NASA is already setting into motion efforts to improve the external tank's spray-foam insulation, which broke off on launch and may have damaged the orbiter.
It is also studying the feasibility of inspecting and repairing damaged thermal protection tiles in orbit. And it wants to improve its photographic capability on launches to monitor for debris damage. Those programs alone could cost hundreds of millions of dollars, if not more, experts say.
The board is not itself conducting the bulk of the investigative work.
The Federal Emergency Management Agency is taking the lead in the hunt for debris, which will continue undiminished through the end of April, according to Scott Wells, the coordinator of the effort. Wells said the search and recovery of debris alone is expected to cost $302 million, about triple the amount spent on the Challenger search.
The agency is operating four base camps in Texas, each with 1,000 paid employees who are spending each day conducting searches on foot and spending nights camped in tents. Most of the workers are part of a firefighting effort organized by the U.S. Forest Service and various state agencies.
Wells said the plan is to search by foot a corridor 240 miles long and four miles wide along the center line of the shuttle's flight path. Standing 10 feet apart, the investigators are walking and visually searching about 1,000 square miles of Texas.
About three dozen aircraft are searching an additional 1,500 square miles a few miles farther from the center line of the flight path. And divers are searching lake bottoms for dozens of pieces of debris identified by Navy sonar experts. So far, the hunt has located 28,000 pieces of wreckage.
The EPA has dispatched 700 staffers to help deal with any hazardous materials, which include the toxic fuels Columbia carried in its various thruster and rocket systems.
Boeing Co., which built the shuttle and provides engineering services for it, has roughly 1,000 employees detailed to the investigation, assisting with aerodynamics analysis and debris location, according to spokesman Dan Beck. "Wherever there is expertise needed by the [investigation board] or NASA, we are providing it," he said.
USA, the private contractor that prepares the shuttles for launches and assists with almost all aspects of flights, has 300 employees assigned to the investigation and others that have provided temporary help, said company spokesman Michael Curie. USA has about 10,300 workers, though some of the employees assist with other programs such as the international space station.
