by Paul Dye
This history that you are about to read brings to life those days on console and in the meetings rooms, simulators, and training grounds where we lived for three decades. My goal is not to try and tell the entire story of the Space Shuttle program, but to give the reader a feel for what it was like to be inside the flight program—the months and years that went into preparing for missions, the weeks spent flying, and the aftermath, where we figured out what we had learned so that we could go back and do it all again. There are stories of remarkable technical insights and stories where no one really knew what was going on. Flying is deadly serious—but it is often wrapped in a smile, and there is much to laugh at. My stories are unique, as are the countless thousands that others can and will tell in their own books, their own memoirs. My reminiscences here don’t tell the complete story of the Shuttle flight program; they are the view of one person who was fortunate enough to have a wide view of it. So think of this as one perspective: a view behind the curtain of life in Mission Control, a life spent with dedicated individuals striving to do something unique, blasting people off the face of the planet and bringing them back after they had achieved an important goal.
It has been seven years since I last plugged my headset into a console in Mission Control, and some memories are beginning to fade, so it is time that I commit them to history so that others can learn what I was privileged to learn in all those years. I know that there are many space enthusiasts who would give just about anything to have been only a tiny part of a single Shuttle mission—and my colleagues and I were fortunate to be doing those entire missions over and over again for decades. Yes, privileged is the word—privileged to be trusted with such enormous resources to accomplish lofty missions. Privileged to be able to work with so many people who were so much brighter than I was. Privileged to have been at the pointy end of the exploration spear for so many years. It was hard, but it was worth it.
My stories include the trials and tribulations of what it is like to run a complex space mission. But while I hope that you learn something from all these tales, my real hope is that you appreciate the tremendous efforts put into raising humankind’s sights, from ground level to the stars, by the hundreds of thousands of men and women who served in the program through its many triumphs and its horrible tragedies.
The Shuttle program is over, and many of the details of how it worked are already lost. But future generations of technology will come along—they must come along—and our destiny to move off this planet will be achieved. I don’t know by whom and I don’t know when, but I trust that those future explorers will have their own stories, similar to those captured here. I hope my stories will entertain future generations with what it was like to push the path into the sky.
—Paul Dye
Dayton, Nevada
Prelude
The Last Time
No two shifts in the Mission Control Center (MCC) are ever alike. The facility is the same, of course—the big, gray, windowless building sits on the Johnson Space Center campus in Texas, along with office buildings and other large gray buildings that house labs, vacuum chambers, and engineering research facilities. Just a stone’s throw from Galveston Bay, this former cow pasture had been turned into America’s premier center for space exploration back when John F. Kennedy decided to send the nation’s heroes to the moon, and it has grown ever since.
Some days in Mission Control start slow and build. Other days, you come right out of the gate with a major problem, and you never slow down. And then there are the days when you simply don’t know where you’re headed: how quickly you’ll be on track or how quickly it will all go to worms. As I got out of my car in the Flight Director parking spot right next to the door (one of the perks of the center seat), I sniffed at the humidity and looked at the sky, wondering if the low clouds would break up for some afternoon flying later in the day. You just never knew on the Gulf Coast. At any rate, that was for later—now it was time to go to work. I passed through the double doors that kept the heat and humidity out of the carefully controlled climate of MCC and took the elevator to the second floor. I passed by the coffee pot without stopping—there’d be time for that later. I liked to focus myself on getting the shift started first. I passed the mementos and pictures of thirty years of Shuttle flight as I walked down the hall, then scanned my badge to open the door into the front room itself. A few flight controllers looked up and nodded a silent welcome as I headed for the Flight Director console in the center of the room.
I dropped my briefcase, pulled my headset out of its bag, and plugged it into the keyset jack under the console. The keysets were our link to the outside world—an intercom panel that allowed us to monitor and/or talk on any of thousands of various communications channels, called loops, that reached out around the world, and out into space. Each loop had a name and a purpose, and it was organized in a hierarchical structure that allowed specialists to have conversations among themselves while generalists could talk about the big picture. Generally, everyone involved in a mission was expected to monitor the air-to-ground communications channel—the talk between the crew in space and the CAPCOM (Capsule Communicator, the one person in the Control Center who did all the talking to the crew) on the ground—at all times. They were also expected to monitor the Flight loop, formally known as the Flight Director loop, which was the primary channel where everything was coordinated. The Flight Director was the owner of this loop, and it was how anyone needing to talk with Flight (the Flight Director’s call sign) provided information, asked questions—or pleaded their case.
Communications on any of the loops followed a protocol like that used by pilots and air traffic controllers for generations. If you need to talk with someone, you punched the Talk button on your keyset for that loop, and then spoke their call sign, followed by yours. “CAPCOM, Flight” would be how the Flight Director got the CAPCOM’s attention. The proper response would be “Flight, CAPCOM—go ahead.” This let the caller know that the receiver was listening. Conversation could then follow as required. Once that link had been established, conversation often became much less formal, with discussion, questions, answers, and brainstorming-type dialogue. This mix of formal calls and informal conversation often seemed strange to newcomers, but once they got used to it, the rhythm became obvious. You had to get comfortable with the fact that thousands of people in the program could be listening anywhere in the world to what you were saying, of course. But once you got over the fear of making a mistake (which everyone did now and again), communication came naturally—to most. There was a small percentage of folks who never got comfortable, and they simply didn’t make it as flight controllers.
Getting the rhythm of Control Center communications could take a little time, but once you did, you could listen to multiple conversations at once, and pop in and out of ongoing discussions with ease. Reading transcripts of a recorded keyset was often difficult, because you couldn’t recognize the voices the way you could when listening to an actual recording. Keyset audio was usually recorded in the Control Center, and flight controllers often asked for audio tapes of their sessions so they could go back and reconstruct what they had done right, and what they had done wrong. It was far easier to do this with audio than by reading a transcript.
There were two keysets on each console, one for the person who was currently responsible and one for the person coming on to relieve them—or simply for an observer who dropped in for a while. It was considered bad form to walk up and start talking to someone on console without being plugged in; you never knew what was going on in their other ear. They might be listening to multiple conversations all at once, and chatting with them face-to-face could break their concentration on something important. So, if you were just dropping in to see what was going on, you always wanted to plug in and select the same loops they had up on their keyset.
As I plugged in, sat down, and selected the loops I needed for my shift on this morning, I was pleased to find it generally quiet. Quiet is go
od in our business—everyone is working to a plan, and if everything is going well, there is little need for conversation. There was the usual hum of conversation among senior flight controllers in the Shuttle and Space Station primary control rooms and their support folks sprinkled in small rooms around the building. But the Flight loop was quiet, and the crew wasn’t talking much, indicating that they were busy working on the day’s scheduled activities.
All Space Transportation System (STS) missions had a number, with the final flight being number 135. The STS-135 crew was busy moving cargo between the Space Shuttle Orbiter Atlantis and the International Space Station (ISS) on this quiet morning. The hatches were open, and the two crews were busy working their nominal timelines when I got a call from our environmental and thermal flight controller, call sign EECOM, regarding a change in cabin pressure (dP/dT). EECOM sat one row ahead, and over to my right, against the wall, and when he called me, I looked over in his direction. The look on his face told me we had a problem. Before we were through, our world had changed—and the rest of the team had been drawn into the chase:
“Flight, EECOM—we’re seeing a negative dP/dT, and the crew has a master alarm. Recommend the joint emergency egress cue card in the Joint Ops. Page 331 in Joint Ops.”
I keyed my mic—“Copy EECOM. CAPCOM, let’s get them in Joint Ops.”
Joint Ops was the Joint Operations Checklist—a document that covered all the procedures that involved interaction between the Shuttle and ISS crews (and their respective control centers). The ISS used very little paper—most of their procedures were electronic. The Shuttle team, working with a vehicle whose computer systems were designed back in the 1970s, depended more on actual paper books. But for critical procedures—like a cabin leak—the necessary procedures were generally printed on cue cards—thick paper that could be slapped onto patches of Velcro on the walls and grabbed quickly when needed. Getting the crew in the Joint Ops procedure allowed everyone to know exactly what was happening, and what was going to happen next, regardless of whether they were looking at the procedure in paper form or on a computer screen.
“Atlantis, Houston… we see your cabin leak, and we want you on the emergency egress cue card in Joint Ops. That’s page 331 in Joint Ops, if you don’t have the card handy.” This was my CAPCOM getting the crew headed in the direction we wanted them—even though we knew they were probably already there.
I needed to make sure that the ISS was going down the same path we were, so I keyed my mic on my loop once again—“Station Flight, Shuttle Flight, my loop.”
The Space Station Flight Director was Courtenay McMillan, one of my colleagues from the Flight Director Office. Courtenay was one of those incredibly sharp engineers who grew up in the Space Station program, and she had a deep understanding of the systems as well as all the details of the international partnership. I was also certified as an ISS Flight Director and served in the position when needed—but I had nowhere near the depth of knowledge of the dedicated cadre of which Courtenay was a member. I was lucky to have her there, really running the show. While docked, the Orbiter systems and operations were mostly idling at a low level and the figurative (as well as the real) center of gravity was in ISS operations, led by ISS Flight.
For Shuttle missions to the ISS, I was always on the Shuttle side. But during routine orbit operations, Shuttle Flight Directors filled holes in the schedule to augment the folks who were dedicated to ISS, and (more importantly) to keep us up to speed on the Station and how its operations worked. The ISS Control Center was just out the door and down the hall from our Flight Control Room (FCR), in the “old” MCC building. It had been changed and refurbished, and was more modern than the “new” Control Center where we flew the Shuttle, but the operational concept was the same.
Technically—and officially—speaking, during joint Shuttle/ISS operations, the overall lead for the mission was the lead ISS Flight Director, and we worked under that person when the Shuttle was docked to the ISS. But realistically, we were equals, and masters of our own vehicles. Since we shared offices (in yet another building on the other side of the space center), staff meetings, and staffs, there were no mysteries in operating together—and we consulted regularly throughout the mission. In an emergency case like this, we needed to be in lockstep through the procedures and decision-making.
“Go ahead Shuttle Flight—we see the dP/dT.”
“Okay, we’ve got our crew on the cue card, and I expect everyone’s headed for their respective vehicles. Is your crew in Joint Ops?”
“Yup—we’ve got them on the card too.” Courtenay was fast, and I figured they were already with us—but a voice call made sure.
“Okay.”
“Flight, EECOM. T-Rez looks like about six hours, we’ll refine that.”
“Copy EECOM. Let’s see what happens when they get the hatch closed.”
Just like that, a quiet morning in MCC was interrupted by a large cabin leak in the joint stack—Atlantis and the International Space Station had been docked together for several days on this last of all Shuttle missions. The crew was busy transferring cargo in both directions, and suddenly, their atmosphere was going somewhere—but we didn’t know where—or why. The Joint Ops Checklist was used for malfunctions that could affect both the Station and Atlantis. Both crews had copies, as did all the Control Centers so that we could work together. T-Rez was a complicated number that was essentially a time that indicated how long you had to work the problem. The bigger the number, the better off you were; the smaller—the worse things looked.
Flight-controller software tools had changed a lot over the thirty years of the Shuttle program. In the first decade of the program, controllers had essentially what the folks flying Apollo had: software running in the Mission Operations Computer (MOC) down on the first floor. Equations for specific computations and calculations had to be written and coded months before a flight and inserted into the MOC’s software build for a particular mission. Displays were defined using a pencil and archaic worksheets, then were sent to the software division that coded them up. You could tell the MOC to perform a calculation with a dedicated button on your console. Changes were rarely possible after dedicated flight training had started for a mission and, oftentimes, flights were made with less-than-safety-critical software and displays not working right. Off-line calculations were often the quickest and best way for flight controllers to work, using calculators and small minicomputers to do computations specific to their discipline. Sometimes, worksheets were developed and documented in close-by handbooks for each discipline. It wasn’t until the mid-1980s that real computer workstations started appearing on various consoles to do the heavy lifting that simply couldn’t be done in the MOC—and flight controller creativity was unleashed.
The EECOMs of the latter days of the program had many software tools at their disposal. Computations for things like leak rates and T-Rez were done continuously and displayed on graphical plots, and rudimentary artificial intelligence algorithms backed up decision-making on potential future scenarios. Dumb green consoles of the Apollo days gave way to the blue consoles of the modern era, but the consoles themselves were simply fancy shells to house the workstation computers that ran the software that gave controllers more information and better options for every failure case.
“Houston, Atlantis. Just to let you know, we’re all headed to the Orbiter [Atlantis], and we can confirm we’re feeling the depress—I just had to clear my ears.”
Just like in an ascending airplane, the need to clear your ears was a sure sign of an atmospheric pressure change. The crew was letting us know that this wasn’t just a malfunctioning instrument—they knew that the pressure was actually dropping.
“Roger Atlantis. We copy that you can confirm the leak, and you’re headed to Shuttle.”
That was from CAPCOM, seated to my right. She knew she didn’t need to wait for my permission to answer a call like that.
My CAPCOM (Capsule Communicator), Shanno
n Lucid, was no stranger to spaceflight operations. Today, she was sitting on the ground on my right, as she had done so many times before. But this quiet, smiling grandmother was a veteran of over six months on the Mir space station—only the second American to live aboard Mir and, for decades, the holder of the spaceflight duration record for women. Shannon had served as my CAPCOM more times than I could count—many joked that we were like an old married couple, each of us knowing what the other was going to do in a situation. It was good to know that I could trust her to repeat exactly what the team needed as she carried out her job of being the only voice between the ground and the crew. Shannon had quietly disappeared from the Control Center a couple of years before, when she was assigned to be NASA’s Chief Scientist, stationed at headquarters in Washington, DC. Like me, she found that being a full-time professional resident of the inner Beltway was not to her taste. So, despite the promotion, she campaigned for a short stint in the job, and then a return to Houston and Shuttle operations. Shannon knew how to be cheerful on the outside, even when she might not have felt that way inside, and she rarely let folks see her without a broad smile. It helped the team to have her on console.
“EECOM, Flight. Any changes in the leak rate yet?”
“No Flight. It seems steady, but we’ve revised the T-Rez to eight hours now—we just have more data. We really can’t tell anything until they get the hatches closed.”
“Okay, all flight controllers, red on the Flight loop, please!”
Calling for a color was a time-honored tradition in the MCC—it was a way to make sure that everyone was listening, or that everyone had reached a certain milestone in a review, or that folks had given a “Go” on a particular request. In this case, I wanted to make sure that everyone was with me on the Flight Director voice loop, so I asked for a red. In the old days, each controller had a hardware panel with three buttons—red, amber, and green. The buttons lit a light in a matrix on the Flight Director console with the appropriate color. In the last half of the Shuttle years, the hardwired lights had been replaced by digital displays. They performed the same function as the hardwired lights, but they operated over the internet on the controller’s PC. It gave the same effect, but I always chuckled at how much programming it took to replace those simple buttons, lights, and wires. I had all reds in less than ten seconds—people were paying attention.