Michael Leinbach - Bringing Columbia Home - The Untold Story of a Lost Space Shuttle and Her Crew

The MMT members convinced themselves there was nothing to be overly concerned about for Columbia ’s reentry. Rather than digging into the possibilities of what could go wrong, they reassured one another that everything would be all right.

“Prove to me that it’s not safe to come home” demonstrates a very different management culture than does “prove to me that it is safe to come home.” The former attitude quashes arguments and debates when there is no hard evidence to support a concern. It allows people to talk themselves into a false sense of security. The latter encourages exploration of an issue and development of contingencies.

In hindsight, many of us who participated in the debate and decisions—myself included—blamed ourselves for not pressing the issue about the foam strike. However, it simply did not occur to most of us at the time that the crew might be in danger. Complacency and past experience lulled us into believing that the shuttle would get her crew home safely—just as she had done more than one hundred times previously—despite the knocks and dings. Management assumed that if there really were a problem, the “smart people” who were looking at it would speak up. Managers seemed not to comprehend that objections had in fact been raised and then brushed aside. Pressing on with the mission so that NASA could get back to space station assembly flights just seemed like the right thing to do.

The crew was not even told about the foam strike until January 23—one week into the mission—and then only to prepare them for a question that might arise in an upcoming press conference. Mission Control sent an email to Rick Husband and Willie McCool informing them about the hit and immediately downplaying any worries: “Experts have reviewed the high speed photography and there is no concern for RCC or tile damage. We have seen this same phenomenon on several other flights and there is absolutely no concern for entry.” [3] Steve Stitch, email message to Rick Husband and Willie McCool, subject “INFO: Possible PAO Event Question,” January 23, 2003, www.jsc.nasa.gov/news/columbia/107_emails/foamemails.doc .

Even if the astronauts had been asked to look for damage, they could not have shed light on the situation without taking extraordinary measures. Most of the front of the wing was not visible from the windows in the cockpit. The orbiter was not carrying its robotic arm in the payload bay, because the arm was not needed for this mission. Had that arm, with its multiple television cameras, been available, the crew could have scanned the top and front of the wing for damage. Even so, the arm would not have been able to reach underneath the orbiter to look for damage there.

The only other way the crew could have checked the wing for damage would have been to take a space walk. That would have required a two-day interruption to the science activities in Spacehab. The pressurized tunnel to Spacehab was on the other side of the air lock in the crew compartment. The crew would have had to seal off Spacehab while preparing for and conducting the space walk.

So, the MMT did not ask the crew to inspect the orbiter. The MMT incorrectly concluded that no significant damage existed. Besides, the MMT reasoned, there was nothing the crew could have done about it anyway. The MMT flatly declared that there was no “safety of flight” issue involved—that is, no risk for reentry. Any damage to the thermal protection system would just be a turnaround maintenance problem for the next mission once Columbia was back on the ground.

The US Air Force’s Maui Optical and Supercomputer Site (AMOS) took images of Columbia as it passed over Hawaii on January 28. The orbiter’s payload bay was facing the cameras on the ground. The Spacehab module was clearly visible in the payload bay. Unfortunately, the open bay doors obstructed the view of the front half of Columbia ’s wing, where the foam was thought to have struck the ship. The resolution of the AMOS cameras was probably not good enough to have captured wing damage anyway.

That same day—the seventeenth anniversary of the Challenger accident—Rick Husband and his crew paused to remember the crews of Challenger and Apollo 1. Husband said, “They made the ultimate sacrifice, giving their lives in service to their country and for all mankind. Their dedication and devotion to the exploration of space was an inspiration to each of us and still motivates people around the world to achieve great things in service to others. As we orbit the Earth, we will join the entire NASA family for a moment of silence in their memory. Our thoughts and prayers go to their families as well.” [4] Evelyn Husband and Donna VanLiere, High Calling: The Courageous Life and Faith of Space Shuttle Commander Rick Husband (Nashville, TN: Thomas Nelson, 2003), 163.

Unknown to NASA at the time—and even to the people manning the intelligence assets that acquired the images—the US military had inadvertently obtained evidence of something breaking away from Columbia on the second day of her flight.

The Space Surveillance Network (SSN), which was operated jointly by the US Army, Navy, and Air Force, was a worldwide network of sensing systems designed to track objects in orbit around Earth. Early in the postmortem of the Columbia accident, SSN analysts went back over their tracking data to see if they had obtained any information about Columbia and any objects that might have collided with her in orbit. The analysts noticed that another object was in the same orbit as Columbia beginning on the second day of the mission.

After refining the radar data, the analysts determined that a slow-moving object, about the size of a laptop computer, gradually drifted away from the shuttle. Its slow motion implied that it was probably not a piece of space junk or a meteor. Further tests showed that the radar properties of the object were a close match for a piece of RCC panel—possibly part of the wing’s leading edge. It appeared to separate from the shuttle after several thruster firings that changed Columbia ’s orbital orientation.

Whatever it was, the object reentered the Earth’s atmosphere and burned up on January 20, twelve days before the end of Columbia ’s mission. Theories about the object and its origin were debated at length during the accident investigation, but its exact nature and possible relevance to Columbia ’s demise will never be known.

Again, no one knew anything about this object during the mission. Could this information have changed the course of events? That will also never be known.

As Columbia approached the end of her time in orbit, some people at KSC began to worry about how to bring her home safely. If the thermal tiles had significant damage, Columbia would need to keep its temperature down as much as possible during reentry.

Weight was an immediate concern. As the first ship in the fleet, Columbia was already heavier than her sister shuttles. The added mass of the Spacehab module meant that STS-107 would be the heaviest shuttle ever to return from orbit. That would make her reentry hotter than usual, even if everything went as planned.

Some people at KSC openly asked, “Can we jettison the payload to make the vehicle lighter?” Even if that were possible—and it was not—it would have meant the loss of many of the science experiments and their data. Management did not seriously consider the recommendations to throw overboard all “loose objects” in the crew module and Spacehab, especially with the official determination that there was no concern for flight safety. [5] A study managed by LeRoy Cain subsequently determined that even if it were possible to jettison the payload bay contents and unneeded consumables on the ship, the maximum temperature reduction on the wing leading edges was at best only 7 percent (“Entry Options Tiger Team,” NASA Mission Operations Directorate, Flight Director Office, April 22, 2003).