."

At the end of the summer season, workers will be able to free the buildings from the locations where they are currently anchored and move them onto snow berms, where they will be re-anchored for storage. This will eliminate the need to excavate the buildings at the end of every winter.

Creating movable buildings by affixing them to permanent skis is not a new concept; airfields and research camps have used them for years. But the two largest buildings, at 12 meters high by 18 meters long, are in an entirely different weight class than structures typically moved by this method.

"We had a lot of people question whether we could move buildings this large, but we had done all the engineering analyses and felt we could do it," Waterhouse said. "We'd never moved anything that large before, but we had a lot of information to go on ... We drew on a lot of good historical information."

A reoccurring problem Waterhouse found in that history is that the skis will often freeze to the snow after sitting still and immobilize the building.

"People have used a lot of different methods to free the skis from the ice," Waterhouse said. "Most of them are pretty harsh and have a possibility of damaging the building, such as banging the building or putting explosives under the skis to break the bond."

Waterhouse said she wanted to come up with a less destructive and more effective way to free the buildings. Her answer was to create heated skis.

When it's time to move the buildings, the skis are warmed to melt the ice cementing the buildings in place. This frees them in a gentler way than many past methods afforded.

Frozen skis were not the only obstacle the team had to overcome. These buildings were largely constructed during the winter months, when weather is always a force with which to contend.

This winter was not the worst on record in McMurdo, but it was not an easy one, Waterhouse said. The buildings were erected outside, where the workers had to face months of dark winter days with temperatures dipping into the negative 70s Celsius.

"The largest challenge was probably constructing these buildings in the extreme weather conditions encountered during the winter," said Bill Marshall, construction coordinator for the project through the relocation of the buildings. "On average, the temperatures were [significantly colder than on station] and we got a lot of blowing snow. Most of the people were beat by [August]. Moving the buildings was probably the easiest part."