Joseph Senca, Mission Evaluation Room (MER) Tiger Team leader, was the first to address the group. His team, comprised of seven engineers from Boeing, United Space Alliance and NASA, had been formed through NASA protocol shortly after the first information about the debris strike became available. They were the same engineers who had been staffing the mission evaluation room, a support service for the shuttle program that provided engineering expertise for any mission in progress. As a team, they had studied all available imaging from Columbia’s launch, both stills and video. They had also used a computer modeling program called Crater to estimate the amount of expected damage. Crater had been designed in the 1960s to help Apollo engineers estimate the amount of impact damage, or “cratering,” that a spacecraft might encounter if struck by micrometeorites. In the early 1980s, the software was modified to be used with the Shuttle Program, mostly to project tile damage from falling ice and foam during launch.
Senca was NASA’s chief structural engineer, and he stood on visual cue from Pollard and walked over to the podium, where he could control his PowerPoint presentation. He woke his laptop computer from sleep, and the three ceiling-mounted LCD projectors and four ceiling-mounted 32-inch TVs came alive with the title slide of his presentation. The whirring fans from the LCD projectors provided the only sound—and movement—in the crowded conference room.
Mission Evaluation Room Tiger Team
STS-107 Debris Strike
Preliminary Findings
Senca pushed the button on the remote control and the next slide flashed onto the screen. Immediately, heads began shaking in disbelief.
Debris “Blob” Estimates
Estimated size: 20 X 16 X 6 inches, or 20 X 20 X 2 inches
Estimated blob speed: 800 fps or 546 mph
Estimated blob impact angle: < 20 degrees
Suspected source of debris: Left ET Bi-pod ramp foam
Conversations broke out all around him and Senca felt the control of his presentation slipping away. It was clear the room was divided among those who thought the numbers were high, alarmist-thinking even, and those who believed the numbers, but were shocked at the implications. Senca spoke over the noise, attempting to regain control. “I’d like to…” he paused, letting the engineers get some of their thoughts out. “I’d like to preface this slide and the presentation by saying that the tiger team has had only minimal time to prepare for this meeting. This presentation does not represent an exhaustive investigation into this debris-strike incident, but will hopefully be useful in bringing everyone up to speed on what we know as of this hour.”
As the group quieted, Senca continued. “The team examined all available hi-res video and film. And as most of you know, the available imaging was quite limited for this launch. The external tank separation as visualized and filmed by the crew offered no help, either.” Senca was referring to how during all Shuttle launches, a member of the crew uses a handheld camcorder, on this mission a Sony PD-100, to film the external tank separation as viewed through the orbiter’s flight deck windows.
“We weren’t able to appreciate the bi-pod area of the external tank from the edited 35 seconds of video footage the crew downloaded to us. We had the crew download the rest of the footage from ET sep [external tank separation], but it gave us no more information, because the ET section of the tank in question had already rotated out of view.
“Using the orbiter’s hatch [the external door where the crew enters the orbiter before a launch] as a reference, we estimated the blob dimensions as shown on this slide, roughly the size of a small suitcase. The foam insulation covering the left bi-pod area, while still attached to the external tank and traveling with the shuttle, was moving at 2,300 feet per second [1,568 mph]. At Launch-plus-81.7 seconds, with the shuttle at an altitude of 65,860 feet, a chunk of bi-pod foam broke free from the external tank. During the 0.161 seconds between when the foam left the external tank and when it struck the orbiter’s left wing, the debris blob, with its low ballistic coefficient, decelerated from 2,300 to about 1,500 feet per second [or 1,568 to about 1,022 mph].
“Essentially, Columbia then smashed into the slowing foam debris at 546 miles per hour.”
Senca had their attention now. He advanced to the next slide, which contained a short computer-animation movie showing how the debris left the external tank and fell toward Columbia’s left wing. “We used computational fluid dynamics modeling software,” Senca said, clicking the play button on the computer screen to start the animation, “to study the airflow around the external tank and orbiter, and to learn how that airflow would affect the falling debris. Our best estimates at this time show the debris striking the wing between RCC panels 6 through 9 along the leading edge of the left wing.”
Everyone in the room, even the youngest and least experienced NASA employees, knew the function of the RCC panels. There were 22 uniquely shaped panels that ran the length of each wing and served as a protective cap. Senca advanced to his next slide, showing the RCC panels for audience orientation.
NASA graphic, CAIB Report Vol. I, Page 55
Referred to widely as RCC panels, the Reinforced Carbon-Carbon panels were manufactured through a complicated multistep process using layers of laminated graphite-impregnated rayon fabric and impregnated resins. The final step of fabrication involved firing the panels in a furnace, like clay in a kiln, to 3,000 degrees Fahrenheit. The panels were a critical component of the orbiter’s thermal protection system, and could tolerate a temperature range from minus-250 to 3,000 degrees Fahrenheit. They were numbered beginning with “1” at the inboard aspect of the wing, closest to the fuselage, on up to “22” at the outside wing tip.
“The angle of incidence is very important here,” Senca continued, advancing to his next slide, which showed a cross section diagram of the wing’s leading edge. “If the debris hits at the underside of the curve, nearly parallel to the lower plane of the wing, then the damage is minimal. Our video review, however, and airflow modeling suggest that the debris hit the wing close to the center of the leading edge, thereby nearly doubling the force of impact.”
After Senca showed his last slide, which summarized the team’s findings, he fielded multiple questions and challenges about how the numbers and estimates were obtained. In response to those who thought the debris strike represented nothing more than a turnaround issue—something to be refurbished after landing, an expert in the orbiter’s thermal protection system assisted Senca by saying, “Don’t forget the design requirements of the RCC panel: They only have to withstand the kinetic energy of a 0.006 foot-pound impact. From the video analysis, it appears the debris strike may have well exceeded those design specifications.”
But no matter what questions were raised, no matter the perspective, the discussion always returned the same result.
“We could go on all day about this,” Senca said, “speculating this and that, arguing one method of modeling over another. But we keep coming back to the same point. There’s no way for us to know for sure what damage the wing has sustained, no way for us to tell for sure from the limited imaging we have. And that is why the tiger team is recommending we obtain outside imaging of Columbia on orbit immediately, using either satellite or ground-based resources.”
“Thank you, Joe, and your team as well, for your work on this,” Pollard said as she stood once again to redirect the meeting. “Outside imaging does sound plausible as indicated and based on your findings.” She looked to her left and right, polling the mission management team members. They nodded in agreement. “Okay, then, without any objection from the team,” Pollard continued, “following this meeting we will make the necessary contacts with Cheyenne Mountain to see about getting imaging of Columbia’s wing.
“There is something else I think we should be planning for,” Pollard said, “something we should keep in mind.” She looked down to her immediate left, to the Space Shuttle Program Manager, her boss and mentor, Reid Hamilton. He nodded, not sure what she had in mind,
but trusting her nonetheless. Pollard moved around her chair and walked over to the large whiteboard at the front of the room. With a red Dry Erase marker, she wrote in large all-caps, a single word, then circled it for emphasis.
A sudden hush fell about the room, except for those who were way in the back or out in the hallway, who couldn’t read what she had written.
“What does it say? What did she write?” voices demanded.
Chapter 9
Johnson Space Center, Houston
Mission Evaluation Room
Mission Management Team Meeting (unscheduled)
Saturday, Jan. 18, 2003
POLLARD ARGUABLY had a lot going for her. She had led a good mission so far, and had proved she was thinking ahead. But Brown had one thing she did not have, and that was decades of experience. And so when the moderator of NASA’s digital-reply service advised Brown what Pollard had written on the whiteboard, Brown realized he had heard enough.
As the noise from the mission management team meeting grew in response to what Pollard had written, the tiny speaker in Brown’s phone labored to keep up. From his office at the Kennedy Space Center, several states away, Brown had listened quietly to all that had been presented. He had been as patient as could be expected. But now it was his turn. He slid his feet off the desk, wincing at the back pain it produced, then leaned forward to get closer to the phone.
“Julie, I’d…,” Brown paused. He hated speakerphones and conference calls. He never remembered if he was supposed to pick up the handset or just talk loudly into that tiny hole at the base of the phone. How could there be a microphone in there?
He heard Pollard say his name, so he tried again. “Julie, I’d like to make a few comments before we end this meeting,” Brown said tentatively, wondering if anyone had heard what he said.
“Go ahead Ken, we can hear you,” Pollard said, smiling, realizing she sounded a bit patronizing. She felt no disdain for Brown; in fact, in the half-dozen times they had met, she had got on quite well with him. But Brown could be intimidating. He consistently demonstrated a gift for stripping a problem to its most critical elements, and if you were the one giving a presentation, there was a chance he would make you feel unqualified to be at the podium, feel somewhat smaller up there in front of some of the brightest minds in the universe. Easy now, get the job done through the people, Pollard reminded herself. Brown is simply a resource.
“Yeah, I’ve been listening to the meeting from here at Kennedy and there’s one thing I think we need to think about and discuss before we get outside imaging help.” Brown listened for a response, but heard nothing except a few coughs and muffled talking, so he continued. “For one thing, none of us really knows what the military’s capabilities are for imaging. It’s my understanding that no one in the operational team there for STS-107 has that level of security clearance.”
“Ah, that is true, Ken,” Pollard said, wondering where he was going with this.
“We’ve all seen satellite photos of Earth from space and pictures of orbiters docked at the space station. From an imaging standpoint, those are relatively simple images to get. But to get a quality picture of Columbia’s wing on orbit, one that can really help us quantify the damage, if there is any, seems like a time-intensive task. My concern is the amount of time it will take to get such an image, having to first tell the crew what’s up, coordinate with Cheyenne Mountain for necessary vector changes on Columbia, and then wait for an imaging window to open. What I mean is, we don’t want to waste any time here.”
“What are you suggesting we do instead, Ken?” Pollard asked as she paced back and forth behind the management team with a puzzled expression—her chief image guy was suggesting imaging was not the way to go. This can’t be happening, she thought.
“Well, I say we tell the crew about the debris strike and then fast-track the procedure development to get them out there on the wing so they can physically inspect the damage.”
Brown’s voice rang throughout the conference room in a scratchy, distorted telephone voice, but what he had said hung like a sledgehammer at the end of its backswing.
“If we get imaging,” Brown insisted, “we’ll likely still want to quantify the damage anyway, which means we do a spacewalk. I’m telling you, when the crew finds out about the debris strike, they’ll all be at Columbia’s aft flight-deck windows, craning to see the wing. And when they realize the open payload-bay doors block the view of RCC panels 1 through 11, they’re gonna want to go out there. They’re gonna want to see for themselves whether their spacecraft is damaged.”
Chapter 10
Johnson Space Center, Houston
Mission Control Center
Saturday, Jan. 18, 2003
“HELLO,” ALLAN WARNER SAID after pushing the flashing intercom button on his phone.
“I have a call for you, Mr. Warner. It’s coming through the JSC Message Center, line two. He did not offer his name, but said only that he’s calling from the Cheyenne Mountain Space Defense Operations Center. Do you want…”
“No, no, I’ll take it, thank you.” Warner had been reviewing the recommendations from the Mission Management Team meeting. He pushed the button for line two and identified himself.
“Mr. Warner, yes, Commander Scheckter here.”
As the Flight Dynamics Officer (FDO, pronounced “Fido”), Warner was responsible for overseeing the general flight path of Columbia and her payloads. The FDO was also NASA’s designated position for all verbal communications with SPACECOM, including “threat and warning” messages for orbiters in space. If an orbiter was in a position to run into space junk, Warner was the person Space Control would contact. Warner was also the only one authorized to request on-orbit imaging of Columbia if necessary. His security clearance allowed him access to at least some of the military’s secret imaging capabilities.
But the bulk of communication between the Johnson Space Center and SPACECOM, such as daily updates on Columbia’s current vector or any planned major changes in trajectory, occurred through messages entered into the JSC Message Center. Warner was familiar with Commander Scheckter’s brevity of speech, his military-style economy of words, and preference for written electronic communication versus verbal conversation over the telephone. And so, whenever Scheckter used the phone, Warner feared something was wrong.
“I’m glad you called, actually,” Warner said, straightening his posture. “I was just about to call you—to inquire about getting imaging of Columbia on-orbit.” Warner realized he was talking too fast and sounding nervous. Truth was, Scheckter, and everything about Cheyenne Mountain, freaked him out. The place flat out scared the crap out of him.
Warner had taken a VIP tour of the facility two years earlier as part of his FDO training program at NASA. During his visit, Warner had all his suspicions about how he was not fit for military service solidly confirmed. The personnel he met were all cordial, respectful and professional to him, of course; their actions in fact made him feel proud, even patriotic. It was the setting—with its cold, hard, carved form, and which required myriad systems in place just to keep it alive—that unsettled him. Buildings perched on massive springs, blast valves were installed into the air-intake and fresh-water supply lines, and six 2,800-horsepower diesel generators powered it all. To Warner, Cheyenne Mountain was a soulless beast of a place.
“Who works every day beneath 2,000 feet of granite for God’s sake?” Warner had asked his assigned MP escort.
The MP replied simply, “About 1,500, sir.”
“Well, why don’t you start with what you have, and then I can ask my questions about imaging,” Warner said, feeling like he was regaining his composure.
“Okay, that’s fine,” Scheckter said. “Earlier this morning, while processing yesterday’s space surveillance network data, one of our Space Control specialists noted a small object floating adjacent to Columbia’s left wing. The data shows it appearing initially at 3:57 P.M. yesterday, ah, which would be—correct me if I’m wr
ong—Columbia flight day three.”
“You what? You found what?” Warner demanded. “An object entered the box and you’re just calling me now?”
With cool precision Scheckter responded, “I never said it entered the box. I said it appeared next to the wing. Prior to 3:57 P.M. it did not exist. Actually, we were wondering if maybe you lost something out of the payload bay, perhaps a tool, a panel, or a part of something…”
Warner’s mind was spooling up, gaining speed, searching for clarity. His ears were still taking in what was being said; he was listening, barely, his brain busy with other tasks. “No, nothing came out of the payload bay, no reports of anything from the crew—I mean they haven’t been out there—no space walks. I mean, it’s possible something could have come loose at launch but…” Warner was working his algorithms. “Tell me again, how big does an object have to be for space surveillance to see it?”
“Greater than ten centimeters across,” Scheckter replied flatly.
“Ten centimeters,” Warner repeated, stretching out his middle finger away from his thumb, picturing the size. And then it came rolling in. The size of the reported object, the proximity to the wing, photo engineers concerned about a left-wing debris strike, and the object just appearing next to the wing.
Warner felt the clarity of his thoughts growing; they were a churning storm poised to make landfall. “Oh God,” he mouthed. He was suddenly unable to make a sound.
“Didn’t you say you had some questions about imaging?” Scheckter asked, hoping to fill the silence.
And that question was the final missing piece for Warner. The imaging, he thought—the need to get satellite imaging of Columbia. The debris strike. The Mission Management Team meeting. Engineers scratching their heads—should we get satellite imaging or do a space walk?
Brown was right! Forget the imaging; get ’em out on the wing!
Launch on Need Page 5