“Houston We Have a Podcast” is the official podcast of the NASA Johnson Space Center, the home of human spaceflight, stationed in Houston, Texas. We bring space right to you! On this podcast, you’ll learn from some of the brightest minds of America’s space agency as they discuss topics in engineering, science, technology and more. You’ll hear firsthand from astronauts what it’s like to launch atop a rocket, live in space and re-enter the Earth’s atmosphere. And you’ll listen in to the more human side of space as our guests tell stories of behind-the-scenes moments never heard before.
Episode 25 features Wahab Alshahin, Guidance, Navigation and Control Engineer, who talks about what a launch abort system is, how it works, and why it’s necessary to send humans to space. This episode was recorded on July 12, 2017.
Transcript
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Gary Jordan (Host): Houston We Have a Podcast. Welcome to the official podcast of the NASA Johnson Space Center. I’m Gary Jordan, and I’ll be your host today. So before we cross into the new year and witness the spectacle of thousands of fireworks launching everywhere, for Episode 25, we’re talking about rockets — specifically, a special rocket that’s, well, on a rocket. So today, we’re talking about launch abort systems with Wahab Alshahin. He’s a guidance, navigation, and control engineer here at the NASA Johnson Space Center in Houston, Texas, and we had a great discussion about what a launch abort system is, how it works, a little bit of history, and why they’re necessary to send humans into space. So with no further delay, let’s go light speed and jump right ahead to our talk with Mr. Wahab Alshahin. Enjoy.
[00:00:43]
[ Music ]
Host:But Wahab, it’s actually, it’s really good to see you, and thanks for coming on the podcast today, for taking the time to do this.
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Wahab Alshahin: Yeah, of course.
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Host:This is an interesting topic because it’s sort of, you know, we were talking a lot about a lot of big things, right. We were talking the International Space Station. We talked about space food, landing, these big concepts, but this is sort of, it is a big concept, but it’s kind of like, you know, if you’re looking at a rocket, you’re looking at the tippy, tippy top of a rocket.
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Wahab Alshahin: Yeah.
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Host:So, yeah. I mean, that’s kind of what we’re, what this is, right? This is about, I titled this “A Rocket on a Rocket.” Is that a fair way to say it?
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Wahab Alshahin: That, so when you–
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Host:Okay.
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Wahab Alshahin: Told me that you mention, or you were trying to call it a rocket on a rocket, I thought about that, and then I thought about the specifications for what this thing actually does.
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Host:Yeah.
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Wahab Alshahin: It’s 30 feet tall. It produces 400,000 pounds plus or thrust.
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Host:Whoa.
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Wahab Alshahin: That is basically, you, at that point, yes, that is a rocket that is sitting on top of an even larger rocket. [laughs] Yeah, so certainly, that’s a fair assessment. Yeah.
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Host:Wow, all right.
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Wahab Alshahin: Yeah.
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Host:Yeah, I didn’t think, because I was like, it kind of is, right, because the whole point of this is it’s called a launch abort system, correct? So–
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Wahab Alshahin: That’s right.
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Host:If a rocket is launching and something goes wrong, there is another rocket on top of it that could safely get our crew members away.
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Wahab Alshahin: That’s correct.
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Host:Is that kind of the overall concept of why this is what it is?
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Wahab Alshahin: Yeah, yeah.
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Host:Okay.
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Wahab Alshahin: So with regards to the capability, yeah, it is, the primary purpose is to separate the crew module from the launch vehicle that may or may not be having a problem. So whether or not you use a tower or you have built-in engines like some of our private partners, like SpaceX and Boeing have built-in engines as opposed to tower–
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Host:Oh, okay.
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Wahab Alshahin: That’s up to the design engineers, but form, first and foremost, it’s separating the crew from the failing launch vehicle. That’s the primary purpose.
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Host:Awesome. So that’s, yeah, that’s kind of the overarching, you know, what is the purpose of this?
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Wahab Alshahin: That’s right.
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Host:That’s pretty much it, okay. So like you said — what was that number you said at the very beginning? How many pounds of thrust?
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Wahab Alshahin: So for the Orion launch abort system–
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Host:Okay.
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Wahab Alshahin: The abort motor that separates that crew module from the launch vehicle generates about 400,000 pounds of thrust.
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Host:Whoa.
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Wahab Alshahin: Yeah.
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Host:Okay.
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Wahab Alshahin: Yeah, so [laughter] it is–
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Host:That’s a lot.
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Wahab Alshahin: Yes, yeah.
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Host:Wow. What, compared to, I mean, when you think about it, you’re talking about, it’s called aborting a launch, right? So really, you’re escaping–
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Wahab Alshahin: That’s right.
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Host:From a speeding rocket.
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Wahab Alshahin: That’s right.
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Host:Right? So what kinds of, what, that’s the energy that really has to go into that, so how does that happen?
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Wahab Alshahin: Yeah. So again, so I work on the Orion launch abort system.
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Host:Okay.
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Wahab Alshahin: So speaking from what we’re doing on that project, but–
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Host:Okay.
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Wahab Alshahin: Like I said, there are different kinds of launch abort systems and people do things differently. But in general, you have to be able to provide capability to separate from the rocket all the way from when it’s on the pad, essentially prior to launching, up to prior to going into orbit. So that design space is zero feet in altitude to 300,000 feet in altitude and traveling at zero miles per hour to seven times the speed of sound.
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Host:Whoa.
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Wahab Alshahin: So you’re, a single system has to be capable and robust enough to provide abort capability throughout that entire spectrum.
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Host:Okay.
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Wahab Alshahin: So you can imagine, yeah, you have to have enough thrust capability to separate when you’re not moving, but also when the vehicle is traveling at thousands of miles per hour.
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Host:Whoa, okay.
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Wahab Alshahin: Yeah.
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Host:But there’s, like, okay, so you said — you kind of hinted at this — there’s different types, right, and so for you specifically, you’re working on Orion.
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Wahab Alshahin: That’s right.
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Host:And I can’t believe it, but up until this point, we actually haven’t had a podcast that’s just the overall concept of Orion. We’re actually starting with the launch abort. So let’s–
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Wahab Alshahin: Okay. [laughs]
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Host:Go back, and let’s talk about, you know, what is Orion?
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Wahab Alshahin: Sure.
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Host:What are you designing this launch abort system for?
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Wahab Alshahin: All right. So in general, Orion is the crew module that is built, that’s going to be built to house our astronauts and take them to low Earth orbit as well as our deep-space missions, so whether that be to the Moon or Mars.
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Host:Okay.
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Wahab Alshahin: So that’s just the capsule itself.
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Host:I see.
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Wahab Alshahin: The part that I work on is the tower that is attached at the top of the crew module, which is on top of the large space launch system, which is our rocket. So–
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Host:Okay.
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Wahab Alshahin: Yeah. In total, the rocket plus the crew module plus the abort system is about 330 feet high.
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Host:Okay.
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Wahab Alshahin: Yeah, so it’s a [laughs] big rocket, yeah.
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Host:Yeah. That’s like a tall building.
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Wahab Alshahin: That is basically a tall building. That’s right.
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Host:Yeah, that’s amazing. Okay, cool. So you’re, if I’m imagining, so the Orion capsule, right. I, if I were to imagine a shape, I’d kind of imagine it mostly like a capsule or like sort of the rounded trapezoid. Is that a fair–
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Wahab Alshahin: A rounded trapezoid is definitely fair.
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Host:Is that kind of the — yes.
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Wahab Alshahin: Yep, that’s right.
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Host:So if–
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Wahab Alshahin: Yeah.
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Host:You’re imagining a rounded trapezoid with the angles inward going, or the angles on the side going up, you kind of just fit this you said tower right on top of it?
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Wahab Alshahin: That’s right, yeah. And, or the Orion design actually calls for a shroud that actually encompasses and goes around the Orion or Orion crew module itself. So we have a shroud that covers the capsule.
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Host:Okay, so it’s not just–
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Wahab Alshahin: Yeah.
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Host:A tower–
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Wahab Alshahin: Yeah.
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Host:A pole sticking up. You have, you’re actually–
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Wahab Alshahin: That’s right.
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Host:Covering the–
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Wahab Alshahin: Yeah. Previously–
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Host:Okay.
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Wahab Alshahin: Previously, for Apollo and Mercury, it was just the tower.
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Host:I see.
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Wahab Alshahin: But we opted for a shroud instead for better aerodynamics.
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Host:I was just about to ask why, but–
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Wahab Alshahin: One reason.
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Host:Okay, okay. Very cool.
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Wahab Alshahin: Among others.
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Host:All right, well–
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Wahab Alshahin: Yeah.
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Host:So, okay, so the idea is that, like you said, the purpose is to safely get the crew away from a speeding rocket or in several different scenarios, right.
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Wahab Alshahin: Yeah.
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Host:So what needs to happen, right, just in general talking about the general concept of launch abort system? It’s not just fire a rocket and just go wherever you need to go, right? There’s some intricate engineering that goes into that.
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Wahab Alshahin: That’s right. I call it an abort ballet, yeah. [laughs] It is, it’s definitely, this is one of, probably one of the hardest things to work on in engineering.
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Host:Wow.
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Wahab Alshahin: Like I said, just because you have to design something that’s so robust, that’s built to work in any contingency failure, so it’s kind of like a Murphy’s law. You have to assume what can go wrong will go wrong.
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Host:Yeah. You have to be the devil’s advocate.
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Wahab Alshahin: But–
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Host:Every situation.
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Wahab Alshahin: Exactly.
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Host:Yeah.
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Wahab Alshahin: Exactly, so for Orion specifically, there’s three motors, so let’s just think, visualize this in your head. You’re–
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Host:Okay.
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Wahab Alshahin: Going up on the rocket and you’re at some altitude, you know, barreling toward space. Your mission’s fine.
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Host:Okay.
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Wahab Alshahin: Something happens, and there’s a, either a software switch or some kind of signal that indicates that there’s something wrong with the launch vehicle. That gets sent to the flight computer. The flight computer says, all right, we need to escape. As soon as that command is sent, the abort motor burns, is ignited, and it starts burning, and that burns for about five seconds, and that does the heavy lifting of separating the crew module from the launch vehicle.
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Host:Is that, is it fair to say that’s the most powerful–
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Wahab Alshahin: That’s right. It definitely is.
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Host:Okay.
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Wahab Alshahin: Yeah, yeah. The abort motor is, it’s completely passive. It’s not controlled in any way. It just fire and go. It just separates the crew module from the launch vehicle.
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Host:So there’s no big, red Abort button in the scenario, right?
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Wahab Alshahin: There is not, no.
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Host:It’s automatic.
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Wahab Alshahin: This is all automatic.
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Host:Okay, okay.
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Wahab Alshahin: That’s right. So once we’ve separated, there’s another motor that’s on top of the — it kind of acts like a very large lever arm at the top of the 30-foot abort tower, and that’s the attitude control motor. It’s the most complex motor of the three that are inside in the launch abort system. And the purpose of that one is to literally flip, you’re basically doing a front flip in midair of the crew module because if you imagine we just separated, we’re facing with the tower pointed forward. In order to deploy the parachutes, we have to go heat shield forward. So we have to do an entire 180-degree reorientation maneuver so that the capsule is falling blunt end first.
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Host:Whoa, okay.
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Wahab Alshahin: Yeah.
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Host:So you fire the super-powerful rockets to get away from the larger rockets that you’re–
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Wahab Alshahin: That’s right.
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Host:On top of, and then you fire more rockets so that you do a front flip–
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Wahab Alshahin: That’s right.
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Host:And get oriented. Okay.
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Wahab Alshahin: Yeah.
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Host:So it’s very complex.
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Wahab Alshahin: Yep, and then once you’re, once you are in the orientation that you want for deploying the parachutes, there’s a third motor, that jettison motor, that actually separate, now there’s another separation of the–
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Host:Yeah.
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Wahab Alshahin: Launch abort system, which you no longer need–
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Host:Because it already did the front flip.
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Wahab Alshahin: From the — that’s right–
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Host:Yeah.
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Wahab Alshahin: From the crew module.
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Host:Okay, cool.
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Wahab Alshahin: Yeah. So there’s three separate motors on the launch abort system that have nothing to do with getting you to space. [laughs] Yeah.
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Host:It’s just to get you away from–
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Wahab Alshahin: That’s right.
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Host:This rocket that–
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Wahab Alshahin: That’s right.
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Host:Doesn’t, I guess is not going to take you to space anymore.
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Wahab Alshahin: Yeah.
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Host:So the launch abort system is just a series of motors, a series of rockets, right? The parachutes are completely separate?
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Wahab Alshahin: That’s right.
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Host:Once it does that separation, then the parachutes are coming from the capsule, so–
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Wahab Alshahin: Yeah. Yeah, exactly.
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Host:Okay.
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Wahab Alshahin: And depending on how high we are in altitude, the parachute sequence is no different than what it would be if we were coming back from a mission. Say we had a successful mission and we were deploying the parachutes. It goes through that same process.
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Host:Nice.
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Wahab Alshahin: Yep.
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Host:Okay, so there has to be a lot of, there has to be a story behind how you got to this, did you say rocket ballet? Is that what you called it?
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Wahab Alshahin: Yeah.
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Host:It’s, yeah, is–
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Wahab Alshahin: Or abort ballet.
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Host:Abort ballet, yeah. There has to be a story to it. So what, how was, how did launch abort systems come about? What was the initial, you know, design of this system?
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Wahab Alshahin: Yeah. So obviously, it was first conceived when we were thinking about human spaceflight, so back in the 1950’s and ’60’s during the Apollo mission.
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Host:Okay.
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Wahab Alshahin: So that was first and foremost. We knew that this was a dangerous field, especially back then doing it for the first time. We didn’t necessarily expect failures, but we knew that those were a high, they were high in likelihood.
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Host:Yeah.
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Wahab Alshahin: So we had to design something to save the crew in the event of one of those emergencies. So that’s kind of where it all started. And ever since then, we’ve, every human-rated abort vehicle, or, I’m sorry, every human-rated vehicle that goes to space has to have a escape mechanism, and that’s, that just varies across different people who are designing it.
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Host:Nice. Okay, so how did they, you know, what were some of the early designs, and kind of how did you go from those early designs to more modern? Like, what did you learn along the way?
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Wahab Alshahin: Yeah. So all of the early designs, and by early designs, I’m talking about the early Soyuz, Mercury, Apollo, all those were a tower design.
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Host:Okay.
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Wahab Alshahin: So however that was conceived, people decided that was the way to do it. It made the most engineering sense. Just something to pull the capsule away from the launch vehicle that–
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Host:Right.
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Wahab Alshahin: That’s failing. So all those kind of operated the same way. And for all those systems, they’re all passively controlled. So they’re not actively controlled. So the motors are not controlled in any way. They just burn, and separate the crew, and then dispose of the crew capsule so that it can separate, deploy the parachutes.
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Host:Okay.
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Wahab Alshahin: Yeah. So all those are passively controlled. We’ve kind of moved into the world of active control, so that’s where we are now. The, like I said, the Orion launch abort motor, launch abort system, sorry, is completely, the attitude control motor portion of it that actually steers the abort motor–
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Host:The front flip.
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Wahab Alshahin: Yep, the front flip, [laughs] is controlled. Yeah. You would not be able to do that with a passive system.
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Host:Okay.
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Wahab Alshahin: So that’s actively controlled.
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Host:So for different rockets, there have to be different designs, right? So the tower design seems to be pretty, a pretty good one for–
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Wahab Alshahin: Yeah.
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Host:A upward-facing rocket. I know something had to change for the shuttle arrow, right?
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Wahab Alshahin: That’s right.
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Host:Okay.
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Wahab Alshahin: Yeah, so the shuttle arrow was a little interesting because it was basically a, you know, a space plane, essentially, that was attached to the side of an external tank and two solid rocket boosters. And unfortunately, I don’t think we had, we definitely don’t have as great of abort capability on the abort, or, I’m sorry, on the space shuttle as we do on Orion. Kind of one of the main reasons we’ve shifted back towards toward the long, monolithic rocket with the capsule on top.
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Host:Sure.
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Wahab Alshahin: It’s just a safer design in general.
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Host:Yeah.
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Wahab Alshahin: And most people don’t know this, but for the space shuttle, you could not do an abort from the space shuttle stack until the solid rocket boosters were completely burned out–
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Host:Oh.
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Wahab Alshahin: Which–
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Host:So even, you had to keep ascending–
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Wahab Alshahin: That’s right.
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Host:Wow.
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Wahab Alshahin: There was no abort capability until the solid rocket motor, solid rocket boosters burned out, which was about two-and-a-half minutes.
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Host:Oh, wow.
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Wahab Alshahin: So two-and-a-half minutes, that puts you at about, I don’t know, 140,000 feet.
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Host:Wow.
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Wahab Alshahin: That’s basically halfway up to the current abort capability. I mean–
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Host:Yeah.
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Wahab Alshahin: I mentioned earlier the Orion launch abort system is capable up to 300,000 feet, so half of that is about 150.
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Host:Right.
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Wahab Alshahin: So for half of that entire region, you couldn’t abort. But now, with this system, post space shuttle, we can. We have that–
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Host:There you go.
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Wahab Alshahin: Abort capability.
[00:13:10]
Host:And your window’s that much smaller, right–
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Wahab Alshahin: Right.
[00:13:12]
Host:Because you’re constantly accelerating up there. So even the window from 150,000 feet to 300,000 feet is–
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Wahab Alshahin: Right.
[00:13:17]
Host:That’s a quicker window.
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Wahab Alshahin: Exactly, exactly. Yeah, so again, that was, that’s kind of a side topic, but one of the reasons we–
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Host:Yeah, right.
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Wahab Alshahin: Went back to the stack monolithic approach.
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Host:Got it, sure.
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Wahab Alshahin: But for our design, the, like I mentioned this earlier, if we don’t have an abort, that entire abort tower and those, all those motors are just jettison. We don’t use them at all. So they serve no purpose outside of an abort.
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Host:I see.
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Wahab Alshahin: Yeah.
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Host:When are they jettisons? If, for an Orion mission, right. Say the Orion, the SLS is on top of–
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Wahab Alshahin: Yeah.
[00:13:44]
Host:Is the rocket, right. Space launch system. That’s the one that we’re designing and you put the–
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Wahab Alshahin: That’s right.
[00:13:48]
Host:Orion right on top. Everything goes according to plan. You’re in space. You’re doing your thing. At what point is the launch abort system going to say, I’m not needed anymore; I’m going to detach?
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Wahab Alshahin: Yeah, like, it’s a little after 300,000 feet. And at that–
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Host:Oh, okay.
[00:14:01]
Wahab Alshahin: Point, you could still have an abort. We just wouldn’t use the launch abort tower. We would use the service module.
[00:14:06]
Host:Oh, okay.
[00:14:07]
Wahab Alshahin: Yeah, so that would–
[00:14:08]
Host:So that’s the part that, if you’re looking at the rocket, is underneath it.
[00:14:11]
Wahab Alshahin: That’s right. Yep.
[00:14:12]
Host:I see, okay.
[00:14:13]
Wahab Alshahin: And so we would use that engine for an abort to orbit or something like that.
[00:14:16]
Host:Okay.
[00:14:17]
Wahab Alshahin: Yeah.
[00:14:17]
Host:Okay.
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Wahab Alshahin: So at that point, you are, your requirements aren’t necessarily, come back to the Earth. It’s, you are high enough that you can abort to orbit, some low Earth orbit and, or not low Earth, but some lower orbit, and then come back.
[00:14:28]
Host:Yeah, it’s not like, oh, I need to get back right now–
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Wahab Alshahin: That’s right.
[00:14:30]
Host:With launching. Okay, okay. So you got some time, and you have to, your, it’s different physics, right? Now you’re in orbit. Now you’re–
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Wahab Alshahin: Yeah, yeah. There’s, yeah, there’s no air drag, or very little, rather.
[00:14:39]
Host:Yeah, so you’re talking about a whole nother thing. We’ll have to do another podcast now.
[00:14:42]
Wahab Alshahin: That’s right. [laughter]
[00:14:45]
Host:Okay, very cool. So, you know, going back to Orion, we talked a little bit about, you know, the history of launch abort. It seems like it was this tower, and let’s just keep improving it. So, you know, what is — we’ll get into the weeds in a little bit — what are some of the cool things? You mentioned a shroud.
[00:15:01]
Wahab Alshahin: Yeah.
[00:15:01]
Host:Shroud is one of the things that’s different about Orion, but what’s some of the other parts that are different?
[00:15:06]
Wahab Alshahin: From the heritage technology that we were, the heritage designs that we had in the past, we being NASA–
[00:15:12]
Host:Okay.
[00:15:12]
Wahab Alshahin: The biggest thing is actively controlling this. Yeah.
[00:15:14]
Host:The front flip. I keep going back to that.
[00:15:16]
Wahab Alshahin: So it is, that’s, yeah. It’s a, you can call it front flip, fine. It, the entire system has its own flight computer and flight brain, so that’s just, it’s one extra level of complexity. And like I said, being an engineer on the project, it’s really interesting to kind of work on it day in, day out, but there, you have to design, you have to overdesign everything because you don’t know–
[00:15:41]
Host:Yeah.
[00:15:42]
Wahab Alshahin: How this thing is going to be used. So in the event that we have to use this, it implies that the launch vehicle had exploded, had failed, had broke up.
[00:15:51]
Host:Right.
[00:15:51]
Wahab Alshahin: Something was happening that triggered an abort. So you had no idea whether or not you’re facing down, facing up, falling forward. It’s just, you could be at any condition.
[00:16:00]
Host:Yeah. You’re talking about — I don’t, I can’t even think of a number — you’re talking about a lot of different scenarios–
[00:16:07]
Wahab Alshahin: That’s right.
[00:16:07]
Host:And it has to work in all of them.
[00:16:09]
Wahab Alshahin: That’s right.
[00:16:09]
Host:Interesting, okay.
[00:16:10]
Wahab Alshahin: Yeah.
[00:16:11]
Host:So I think you may have addressed this before, but I’m going to come back to it, but, you know, there’s a reason that Orion does this move, has the active motor, has the ability to do a front flip. Why did some of the older rockets not need that? Why were they only passive?
[00:16:28]
Wahab Alshahin: So some of those engines, they didn’t necessarily acquire a, the pitch over portion of the abort, so they–
[00:16:35]
Host:Okay.
[00:16:35]
Wahab Alshahin: Would actually separate, and it was kind of a pointed in a direction, the engines were pointed in a direction to separate you out and away.
[00:16:42]
Host:Oh, so no matter what, it was going away.
[00:16:44]
Wahab Alshahin: It was going away.
[00:16:45]
Host:
[00:16:45]
Wahab Alshahin: Right, yeah. So this is a little more intricate, and we have more requirements for it.
[00:16:50]
Host:I see.
[00:16:50]
Wahab Alshahin: Yeah.
[00:16:51]
Host:Does it have anything to do with the fact that we are talking about escaping from a much larger, much bigger rocket?
[00:16:56]
Wahab Alshahin: No, not necessarily.
[00:16:57]
Host:Very cool.
[00:16:57]
Wahab Alshahin: Yeah.
[00:16:58]
Host:So what are some of the challenges of designing an active system? You said, like, there’s a lot of computer work that goes into it–
[00:17:04]
Wahab Alshahin: Yeah.
[00:17:04]
Host:But what are some of the things that you’ve encountered?
[00:17:07]
Wahab Alshahin: Be, the portion that I told you about, like designing for Murphy’s law.
[00:17:10]
Host:Oh, yeah.
[00:17:10]
Wahab Alshahin: It’s, you just, we end up using a lot of time to run simulations for all of these contingency scenarios that we would otherwise, you know, it’s hard to say what will go wrong, so we just design for everything.
[00:17:23]
Host:Yeah, yeah.
[00:17:24]
Wahab Alshahin: So it’s quite complex to make sure that, oh, I have this great idea for design. You put it in. It’s like, oh, okay, that’s great, but it only works in this small region. It has to work for–
[00:17:33]
Host:Yeah. A bunch of different scenarios–
[00:17:35]
Wahab Alshahin: Yeah.
[00:17:35]
Host:That can happen–
[00:17:36]
Wahab Alshahin: That’s right.
[00:17:36]
Host:Up to 300,000 feet, right?
[00:17:38]
Wahab Alshahin: Yeah.
[00:17:38]
Host:So you got to think of everything in that space.
[00:17:40]
Wahab Alshahin: Yeah. And to take it away from technical — you’d appreciate this — another challenge of working on a launch abort system, so I’ve been at NASA full time for over six years now–
[00:17:50]
Host:Okay.
[00:17:50]
Wahab Alshahin: And this is kind of my main project, and I’ve done some other work on some other vehicles. But the Orion launch abort system has been my main project. So for six years of my full-time experience here at NASA, I’ve worked on something — it’s weird to say — but I’m working on something that I hope never flies–
[00:18:06]
Host:Oh, yeah.
[00:18:07]
Wahab Alshahin: Because if we ever had to use this thing, it implies that, like I said, the launch vehicle–
[00:18:11]
Host:That something–
[00:18:12]
Wahab Alshahin: We lost the mission–
[00:18:14]
Host:Went wrong.
[00:18:14]
Wahab Alshahin: And you’re putting the crew’s life in jeopardy. It’s nothing you want to — even if it succeeded, it–
[00:18:20]
Host:Yes.
[00:18:20]
Wahab Alshahin: The mission’s failed, and now we have to figure out what happened on the launch vehicle. So it’s never going to be a good day when we have to ever use it, so any mission that we have in the future, I’m going to be happen that we didn’t fly it.
[00:18:33]
Host:But, I mean, what you’re saying makes sense because you just said, you know, there’s so many different scenarios that could happen, so–
[00:18:38]
Wahab Alshahin: Yeah.
[00:18:38]
Host:What’s the thing that you have control over? Let’s just over engineer it. [laughs] Let’s design for everything, and that’s your responsibility, and it’s a big one, right, because–
[00:18:46]
Wahab Alshahin: Yeah.
[00:18:47]
Host:You hope it never flies, and that’s a good way of saying it.
[00:18:50]
Wahab Alshahin: Yeah.
[00:18:50]
Host:Absolutely, because that means we’re doing everything perfectly. Thumbs up. A-okay. But if it does, then you know this thing is going to work.
[00:18:58]
Wahab Alshahin: That’s right.
[00:18:59]
Host:Yeah.
[00:18:59]
Wahab Alshahin: Which is why I’m really excited for not actually flying this with humans on board but preplanned flight tests where you actually do perform an abort to test all that capability without humans on board.
[00:19:09]
Host:Oh, okay.
[00:19:10]
Wahab Alshahin: Yeah, so we actually, before I started, we actually did that in 2010. We did a pad abort. So a pad abort is where it’s just sitting, replicating it sitting on the pad, and then performing an abort not, while not on top of the launch vehicle.
[00:19:25]
Host:I see.
[00:19:26]
Wahab Alshahin: Yeah.
[00:19:26]
Host:Okay, so you just set, in this scenario, you just set the launch abort system–
[00:19:31]
Wahab Alshahin: On the ground, essentially.
[00:19:31]
Host:On the ground.
[00:19:32]
Wahab Alshahin: That’s right.
[00:19:32]
Host:And just test it to see if it would work at zero, you know–
[00:19:35]
Wahab Alshahin: Yeah.
[00:19:35]
Host:Like if the rocket was just there sitting, hasn’t launched yet, and — so how’d that go? How’d that–
[00:19:41]
Wahab Alshahin: Fantastic test–
[00:19:42]
Host:All right.
[00:19:42]
Wahab Alshahin: From all the people I’ve talked to that were there and looking at all the design data after the fact, videos — there are tons of great videos on the NASA website and YouTube–
[00:19:51]
Host:Yeah, yeah.
[00:19:52]
Wahab Alshahin: Perfect test. Everything went well, and the design’s kind of matured a little bit since then, but we kind of still do the same thing where we, it’s great video. You can see that front flip I was talking about [laughs] to kind of get a better understanding of what I’m talking about in terms of what’s going on.
[00:20:07]
Host:So was it — going back to, is it just the launch abort system, or was there an Orion capsule–
[00:20:14]
Wahab Alshahin: Oh, yeah.
[00:20:14]
Host:Mock up?
[00:20:14]
Wahab Alshahin: Yeah, there was a boilerplate Orion capsule under there.
[00:20:17]
Host:Nice.
[00:20:17]
Wahab Alshahin: Didn’t necessarily have the avionics for anything on there–
[00:20:19]
Host:Okay.
[00:20:20]
Wahab Alshahin: Or any of the peripherals, like the crew life support system.
[00:20:24]
Host:Yeah.
[00:20:24]
Wahab Alshahin: But it was a boilerplate capsule that basically weighed about the same as the crew module would when you put humans on board.
[00:20:32]
Host:Makes sense, right? You want a test that’s actually–
[00:20:33]
Wahab Alshahin: Yeah, yeah. I mean–
[00:20:33]
Host:Going to be able to pull that weight at a certain speed.
[00:20:34]
Wahab Alshahin: Yeah, you absolutely, and the crew module weighs about like 300, or 30,000 pounds, so you want to make sure that you’re, [laughs] that weight is there.
[00:20:42]
Host:Yeah, yeah. Absolutely. That’s something you don’t want to just say–
[00:20:45]
Wahab Alshahin: You just say–
[00:20:45]
Host:Oh, we’ll just assume. Yeah.
[00:20:47]
Wahab Alshahin: Right.
[00:20:47]
Host:[laughs] Awesome. I have seen that video before, and it is super cool, especially the, I don’t what, if it’s called super-slow motion, but they do have one–
[00:20:55]
Wahab Alshahin: Yep.
[00:20:55]
Host:Where it just, it fires, and you see those engines firing, and then the screen for a full second just goes like, it goes black a little bit, right.
[00:21:03]
Wahab Alshahin: Yeah.
[00:21:03]
Host:So you just see, like, it’s so bright that the camera is adjusting its exposure. And it’s like, whoa. And it goes bright, black for just a second and then shoots straight up.
[00:21:12]
Wahab Alshahin: Yeah.
[00:21:12]
Host:It’s super cool.
[00:21:13]
Wahab Alshahin: I know exactly what part you’re talking about.
[00:21:15]
Host:Yeah.
[00:21:15]
Wahab Alshahin: And next time you’re watching that slow-motion video and while they’re going through the pitch over maneuver, I’m sorry, the reorientation maneuver where they’re actually doing that flip–
[00:21:24]
Host:Yeah, yeah.
[00:21:25]
Wahab Alshahin: Put, like, ballet or classical music in your head, [laughs] and that’s kind of why I [laughter] feel like that.
[00:21:30]
Host:[inaudible] ballet.
[00:21:30]
Wahab Alshahin: It’s, yeah, it’s just this thing flying through the air, and it’s–
[00:21:34]
Host:Dun, dun.
[00:21:35]
Wahab Alshahin: Yeah. Yeah.
[00:21:35]
Host:All right, okay.
[00:21:36]
Wahab Alshahin: And that’s kind of why, every time I [inaudible], that’s what I think in my head, but that’s just me.
[00:21:40]
Host:Very cool. Awesome. Yeah, I’m definitely going to, definitely, we’ll see — do you know where on the website it is, where we can actually point some folks to to go listen to it? And what’s the test called? Maybe they can just search it.
[00:21:52]
Wahab Alshahin: Sure, that’s the easiest way. NASA videos that are on YouTube is the easiest way.
[00:21:56]
Host:Yeah.
[00:21:56]
Wahab Alshahin: It’s Pad Abort 1.
[00:21:57]
Host:Pad Abort 1.
[00:21:58]
Wahab Alshahin: Yep.
[00:21:58]
Host:Okay, everyone.
[00:21:59]
Wahab Alshahin: And it was in 2010.
[00:22:00]
Host:Okay. Pad Abort 1 back in 2010.
[00:22:02]
Wahab Alshahin: That’s right.
[00:22:03]
Host:Awesome. So what have you done since 2010 that you said there’s been some changes?
[00:22:07]
Wahab Alshahin: There’s been some minor changes to, oh, both the hardware and the software.
[00:22:12]
Host:I see.
[00:22:12]
Wahab Alshahin: But ever since I’ve started, we’re gearing up for the next portion of the testing phase, which is actually putting the Orion, some boilerplate Orion capsule, the launch abort system, on a booster — not necessarily the entire rocket — but some booster, begin an ascent on the booster, and then perform an abort from that flight mission. So doing an abort as opposed to from the pad in, while the vehicle’s moving.
[00:22:38]
Host:A rocket on a rocket.
[00:22:39]
Wahab Alshahin: A rocket on a rocket. That’s right.
[00:22:40]
Host:Cool. When’s that one scheduled for?
[00:22:42]
Wahab Alshahin: April 2019 is the current time frame.
[00:22:44]
Host:Okay.
[00:22:45]
Wahab Alshahin: Yeah.
[00:22:45]
Host:All right. Do you know what kind of rocket you’re going to be using?
[00:22:47]
Wahab Alshahin: Yeah. It’s a, it’s just a booster that’s being designed by Orbital ATK.
[00:22:51]
Host:I see.
[00:22:51]
Wahab Alshahin: Yeah.
[00:22:51]
Host:Okay.
[00:22:51]
Wahab Alshahin: It’s an abort test booster. Just a custom rocket.
[00:22:54]
Host:Custom rocket just for this. They’re very cool.
[00:22:55]
Wahab Alshahin: Yeah. Nothing that’s going to take you to space.
[00:22:58]
Host:Yeah, but just because, you know, you have to test actually [laughs] escaping–
[00:23:02]
Wahab Alshahin: Right.
[00:23:03]
Host:From a speeding rocket.
[00:23:04]
Wahab Alshahin: Right.
[00:23:04]
Host:I can understand that. That’s pretty cool.
[00:23:05]
Wahab Alshahin: Yeah. So that’s at, for me, that is the exciting flight test where I want to see this actually get used, and work, and, yeah, that’ll be cool.
[00:23:13]
Host:Yeah, that will be amazing.
[00:23:14]
Wahab Alshahin: Yeah.
[00:23:14]
Host:That’s awesome. So there’s another one too, right? Are, is there, where, you know, the, we’re talking about this in 2019. Is the launch abort system going to be part of EM-1, or EM-2, or anything like that?
[00:23:29]
Wahab Alshahin: Anytime there’s crew on board, it will absolutely be on there.
[00:23:33]
Host:Crew on board.
[00:23:33]
Wahab Alshahin: Yes, yeah.
[00:23:33]
Host:Okay.
[00:23:34]
Wahab Alshahin: So for EM-1 is currently, as of recently, not a crew mission.
[00:23:39]
Host:Okay, yeah.
[00:23:39]
Wahab Alshahin: So the launch abort system will not be used on that because we have no purpose for using it.
[00:23:43]
Host:I see.
[00:23:44]
Wahab Alshahin: But for EM-2, when the crew is on there, absolutely, yeah.
[00:23:46]
Host:Yes.
[00:23:47]
Wahab Alshahin: We will not be flying a crew without [laughs] an abort mechanism–
[00:23:49]
Host:Very cool.
[00:23:50]
Wahab Alshahin: Just because spaceflight is hard, and you can’t design for everything. You just, it’s–
[00:23:54]
Host:Yeah.
[00:23:54]
Wahab Alshahin: We have to make sure that we have — the crew safety is top priority in spaceflight.
[00:23:59]
Host:So EM-1, we keep referring to that — I try to stay away from acronyms on the show, but–
[00:24:03]
Wahab Alshahin: Sure.
[00:24:04]
Host:We’ll go back to it. It’s Exploration Mission 1, right?
[00:24:06]
Wahab Alshahin: That’s right.
[00:24:06]
Host:That’s where we’re actually going to put Orion on top of the space launch system–
[00:24:10]
Wahab Alshahin: That’s right.
[00:24:10]
Host:And test out to make sure everything’s okay. And that one actually goes to the Moon, right?
[00:24:14]
Wahab Alshahin: That’s right, yeah. It does.
[00:24:15]
Host:Yeah.
[00:24:15]
Wahab Alshahin: It’s going to circle around the Moon and come back, so–
[00:24:17]
Host:Yeah. It’s going to go really far past the Moon too when it circles around.
[00:24:20]
Wahab Alshahin: That’s right, yep.
[00:24:21]
Host:It’s going to be some good imagery.
[00:24:22]
Wahab Alshahin: Yeah, so it’s, it’ll be an exciting time for the first time we have some human-rated vehicle going out towards the Moon and coming back.
[00:24:30]
Host:Yeah, first time in a long time. That’s going to be awesome, yeah.
[00:24:33]
Wahab Alshahin: Very awesome, yes. [laughs] I agree.
[00:24:34]
Host:And EM-2 is going to be later, but we’re actually going to put a crew aboard, and they’re going to do sort of the same thing, right?
[00:24:40]
Wahab Alshahin: That’s right.
[00:24:40]
Host:They’re going to go around the Moon, and–
[00:24:41]
Wahab Alshahin: Yeah.
[00:24:42]
Host:Yeah. That’ll be a great mission to do. So just Orion in general, obviously, you know, you’re, when we talk about this, the reason that I’m excited about this episode, just besides learning about this really cool technology — a rocket on a rocket just sounds so cool — but the idea that each part of the rocket has so much intricate detail that needs to be paid attention to.
[00:25:03]
Wahab Alshahin: Yeah.
[00:25:03]
Host:You know, you’re talking about the launch abort system, Orion service module. All these different parts have to come together just right to make the whole thing. So, you know, what are some of the challenges for Orion for the capsule but also the whole system, the whole idea of space launch system and going farther and deeper into space than ever before?
[00:25:27]
Wahab Alshahin: Yeah. You kind of, as you were listening to all those things, in my head, I’m thinking about, who are our partners through, in the design process for building this, some of this hardware? And that’s probably the most challenging thing. Like, the service modules being built by the European Space Agency. The crew modules being built here, but Lockheed has, is the primary contractor. The abort motor engines are being built by Orbital ATK. So there’s all of these people that are spread out all across the globe, really–
[00:25:55]
Host:Yeah, yeah.
[00:25:56]
Wahab Alshahin: That are helping to build portions of the space launch system. And even if they are here in the United States, they’re spread across the United States. So–
[00:26:04]
Host:Right.
[00:26:05]
Wahab Alshahin: That’s one of the biggest challenges, and I deal with this every single day is dealing with and working with people remotely and trying to break those barriers to, you know, having efficient dialogue on a day-to-day basis. So–
[00:26:16]
Host:Because you’re all–
[00:26:16]
Wahab Alshahin: Yeah.
[00:26:16]
Host:Designing stuff for this one idea, right–
[00:26:19]
Wahab Alshahin: Yeah.
[00:26:20]
Host:For a rocket that’s going to go into deep space, so you’ve got to make sure you’re talking and got to make sure everyone is on board for what’s happening.
[00:26:25]
Wahab Alshahin: Absolutely, yeah.
[00:26:26]
Host:Yeah. Makes a lot of sense. Awesome. Wahab, this was such a cool topic. Is there anything else about launch abort system that I may be missing or something that we go dive deeper into?
[00:26:36]
Wahab Alshahin: We, so I think we touched upon some of the interesting aspects of it technically.
[00:26:42]
Host:Okay.
[00:26:43]
Wahab Alshahin: I guess I can leave you with one little story about, so it’s historical testing–
[00:26:48]
Host:Okay.
[00:26:48]
Wahab Alshahin: Just because I find this one fascinating.
[00:26:50]
Host:Oh, yeah.
[00:26:52]
Wahab Alshahin: So for the, we’re doing our ascent abort test, like I said, in 2019.
[00:26:56]
Host:Right.
[00:26:56]
Wahab Alshahin: We also did ascent abort tests in, for the Apollo era missions, so this test is going to be very similar to that, so we designed some custom booster in the 1960’s to test the launch abort system.
[00:27:08]
Host:Okay.
[00:27:08]
Wahab Alshahin: So when we were actually going out there for that test, it was I think 1966, the booster fired. So now, you’re ascending through the atmosphere. And at some flight condition, the launch abort motor was going to be triggered to test the entire hardware. What actually happened was that something happened with the test booster during the design portion or the manufacturing portion, and the rate gyros were instrumented incorrectly — upside down or something — so the booster, as soon as it launched, started spinning, and it started spinning faster, and faster, and faster.
[00:27:43]
Host:Whoa.
[00:27:43]
Wahab Alshahin: So instead of triggering an abort at some designated altitude, we actually had a real abort on an abort test [laughs] because the launch vehicle actually ended up breaking apart.
[00:27:53]
Host:How about that?
[00:27:53]
Wahab Alshahin: Yeah, so that is the best test that you can actually have for this flight system.
[00:27:58]
Host:So it worked, right?
[00:27:59]
Wahab Alshahin: It absolutely worked, yeah.
[00:28:00]
Host:Because it did its job. It–
[00:28:01]
Wahab Alshahin: That’s right.
[00:28:01]
Host:The rocket did something crazy–
[00:28:03]
Wahab Alshahin: Exactly.
[00:28:04]
Host:And it did its job. That’s fantastic.
[00:28:06]
Wahab Alshahin: Yes, that’s like another example of that was not the intent of that test. The intent was not to actually replicate a launch vehicle failure, but that’s what we got. And the system performed admirably.
[00:28:15]
Host:Wow.
[00:28:16]
Wahab Alshahin: Yeah.
[00:28:16]
Host:I love that story. [laughs]
[00:28:17]
Wahab Alshahin: It’s just a, yeah, it’s, I hope that that doesn’t happen for ascent abort test two, but the one that we had was–
[00:28:24]
Host:Hey, well, if you’re over engineering it to deal with, you know, any situation, you know, you should be good to go.
[00:28:29]
Wahab Alshahin: Yeah.
[00:28:29]
Host:I think you’ll be fine.
[00:28:31]
Wahab Alshahin: And that one actually is, there’s a great video of that as well on YouTube. That’s the Little Joe booster Apollo abort test.
[00:28:39]
Host:Little Joe, all right. I’m going to mention that again once we — Little Joe booster, Apollo.
[00:28:44]
Wahab Alshahin: Yeah.
[00:28:44]
Host:That’s amazing. So cool. All right, Wahab, this was so cool. Thank you so much for coming on the show. For our listeners, if you want to stay tuned until after the music, we’re going to tell you, we’ll reference some of the videos that Wahab shared with us today so you can go watch them, a little bit more on how you can ask questions and be a part of this conversation. So Wahab, thanks again for coming on the show. It’s been an absolute pleasure.
[00:29:08]
Wahab Alshahin: My pleasure as well.
[00:29:10]
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[00:29:35]
Host:Hey, thanks for sticking around. So today, we talked about Wahab Alshahin about launch abort systems — literally rockets on top of rockets. Super cool. If you want to know the latest updates of what’s going on in that world, Wahab actually works on the Orion program. So if you go to NASA.gov/Orion, you can see all the latest updates there. They’re also very active on social media, and we like to cover it on several accounts. You can go to the NASA Johnson Space Center account or the Orion accounts on Facebook, Twitter, and Instagram. Don’t worry, they’re all verified, so they’re very easy to find. Just use the hashtag, #askNASA, or hashtag, #HWHAP, H-W-H-A-P, on your favorite platform and submit an idea, or maybe you have a question about launch abort systems or Orion, and we’ll make sure to address it on one of the later podcasts here. This podcast was recorded on July 12th, 2017 thanks to Alex Perryman and John Stoll. And thanks again to Mr. Wahab Alshahin for coming on the show. We’ll be back next week.