Riding Rockets

by Mike Mullane

  I snapped a few photos and then Velcroed the camera to the wall. This was another sacred moment in my life and I didn’t want to be distracted with setting an f-stop. I was looking into the cradle of my astronaut dream. There was no other place on the planet that held more memories for me. Two hundred and forty miles below were the deserts from which I had launched my rockets. Here was the Rocky Mountain West that had excited my imagination with its infinite horizons. Here was the sky I had navigated in a Cessna while making plans to be a test pilot and astronaut. Here was the place God had steered Donna and me together. And, now, I was speeding over all of it in a spaceship.

  Later we gathered around the window to watch the evening lights of Houston pass under us. The last rays of the setting sun were onAtlantis, so she would be visible as a bright star to anybody in the city who cared to look up. I wondered if someone had bothered to call our wives to tell them to watch for us. I would later learn that family escort Dave Leestma had. At the very moment I was staring downward, Donna was standing in an open field near our home and looking upward at our streaking star. After my return, she would tell me how the sight had overwhelmed her. “Mike, do you have any idea how amazing that was?You were in that point of light. I had to pinch myself to make certain I wasn’t dreaming.” I could appreciate her wonder. Every moment of orbit flight seemed like a dream to me, too.

  Swine Flight went to bed without a care in the world…or off the world, for that matter. The dangers of ascent were behind us. We had already scored our mission success. Our only problem was a slow leak inAtlantis ’s left inboard tire and that wasn’t a big deal. MCC had noted it in their data and had directed us to program the autopilot to keepAtlantis ’s belly pointed at the Sun. The heat was keeping the tire warm and its pressure up. We hoped the higher pressure would reseal the leak point. But, even if the tire went flat, we were scheduled to land on the Edwards AFB dry lakebed and would have its infinite runway to handle any type of steering problems after touchdown.

  I fell asleep secure in the machine that surrounded me. This would be the last time on the mission any of us would feel safe.

  Chapter 34

  “No reason to die all tensed up”

  The call from MCC was disturbing. During a review of launch video, engineers at KSC had seen something break off the nose of the right-side SRB and strikeAtlantis . The concern was whether the object had damaged our heat shield, a mosaic of thousands of silica tile, a design feature that earned the shuttle its nickname, “Glass Rocket.” The CAPCOM asked if anybody had seen any strikes during ascent or had noted any damage looking out the windows. “No” was our collective answer, but we did have a tool that would extend our vision to the shuttle’s belly—the camera at the tip of the robot arm. Within several hours MCC validated a heat-shield survey procedure in the Houston sims and teleprintered it to me. I was going to get some unplanned arm time.

  My heart was back in overdrive. Not only was I concerned about the possibility of heat-shield damage, I was also worried about the arm maneuver I was about to perform. It would put the RMS in very close proximity to the inboard portions ofAtlantis ’s right wing and fuselage, and I wouldn’t win any friends if I caused damage while determining there had been none to begin with.

  I swung the upper boom of the arm across the forward cargo bay and then tilted the lower boom over the right forward side ofAtlantis ’s nose. I swept the camera in a survey of that area, listening to Hoot’s cursing as I did so. The exterior cameras on the shuttle had long been a source of frustration with astronauts. They easily bloomed and washed out while imaging areas in full sunlight. The glare from the black heat tiles was particularly troublesome to the camera optics, and Hoot fought with the aperture controls trying to get a decent view. He was finally successful and our TV revealed a checkerboard of black tiles. It was exactly what a pristine heat shield should look like. But as I moved the arm lower the camera picked up streaks of white. There was no mistaking what they were. The surface of every belly tile was jet black in color. Any white would be an indication of damage, an indication that the surface had been ripped away by a kinetic impact. As I continued to drop the arm lower we could see that at least one tile had been completely blasted from the fuselage. The white streaking grew thicker and faded aft beyond the view of the camera. It appeared that hundreds of tiles had been damaged and the scars extended outboard toward the carbon-composite panels on the leading edge of the wing. Had one of those been penetrated? If so, we were dead men floating. Damaged black tiles might still protect the vehicle. Even a missing tile should be survivable. But a hole in the leading edge of the wing would positively be fatal and we had no way to survey the entire wing edge. The arm wasn’t long enough. (It was impact damage to a carbon panel on the left wing that would doomColumbia and her crew on February 1, 2003.)

  In the cockpit a shocked silence gave way to shocked exclamations. I called MCC. “Houston, we’re seeing a lot of damage. It looks as if one tile is completely missing.”

  The CAPCOM acknowledged my call. “We’ll get back to you.” MCC had our TV downlink so they were seeing what we were seeing, or so we assumed. I wondered if, at that very moment, there was a “Failure is not an option” speech being delivered as the flight director rallied the MCC team to deal with our situation. From our perspective it looked bad.

  After a few minutes the CAPCOM came back with the MCC’s analysis. “We’ve looked at the images and mechanical says it’s not a problem. The damage isn’t that severe.”

  Say what?!We couldn’t believe what we were hearing. MCC was blowing us off. There was no discussion of having ground telescopes take some photos ofAtlantis to possibly get a better view of the damage. There was no discussion of having us power-down the vehicle to give us the maximum orbit time to deal with the problem. There was no indication whatsoever that MCC thought we had a serious problem.

  Hoot was immediately on the microphone. “Houston, Mike is right. We’re seeing a lot of damage.”

  But after a short delay the CAPCOM came back with the original ho-hum assessment of “It’s not a problem.”

  We all looked at one another in disbelief. Are they blind? Did they think the white streaks were seagull shit? It was obvious to us that we had taken a very bad hit. Maybe the image that was arriving on the MCC monitors was of poorer quality than what we were seeing. I tried to sharpen the image but was no more successful than Hoot had been.

  Hoot tried again to convey the seriousness of what we were seeing and, again, MCC casually dismissed his concerns. We were in the Twilight Zone.Who is this speaking to us and what have you done with the real MCC? Maybe, I thought, MCC did know we had suffered major damage and were hiding that fact from us. There was precedence for that. On John Glenn’s Mercury mission the MCC had an instrument indication that his heat shield had come loose from his capsule, but they kept the information from him. Since there was absolutely nothing he could do about a loose heat shield, and, if it was loose, he was going to die, they reasoned there was no reason to tell him the truth. Without giving him an explanation, they had instructed Glenn not to jettison his retrorocket pack in hopes its retention would help keep a loose heat shield in place. It turned out there had been nothing wrong with the heat-shield attachment and Glenn was angry with MCC for withholding information from him. Could MCC be hiding a deadly situation from us? I couldn’t believe that. The MCC never gave up. If they suspected we had a serious problem, they would be pulling out every stop to get us home. It would beApollo 13 all over again. Their dismissive attitude must mean they believed we were okay. But I was going to be really suspicious if tomorrow’s wake-up music was “Nearer, My God, to Thee” and there was a teleprinter message saying we didn’t have to eat our broccoli.

  Hoot set the mic aside, obviously frustrated and angry. No matter what MCC was seeing on their TVs, he felt they weren’t seriously considering whatwe were seeing. At the moment I was glad our mission was classified. The public and press had not heard any of our
discussion. Unless one of the family escorts told the wives of our problem they would not know about it. I prayed that was the case. There was nothing they could do and they didn’t need the extra anxiety.

  I couldn’t sleep and floated upstairs to watch the sights. The autopilot was holding the shuttle’s belly to the Sun, courtesy of our tire leak, so I had to move from window to window to get the best view. I was annoyed at the inconvenience…until our unique attitude served up a space sight I had never seen before. I was looking through the overhead windows in a direction that was precisely “down”-Sun when the upward-pointing attitude control thrusters fired. As their effluent of billions of ice crystals blossomed above the orbiter, a perfect shadow ofAtlantis appeared and was carried into infinity at hundreds of miles per hour. The strikingly beautiful sight reminded me of Captain Kirk’sStarship Enterprise dashing into warp speed. I kept staring, hoping the display would repeat but it did not. The Sun dipped below the horizon andAtlantis was plunged into preternatural darkness. But there was one certainty about orbit flight: the passing of one incredible space sight only meant the arrival of another. My eyes were drawn to the lime green curtain of an aurora borealis waving over the Arctic Ocean far to the north. It brightened and dimmed as the rain of magnetic particles from the Sun varied in intensity. I was still staring at this phenomenon when the long streak of a shooting star brought my mind back to our heat-shield problem. In just a few hours that would beAtlantis …a shooting star blazing across the Pacific with a tail of ionized gas a thousand miles long. We were locked in an aluminum machine that would melt at 1,000 degrees. On reentry the belly tiles would be subjected to 2,000 degrees. The nose and leading edge of the wings would see even hotter temperatures. Just a couple inches of silica and carbon fiber were all that protected us from immolation, and our camera survey had shown some of those inches had been ripped away. The heat would definitely be getting closer to that aluminum. And what about the missing tile? Could the wind use the cavity it created to grab the edge of adjacent tiles and strip even more off, just like roof shingles being sequentially stripped in a hurricane? Engineers had always assured us that was not possible, but then I was certain the SRB nose cone engineers would have assured us their work could not fail either.

  Of one thing I was certain. IfAtlantis ’s wounds were mortal, our fortress cockpit would protect us long enough to watch death’s approach. Certainly it would last long enough for us to see multiple warning messages as various systems were affected by the heat. We would probably live to experience the out-of-control tumble and breakup of the vehicle. Even after our fortress was penetrated by the incandescent heat, death would not be immediate. Our pressure suits would protect us from the loss of cockpit air. Only when the fire penetrated the fabric of our LESes would we die. If we were lucky, unconsciousness would come before the heat began to consume our flesh.

  I kept returning to MCC’s assessment for comfort. It was hard not to yield to their conclusion that we were going to be fine. I had never been associated with any teams as good as those that manned the MCC. But ifChallenger had proven anything, it was that great teams do fail. A lot of very smart people had mishandled the O-ring issue that killed theChallenger crew. Were they now mishandling our heat-shield damage? Would anAtlantis presidential commission report end up containing the statement, “The crew radioed that the damage to their heat tiles looked serious, but in Houston their concerns were dismissed”?

  The anxiety was exhausting and I finally gave in to Hoot’s solution. The day before, as he floated to the windows to do some sightseeing, he said, “No reason to die all tensed up.” I would do my best to relax and enjoy the sights.

  Chapter 35

  Riding a Meteor

  “Fifty seconds.” Hoot gave the time remaining until the OMS deorbit burn. I floated behind Jerry Ross and watched the countdown on the computer displays. As the burn execute time neared, I tightened my grip on Jerry’s seat. The one-quarter G of the thrusting OMS engines was trivial but it was enough to put anything unrestrained on the back wall, me included.

  Astronauts have great faith in the OMS engines. They are the essence of simplicity. They have no spinning turbo-pumps to worry us, not even an igniter to fail and jeopardize our lives. The fuel and oxidizer are pushed into the combustion chamber by helium pressure, and their chemical composition causes them to ignite on contact. No spark needed. Getting stuck in orbit would ruin your whole day, so having a deorbit engine that was as foolproof as possible eased one of our perennial worries.

  At time-zero the cockpit shuddered under the hammer of the two engines. Small bits of food crumbs, which had escaped our cleanup, drifted to the back wall. Hoot and Guy watched the computer displays of helium pressures, temperatures, and other indications of engine performance. They were all nominal.

  The burn, and its acceleration on our bodies, ended. We were back in weightlessness. Hoot checked the residuals, which indicated the error of the maneuver. They were negligible. Whatever fate awaited us, we were now irrevocably committed. The OMS deorbit burn had clipped 200 miles per hour from our speed and changed our orbit so its low point was into the Earth’s atmosphere. There was no way we could climb back up to the temporary sanctuary of orbit.

  According to the checklist I should have been strapped into the mid-deck seat, but there was nothing to do or see down there, so I had asked Hoot if I could hang out on the flight deck and shoot some video of the early part of reentry. I would get into my seat before the Gs got too high.

  During the next twenty-five minutes we fell across the Indian Ocean, across the darkened continent of Australia, and shot into the night sky of the great Pacific basin. In our dive toward perigee,Atlantis gained back the velocity lost in the deorbit burn and added more. Shuttles achieved their peak speed on reentry, not ascent. The ride was as smooth and silent as oil on glass. The machine was on autopilot, with only her rear thruster jets active. Those were holdingAtlantis ’s nose 40 degrees high and presenting her wounded belly to the approaching atmosphere. Her aerodynamic control surfaces, the elevons on the wings and rudder on the tail, wouldn’t be able to hold her in attitude until we were much deeper into the atmosphere. If the rear thrusters failed, we would slowly drift out of attitude, tumble, and die. But an RCS system failure was far down on our lists of worries. The thruster jets were just smaller versions of the OMS engines, using a simple blow-down helium pressure feed system with propellants that burned on contact.

  Hoot called the descent. “Mach 25.1…340,000 feet…Guidance looks great.” We were slightly faster than 25 times the speed of sound and at an altitude of 64 miles. Our little green bug was tracking perfectly down the center energy line. We were on course for Edwards AFB, still 5,000 miles away.

  The atmosphere had thickened enough to become an obstacle to our hypersonic sled. Compression againstAtlantis ’s belly heated the air to a white-hot glow now visible from the front windows. I wondered what was happening underneath us. I had visions of molten aluminum being smeared backward like rain on a windshield. None of our instruments or computer displays showedAtlantis ’s skin temperature. Only Houston had that data. I wondered if they would call us if they saw it rising. I hoped not. Such a call would definitely have us all tensed up as we died. Even Hoot wouldn’t be able to laugh away that MCC call. I looked at our displays and meters, not sure which would be the first to reveal a heat-shield problem. They were all in the green. Hoot would later tell me his eyes were never long from the elevon position indicators, certain a left-right split in those instruments would be the first hint the right wing was melting.

  With the nominal displays I was happy to consider that our worries might have been misplaced. Maybe we had been alarmists. Maybe the damage was minor, as MCC had indicated. I still couldn’t believe that, but I prayed it was the case. I would have no problem offering the flight director, the CAPCOM, and everybody else an apology for having questioned their judgment.

  “Three hundred ten thousand feet…still holding M
ach 25…some Gs starting to build.”

  Hoot didn’t have to tell me about the Gs. Dressed in my LES I had added more than sixty pounds to my body. My zero-G-acclimated muscles were finding it difficult to bear that weight against even a small G-load.

  I looked upward through the top windows. As I had seen on STS-41D a snake of plasma flickered over us and slithered into the black. Periodically it would pulsate in incandescent-bright flashes that filled the cockpit like camera flashes. I wished I had paid more attention to the reentry light show during myDiscovery mission. Wasn’t this plasma ribbon brighter? Weren’t those flashes more frequent? Was itAtlantis ’s vaporized skin enhancing the show? There were no calls of distress from Hoot or Guy and the radios were mute. If the heat was dissolvingAtlantis ’s belly, the damage had yet to reach a system sensor.

  At 240,000 feet and Mach 24.9 the guidance system commandedAtlantis into a 75-degree right bank. She was high on energy and the autopilot was pulling her off course to increase the distance to landing. In that extra distance we would have more time to descend. We trusted the autopilot to turn us back toward the Edwards AFB runway at the appropriate time. It was impossible for a shuttle pilot to look out the window at a featureless ocean from 45 miles high while still 3,000 miles from the runway and manually modulate the orbiter’s energy state. We had to trust the wizardry of accelerometers inAtlantis ’s inertial measuring units to do that.