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CNN Live Today

Discussion with Former NASA Engineer Randy Avera

Aired February 03, 2003 - 11:10   ET

THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.

THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.


LEON HARRIS, CNN ANCHOR: We want to talk about the investigation. We want to keep in mind, that it is early in the investigation, and there are thousands and thousands of pieces of wreckage and sensitive data to analyze and recover. But NASA's findings so far suggest that damage from missing heat tiles may have been a critical factor in the shuttle disaster.
Randy Avera is a former NASA engineer who has worked on every single shuttle, as I understand it, and he also helped investigate the 1986 Challenger disaster. He's been lending his expertise to us here since Saturday's disaster, and we thank you for that, because we sure do appreciate it.

What we want to show folks right here is simply, first of all, I was amazed to find you had in your possession. This is an actual tile off of Columbia.

RANDY AVERA, FMR. NASA ENGINEER: Right, this was a tile that actually flew on STS-1, the maiden voyage of the Columbia, and the first ever launch of the space shuttle. This is what's called a scrap tile. It's got a red scrap print on it here. This tile was not acceptable to fly due to localized damage on it, and through the years, NASA has developed what they call standard repairs for tiles, kind of similar to going to a dentist to get a filling on a tooth filled, very small little superficial damage that can be repaired for further flight.

HARRIS: What I understand, though, is this -- you've told me earlier off camera, this represents state-of-the-art technology. However, this dates back to the late 60s.

AVERA: We landed on the moon with Apollo 11 July 1969. During that same time, the space shuttle concept was being in its -- was in its early phases of design, and just a couple years after that, some of the structural items were being machined, and ultimately, flew the first flight in April the 12th, 1981.

HARRIS: Now, as I understand it, this is just one of the many different kinds of tiles that are on a shuttle. There are five different types, and this is the black one they are using on the bottom of the shuttle, right?

AVERA: Well, when we say the word "tiles," there are really five different types of insulators. Tiles, there are two types of tiles, there are these black tiles, which are called HRSIs (ph). They are high-temperature tiles.

HARRIS: I'm sorry, Randy, can you hold that thought for a second.

AVERA: Sure.

(INTERRUPTED BY LIVE EVENT)

HARRIS: Right now, let's continue our discussion about these tiles. I'm sorry to interrupt you.

AVERA: Yes, we said that there are five different types of insulators on the orbiter part of the shuttle, and two of those are tiles. The black tiles are a high-temperature insulator, and there are white tiles that are lower-temperature insulators. What is in question this past weekend on Columbia are these black tiles, which are predominantly located on the belly of the orbiter, on the elebans (ph), which are on the trailing edge of the wings, and the body flap back behind the main engines.

HARRIS: To me, this feels more like a chalk-like material, and although this is some sort of hard coating that's sprayed on top of that. What is this?

AVERA: Yes, if you think about just a block similar to this of chalk or even a styrofoam ice chest from long ago before they started doing the plastic ones, very lightweight, low density.

HARRIS: It only weighs about maybe a pound?

AVERA: Not even a pound on this large tile, and the tiles vary in thickness, depending on the local temperature for these tiles, and also they have spaces between the tiles that accommodates the flexing of the structure. If there were two tiles that are flexing like this, if they knock heads, it could chip the edge, so the gap varies, and there are gap fillers that fill that gap, which is another part of the complexity of the system.

HARRIS: Now let me ask you about -- and again, this is very early in the investigation.

AVERA: Yes, absolutely.

HARRIS: But we've been talking off and on over the past couple of days now about what may have been some foam that may have come off of the external fuel tank, that may have hit one of these tiles. This feels fairly dense. How dense is that foam that covers the external tanks, and how could it actually, I guess, damage a tile like this?

AVERA: Well, the spray-on foam insulation, that orange-colored insulation on the large external tank, think of the external tank like a big thermos bottle, with temperatures inside from -283 degrees to - 400, very, very cold inside. That orange spray-on insulation is a completely different chemical mix that's applied differently, and NASA is also looking at the preparations that were done to the structure of that tank, and how that tank was -- this particular tank that Columbia flew with, how it was actually processed down in the New Orleans area, and are there any quality control issues there.

HARRIS: I read something this morning about it being the consistency of a brick. Is it harder than this material here?

AVERA: The density is definitely different. The tiles are extremely lightweight. If you recall back in the late 1979, 1980 timeframe, at Kennedy Space Center, the tiles were removed, about 28,000 tiles, and if you notice on the back this gray material -- it's a very hard.

HARRIS: It's a different color than the interior of it here.

AVERA: Right, that's what was added to the space shuttle tiles that were removed. The problem was back in 1979 and '80, that the glue that holds the tile on could not hold on to this very porous material. So the tiles were removed, this densification process was added, and the tiles were reattached.

HARRIS: And we should say the pictures we're watching right now are not of Columbia. This is Discovery, I understand, and as you can see here, that's the reassembly process with these tiles. This coating that's on here, we see now it matches the black tiles.

Now this coding that's on here, as we see now, that matches the black tiles there on the shuttle we just saw there on the video, this is actually, you say, a glass substance that's sprayed on here?

AVERA: Yes, it's a ceramic glass that is sprayed on. When the tile is manufactured, it's literally machined, and the white tile is then coated like just a spray-on coating, and then that coating is cured to a glass finish, but we're talking the thickness of the fingernail of one of your fingers.

HARRIS: And I noticed you were able to flake that off there pretty easily. You can see it comes off here.

AVERA: Yes, it's very easy to flip up some of the hard coating there, and realize that this is 1969 technology.

HARRIS: So what's in the pipeline now for next? I'm assuming that they're looking at new technologies to replace this.

AVERA: NASA has been looking for years with contractors into new technologies for making the existing system more durable and other alternatives. This has been going on for years with NASA. There's a lot of information on there. NASA needs the technical and the financial support to do these programs to -- not just for shuttle, but for all future re-entry vehicles, where high-speed reentries not only through our atmospheres, but other atmospheres of other planets would be important as well.

HARRIS: Randy Avera, thanks for bringing that in.

TO ORDER A VIDEO OF THIS TRANSCRIPT, PLEASE CALL 800-CNN-NEWS OR USE OUR SECURE ONLINE ORDER FORM LOCATED AT www.fdch.com







Aired February 3, 2003 - 11:10   ET
THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.
LEON HARRIS, CNN ANCHOR: We want to talk about the investigation. We want to keep in mind, that it is early in the investigation, and there are thousands and thousands of pieces of wreckage and sensitive data to analyze and recover. But NASA's findings so far suggest that damage from missing heat tiles may have been a critical factor in the shuttle disaster.
Randy Avera is a former NASA engineer who has worked on every single shuttle, as I understand it, and he also helped investigate the 1986 Challenger disaster. He's been lending his expertise to us here since Saturday's disaster, and we thank you for that, because we sure do appreciate it.

What we want to show folks right here is simply, first of all, I was amazed to find you had in your possession. This is an actual tile off of Columbia.

RANDY AVERA, FMR. NASA ENGINEER: Right, this was a tile that actually flew on STS-1, the maiden voyage of the Columbia, and the first ever launch of the space shuttle. This is what's called a scrap tile. It's got a red scrap print on it here. This tile was not acceptable to fly due to localized damage on it, and through the years, NASA has developed what they call standard repairs for tiles, kind of similar to going to a dentist to get a filling on a tooth filled, very small little superficial damage that can be repaired for further flight.

HARRIS: What I understand, though, is this -- you've told me earlier off camera, this represents state-of-the-art technology. However, this dates back to the late 60s.

AVERA: We landed on the moon with Apollo 11 July 1969. During that same time, the space shuttle concept was being in its -- was in its early phases of design, and just a couple years after that, some of the structural items were being machined, and ultimately, flew the first flight in April the 12th, 1981.

HARRIS: Now, as I understand it, this is just one of the many different kinds of tiles that are on a shuttle. There are five different types, and this is the black one they are using on the bottom of the shuttle, right?

AVERA: Well, when we say the word "tiles," there are really five different types of insulators. Tiles, there are two types of tiles, there are these black tiles, which are called HRSIs (ph). They are high-temperature tiles.

HARRIS: I'm sorry, Randy, can you hold that thought for a second.

AVERA: Sure.

(INTERRUPTED BY LIVE EVENT)

HARRIS: Right now, let's continue our discussion about these tiles. I'm sorry to interrupt you.

AVERA: Yes, we said that there are five different types of insulators on the orbiter part of the shuttle, and two of those are tiles. The black tiles are a high-temperature insulator, and there are white tiles that are lower-temperature insulators. What is in question this past weekend on Columbia are these black tiles, which are predominantly located on the belly of the orbiter, on the elebans (ph), which are on the trailing edge of the wings, and the body flap back behind the main engines.

HARRIS: To me, this feels more like a chalk-like material, and although this is some sort of hard coating that's sprayed on top of that. What is this?

AVERA: Yes, if you think about just a block similar to this of chalk or even a styrofoam ice chest from long ago before they started doing the plastic ones, very lightweight, low density.

HARRIS: It only weighs about maybe a pound?

AVERA: Not even a pound on this large tile, and the tiles vary in thickness, depending on the local temperature for these tiles, and also they have spaces between the tiles that accommodates the flexing of the structure. If there were two tiles that are flexing like this, if they knock heads, it could chip the edge, so the gap varies, and there are gap fillers that fill that gap, which is another part of the complexity of the system.

HARRIS: Now let me ask you about -- and again, this is very early in the investigation.

AVERA: Yes, absolutely.

HARRIS: But we've been talking off and on over the past couple of days now about what may have been some foam that may have come off of the external fuel tank, that may have hit one of these tiles. This feels fairly dense. How dense is that foam that covers the external tanks, and how could it actually, I guess, damage a tile like this?

AVERA: Well, the spray-on foam insulation, that orange-colored insulation on the large external tank, think of the external tank like a big thermos bottle, with temperatures inside from -283 degrees to - 400, very, very cold inside. That orange spray-on insulation is a completely different chemical mix that's applied differently, and NASA is also looking at the preparations that were done to the structure of that tank, and how that tank was -- this particular tank that Columbia flew with, how it was actually processed down in the New Orleans area, and are there any quality control issues there.

HARRIS: I read something this morning about it being the consistency of a brick. Is it harder than this material here?

AVERA: The density is definitely different. The tiles are extremely lightweight. If you recall back in the late 1979, 1980 timeframe, at Kennedy Space Center, the tiles were removed, about 28,000 tiles, and if you notice on the back this gray material -- it's a very hard.

HARRIS: It's a different color than the interior of it here.

AVERA: Right, that's what was added to the space shuttle tiles that were removed. The problem was back in 1979 and '80, that the glue that holds the tile on could not hold on to this very porous material. So the tiles were removed, this densification process was added, and the tiles were reattached.

HARRIS: And we should say the pictures we're watching right now are not of Columbia. This is Discovery, I understand, and as you can see here, that's the reassembly process with these tiles. This coating that's on here, we see now it matches the black tiles.

Now this coding that's on here, as we see now, that matches the black tiles there on the shuttle we just saw there on the video, this is actually, you say, a glass substance that's sprayed on here?

AVERA: Yes, it's a ceramic glass that is sprayed on. When the tile is manufactured, it's literally machined, and the white tile is then coated like just a spray-on coating, and then that coating is cured to a glass finish, but we're talking the thickness of the fingernail of one of your fingers.

HARRIS: And I noticed you were able to flake that off there pretty easily. You can see it comes off here.

AVERA: Yes, it's very easy to flip up some of the hard coating there, and realize that this is 1969 technology.

HARRIS: So what's in the pipeline now for next? I'm assuming that they're looking at new technologies to replace this.

AVERA: NASA has been looking for years with contractors into new technologies for making the existing system more durable and other alternatives. This has been going on for years with NASA. There's a lot of information on there. NASA needs the technical and the financial support to do these programs to -- not just for shuttle, but for all future re-entry vehicles, where high-speed reentries not only through our atmospheres, but other atmospheres of other planets would be important as well.

HARRIS: Randy Avera, thanks for bringing that in.

TO ORDER A VIDEO OF THIS TRANSCRIPT, PLEASE CALL 800-CNN-NEWS OR USE OUR SECURE ONLINE ORDER FORM LOCATED AT www.fdch.com