As federal investigators surveyed the scene, one man remained in critical condition Thursday after a hangar collapsed at the Paulding Northwest Atlanta Airport.

The contractor worker, whose name was not released, was one of two people injured when the hangar, still under construction, fell Wednesday afternoon, according to the Paulding County Fire Department. The two men, both contractors from outside of Paulding County, were on top of the hangar when it collapsed, Blake Swafford, the airport director, told the AJC on Thursday afternoon.

One man, Swafford said, was able to hold on to part of the building as he fell. But the other, the man who remains in critical condition, fell to the ground, Swafford said.

The man with minor injuries was treated at WellStar Paulding Hospital and released, MaryAnn Phipps, spokeswoman for the fire department, told the AJC. The other remained in critical condition at WellStar Kennestone Hospital in Marietta, Phipps said.

Investigators from the Occupational Safety and Health Administration were at the airport Thursday trying to determine what may have caused the collapse, a spokeswoman for the airport said. Wind may have been a factor in the collapse, Swafford said.

Swafford said the hangar construction likely will be delayed about a month and, hopefully, will be completed this summer. It's the second major delay for the project, which was previously delayed because the concrete slab was not level, Swafford said. The slab wasn't believed to have caused the collapse, he said.

When it opened in 2008, the Paulding airport was the first jet-ready airport to open in Georgia in more than 30 years. It is located about 30 miles northwest of Atlanta, near Dallas.

In October, the Salute America 2012 Air Show is planned at the airport.