TechStuff Boards the Space Shuttle Program

me upon. It sent me to create that huge block of shows about space travel and spacecraft, and it actually has me thinking about pitching a series to my bosses about kind of a more in depth exploration of the stories behind the various space programs out there, going into more detailed because even though I've done multiple episodes, I've

really only scratched the surface of the stories. So if you would like to hear a mini series, you know, not a ongoing podcast, but maybe a mini series episode or a series of episodes all about the space race and the development of spacecraft and launch vehicles and that

sort of stuff. Let me know. There's no guarantee I'll get it greenlit, but if you guys have an interest in something like that, I can certainly pitch it, particularly if it means I might get to go do stuff like take parabolic flights to experience micro gravity, or or to talk with astronauts and engineers and technicians and rockets scientists. I would love to do all of that, but I'm not gonna continue doing that on this show. That would

be excessive. And there's so much more tech than just the space program, obviously, So we're going to conclude this power block of space material with a discussion about the space shuttle program. The Apollo Soyo's mission that happened in nine was the last we put people up into space until and that's when the first space shuttle flight took place. But just like there was overlap between Mercury, Gemini and Apollo, the space shuttle program actually overlapped with other space efforts.

It wasn't like the Apollo Sayer's mission ended and then everyone said, well that was fun, Let's go make a space shuttle. For one thing, Richard Nixon announced that NASA was working on what would become the space shut program way back in nineteen seventy two. But you could actually argue the history of the space shuttle program goes back way before the Space race. That means to look at the origin of the space shuttle, we once again have

to look at World War Two. So much of what came out of the space race, the space age really got started in World War Two. One of the projects that the Nazis pursued during World War two was the design of an aircraft that could take off from Germany and fly all the way to the United States with the intent of dropping a bomb on US cities. One guy, an engineer named Eugen Sunger, submitted a proposal for an aircraft that he called the Silver Vocal or Silver Bird.

The aircraft was essentially a rocket with wings, and it was meant to take off to fly to a suborbital altitude but above the Karmen line, so it's technically in space, it just wasn't in orbit. And then it would begin its descent and as it would descend and re enter the Earth's atmosphere, it would encounter increased air density and that would provide lift, enough lift for the aircraft to

fly up in another arc. And so you would go from Germany to the United States across the Atlantic Ocean in a series of arcs, sort of like bouncing on the way over. You fly up into that orbital altitude, start to come down, hit the dead ser air use that to bank off of and go back up again and continue your flight that way. Now, it never got built, but the designs were part of the research that Americans

seized as part of Operation paper Clip. And again that was when the United States grabbed up a bunch of scientific assets from Germany, including scientists, and brought them back to the United States. Sunger's concepts would become one of the inspirations for the design of the Space Shuttle. And while some engineers were working on rockets designed to either put stuff into orbit or more violently, served as a delivery system for a nuclear weapon, others were developing rocket planes.

These aircraft would travel faster than any previous air vehicles, and one such rocket plane, the Bell X one, was the first vehicle to break the sound barrier when Charles E. Chuck Yeager made history on October fourteenth, nineteen. The X one was just the first in a series of rocket planes. One of them, one of the really famous ones, was

the hypersonic X fifteen. In the nineteen sixties, while the Mercury and Gemini missions were going on, the X fifteen rocket plane was smashing records for both altitude and speed.

Those rocket planes became important testing grounds and brought back valuable data for engineers who were interested in creating a spacecraft that could return to Earth by flying back through the atmosphere instead of plummeting to Earth and deploying a parachute, or maybe plummeting the Earth, deploying a parachute and firing

off a last second breaking booster. Those were spacecraft that fell into a category that generally speaking, we could call lifting body vehicles, meaning they were required some sort of launch vehicle to lift them into outer space, and then, like ballistics, they would return to Earth on re entry. So they might have limited capabilities in orienting themselves properly for re entry, but they wouldn't fly under their own

power and land at a designated landing space. They would come in like like a falling rock and deployed parachutes and maybe a breaking thruster, depending upon whether it was the U S or the Soviet versions. It was around this time that NASA and the Air Force decided that the edge of space was actually about eighty and a half kilometers above mean sea level, or fifty miles. Because, of course, the US always likes to measure things in

a way different from everybody else. That puts the edge of space a little lower by US measurements than the international standard, because the international standard is the CARM online, which is at one kilometers above mean sea level. And it also means that any pilot who flew an aircraft that went above fifty miles altitude would receive the honor of being able to wear astronaut wings. So eight different

fifteen pilots earned their astronaut wings in that way. By the nineteen sixties, the US Air Force started work on a new vehicle called the X twenty, also sometimes called the Dina Sore Sore spelled s o A r Hardy har Harror, and it was in many ways similar in design to the later Space Shuttle, and if it had been built, the Air Force would have used it to do stuff like satellite maintenance. The operation got as far as some early construction, but it was ultimately canceled, so

no X twenties were ever finished. The idea of a space plane or a reusable vehicle fit into a general series of steps that the engineer Werner von Braun had recommended. Von Braun was one of the German engineers who had been brought over to the US as part of Operation paper Clip. Though the steps towards establishing a permanent presence in space said this is this is how they should work. According to von Broun, he said, this is this is

the way we should go about this. First, we've got to figure out how to put a person into space. That's our first step. Second step is to figure out the design for a reusable spacecraft, because that's going to bring down the expense and the time it takes to get someone into space. Now, you have probably heard various essiments about how much money it takes to put a certain amount of stuff into space. Like a common one I hear is it costs ten thou dollars to put

one pound of stuff up into space. But really it's way more complicated than that because it all depends upon multiple factors. So those factors include like which launch vehicle are you using and where in space are you going. Different launch vehicles use different types of fuel and that can cost different amounts. Also different amounts of fuel that

also also will impact the cost of launch. They also have different payload capabilities, So if you pick a rocket that can carry more stuff, then it may mean that overall it costs less per unit of mass to send that stuff up there because you're able to send more up at once, and most launch vehicles are one use only, so you have to build a whole new launch vehicle

every time you want to go up in space. So if you wanted to send material up on say the Atlas five rocket, that would cost you about twenty thousand two d per kilogram of stuff, and that's if you wanted to send it into lower th orbit. But if you wanted to use the Falcon Heavy launch vehicle from SpaceX, then it would cost more like one thousand, seven hundred dollars per kilogram, And that's for several reasons. One is that the Falcon Heavy has reusable components. Not the whole thing,

but parts of it are reusable. That helps cut down some costs. And it has an incredible carrying capacity, so it can carry more stuff up. So the more stuff you carry, the more you have to divide that cost up by right, And so that's why the Falcon Heavy is relatively inexpensive when you compare it against other launch vehicles. When you're looking at, you know, the cost of kilogram to put it in lower th orbit. The further out

you want to go. However, the more expensive it will be because if you want the Falcon heavy to send stuff to say Mars, well it can't carry as much. It needs more of its fuel just to propel the spacecraft towards Mars. So then you start seeing the cost go up because you have you can only pack so much stuff onto the launch vehicle before you have exceeded the carrying capacity for that destination. So, like I said, it's a little more complicated than just ten thousand dollars

per pound. Uh. After reusable spacecraft, von Brown envisioned building a space station in orbit to act as a base from which you could then launch expedittions too places like the Moon or Mars. And in fact, that was the plan that engineers had in the nineteen fifties. They said, this is what we're gonna do. We're gonna build a reusable spacecraft. It's going to be kind of a rocket plane. We're going to use this to construct a space station out in orbit, and from there we're going to launch

missions to places like the Moon. And then in nineteen fifty seven, the Soviets launched spot Nick into orbit, and that messed everything up. So the original plan of working on this sort of gradual development toward building a reusable spacecraft in the space station meant that it was just

not going to be acceptable. There was now a very tighter deadline because the United States and the Soviet Union were now in a space race to prove that each country had the technological and military superiority over the other one. Because if you could put something in orbit, it means you could also potentially put a missile at the other country on the other side of the world. You could

make it impact the other country. So there was a very strong political and military urgency behind the development of the space race, and the use of a reusable spacecraft in a in a space station didn't really fit into that narrative. It was going to take too long. So that's why they looked at the more simple approach of these liftoff vehicles that would have the ballistic re entry strategy instead of that gliding technology like a space plane.

And you know, Kennedy had declared in nineteen sixty one that America was gonna put a man on the Moon and bring that man back before the end of the decade, so they had to skip that whole reusable spacecraft in space station part of the plan and go straight to how do we get to the Moon and back without this space station mid step, So the focus switched to the liftoff carrier programs. But engineers had not yet given

up hope on a reusable spacecraft. They still had some pretty big plans, which I will tell you about in just a second, but first let's take a quick break to thank our sponsor. The early version of those plans that I mentioned before the break didn't involve a Space Shuttle attached to an enormous pair of solid fuel booster

rockets like the Space Shuttle ultimately had. Instead, the original space Shuttle design would consist of a two stage vehicle, and each stage of the vehicle had its own pilot crew. So the first stage was a large hypersonic aircraft and it would carry the smaller Shuttle orbiter on its back

piggyback style. So the concept we had the hypersonic plane achieve an altitude of at least fifty thousand feet and travel at incredible speeds before the second stage would launch off of the back of the first stage and then ignite its engines and take the orbiter the rest of the way out into space. The first stage would then return to Earth and land just like a normal plane would, and it would be completely reusable, and the orbiter, once it had concluded its mission, would re enter the Earth's

atmosphere and likewise return to Earth. Which sounds like a supremely cool idea. You would have these re usable components. They would obviously need to be you know, refurbished after every single mission, but you would get to use them over and over again. It was a brilliant and elegant kind of approach, and there have been many proposed spacecraft

designs that have followed in this model. The design was also uh to address one of the big challenges that NASA faced, which was that a winged vehicle made sense right. They wanted a winged vehicle where you could have a controlled glide back to Earth, where you could glide to a predetermined landing spot, a very precise landing spot, not just a general area where you're going to splash down in the ocean. But wings on a spacecraft are a

big challenge. They're a critical part of the vehicle design. But whatever you make them out of has to be really really sturdy stuff, and the forces of re entry are incredible. That's intense pressure and heat, So conventional wings would be really difficult to build in such way that they would be reliable. The fear was that if you made conventional wings like wings attached to a fuselage, they would just rip off or or at least be so

damaged as to be inoperable upon re entry. The solution was to design the body of the shuttle in such a way that the body is kind of molded so that the wings kind of mold out from the body, and the shuttle has what is called a double delta wing configuration. So a delta wing is a wing that's in the form of a triangle. It's triangular in shape, and it's called delta because it resembles the Greek letter delta,

which is a little triangular shape. A double delta wing has a leading edge wing like the the edge that's closest to the front of the aircraft isn't straight on a double delta wing. So with the case of the Space Shuttle, it's got a slight curve to it. If you look at a picture of a space shutter, you'll see what I'm saying. It's not just a uh, it's not just a flat line that extends out from the

sides of the Space Shuttle. At the rear edge of the wings, the backside of the wings, there are special control surfaces called elevants, and these are sections that are kind of like flaps, and they could change their orientation to affect the shuttles pitch, which is what an elevator does on a traditional airplane, not the kind of elevator

you get in in a building, but an airplane. Elevator is typically a part of the horizontal stabilizer on the ill section of an airplane, and you can adjust that to adjust the airplane's pitch. This was built into the wings of the Space Shuttle, but it also could work not just as an elevator, but as an aileron. And ailerons are used to affect the role motion of an aircraft. So the role is you know, pitches is up or down,

nose up or nose down. Role is leaning left or leaning right essentially, and then the yaw, which is sort of the turning left or turning right, not leaning but turning. The yaw of the shuttle would be controlled using a rudder, and that was part of the tail fin in the back the rudder was actually a split rudder, and it could act as a speed brake. It's called a split rudder because it has a left half and a right half.

If you were looking at the rudder from behind, you would see that there's a vertical line splitting right down the center of this rudder, and it could split apart and open kind of like a book like just imagine a book opening its covers. And it would do this on landing in order to act as sort of an air brake to help slow down the shuttle as part of the breaking system when you were returning to the

landing site. Of course, all the airplane like designs of the shuttle are only important whenever it's in the Earth's atmosphere because in space, there's no atmosphere, so there's no lift, there's no air to break against, so none of those systems that work so well in Earth's atmosphere would do you any good at all once you're in space. To maneuver in space, the shuttle has a couple of different systems.

Has the Orbital Maneuvering System or o MS, and it also had i should say had not has the Reaction Control System or r c S. And those are reaction engines, also known as thrusters. They appear as a collection of rocket engines on the back side of the shuttle. There's also one in the forward part of the the shuttle, near the nose uh they're used by the shuttle crew to change the shuttles orbit and rendezvous with other spacecraft or space stations, and the OMS also allows a shuttle

to exit orbit for re entry. The RCS is used to control roll, pitch and yaw when the orbiter is re entering the atmosphere. So having the right orientation with regard to the Earth is of critical importance, obviously, because you want to direct the part of the spacecraft that has the heaviest heat shielding uh in uh in in in such a way that that's what's taking the brunt

of all the heat and pressure of re entry. NASA started developing the O M S engines as early as nineteen seventy three, so it's good to remember that when you look at a space shuttle, what you're really looking at is a collection of hundreds of different subsystems, and each of those had their own teams of designers, engineers, and technicians, all working largely independently of one another. They had to make certain that everything was compatible with each other.

But you had all these different teams working around the same time on these different systems. It was It's an incredibly complicated piece of machinery. So are a lot of different projects. They're all going on during the same time of development. So why didn't NASA proceed with this piggyback design that they had suggested before with the hypersonic plane carrying the orbital Shuttle. Well, the main problem was budget cutbacks.

So in order to keep the Shuttle program alive in the wake of these smaller budgets that NASA was able to secure, they had to make some big compromises. So, just as the Space Agency had to switch gears and focus on a capsule based space program to meet the goal that Kennedy had laid out in nineteen one, they now had to work on a different means of getting the Shuttle up into space because they just weren't gonna

have the budget to pursue this hypersonic plane approach. Uh, So they set that aside, although they would do a glider test that would be somewhat similar to the approach that they had suggested with the hypersonic plane, except, of course, the glider test would be aboard a plane that could not achieve hypersonic travel. I'll talk a little bit about

that towards the end of the episode. So instead, the decision was made to go with rocket boosters to put the Shuttle into a position where it could enter orbit. But it wouldn't involve putting the Shuttle on a full launch vehicle the way the Apollo or the Mercury or the Gemini space capsules were. The shuttle itself would be one component of this overall launch system. So if you were to look at a space shuttle on a launchpad, you're at a distance, you're looking at the shuttle. It's

attached to all of its components. It would look like the shuttle was piggybacked onto a very large rocket on the other side, the far side of the shuttle, and then there'd be two big rocket thrusters on either side of that middle rocket. But that middle rocket isn't a rocket at all. That central cylinder is the external tank. It's a fuel tank. It's just a gigantic fuel tank that carried the rocket fuel necessary for the shuttle's own

primary engines to fire those three main engines. Now, I mentioned in the Rocket Science episode that solid fuel rockets cannot be turned off. Once you ignite them, they burn until there's nothing to burn. So the Space Shuttle booster rockets were two enormous solid fuel rocket boosters, and they were just used for liftoff. Obviously, the orbiter itself had three main engines which used liquid fuel, so they can

be turned on and turned off. The external tank held all that liquid fuel and the oxidizer, so collectively these rocket engines provided millions of pounds of thrust, which was necessary to propel the Shuttle into orbit to achieve that eleven kilometers per second necessary to escape the Earth's gravity. In a bit, I'm going to talk about the launch process, but first let me give you a few more specifications

about the Shuttle itself. A typical crew on a Space Shuttle mission was six or seven astronauts, but the first few missions had a crew of just two astronauts, so you had a commander and a pilot, and two of the missions actually had a crew of eight astronauts, though the second of those, the STS seventy one mission, started with seven crew members. So where did the eighth come from.

How did that happen? Well, the mission went to the Mere Space Station and they brought up to relief cosmonauts who came aboard the space station, and they brought home two cosmonauts plus an astronaut in addition to their regular crew of five crew members. So that added up to eight on the trip home, seven on the way up, eight on the way back. There were three pressurized areas for the crew in the space shuttle. The flight deck was where the commander and pilot would sit. That's where

the forward and rear flight controls existed. So all these switches and and and control sticks and everything that you would see, that's all in the flight deck section. It also could have two seats set behind the commander and the pilot that would give seating for up to four in the flight deck section for takeoff and landing. Then there was the mid deck. The mid deck normally had three more seats in it, so that's where your additional

three astronauts could sit. With your full component of seven for the mission I just mentioned above, in which two cosmonauts returned home two additional ones, so you had eight instead of seven. The crew actually would install two special chairs in the mid deck that were in a sort

of reclined position. Because the two cosmonauts had been aboard the Mere Space Station for a long time, I think more than a hundred days, and they were there was concern about how their bodies would react upon being re introduced to Earth's gravity, so they were put in a special reclined chair that had been made specifically for that purpose. Both of them were in reclined chairs in that mid

deck section. Before taking off, there's a group of astronauts that are not going on that mission who are part

of the process. They verify that every person who is going is properly strapped into his or her respective chair, because frequently, apparently when you're getting ready to go on a Space Shuttle mission, you've got a whole bunch of stuff on your mind, like all the things you need to check before you take off and your mission parameters and things like that, and sometimes that means you forget

to strap yourself in. So this crew had the official designation of the Astronauts Support Personnel or ASP, but some of them were called Cape Crusaders because they did their launches at at Kate Kennedy Kipe Canaveral and astronaut Chris Hadfield, that's the Canadian astronaut. He became famous when he UH shared a YouTube video of him aboard the International Space Station and he was playing the song Space Oddity. He served as a cape crusader a couple of times before

he actually went up in a Shuttle mission. Now, if you look at the top side of a Space Shuttle, you see that split that goes down a large section of the top side. That's the cargo doors. It's a pair of doors, huge cargo doors. They open up to the shuttles cargo bay. The cargo bay is sixty ft long. That's about eighteen meters and fifteen feet wide or four

and a half meters. The heaviest payload the Shuttle ever had to carry up in a mission was twenty five tons, and that was for the Chandra X ray observatory and the upper stage booster for that observatory. The cargo bay on the Space Shuttle also had a robotic manipulator arm that would allow Shuttle crew to deploy or retrieve satellites. So just a giant articulated arm that could that could grab a satellite, pull it from the cargo bay and

place it gently off into space. Pretty cool. Also, it had the docking capability to dock with the International Space Station as well as the Russian Space Station mirror. The shuttle had its own airlock which two astronauts could fit into at a time in order to go into the cargo section where they would work with the satellites and stuff like that. Uh. But if they were docking with a space station, then they would rely upon the space station's air dock that it would connect to a connector

inside the cargo bay. But the astronauts wouldn't pass through an airlock from the shuttle side. They passed through an airlock on the space station side. Electricity on the Space Shuttle was generated by fuel cells. I love talking about fuel cells. I've got a future episode of tech Stuff planned where I will be talking about fuel cells with regard to cars and and uh, you know, terrestrial vehicles and comparing them against electric vehicles, which they're they're very

closely related but super interesting. And they were used as the power source on the Space Shuttle missions. The heat shielding was primarily while he was all over the shuttle. On the entire shuttle was covered by heat shield material, but some of the most potent stuff that The black tiles were on the bottom side of the shuttle and were incredibly efficient and absorbing heat that had a very high capacity for heat. The shuttle had a couple of

forward control thrusters near the nose of the spacecraft. I mentioned that earlier, and on landing, of course, they shuttle would deploy not just the landing gear, but once it touched down, it would deploy a parachute to help it slow down. So the Space Shuttle had a breaking system that included a parachute, It included that split rudder I mentioned earlier, It included other breaks because it was traveling really fast even as it was coming down now after

descending through our atmosphere. Now, when we come back from the break, I'm going to talk about the lift off and landing process that the Space Shuttle went through on its missions and the various shuttles that were in the program, and of course will spend a moment to talk about the two tragic UH Space Shuttle missions that that ended in the loss of the entire crew for both missions. That will come up after this ad break. So let us take a quick break to thank our sponsors. All right,

on the launch pad. If you were looking at the shuttle, the shuttle is upright, so it's it's with the nose facing in the air and the engine facing towards the ground.

That makes sense, right, But that also means that all the chairs inside are such that if you were sitting in the shuttle and you're ready for launch, you're essentially on your back looking up, which is a good position because you're braced for a liftoff, but it also means that when you are coming in for landing, the chairs are in the normal upright position that we Earthlings tend to be in, which makes sense, and the bottom of

the shuttle will make contact with the ground. If you've ever watched a launch, you've likely heard the countdown and probably a whole lot of chatter as various people go through an exhaustive checklist to verify that everything is a go for launch, and technicians, all of their in charge of their various systems technically had the power to give a go or no go based off the readings they

were getting from their individual respective sensors and equipment. So if something looked wrong, they could say no go, there's a there's a problem, and then the process would stop. If it was a fixable problem, technicians would try to fix it and verify that the fix worked and the process would start up again. Otherwise thelaunch would have to be scrapped. The same was true about whether if the weather was not right for a launch, they could hold

for a little bit. But there's a limited window for a launch to happen where the shuttle is going to enter orbit at the proper spot in order for it to conduct its mission, So bad weather can completely scrap a launch as well and force everyone to go for the next day. On the launch pad, an orbiter access arm provides a walkway to the shuttle's cabin. That's how you board the shuttle. So the launch pad has a tower and that tower has an orbiter access arm or

walkway that connects to the shuttle. So at tea minus seven minutes thirty seconds, the order would be given to retract that arm. At team minute team minus five minutes, so five minutes up from liftoff, the commander of the shuttle would give the order to start the auxiliary power units aboard the shuttle. They would receive this order from ground control and then they would start to power up

the auxiliary power units on the shuttle itself. At TEA minus two minutes, the crew would give be given the order to close their visors for their launch and entry suits, the pressurized suits that they would wear in case of some emergency de pressurization so that they could survive such

a thing. At team minus thirty one seconds, assuming everything is cool, the go command is issued and the auto sequence start begins, which hands off primary control of the countdown to the shuttles computers from ground control to shuttle. At team minus sixteen seconds, they would activate these sound suppression water system. And I mentioned this earlier, So the system absorbs sound to help prevent acoustic damage to the shuttle.

So it's not just thinking, oh what about the neighbors, it's literally the engines create so much vibration, so much sound, that it could potentially damage the spacecraft itself, and so this water system is meant to absorb some of that vibration. It's flowing water through a big system that can accept that vibration and thus dampen it a little bit. At T minus uh six seconds, the engines all fire up.

Each of the three engines on the main orbiter start I should say all the engines on the orbiter start up the main engines at tea zero seconds. That's when the solid fuel boosters ignite. So those rocket boosters on either side ignite their solid The thrust is incredible. The bolts holding the shuttle to the ground are released in a little explosion, and the bolts all pop off and the Shuttle takes off into the sky through the power

of rocket science. Now at the end of a mission, so during the mission, the Shuttle crew does whatever they're supposed to do, like maybe they're deploying a satellite. Maybe they're doing repair work on the Hubble Space telescope which was wired a couple of times. Maybe they're visiting the International Space Station, maybe they're changing crew out on the

space station, whatever the parameters might be. At the conclusion of a mission, the Space Shuttle orbiter, once it's in the proper uh position relative to the Earth, would close its cargo bay doors. It would fire the RCS engines in order to maneuver into the proper orientation so that would be facing tail first toward the Earth, and then it would fire the O M S engines to slow down the orbiter, and by slowing down it causes your

orbit to decay. Right, if you're no longer going orbital speed, you start to descend and you begin to re enter the Earth's atmosphere. It actually would take about twenty five minutes from that reorientation uh to actually make contact with the upper atmosphere. So it's not like they reordered ordered themselves. Tell first fired an engine and then immediately they were falling. I mean technically they were kind of falling, but not in the Earth's atmosphere. It would take another twenty five

minutes to get there. During that process, the crew would fire the RCS engines several more times to adjust the shuttle's orientation again so that the bottom of the shuttle would face the Earth. So while they would be tail first for the essentially the breaking process, they would reorient to be bottom facing the Earth for the re entry process, and they would also point the shuttle so that it

was nose first again. The crew would also burn any leftover fuel in the forward RCS engine as a safety precaution, because the nose section of the shuttle was going to end up being the the site for a lot of heat and they didn't want to have any accidental ignitions. Of any leftover fuel, so they burn off the fuel the excess fuel on purpose. At that point, the heat shielding absorbs that intense heat with getting too hot themselves. It's pretty amazing the heat capacity of those those tiles

that were used on the Space Shuttle. The Space Shuttle had aft steering jets that would help keep the shuttle at the proper forty degree attitude upon landing or re entry, i should say, and once the orbit was low enough in the atmosphere, it could start to glide. Once the atmosphere and once it reached a density that was sufficient to provide lift, the shuttle could go into glide mode

at about two thousand feet altitude. The commander would pull up on the nose, which helps slow the descent of the shuttle, and the pilot would deploy the landing gear. Upon touchdown on the landing strip, the uh the pilot would engage the brakes and deploy a parachute, and the vertical split rudder would open up to act as an air brake, and the shuttle would come to a halt somewhere maybe halfway to three quarters down the landing strip. Then the crew would go through a power down sequence

powering down all the different systems aboard the shuttle. That would take another twenty minutes or so, and at that point they could finally get out and touch foot back down to Earth. The shuttles in the program included one called the Enterprise. That one was never designed to go into orbit. It was a test vehicle. Uh it was used for gliding tests, and it piggybacked on a specially

outfitted seven forty seven. So this is the one I mentioned that was close to that original design for the Space Shuttle, except, of course a seven forty seven is not a hypersonic aircraft, so it never would have been able to launch off a seven seven in the way that the original engineers had planned, but it did use one to launch from for gliding tests. The shuttles that were in active use were the Discovery, the Endeavor, the Atlantis,

the Challenger, and the Columbia. And the Challenger in Columbia were two of the awful tragedies in the United States Space Program. I had talked about a few of the others and some of the other episodes. These two were also terrible, terrible losses, and they both resulted in the death of the entire crew aboard on each of their respective missions. The Challenger exploded during STS five one l It was the tenth mission for the Challengers. The Challenger

had already been on nine other missions successfully. A seal on one of its rocket boosters failed and that allowed hot gas to burn through and pierce the external tank, the one carrying all the fuel and oxidizer and propellant, and it caused an explosion and the loss of all aboard. The Columbia broke apart during re entry on the mission STS one oh seven. That was the twenty mission for

the Columbia. The Endeavor would be entered into service after the Challenger and all in all, through the entire space program, there were one five Space Shuttle missions that took place between and when the program ended in two thousand eleven. The Discovery now calls the Dvar Hazy Center at the Smithsonian Home. The Endeavor is over at the California Science Center in Los Angeles. The Atlantis is at the Kennedy Space Center, and you can see a full sized replica

of the Space Shuttle at Space Center Houston. That one is called the Independence, but it's a replica. It did not go into space. UM now I'm going to take a quick tangent to talk about the launch vehicles developed by SpaceX. I mentioned this in the last episode, but that episode was raring super long, so instead it's going to go in this one, which I'm sure we'll also

run super long. But the last two launch vehicles that I need dimension uh, that were are will be responsible for taking crude as in manned missions up into space are the Falcon nine and the Falcon Heavy from SpaceX. Now, before I do, I also have to stress there were a lot of launch vehicles that were planned but never built, and there were a lot of launch vehicles that were

designed for unmanned payloads going into space. And there are tons of countries besides the United States and Russia that have developed launch vehicles, but I focused on US and the uss are because of the Space race angle, and I also focused on the manned missions for the purpose of these podcasts, because again, to go into all of these different launch vehicles would take just take a podcast series all by itself. So let's finish up with the Falcons and rise up, so to speak. The Falcon nine

is a two stage launch vehicle. It's classified as a medium lift vehicle The current version has the designation of Falcon nine Full Thrust, and it is a partially reusable spacecraft. The reusability of components helps bring down those costs, right. That's what I've mentioned before, and so that was one of the big selling points of SpaceX launch vehicles was that they would be at least partially reusable, and um the earliest versions of the Falcon nine rocket launched in June.

The Falcon nine full thrust is two thirty feet tall or seventy meters. It is twelve feet in diameter or three point seven meters. I can carry payloads of up to four thousand, twenty ms or eight thousand, hundred sixty pounds if you want to go to Mars. If you think Mars is too far and you just want to go to low Earth orbit, you can actually pack up to twenty two thousand, eight hundred kilograms or fifty thousand,

three hundred pounds worth of stuff on it. So I mentioned that earlier too, is that the amount of stuff you can carry on a launch vehicle also depends on where you want to go. The further out you want to go, the less stuff you can take. The Falcon heavy like the Falcon nine is partially reusable, and it's

crazy big. So if you look at a Falcon nine launch vehicle, just imagine having two other first stage Falcon nine launch vehicles next to the middle one and and strapping them together, and you've got yourself a Falcon Heavy. The Falcon Heavy is essentially a Falcon nine at the core, flanked by two Falcon nine first stages as booster rockets. It's one of the most powerful launch vehicles ever designed. It currently is the the only or currently it can

carry the heaviest payload out of all active launch vehicles. Um, it's the fourth most powerful of all time. It's right behind the Saturn five. The Saturn five was the launch craft that was responsible for taking astronauts to the Moon, and so it had a little bit more oomph than the Falcon Heavy. Uh. There are a couple of other launch vehicles in the past that would also outperform the Falcon Heavy on paper, but none of those are in

active service right now. The Falcon Heavy is the same height as the Falcon nine because it's using that same rocket essentially as its core, but those two extra first stages make it much wider because you know, it's got one on either side of it. Its capacity means it can carry sixty three thousand, eight hundred kilograms or one hundred forty thousand, seven hundred pounds to low Earth orbit, an enormous payload. Now, if you want to go to Mars,

you gotta slim down a little bit. You can have a payload of sixteen thousand, eight hundred kilograms or thirty seven thousand pounds. Let's say you want to go all the way out to Pluto. Well, then you have to slim down even more. You know, you could have as much as three thousand, five hundred kilograms of payload, which is the same as seven thousand, seven hundred pounds. A lot of that better be lunches, because it's gonna take

you a really long time to get to Pluto. The Falcon Heavy has had only one test flight as of the recording of this podcast. Asked that was when Elon Musk sent his Tesla Roadster on a trip to Mars. I guess he got tired of the mechanics, saying they

couldn't replicate whatever the problem was or something. But in the driver's seat of this Tesla Roadster was a dummy wearing a SpaceX space suit and it had the name star Man, and the cars sound system was set to play a loop of space Oddity and Life on Mars to David Bowie songs. Uh, although I have to admit in space no one can hear you listen to clam Rock. And that wraps up are huge block of content about space travel. Obviously, there are a lot of other things

we could talk about. Space sales, we could talk about, you know, the gravity towing. There's tons of different stuff in space that's super cool. But some of it I've covered before, and other topics I'm sure i'll cover in future episodes. If you have any suggestions for topics I should cover, please let me know. Send me an email. The address is tech Stuff at how stuff works dot com. Don't forget, We've got a merch store over at t public dot com slash tech Stuff. You can go and

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