Getting Ready for Reentry

The final meeting of the Mission Management Team (MMT) during Columbia‘s STS-107 mission was held on Thursday, January 30, 2003.

Everything seemed to be going well. The biggest headache was the continued degradation of the Water Pump Package, which was a crucial part of the heat exchanger on board the shuttle. A breakdown in the Spacehab module’s dehumidifier early in the flight, combined with the effects of the balky heat exchanger running, required the crew to actively manage the environmental systems in the ship to keep the cabin comfortable.

The crew, divided into a Red Team and a Blue Team, had completed most of their Spacehab work. A few final experiments were underway, while the results of others were being stowed for the return to Earth.

On the ground, the Structures Working Group was verifying that Columbia‘s weight was acceptable. At a projected “downweight” of 234,011 pounds (106,146 kg), Columbia would be the heaviest space shuttle ever to return from orbit.

Some people wondered if the extra weight—which could translate to extra heat during reentry—might overly stress the thermal protection system, if it had been damaged by the foam strike during launch. Someone even suggested tossing the Spacehab module overboard to reduce weight and heat. That drastic measure was neither possible nor taken seriously.

The MMT minutes showed that Kennedy Space Center was planning to gather the handheld cameras and external tank films as soon as Columbia landed. Someone would fly the cameras and films immediately—aboard the Shuttle Training Aircraft—to Marshall Spaceflight Center for analysis.

As on all other missions, an astronaut had been assigned to photograph Columbia‘s external tank as it separated from the ship right after the vehicle reached space. Such pictures were typically downlinked to the ground at the end of the first day’s operations. That never happened with STS-107. NASA never got to see how large the piece of foam was that struck the ship or exactly where it came from.

The handheld and ship-mounted cameras on Columbia became high-priority search targets during the recovery effort after the accident. Parts of one of the cameras that might have recorded the external tank’s separation were found on the shore of the Toledo Bend Reservoir. Neither the body of that camera nor its film were ever recovered.

The projected weather for February 1, landing day, looked good both at Kennedy Space Center and Edwards Air Force Base. Since Kennedy’s weather looked favorable for at least four days, the recommendation was made not to activate the Edwards landing team for the moment.

The MMT wrapped up its meeting. They agreed that no further MMT meetings were required during the mission.

In the back rooms, some engineers were still very worried. They kicked around worst-case scenarios. What if heat penetrated the landing gear wheel well during reentry? Could one or more tires be deflated? Could there be other damage that might threaten a safe return?

Next time: Landing Day

s107e05220-columbia-red-team-sleep
Columbia’s “Red Team” members prepare for their sleep period in the mid-deck bunks, January 20, 2003. From left: Laurel Clark, Rick Husband, and Kalpana Chawla. The unoccupied bunk is for Ilan Ramon, who was probably taking the photograph. (NASA photo S107E05220)

Author: Jonathan Ward

Jonathan Ward is an author of books on the history of American manned spaceflight. He also serves as an adjunct executive coach at the Center for Creative Leadership.

3 thoughts on “Getting Ready for Reentry”

  1. Was the heat penetration concern at the landing gear wheel well directly related to the foam strike, if so, was that concern directed at one specific wheel well? (the port side wheel well). Did the down-weight you mention factor into that wheel well concern directly/indirectly? Thank you!

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    1. The ascent video showed that the foam strike might have impacted somewhere near the left wing’s wheel well, so there was some concern that the door might have been compromised somehow. In fact, when the CAIB set up the “cannon” tests with the Southwest Research Institute, their first test was to fire foam at tiles mounted on a landing gear door. The downweight concern was not specific to the wheel well, but to both the structural consequences of landing such a heavy vehicle and on the overall heating effect during reentry. Columbia was already the heaviest orbiter, even without the Spacehab module. Hoot Gibson once told me that the tile surface was somewhat aerodynamically “rougher” on Columbia than the other orbiters, too, so she experienced somewhat higher heating during reentry than her lighter sister ships.

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