NASA Podcasts

NASA 360 - Season 1, Show 9
04.21.09
 
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IN THIS EPISODE (in order of appearance):

PLUS:




[upbeat electronic music]

Jennifer: Hey, I'm Jennifer Pulley. Welcome to NASA 360. Okay, right off the top, I got a quick question for you. Where does NASA launch most of its space missions? Well, for those of you that don't know, let me give you a hint. If I said, "Launch at the Cape," would you know it then? Yep, it's Cape Canaveral, the Kennedy Space Center.

Jennifer: The Kennedy Space Center has been the launching point for virtually every NASA mission since, well, the beginning of NASA. This place is amazing, and today you're in for a special treat, because NASA 360 is going behind the scenes to take a closer look at some of the amazing facilities here at Kennedy, and we'll also meet some of the people down here on the space coast of Florida who make those launches possible.

Jennifer: Here's Johnny Alonso to get the show rolling.

Johnny:Hey, how's it going? I'm Johnny Alonso. Today I'm at one of the most recognizable places in the world, the Kennedy Space Center in Florida. This is where all of the most important American missions have been launched.

Johnny: Dig it: missions like Mercury, Gemini, Apollo, Skylab, and all the shuttle flights, and not to mention hundreds of other important scientific flights too. This will also be the place where NASA's new Ares rocket will blast off into space when we go back to the moon.

Johnny: So this is the place to be if you want to know how NASA gets these huge rockets into space.

Launch Controller: >> Main engine ignition.

Launch Controller: Three, two, one. >>

Johnny: So what does it take to get a vehicle in space? Well, it's not very easy. Thousands of people must perform extraordinary jobs everyday just to get a vehicle ready for launch. And I'm not talking about all the planning and engineering it takes to build a spacecraft, no, I'm just talking about just getting it ready to fly, putting it in launch position and blasting off into space.

Johnny: But before we start our tour, lets take a few minutes to talk about some of the important historical events that have happened here at Kennedy. It wasn't until near the end of World War II when the U.S. really started getting interested in rocket flight.

Johnny: The main reason was because the Germans were using a rocket called the V-2 as a weapon against us. Even though this was a terrible weapon, American planners saw the potential this rocket could have militarily and as a forerunner to large rockets that could help us explore space. So after the war, the military brought about 100 captured V-2 rockets back to the states and began testing them in New Mexico. It wasn't long before researchers realized that they needed a place to test longer-range rockets. So in 1949, president Harry Truman established the joint long range proving ground at Cape Canaveral. The Cape was the perfect place for this type of testing because its location was so remote that nearby communities would not be in danger, and, of course, the weather permitted year-round testing.

Johnny: Okay, fast-forward a few years. It's now 1957, and the Navy was testing the Vanguard rocket to send the first satellite in space. They had sent up two of these rockets on suborbital test flights but were all in for a big shock on October 4, 1957, when the Russians beat us to the punch, launching Sputnik, the first man-made satellite, into space. The race for space was now on, and soon the name Cape Canaveral would be one of the most well-known places on earth.

Johnny: Soon after Sputnik was launched, NASA selected the first astronauts to participate in our manned space flight efforts: and one of the main goals was to learn as much as possible about space to help us to get ready to go for the moon. On May 5, 1961, Alan Shepard became the first American in space with the launch of the first Mercury flight, called Freedom 7. Although his flight was suborbital and only took about 15 minutes, the U.S. had done it. We had put an American into space for the first time. And that same year, president Kennedy told the world that the us would be striving to put humans on the moon and bring them back safely by the end of the 1960s. So with this new deadline, training and flights began getting fast and furious.

Johnny: After the Mercury missions were complete, project Gemini was launched. Astronauts gained valuable information on docking in space while also performing the first American spacewalk. But with the last Gemini flight in 1966, all eyes turned to Apollo, and the moon was our next target.

Johnny: It's amazing, isn't it? In just under 10 years, we went from barely understanding how to get humans off this earth to preparing to send them to the moon. So on July 20, 1969, the nation's goal of putting humans on the moon was realized when Neil Armstrong and Buzz Aldrin landed at the Sea of Tranquility on the moon. This flight was followed with six other Apollo flights, with Apollo 17 becoming the last flight to the moon. NASA quickly closed the book on the moon missions, focusing their talents and technology on a new craft called the space shuttle.

Johnny: Now, many of you watching this have never know a time when humans weren't flying in space. A lot of us take that for granted. But let me tell you something. It's not easy to prepare everything you got to do to get up into space.

Johnny: All right, so are you ready to go on the tour? Let's roll and check out some of the facilities here at Kennedy and meet some of the hardworking people that are making these spacecraft fly.

[heavy rock music]

Johnny: The V.A.B. is where the space shuttle gets assembled for space flight. This is how it works. First the solid rocket boosters are mated together and attached to the giant external fuel tank. Then the orbiter gets towed and raised to a vertical position with overhead cranes. It's attached to the other components and is ready to go. Well, almost ready to go.

Johnny: So how do they get the orbiter out of this building and onto the launch pad? Well, with one of the baddest moving trucks you've ever seen. Around here, they just call it the crawler.

Johnny: Tell me about the crawler.

Myers: Well, Johnny, the crawler was built about 1965, and it was basically the-- it was the main transport to take the Apollo vehicle from the vehicle assembly building out to the pad.

Johnny: This thing is huge.

Myers: It's 130 feet long, and about 115 feet wide (39.6 m long, 35 m wide).

Johnny: And what's the max weight on this thing?

Myers: Well, let's see, the crawler-- it's about 6-1/2 million pounds (2,948,350 kg). Pretty heavy. So it stays on the ground, no problem, you know? [laughter] but the crawler carries-- right now, it's carrying about 13 million pounds (5,896,700 kg).

Johnny: 13 million pounds (5,896,700 kg).

Myers: Yeah, so you got a total weight of crawler and vehicle of about 18 million-some pounds (8,164,662 kg).

Johnny: Oh, my goodness.

Myers: Rolling down the road.

Johnny: I'm going to assume this thing doesn't go very fast.

Myers: It's not real superfast. We like to keep it probably around a mile an hour (1.6 kph). Now, it's designed speed when it was first designed was almost a speed of two (3.2 kph). But actually, it is fast when you're on the crawler, I mean, because of the mass that it's moving.

Johnny: So you fill a tank up--

Johnny: [laughs] No, I'm just ask you, if you fill up the tank, I mean, you know, what can you get per gallon?

Myers: Well, it's about 38 feet per gallon (3.06 meters / liter).

Johnny: 38 feet per gallon (3.06 meters / liter)?

Myers: Oh, yeah. Yeah, and we actually have two tanks on the crawler. Each are 2,500 gallons (9,463.5 L) apiece.

Johnny: Oh, my goodness.

Myers: Yeah, so it'll last a couple of operations.

Johnny: Tell me, what does the crawler do?

Myers: Well, the crawler-- the basic task of the crawler is to pick up the mobile launch platform. The mobile launch platform, of course, has the vehicle stack on it. And it moves it from the assembly building, and it moves it out to the pad and then sets it down and then moves back away from it. And then once the vehicle launches, it goes and picks up that mobile launch platform and brings it back to the vehicle assembly building for another stack.

Johnny: Is there only one crawler?

Myers: Uh, no, there's actually two.

Johnny: Are there?

Myers: Yeah, NASA had two of them built back for the Apollo program.

Johnny: All right, so we know what kind of mileage this huge thing gets. How's it powered?

Myers: Well, you know, funny you should ask that. Why don't we just go up here, and we'll check it out?

Johnny: Let's go.

Myers: Yeah, walk back into history.

Johnny: Wow, look at this.

Myers: These engines here, those are the same engines that have been on here since '65.

Johnny: Since 1965.

Myers: This is what powers the crawler here. There's actually two of these. There's one here, one on the other side. And each one of these powers two 1,000-kilowatt DC generators.

Johnny: Really?

Myers: Kind of works like a diesel-electric locomotive.

Johnny: Sure. Let me ask you, so how do you move this thing? How do you drive it?

Myers: Well, come on. I'll show you.

Johnny: Sure.

Myers: We'll walk right out here.

Myers: Okay, Johnny, come on. Let's come in this cab right here.

Johnny: Okay. Oh, cool.

Myers: This is the operator's cab.

Johnny: Wait a minute. That's the steering wheel?

Myers: Yeah, it's not your typical steering wheel. [laughter]

Johnny: For such a big rig, my god.

Myers: For probably one of the largest vehicles, this is quite a small steering wheel. The steering itself is-- of course, it's all electronic.

Johnny: Yes.

Myers: And what's happening with this wheel is, when you're turning it, it's sending a signal back to what we call our PLC, which is programmable logic controller, and it takes that signal, sends another one out to some hydraulic pumps that in turn move these large cylinders out here. And the cylinders themselves move the trucks back and forth, and, of course, it steers itself down the crawler way, as to, depending on what kind of degree you put in.

Johnny: Is that how you control the speed?

Myers: Exactly. This is just like-- this is like a foot pedal, you know, speed pedal in the car? What you're doing here is, you just increase the-- increase this pot control, and it takes those-- when we looked at those generators back there, it excites those fields.

Johnny: Yes.

Myers: And by exciting those fields, we can adjust the speed of these propel motors down there. And then along with a gas pedal, you know, you got a transmission. It's just like a car: forward, neutral, reverse. The other thing that the crawler operators are always worried about is this height, 'cause the one of the basic operations of the crawler is moving the mobile launch platform out to a set of columns, setting those down, and moving out from under it. So he's always aware of what his height is, and he does it here by this average height meter.

Johnny: It's been a pleasure. It's a lot of fun. Thank you so much for bringing us around today.

Myers: Oh, no, we enjoyed it, Johnny. We're glad to have people come out and take a look at our machine.

Johnny: Definitely. This was a lot of fun. You're watching NASA 360. We'll be right back.

[heavy rock music]

Jennifer: Wow. That crawler? It's huge. To give you a better idea of just how big that thing really is, listen to this. Those tracks that they use, each have 57 shoes, and those shoes weigh nearly 2,000 pounds (907 kg) each. All right, let's switch gears a little. You may have heard of something called the thermal protection system on the shuttle, you know, those black tiles along bottom? You may also know that they help shield the craft from the 3,000-degree (1,649 C) reentry heat when it comes back into the earth's atmosphere, but do you know what they're made of? Well, it's a pretty cool story. Johnny is over at the thermal protection system facility to see how the process works.

Johnny: Okay, so we're here at the thermal protection system facilities with Martin Wilson. How are you?

Wilson: I'm doing great.

Johnny: Good to see you.

Wilson: John, you too.

Johnny: And this is where tiles begin life, right?

Wilson: This is the part of the process where tiles begin. You know, this object right here is called a tile production unit.

Johnny: Okay.

Wilson: Weighs about three pounds (1.36 kg). It's very low density material, rigidized fiber ceramic, capable of withstanding around about 2,300, 2,400 degrees, over 3,000 (1,260 C; 1,316 C; 1,649 C) for very short periods of time. And we make these billets, as we call them in here. We start off with several different types of ceramic fiber that are all pre-kitted and pre-weighed. These materials are put into this blender that we have over here with about 25 gallons (94.6 L) of water and various chemical additives-- ammonium hydroxide, silicon carbide, other surfactants, and some what have you. We put them in this machine, basically turn it on, and it blends the fiber for around about 12 minutes.

Johnny: Okay.

Wilson: And after the blending process is done, we go ahead and we put it in this casting tower over on the other side of the room. This device here is called a casting tower, and it's really, simply a hydraulic press. We have around about 25 gallons (94.6 L) of the prepared slurry, which is the chopped fiber, water, surfactant, and the other additives. And we now go through the process of loading it into the press. And despite many years of high-tech methods of getting the slurry from the bucket into the tower, this is how we do it. It actually takes about 25 gallons (94.6 L) of water to produce one block. And actually, for the C.E.V. for the Orion, we're using this. That's actually what this is for, because these tiles are very light, extremely resistant to micrometeorites. And because of the trajectory of the new vehicle, it's gonna see some pretty high temperatures, but for fairly short periods of time. And now they start this gradual de-watering process, which actually takes a little while to do. This stage of the process, the billet's been pressed. The next step is to actually extrude the billet out of the tower. At that point, it'll be taken to the other end of the building, dried for 16 hours at 250 degrees (121 C), and then ultimately fired in a kiln at 2,450 (1,343 C) for several hours, and that will give you the block that I showed you to start off with.

Johnny: So we are in a new section of the building. Why don't you tell us where we are, and what do you do here?

Wilson: Well, this is the machine shop, and this where the actual base tiles are machined out of the billets and material that we produce down at the other end of the building. There's several different ways we can do that. But primarily, all of the tiles are machined using diamond-coated tool steel cutters, either on a manual machine, which is called a tracer mill. The majority of the tiles we actually produce on these machines back here. This is a five-axis, numerically controlled mill. They use these type of tools: these are diamond tool steel cutters. This machine is highly automated. The program originates back in the numerical design area. The whole--the entire process takes about 20 minutes. In the beginning, we'll start off taking a series of rough cuts, just to take the bulk of the material away, and then there's a series of smaller and finer tools that'll come in and start to take those surfaces away.

Johnny: So once they come out of the machine shop...

Wilson: Yes, the next step of the process is to actually apply a series of ceramic coatings. The materials themselves at this point do not have a lot of strength, so we put a coating on. It's either a black or white coating, depending on the emittance properties required of the tile, and it's put on in several layers. We make the coatings in here. They're basically very finely divided ceramic powders, either in alcohol or water, with various thickening agents, and emittants and pigments. They're all sprayed by hand. The coating goes on in basically a three-step process. But again, it's one of those processes that is very exacting. A lot of weights and measures to make sure the coatings are the exact correct thickness. This is the step that follows the application of the coating.

Johnny: Okay.

Wilson: That we just saw. The coating's been applied and dried for several hours, just at room temperature.

Johnny: Sure.

Wilson: But for the coating to consolidate or sinter, it has to be heated at 2,200 degrees (1,204 C) for 90 minutes. That's what we do in these kilns. And we have a tile in here that's been undergoing that sintering process. You can go ahead and take it out. The tile's at 2,200 degrees (1,204 C). And you'll be able to see how the black coating starts to cool down very, very rapidly. Now this is just raw, uncoated material.

Johnny: Sure. Look at them. They're glowing inside.

Wilson: But those, you can actually go ahead and--

Johnny: These you can pick-- you pick up?

Wilson: Yeah.

Johnny: These.

Wilson: Yeah, you just go ahead and grab them.

Johnny: Are you kidding me? Am i doing it right?

Wilson: Yep. Just pick them up by the corners.

Johnny: I'm so afraid to-- what's that? I'm afraid to.

Wilson: As long as you just handle them only with lightest of pressure.

Johnny: With the lightest of pressure.

Wilson: You can go ahead and pick them up.

Johnny: This is so cool. [laughs] that's 2,000 degrees (1,093 C)?

Wilson: Yep, it's 2,000 degrees (1,093 C). It's cooled off fairly quickly on the corners. You know, and that's the reason you're able to pick it up. It's still 2,200 degrees (1,204 C) in the middle, you know, it will burn you if you're not too careful with it.

Johnny: Of course.

Wilson: But it is silica. It's very low density and has a relatively low heat capacity, which is the only reason you're actually able to do that.

Johnny: So tell me, how does the shuttle tile work?

Wilson: Well, in its simplest terms, a tile like this one here, it is really just a very, very lightweight superinsulator. And you can put heat to one side of it, and eventually, the back side of the tile will get hot, but for any type of reentry vehicle, you know exactly what reentry consists of, so you know approximately what the heat loads are gonna be, so then it's just a question of designing the tile to be of the correct thickness. And I can actually take this tile and heat it up with a blowtorch, and you can see quite rapidly, the surface will get up to about a little over 2,000 degrees (1,093 C) with just this propane torch.

Johnny: Okay.

Wilson: But the actual heat is soaking through the tile very, very slowly. I mean, I could stand here for probably around about 20 minutes before the back of the tile becomes uncomfortable hot and I'd have to put it down.

Johnny: Really? It's not hot now on the other side?

Wilson: No, it's not hot at all. I've got my finger right on the back side of it, and I can't feel anything. It's probably going to take about seven to-- seven or eight minutes before it starts to warm up, so, yes, you can put your finger on the back of it.

Johnny: Wow. Yeah.

Wilson: It's just nothing.

Wilson: And basically, that's how most of these ceramic insulating strategies work. Just very, very lightweight. They delay that heat pulse, and, you know, can be used for any reentry vehicle, be it an earth reentry vehicle or a one entering Mars or any other planet.

Jennifer: So when you think of space flight, one thing you might not immediately think of is parachutes. But let me tell you, chutes really are important. I mean they return the solid rocket boosters back to earth, they help slow down the space shuttle on landing, and they will be used again when we phase out the space shuttle and begin flying our next-generation space vehicles. Johnny jetted over to the parachute facility to find out more.

Johnny: Okay, so we are here at the parachute refurbishment facility with my buddy Terry, Terry McGugin. How's it going, bro?

McGugin: Good, Johnny.

Johnny: Good to see you.

McGugin: Glad you could stop by.

Johnny: Thank you. Tell me, what are we doing here?

McGugin: Okay, what we're doing here is, this place manufactures, refurbishes, repairs, and packs the parachutes for the solid rocket booster first stage vehicle for the shuttle program.

Johnny: Why isn't the chute solid? Why is it like this?

McGugin: Okay, when you see the parachutes fly, they appear solid.

Johnny: Yes.

McGugin: Ribbon parachute like this withstands the heavy loads and the high-dynamic loads much better than a solid parachute would. If you try to put a solid parachute out with this much drag at the speeds that we're going out, you'd probably tear the parachute up. The boosters themselves, the white structures that are on the side of the shuttle system, they come back and are reused time and time again. They're certified for up to 30 flights, so, you know, we're still using the boosters every time again. So we don't build a new booster every time, we integrate the pieces into a new booster every time.

Johnny: So what are these parachutes made of?

McGugin: The major component--in fact, almost the only component of the SRB parachutes is nylon. The ribbons are fairly strong, but not that strong. These are good for about 1,000-pound (454 kg) tensile strength, if you were to tear it in this direction. A little bit more strength here, because the load on the parachute is carried by this part, and this just creates drag and holds the structure together.

Johnny: How big of a space can this incredibly long parachute--

McGugin: This is a big parachute. And this parachute's 136 foot (41.4 m) across at the bottom when it's full inflated.

Johnny: Right.

McGugin: And we pack it into a bag, and the whole packed parachute weighs about 2,000 pounds (907 kg), 2,200 (998 kg) and change.

Johnny: Wow. Oh, check it out. We got a couple guys working on one right now.

McGugin: Sure. What we got, we got Tom Gilliam and James Murrow that are working on the parachute, getting it put in the deployment bag here. And as you see -- what we got -- the deployment bag is inverted, and they're stuffing the parachute in vent first into the bag.

Johnny: Okay.

McGugin: They fold the parachute very carefully, and then lay it into the parachute deployment bag very carefully, and they tie it in all over the place with all of this 350-pound (159 kg) cotton webbing. When the parachute comes out, it pops out like you or I would pop a thread, and that makes sure that this parachute strings out and inflates correctly every time.

Johnny: But let me ask you something. When these parachutes are deployed and they fall into the ocean, I mean, what do you do with them?

McGugin: Okay, they fall into the ocean, and there's marine operations that goes out and there's two ships that go out. One recovers the parachutes of each booster. The divers go and they get them and they put them on big reels on the back of the parachute, bring them back to us. We bring them back here and we rinse them. We don't really wash them because there's no detergent or agitation, but we rinse them out so that you get all the minerals out of it, 'cause seawater, it's got minerals in it. If you let that dry, it creates a crystalline structure, gets a sharp edge, and it'll mess up your parachute. It'll decrease the strength of the fiber.

Johnny: Sure.

Johnny: So Terry, obviously, there are like a million things that have to go right, you know, but this is, like, one thing that most people don't even think about.

McGugin: Right, this is just one parachute of the parachute system. This is just one process of the recovery system. The recovery system is just one process on the solid rocket booster. The solid rocket booster is just part of the shuttle system, and, of course, once the shuttle system gets up, they have the orbiter that goes up, does the mission, and comes back home to do it all over again. It's a very complex process. I'm really glad to be part of it.

Johnny: Well, you know, Terry, thank you so much for your time.

McGugin: You're welcome.

Johnny: See you around, all right?

[heavy rock music]

Jennifer: All right, so we've scratched the surface a little to show a few things that are happening at the Kennedy Space Center. But you know, when our next-generation space vehicles start flying in a few years, we'll start a whole new chapter in the long history of the Kennedy Space Center. So in the upcoming years, NASA personnel will continue working hard to reach our new national goal of getting us back to the moon and on to mars. And guess what? All of us? We're gonna have a front-row seat for it. That's it for this episode. For Johnny Alonso, I'm Jennifer Pulley. Catch you next time on NASA 360.


* * *


BLOOPERS
 

Johnny: And one of the main goals is to get us ready to go to space. That's not right.

Jennifer: Johnny is at the thermal protection facility system facility-- facility system systems.

Johnny: This is where all the most important-- I'm talking about just getting it ready to fly. Thousands of people have-- messed up the words. Do it again.

Johnny: And if you flip it over... Or you do this. [laughs] not to mention--

Johnny: And not to mention-- and not to mention hundreds of other-- but let me tell you something. It is-- oh, i was gonna say, "it ain't easy." sorry.

Jennifer: For Johnny Alonso, I'm Jennifer Pilley. Catch you next time on NASA 360. I don't even know my name.

Jennifer: That's it for this episode. For Johnny Alonso, I'm Jennifer Pulley. Catch you next time on NASA 360.
 

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