Was NASA Warned of a Danger to Shuttles 10 Years Ago?
CHUNG: What happened during the final minutes of space shuttle Columbia, before tragedy struck? NASA engineers are trying to reconstruct the last 32 seconds of communications that were transmitted from the space shuttle after Johnson Space Center computers lost contact. And as investigators gather Columbia's debris in Texas and Louisiana, they're also looking into reports of debris being found as far west as California. Joining me now from Houston with the latest on the investigation, CNN's space correspondent, Miles O'Brien. Miles, what are the headlines out of the briefing tonight?</s>MILES O'BRIEN, CNN SPACE CORRESPONDENT: The headline is, Connie, take the blinders off. This investigation has no preconceived notions about where it is headed, and basically, all that discussion about debris falling off that external tank as the root cause of the loss of Columbia, the shuttle program manager, Ron Dittemore, told us it just doesn't make sense to him. They've looked at it several different ways, relooked at the engineering analysis, and that foam, which he brought out a healthy dose of an example of, he says is just much too light, not dense enough to cause anything that would cause the loss of the vehicle and crew. So we asked a lot about whether there might have been ice, for example, on that piece of foam. They are ruling that out. They don't think that ice was there. They had a careful ice inspection. It wasn't a day where ice was forming on the tank in any unusual amounts. And so they think something else must have struck those tiles. Whether it happened on ascent, in orbit, or on descent all remains to be seen, Connie.</s>CHUNG: And they still aren't saying what that something else might be?</s>O'BRIEN: Hard to say right now. Could it be a micrometeoroid in orbit? The crew didn't report anything like that, and they were up 24 hours. If something struck that would be big enough to break away that many tiles, you'd think they would have heard something. They didn't radio down any clue of that. So it's really hard to say what might have happened. Maybe something on ascent that they didn't see with the cameras.</s>CHUNG: Now, I understand there was some shuttle debris found in California. Can you tell us about that?</s>O'BRIEN: Well, what's key about it, we think it's shuttle debris. It's according to NASA credible sources although they're still sending teams out there to verify all this. What's key about it is where it is found. If in fact there's any debris found in California, it will be very key because that was right at the beginning of the break-up of Columbia. and any pieces which fell off at that time will be right near the source of where the problem was. And there are a million parts on the shuttle, and just about every one of them, Connie, has a serial number on it. And if that number can be identified in the wreckage, investigators will be able to know almost precisely where it came from. The piece, which we don't know for sure if it is in fact linked to the shuttle, looks like it could be related to a so-called carrier panel, which holds tiles on in certain places. As soon as that investigative team gets there, we'll know for sure.</s>CHUNG: Apparently, there was a startling photograph that had some information, if indeed it's correct, that was taken by an amateur photographer in San Francisco. What can you tell us about that?</s>O'BRIEN: Well, it's hard to predict what that is. It could be just an artifact in the photography. That's one theory. But the investigators are saying it appears that there were some changes in the trail behind Columbia that indicate something happened. Now, was that change in the trail, was that a cause or an effect? Could the vehicle have struck something at that point? It doesn't seem very likely that it would at that altitude. It's not in space anymore. It's not like it would hit a piece space junk at 300,000 feet. But this amateur video clearly shows a change in that trail behind the orbiter. What that means is unclear right now, and what the investigative team will do is take a timeline and gather all these amateur images along with all the images they have, try to build themselves a fairly comprehensive movie, if you will, of those final minutes, and maybe be able to determine what that change was.</s>CHUNG: All right. Miles O'Brien, thank you. NASA was warned a decade ago in a report it commissioned that the space shuttle could be destroyed if tiles protecting important wing parts were damaged by debris during lift-off. But NASA engineers were never able to find a way to completely resolve the problem. Joining me now, one of the authors of that study, Carnegie Mellon professor Paul Fischbeck. Thank you, sir, for being with us.</s>PROF. PAUL FISCHBECK, CO-AUTHORED REPORT ON SPACE TITLES: My pleasure.</s>CHUNG: It was your report in 1990 that talked about these thermal tiles. And I'm wondering, did you actually worry that a shuttle could be lost?</s>FISCHBECK: We did a study to determine how risky the tiles were. The way we did the study was to look at which tiles were likely to be hit by debris coming off the external tanks. Also, which tiles got excessive heat or high heat on re-entry. And which tiles protected critical subsystems of the orbiter. If we found tiles that had all three of those things occurring at the same time, we deemed those tiles to be very critical.</s>CHUNG: Were those tiles that you thought were especially dangerous, or potentially dangerous, near the shuttle's wing wells?</s>FISCHBECK: Yes. There were a series of tiles that were located towards the center, near the wings -- near the wheel wells, that were -- that we deemed to be particularly critical.</s>CHUNG: So that would be critical to this investigation, wouldn't it?</s>FISCHBECK: Well, you know, our data was based on the first 30 to 40 flights. And things have changed since then. Nasa took some of our advice, and they corrected some of the problems that were occurring back then. But things have changed. They've changed the insulation on the external tank, and the tiles have become older. So there are other problems that may have crept in that we did not study.</s>CHUNG: Well, today we learned that the foam NASA is now saying may not have been the culprit after all. Does that square with your thinking?</s>FISCHBECK: When we did our study, we found that the probability of losing a tile was actually greater due to a poor glue bond than it was for debris knocking a tile off. So it still could be a tile- related problem but one that occurred, you know, outside of the debris problem itself.</s>CHUNG: All right. Sir, I want to play a little clip of the briefing from yesterday in which Major General Kostelnik, he's the deputy associate administrator for the space program, and he oversees safety issues. He was asked whether the tiles around the wheel areas were considered a particular safety issue. So let's listen to what he had to say.</s>MIKE KOSTELNIK, NASA DEPUTY ASSOCIATE ADMINISTRATOR: Not really that I'm aware of. I mean, that would be a good question to address to Mr. Dittemore tomorrow. He's been with the program a lot longer than I have. Actually, although I know there's a lot of issues with the tiles and so forth today, it's actually been a very robust system. It's actually worked very well in this process.</s>CHUNG: I think the kindest way to ask my question is to say did he not understand your report?</s>FISCHBECK: Well, I'm not sure he saw my report. I think that there are people at NASA that realize that some tiles are more critical than others and tiles that protect critical subsystems are the most important.</s>CHUNG: I guess the bottom line is do you feel that your 1990 report warned NASA of the potential problem and that they didn't do anything about it?</s>FISCHBECK: No. Quite the contrary. I think NASA took some very positive steps based on our report. Whether they did enough or they could have done more, that's something I cannot say. Any engineered system has associated risk. And there's no way to eliminate the risk completely.</s>CHUNG: So you don't think that you were raising the red flag and they ignored it. However, what you don't know is if they went the 100 miles?</s>FISCHBECK: That's unknown to me. That's correct.</s>CHUNG: Thank you so much, Paul Fischbeck, for being with us. And on to the twisted trial in Texas. We'll be right back.</s>ANNOUNCER: Next -- Clara Harris takes the stand in her own defense. And a shocker at the courthouse. What happened to Clara's lawyer? CONNIE CHUNG TONIGHT returns in a moment.