CAPE CANAVERAL, Fla., March 31 (UPI) -- NASA engineers questioned a Boeing analysis that provided the foundation for an apparently false sense of security shuttle Columbia would return safely from space, internal documents released Monday show.
The analysis was conducted after videos of Columbia's launch revealed foam insulation from the shuttle's fuel tank coming off about 81 seconds after liftoff and striking the underside of the left wing. The shuttle disintegrated over east Texas 16 days later as it attempted to re-enter Earth's atmosphere for landing. Seven astronauts died in the agency's second fatal shuttle accident.
After Boeing presented its findings, the head of the Johnson Space Center's structural engineering division was disturbed enough to write: "The meeting participants ... all agreed we will always have big uncertainties in any ... analysis and ... test data until we get definitive, better, clearer photos of the wing and body underside.
"Without better images it will be very difficult to even bound the problem and initialize thermal, trajectory and structural analyses," writes Rodney Rocha, in an e-mail to colleagues Jan. 21 -- the fifth day of Columbia's mission.
"Their answers may have a wide spread, ranging from acceptable to non-acceptable to horrible, and no way to reduce uncertainty."
"Can we petition (beg) for outside agency assistance," continues Rocha. "Some of the old-timers remember we got such help in the early 1980s when we had missing tile concerns."
A day later, apparently upon hearing NASA managers were not requesting satellite imagery of the shuttle to try to determine the extent of damage from the foam impact, Rocha drafted the following memo:
"In my humble technical opinion, this is the wrong (and bordering on irresponsible) answer," from the space shuttle program "not to request additional imaging help from any outside source. I must emphasize (again) that severe enough damage ... combined with the heating and resulting damage to the underlying structure at the most critical location ... could present potentially grave hazards.
"Remember the NASA safety posters everywhere around the site stating 'If it's not safe, say so?' Yes, it's that serious," wrote Rocha, who was unavailable for comment Monday.
Managers cleared the shuttle of flight safety concerns and declined invitations to use spy satellites to image the shuttle in orbit, deciding the Boeing analysis predicted correctly the vehicle was not seriously damaged by the foam impact at launch. However, in the thousands of pages of e-mail messages, memos, viewgraphs and other documents released under the Freedom of Information Act late Monday, are copies of Boeing's own conclusions that its data were uncertain.
For example, Boeing acknowledged the "flight condition is significantly outside of test database" and that a "small variation in energy input could substantially increase damage."
The panel given the task to find the cause of the accident has ordered lab tests to determine the true effect of a 1- to 2-pound chunk of foam insulation slamming into various parts on the wing. Three-dimensional video of the debris hit painstakingly pieced together for weeks after the accident show the foam striking the leading edge of the wing, a scenario that was not the focus of the Boeing analysis.
From the e-mail messages, NASA clearly was expecting Columbia to land safely, with engineers making plans and issuing requests for measurements and pictures of the actual wing damage after the shuttle's return to Florida.
Falling foam insulation had struck orbiters several times on previous launches, but the debris was never as large as what was shed from Columbia's tank.
NASA already had been planning to make changes in the foam application or manufacturing process when the Columbia accident occurred. The investigation board has not yet determined what effect, if any, the foam debris strike had on the shuttle's demise, but it has remained a leading theory throughout the two-month-long investigation.