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

Rick replied, “We appreciate it, Mike. The Lord has blessed us with a beautiful day here, and we’re going to have a great mission. We’re ready to go.”

I gave the “Go” for the count to pick up on schedule.

The fighter pilot had assured me there was no visible threat, but the internal voice of doubt nagged me.

God—what if I’m wrong?

The final minutes of the countdown quickly ticked away, and all went smoothly. I nervously looked out the window toward the launchpad every few seconds, half expecting to see something heading toward Columbia .

At the launchpad, everything was proceeding exactly as planned. A few seconds before 10:39 a.m., Columbia ’s three main engines ignited and quickly built up to steady thrust. Columbia ’s nose rocked forward several feet in reaction to the off-center impulse from the engines and buildup of thrust two hundred feet below. The instant the shuttle rocked back to vertical again—6.6 seconds after main engine ignition—the twin solid rocket engines fired. Explosives shattered the hold-down bolts at the same moment, and Columbia leaped into the clear blue sky. Launch and Entry Flight Director LeRoy Cain at Mission Control in Houston assumed control of the mission as soon as the solid rocket boosters fired.

I breathed a deep sigh of relief.

The families filed back into the LCC after Columbia disappeared from sight about two minutes after liftoff. Eight and a half minutes after launch, Columbia was in orbit. It seemed to be a picture-perfect launch.

After the postlaunch checklists were complete, the launch team and I went to the lobby of the Launch Control Center for the celebratory meal of beans and corn bread, which was served after every successful launch. Still too on-edge to eat, I took a quick bite and shook hands with a few folks on my way to another tradition—the postlaunch press conference. Fortunately, no one else present there knew about the security incident. And they didn’t need to know.

It was later determined that the unidentified object on radar was a cluster of Mylar party balloons with a small, empty metal box—about the size of a clock radio—dangling underneath. Riding on the winds, the balloons dipped into and out of radar coverage. They were found two days later on the shore of the Banana River approximately five miles south of the launchpad.

Once Columbia ’s main engines shut down, the flight computer commanded pyrotechnic charges to fire to jettison the external fuel tank. Astronaut Mike Anderson triggered cameras on the shuttle’s belly to take photos of the tank as the shuttle pulsed its maneuvering thrusters to move away. Those photos were part of the launch documentation, to note any issues that might require attention on the next missions. The crew did not notice anything unusual about the tank as it slowly drifted away from them. As usual, the tank would break up and fall into the Pacific Ocean south of Hawaii.

Standard procedure called for the tank photos to be transmitted to the ground at the end of the first day’s operations. However, the Columbia crew had a busy day ahead of them configuring the experiments aboard Spacehab.

The photos of the tank were never downlinked.

If engineers on the ground had seen the photos, they would have immediately noticed that a large piece of foam—about the size of a carry-on suitcase—was missing from the area at the base of the left side of the strut connecting the orbiter’s nose to the tank.

Back on the ground, an array of cameras along Florida’s Space Coast had filmed Columbia on her ride uphill. The imagery analysis team at KSC began reviewing the films the afternoon after the launch. The team was frustrated to discover that one of the tracking cameras had not worked at all, and another was out of focus.

What particularly caught their eye, however, was footage from one camera showing what appeared to be a large piece of foam falling off the tank 81.7 seconds into the flight. It fell toward the Columbia ’s left wing and then disintegrated into a shower of particles. The foam had clearly struck the orbiter, but it was impossible to tell from the images exactly where it had impacted or how bad any damage might be.

Ann Micklos, who represented her thermal protection system team during the video review recalled that “people’s jaws dropped. You could have heard a pin drop in that room when we saw the foam strike. We watched it on the big screen again and again and again, trying to understand where the foam impacted the orbiter.”

It was indeed an impressive-looking impact, but debates about its severity began almost immediately. Was this a serious situation? Or was it like all the other impacts—posing a maintenance inconvenience but not a threat to the crew? The imagery lab in Tower K of the Vehicle Assembly Building went to work to enhance the video as much as possible.

Why is foam shedding even a concern? To understand that, we need to review the vulnerability of the shuttle’s design. The shuttle’s flexibility was ironically its biggest downfall. Unlike previous spacecraft designs for Mercury, Gemini, and Apollo—in which the capsule with the astronauts was at the front end of the rocket—the space shuttle and its crew rode into orbit beside the propellant tank and the rocket boosters. This meant that ice or other debris could fall off the tank and boosters and strike the shuttle during ascent. Damage from launch debris was one of NASA’s major headaches, as there was no way to repair an orbiter’s exterior surfaces once the vehicle reached orbit.

We did not want to put a wounded space shuttle into orbit if we could avoid doing so.

Chief among the concerns was the intricate heatshield system completely covering the orbiter. The shuttles had aluminum skin, and when “naked,” they looked remarkably similar to conventional aircraft. However, aluminum has a relatively low melting point and cannot withstand the blazing temperatures of reentry. NASA’s ingenious heatshield for the shuttle consisted mostly of a system of silica tiles, which not only insulated the vehicle’s structure, but actually radiated heat away from the shuttle. The tiles were lightweight, porous, and crumbled easily. They covered the belly, the tail, and the maneuvering engine pods protruding from the aft end of the vehicle. The tiles could not be applied as a single unit or even a few large pieces, because the orbiter’s airframe had to flex during launch and reentry as it encountered air resistance. So, the tile system ended up being a mosaic of thousands of tiles, each approximately six inches square and each with a unique shape. Each relatively fragile tile was glued to a felt pad, which was itself glued directly onto the aluminum skin of the orbiter. This allowed for slight movement in the orbiter’s structure without damaging the tiles. Every tile was numbered so that it could be readily identified and placed in the appropriate spot on the orbiter.

The tiles were not the only components of the orbiter’s heatshield. Some parts of the shuttle were exposed to more extreme heat than the tiles alone could withstand. The nose cap of the orbiter and the leading edge of its wings were made of a dark gray reinforced carbon-carbon (RCC) material that could withstand heat of up to 3,000°F. RCC was hard but brittle. Other parts of the shuttle, which were subject to much less heat during reentry, were covered with quilt-like blankets of silica and felt.

If the foam impact we saw had severely damaged the tiles on Columbia ’s belly or impacted the wing’s leading edge, searing hot plasma could enter the vehicle during reentry and melt the ship’s internal structure.