Suggested Searches

The Heroes Behind the Heroes: Part 3

Season 1Episode 90May 3, 2019

In part three of a special series, the heroes take on another technical challenge to rescue the Apollo 11 mission control tapes for posterity and for academic research. HWHAP Episode 90.

Heroes Behind the Heroes Part 3

Heroes Behind the Heroes Part 3

“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 90 is part three of a special series, and picks up as the heroes take on another technical challenge to rescue the Apollo 11 mission control tapes for posterity and for academic research.

If you’re interested in hearing more of this historic audio from the Apollo 11 Mission Control Center check out the Explore Apollo website. For more of our Apollo Podcasts, including part one of this series, check out the “Houston We Have a Podcast: Apollo 50th Anniversary” webpage!

Houston, we have a podcast

Transcript

Pat Ryan (Host): Houston, we have a podcast. Welcome to the official podcast of the NASA Johnson Space Center. Episode 90, “The Heroes Behind the Heroes,” Part 3. I’m Pat Ryan. Looking forward to bringing you the next chapter in this story. So far we’ve met Dr. John Hansen. And learned about the goals of his academic research to develop machines that can understand human speech. And about how he discovered the audio recordings from mission control Houston during the Apollo 11 mission to the moon. And wanted to use them to explore the use of language by large groups of people working together to solve problems. More than just asking your phone how to cook a brisket. Well, we found him and his team as they struggled to find new hardware to outfit a 50-year-old audio tape player that they needed so that they could listen in on the flight control team in 1969. When we left our heroes, they had pulled a rabbit out of a hat and found an audio playback head that could read 30 channels at once. Just the thing they needed. And if you’ve been following this story, you can guess that this means they’re about to encounter the next roadblock. And you’d be right. That’s where we start part three of “The Heroes Behind the Heroes.” Here we go.

[ Music ]

The Roman statesman Seneca said “Luck is a matter of preparation meeting opportunity.” And that would explain why good luck has a way of coming along right when you need it. If you’re a person who keeps working to solve your problems. John Hansen got lucky when he found the tapes of the Apollo 11 mission control team. The raw material for his academic research. The University of Texas at Dallas professor is trying to develop speech recognition technology that can work with large groups of people who are talking to one another while trying to solve problems. So we can learn more about how the successful ones work. He was a bit less lucky to find that the audio existed in analog form on reel-to-reel tapes. And could only be played back on a 50-year-old machine that wasn’t equipped to play all 30 tracks of audio on those tapes at one time. Which is what he needed to have happen so that he could digitize the tapes and maintain the relationship in time among the separate conversations on those tapes. But as luck would also have it, he found some help in running down a piece of hardware that would do the trick. A new 30-track playback head that had been sitting on a shelf in a warehouse in Belgium. He was hoping that his luck hadn’t run out.

John Hansen: In the process of kind of getting that built, we still needed to have kind of a full hardware solution on how to digitize this. So that meant finding a pre-amplification system for each of the channels. And then a digitizing process that would allow us to keep up with each of the data rates for all 30 channels at the same time.

Host: Let me try to simplify it for me.

John Hansen: Okay.

Host: You’re talking about finding a way so that, when you could, if you had a 30-track playback head. That those 30 different channels, the audio from each of them would be, maintain their integrity. But also be recorded digitally in some way that you would still be able to keep them synchronized with one another to do your ultimate task. Which was to be able to do this research.

John Hansen: So the best analogy I can give is imagine that you are trying to capture the audio from a symphony.

[ Music ]

And you have 30 instruments on stage. And each one of them has a microphone. And you’re wanting, you’re going to take the audio from each of those microphones. And you’re going to blend them together. So imagine now that someone has done that 50 years ago onto the tape. Now you need to go back and pull each of those off individually. But you want to make sure that they’re all synchronized. So this way you can look across all of those audio channels as a collective group. And so to do that means that you’ve got to have a digitizing process that can keep up. That when it digitizes one channel, it doesn’t fall behind on any of the other channels. So that means you have to have pretty good analog to digital conversion. Fortunately, we have a company down the street from our university called Texas Instruments who is the leader of analog to digital conversion and invented the integrated circuit. Jack Kilby’s work. So we were pretty lucky that, you know, obviously these types of technologies exist today.

Host: In this case, though, technology was only part of the solution. Hansen needed more human help to bend the technology to his will. He found some of that human help close at hand in one of his own students.

Tuan Nguyen: My name is Tuan Nguyen. I study biomedical engineering at UT Dallas. And I graduated in 2016 of August.

Host: Biomedical engineer. What does that mean for somebody who’s not smart like me?

Tuan Nguyen: Pretty much it deals with, I mean, it’s very broad. It can be dealing with other things, but mostly a lot of medical devices. You know, anything from the hospital beds to the EKGs, you know, that measures the heart rates and stuff. I mean, it’s very broad. I mean, you can do a lot of things with it. But I’m not really specifically specialized in any area. So it’s just a degree for me.

Host: If you’re there majoring in biomedical engineering, how did you get involved with John Hansen and his work?

Tuan Nguyen: Okay, so I was doing my senior project at the time. And Dr. Hansen was pretty much my project mentor. He managed about eight groups, senior project at the time. So, I mean, I didn’t really get to hear about all this project that he’s been proposing until my last day at the expo. That my last, second semester. So, I mean, you know, he had eight teams. So I was kind of shocked and surprised that he looked at me. You know, he was telling, oh, yeah we have this thing going on with NASA. And, you know, it’s Apollo 11 project and stuff like that. He looked at me, Tuan, would you want it be a part of it? You know, I was surprised. Like I don’t even know, I mean, you know, you have eight teams. I mean, that’s a lot of, you know, students under him. But I guess he saw something in me that I really didn’t see in me so.

Host: Explain to me what the project was. How did he present it to you? What was he trying to do?

Tuan Nguyen: So he, I mean, he say something about historical events, that we’re trying to preserve these Apollo 11 tapes. Because, I mean, it’s been locked up in a vault for about, over 40-some years. So he afraid that the tape’s going to get decay. And, you know, forever be gone with the historic event, you know, the first man on the moon. So, I mean, what he’s trying to do. So I’m like the last guy that he really recruited to be sent down to NASA and kind of get, you know, get all these tapes done for him. And for NASA. I mean, you know, it’s really for the public interest. It wouldn’t be for engineers or researchers, yeah.

Host: So he did have a specific task in mind when he recruited you?

Tuan Nguyen: Yes, sir. Yes, sir. So I was the fifth, last member pretty much to the team. And then we have a first meeting as well. And he was sending me all these e-mails regarding to the project. It’s kind of overwhelming, I mean, you know. I really don’t understand what he’s trying to do. I mean, I did get the overall point of what he’s trying to do. But for my specific role, I really don’t know. It was pretty vague at that time; right? Until the first meeting. Then, because I think the skills that I build up in this senior project, it helped me in completing this task pretty smoothly.

Host: What skills were you bringing to the group that he needed you to use?

Tuan Nguyen: Okay, so pretty much, yes, sir. So I guess my work ethic is one thing. And I deal with a lot of SolidWorks. Because I was responsible for building electromechanical models of the middle ear. For our project we had two different, I’m going to say sections of the project. It’s like a project within a project. So I was responsible for, solely on developing an electromechanical model of the middle ear. And, you know, kind of like an education tools for K to 12. And to kind of representing the middle ear bones that we have.

Host: And then this was for some other project or Hansen’s project?

Tuan Nguyen: That’s the senior project that he was mentoring us. With Abhijeet, he was also assisting mentor as well. Yeah, but that project is, so I developed the skill of using SolidWork, which is like an AutoCAD. That I would draw up stuff and kind of print it or cut it based on the dimensions. All the exact dimensions and stuff. And I think that’s what he needed as well. Because that’s what I’ve been doing, trying to build, was it, a front plate. A front face plate can actually implement to the SoundScriber.

SoundScriber

Host: SoundScriber is the big tape playback machine from the 1960s. The one that could only play back one track of audio at a time from the 30-track recording of the Apollo 11 control team. Nguyen was joining the project when Hansen had a new 30-track playback head in hand. But still needed help to get it integrated into a newly designed digitizing system.

Tuan Nguyen: Well, that project is pretty much, there’s no training. There’s no training whatsoever. So when the first time that the meeting was holding place at the, in one of these cochlear implant rooms. This is, we’re trying to figure out the problems. How to pretty much fit all the connectors that the 30-track head was built. Because SoundScriber, you know, you have to get through in the back to really connect all the wires. So that’s a little problem that we have and issues. That the challenging part is that this little hole is small. It’s too small for the connectors to come through. So we had to find a way how to convert that into smaller connecters that can go into the back of the SoundScriber. And kind of, I can go get into it a little bit more details on the construction part of it. But for, yeah, but for now it just pretty much that’s what we trying to issue, that’s the first issue.

Host: So at the time that you came into the project, Hansen was already aware that the tapes would have to be digitized. And they’d have to build some hardware in order to simplify and speed up that process. And I guess you helped him figure out how to do that?

Tuan Nguyen: Yes, sir. So everything was, I mean, it’s all options. So we look at different options on mixers and pretty much storage. So how much storage we need to what the first— the main part of the goal is to get all the Apollo 11. And that is it. And so we need all this storage. And we kind of calculate, figured out how much storage we need. And also the best mixers that can handle all 30 tracks. So we did a lot of plannings and organizing. And also have a triage down here that also did–

Host: I’m sorry, you have a what here?

Tuan Nguyen: Triage. So pretty much what, how can I organize data? And what else can I work on besides just digitizing the tape? So I would pretty much listen to all the Apollo 11. The whole missions. And kind of jot down notes and what happened in this part. What they do in this part. From take off, to landing, to splash down pretty much.

Host: When you showed up here and, as you started to talk about looking at the SoundScriber and figuring out the mechanical aspect of how to make the changes. How did that present to you as somebody who, with experience in school building these mechanical devices? What did you see as the really the main problems you were faced with in trying to take this ancient elephant of a machine to do what you wanted it to do today?

Tuan Nguyen: The first week, I would say, down here at NASA was very, very challenging. It’s one of the stressful week for me. And prior to me coming out here, it takes me about two months to really get all the equipment ordered and kind of test it. We, I actually start building the DB-25 connector from scratch. So all the wires that actually going from the DB-25, which is connected to the mixer. You know, and connect all the way up to the 30-track read head. And everything was built and constructed from scratch.

Host: And, I’m sorry, explain what a DB-25 connector is.

Tuan Nguyen: A DB-25 pretty much is, connector, is where it holds per channels. So each DB I can get about eight channels out of it; right? And then so I need about three DB-25 connectors. Which would hold each of ten. So it’s 30 track. So it would hold all 30 track, ten each on the DB-25 connectors.

Host: And this is the wiring then that’s–

Tuan Nguyen: Yes.

Host: Connecting the playback head to–

Tuan Nguyen: Yes.

Host: The recording device.

Tuan Nguyen: Yes.

Host: Okay, so you had to design that?

Tuan Nguyen: Yes. We had to build that. So I actually had to go order those DB-25. You know, just to have the connectors itself. It kind solder over 200 wires or more. It’s very tedious. So I had to do one wire at a time. Soldering and kind like of convert the big connectors of the heads, kind of convert down to smaller connectors. Kind of like, so the wires everywhere. So, I mean, it’s just criss-crossing everything. And, I mean, we have pictures of that as well. But, yeah, it’s a process. It’s a two-month process.

Host: And that’s, you’re saying just to wire in this piece of hardware that had been developed and get yourself ready to start the–

Tuan Nguyen: Yeah. So everything have to be ready on campus before. Because, you know, I can only test about, if the signal’s going in right. Or how the sound is. You know, because we have no way of testing the real heads until get down here and implement it into the SoundScriber. But the whole process from day one, drawing up the circuits. How the wiring’s going to be. What to get. And pretty much make it neat and nice before we come down here and plug it in.

Host: Just plug it in. Right. If only it were that simple.

John Hansen: When we were done, we took the full system, drove down here. My student and myself. And we went into SoundScriber. And I was really hopeful that Greg was going to have a team of NASA engineers standing next to me and going to install this and–

Host: Thank you, sir, we’ll be, take it from here.

John Hansen: Yeah. And that was, I was hopeful about that. But that didn’t happen. I have to say, without Greg we just would not have been able to do any of this. This is really just, you know, his support was really helpful. But for this, you know, I turned to my student. I said, well, look, I worked as a technician. I put myself through college, you know, soldering and building stuff. I said I think I can do it. Because my student said, Dr. Hansen, I don’t think I can do this. I said, no, let me figure this out. So I was on my back underneath the SoundScriber system and rewiring it myself. And he was passing me pliers. Screwdrivers. And we were doing rewiring. And we had to be careful because SoundScriber is a pretty big playback system. Half of it has the motors to actually move the tapes. And then the adjustments for the read heads. But the other half actually is an amplification system that you could hear the audio. And that amplification system is all based on tubes. And the voltage in some of that space is 480 volts and some crazy amount. So you don’t want to be putting your bare hands up in that space. That’s kind of dangerous. So my student was, he had to stay outside. Or not out, but just handing me stuff. And it was a big challenge. I took a lot of pictures because I wanted to document it. I kept telling my student, if we mess this up, we’re going to be in real trouble. Because we would have destroyed the only playback system that actually exists. And, I have to say, NASA, I don’t know why they allowed me to do this. Maybe they just didn’t know. But they let me do it. And it, we were able to get everything installed. We actually built a patch panel for the front of SoundScriber. Because the system in the past had one wire coming off that was time code. And a second wire that would actually have the analog unit or the audio that was coming that particular channel.

Host: Off of the one channel that was being played back.

John Hansen: Off the one channel and, you know, Greg was actually very helpful. Because you need a lot of amplification for that. The audio signal coming off that one channel is really not high enough to have it go through an analog to digital conversion process. So you’d need a lot of gain on this. And so this was one of the things we had to spend some time on, trying to find a good pre-amplification system that would amplify all the channels at the same rate.

Host: Did you find something that existed?

John Hansen: Yes, we did. And fortunate, we were really lucky in that regard. Because, if you look at the music industry, you know, there’s lots and lots of audio recording systems that assume that you have multiple channels. And so these resources, Tascam and Fostex, are the two manufacturers. There’s lots of equipment out there. And so getting the pre-amp set up was actually not too difficult for us. We were happy with that.

Host: The Greg that Hansen’s referring to there is Greg Wiseman, an audio engineer here at NASA’s Johnson Space Center. He had gotten the tapes of the Apollo-era mission control teams delivered from the National Archives back to Houston. And was on hand ready to help.

Greg Wiseman

Greg Wiseman: So Hansen showed up with his new recording rig. And this new 30-channel head. And we went in, and we began trying to install the new equipment. The first step was to remove the old head and affix this new head to the mounting plate. We also had to figure out how to manage all of this new wiring. The design of the SoundScriber was to accommodate for a couple of wires for a couple of channels. And now we had 30 channels. And so we had this thick bundle of wires coming off the head. And not a lot of real estate to figure out how to route it so that it wouldn’t be in the way. The cool thing is that Hansen and his team had already done a lot of homework beforehand. So they had taken measurements of the SoundScriber cabinet. And built up an input panel that we could mount directly to the front of the machine. This input panel had four D-sub multi-channel connectors. So the idea was that we could take this snake off of the head and route it to the back of these connectors and solder it onto the connectors. So we found an area. We, what we did is we removed one of the audio connectors, the old audio connectors that was built into the SoundScriber. And once we punched that out, it left a hole from the front deck of the tape deck that we could take the snake and work it through that hole into the guts of the SoundScriber cabinet. And then come around the back and solder it onto those D-sub connectors. So that part worked great. It looked great.

The next step was to make sure that the head was properly aligned to the tape. Now, the only way to really do that is we, you have to load up a tape that has some audio on it. You roll the tape. And then you make adjustments to the head so that you’re hearing back the audio that you expect on the right channel. The head that we, the new head is still mounted on this same little adjustable block that you turn a little crank. And it moves the head up and down the width of the tape. Now, we only have to, once we get it aligned, we would lock that down. We never, we would hope to never have to use that again. We just want to line it up this one time. So we start trying to figure out how to do that. The problem is that the tapes that we have, it’s intermittent com-audio. So there’s not constant audio across all of the channels all of the time. Ideally, if you’re going to calibrate a new head that you’re putting on a tape machine, you’d have a calibration tape. A calibration tape’s going to have some kind of reference tone on every channel of tape. So that, once you make your alignment, so that you can make your alignment. But we didn’t have that. I had researched some calibration tape vendors months before. And couldn’t find anybody that had a one-inch 30-track calibration tape. So that was a problem. But the one thing that we did have was IRIG time code. Time code was recorded on channel one for every tape that we have. And the time code is, it’s really cool. You can run that into an IRIG decoder, and it will give you precise GMT timing for the tape. But audibly it sounds like a constant square wave with the same exact level. So we figured that we could use that as a reference. So the idea would be that we would move the head until it, we started hearing IRIG come out of channel one. And then we would kind of move the head back and forth until we, the audio level was the strongest. So once it was perfectly centered, I mean, once the level coming off channel one was the loudest that we could get it. Then we assumed that it was perfectly centered over channel one. And we hoped that the spacing on the head matched the spacing of the tracks across the tapes. So that, if channel one was aligned, then channel 30 would also be aligned. So once we did that and we got channel one aligned and we were hearing good strong IRIG time code coming off channel one. We began playing more tape and started listening to the other channels to see how they sounded. Right away we noticed that there was a lot of crosstalk or there was some crosstalk between channels. But we weren’t completely sure if this crosstalk was a problem with the new head. Or if it was a part of the original recording. Trying to understand what you’re hearing and troubleshooting that without a baseline understanding of what you should be hearing made it difficult.

John Hansen: So we put everything together in the SoundScriber. We started rolling tape. And probably took maybe three or four days of adjustments. Because, you know, when you adjust the head, it’s still mounted actually on these little mechanical flywheels that you would rotate. And the hope is that we would set it to one spot and then lock it. Never change it. Because then it would actually, hopefully, be in the sweet spot across all 30 tracks.

Host: Where the tracks would have been when they ran across the record head.

30 Track Head

John Hansen: That’s right.

Host: Fifty years ago.

John Hansen: That’s right. So we made those adjustments. There was a little bit of reengineering that we had to do here. We found out that, in order to kind of minimize all these cables for the read head, we actually routed all of the wiring through a harness to the back of SoundScriber. To route it inside the unit. And then we set up a patch panel on the outside with three different connectors of 25 pins each. Where we could kind of get eight to nine or actually, sorry, ten channels off of each connector. And that allowed us to actually make things cleaner so you wouldn’t have all these wires running all over the place. But what we didn’t realize was that there was some grounding loops that took place on this. So we had to go back and add some additional grounding capabilities on this in order to get the digitizing process done well. But after about three or four days, we were able to figure it out. My student, and I think Greg was also involved in trying to help make sure that that took place. But that was yet another engineering challenge to work out.

Host: Wait, let me stop there for a second. This part of the story is much more fun and exciting when Tuan Nguyen and Greg Wiseman tell it.

[ Music ]

Tuan Nguyen: So let’s start with the first day I was here, so.

Host: I got a feeling it’s going to be different than the other days.

Tuan Nguyen: Yeah. The first day, so me and Dr. Hansen came down and we, you know, we hook in our system to the SoundScriber. And we have a little bit of issues with the channels bleeding. Kind of cross-talking from IRIG all the way down to I think eight or nine channels. Which is not a good quality of audio, right? It was bleeding. So it took about a week to get it resolved. I remember one time I was calling Dr. Hansen from here. Syaing Dallas we have a problem. You know, despite of Houston we have a solution. Dallas, we have a problem. So, I mean, it was a stressful week; right? So trying to figure out what is the head, is kind of myst—the head. So, I mean, we try to figure out what’s wrong with it.

Greg Wiseman: So we started making some recordings. But our initial recordings, when we started monitoring it, we noticed that there was a lot of crosstalk initially. There was a lot of, something didn’t sound right. And there was a lot of noise. So that stopped us right there. And so Tuan and Dr. Hansen and myself, and we got on a teleconference with John French. Who was the guy that had provided the head. And so we started looking at the wiring diagram for the head. And trying to make sure that there wasn’t some mistake in the way that they had wired it up to those connectors.

Tuan Nguyen: For that whole week, the first week, I mean, it was just trying to figure out how, why this bleeding is taking place. And we was, we did some ground work to it, some ground wires. And kind of, I think the last solution that we have, I mean, we tried a lot of solutions on testing how to resolve this problem. The last thing that we actually did was I flipped two wires and it works. The whole week, just two wires.

Host: You mean switched them?

Tuan Nguyen: Yeah. From ground wire to the negative wires, and it worked. That whole first week just, that come down to two wires.

Greg Wiseman: And so he made one little jumper change, and everything cleared up. All the, a lot of the crosstalk went away. And we were able to start rolling. And that was, we were kind of dead in the water until we were able to fix that. And we were a little bit disheartened at that point because we didn’t know what the problem was. And, but it was an easy fix and–

Host: It turned out to be.

Greg Wiseman: It turned out to be an easy fix. And, but as soon as that happened, then we started rolling. And everything sounded great, and then that was it.

Host: Okay. Clear playback has been achieved. And Nguyen finished setting up the hardware that would capture the signals from the 30 tracks of audio on the old tapes and route them through to a recorder. Which is, I guess is just a computer; right? Like a laptop computer.

Tuan Nguyen: Yeah, it’s a laptop with a mixers involved. So the mixer’s pretty much, that’s the one that’s extracting the data from the tapes, from the SoundScriber. So the 30-track head is pretty much reading the tapes. And then we also have the storage on hand from the laptop where we extract the data backup to down. And then furthermore, that’s when I process the data.

Host: Let’s talk about some numbers. There are 30 different tracks of material on this tape. And I know that one of them was IRIG, and we don’t really care about that.

Tuan Nguyen: Right.

Host: But on a, what is it? A 14 or 15 hour.

Tuan Nguyen: And a half, sometimes 16 hours.

Host: How much material in computer size, a number that people understand. How much material is that on one tape?

Tuan Nguyen: We talking about just one tape?

Host: Yeah.

Tuan Nguyen: One tape, probably about, you know, I don’t remember exact numbers but.

Host: Gigabytes? Terabytes?

Tuan Nguyen: Gigabytes.

Host: Gigabytes.

Tuan Nguyen: It’d have hundreds of gigabytes.

Host: Hundreds of gigabytes on just one tape.

Tuan Nguyen: Yes.

Host: And you got how many tapes?

Tuan Nguyen: We have about 30 tapes, correct, 30 tapes.

Host: So.

Tuan Nguyen: So we need about terabytes, we talking about terabytes here.

Host: Ultimately, that you’re recording onto a laptop computer. And then all floating onto some removable storage.

Tuan Nguyen: Yes. So from there on, I carry it onto another laptop. That’s when I do my, all the processing work on the data.

Host: Okay, talk about that while we’re there, processing. I can understand, and I’m not an engineer. I’m not even, I mean, I know how to use this end of the microphone, not the other end. I understand that you play back the tapes, and you’ve got this data that comes off as audio. People talking. Convert it into files on your laptop computer. But then what do you have to do to that? You said you had to process it. What do have you to do to that? What are you trying to turn it into?

Tuan Nguyen: We’re not really turning it into, what our process is, I kind of break down those 14 hour and a half or probably 15, 16. Depends on the tapes. Into 30-minute chuck chunks. That way it will be easier to research and study on it, on how the communication within the flight mission control centers really works. Like all this criss-cross communications, interaction between all the flight controllers and engineers. All the back rooms at the time. So 30 minute would actually be ideal for all the researchers that’s doing, you know, trying to develop all these techniques, speech techniques. They’re kind of like using, I mean, I wasn’t involved, and I tell you later. But that’s pretty much what I was doing. Just break it up in chunks, 30-minute chunks. It’s easier to do research on.

Host: And that’s the research that Hansen, his academic research that he’s originally interested in this. The reason it got him interested.

Tuan Nguyen: Yes, his PhD student’s pretty much working on the development speech techniques.

Host: Okay, you got a 14.5 or 15 or 16 hour long tape. And it’s your job to play it back and record it. Play back the tape and record it on the computer. Walk me through what it’s like to, you know, on a day when you had come to work at the Johnson Space Center and have to, and play back, you know, one tape and then another and another. What was any of those days like?

Tuan Nguyen: My daily work here at NASA, I mean, at the studio. I would come in. I would run the tapes. And I would let it run for maybe 14.5 hours. That’s when I stop it, when the tape actually stopped. And I would stop, and I would extract the data. So I was spend about 55, about 50 to 55 hours a week trying to get the tapes, process the tapes. Kind of listen to the tapes. Write down notes. It was like a librarian type of, you know, storage info. And a lot of other things as well. From writing down the time code when would this play. Pretty much the date, the time, and everything had to be details, I mean, that’s involved with the tapes. It had to be jot down somewhere in my notebook.

Host: If a tape runs for 14 hours or more, I’m guessing you’re not coming in in the morning and starting it and sitting there waiting until it ends. That would be an awful long day.

Tuan Nguyen: Well, at first we did talk about how we handle the tape running. So we trying to do maybe seven at a time, seven hours at a time. And then we’ll be like two sections, seven hour one day. And seven hour the next day. But, no, we decided we’re going to do one tape per day. And I would, sometimes I would run it around five o’clock in the afternoon. And then I would come back in the morning, and it will be almost about one hour, half an hour later. And then I can stop a tape. That’s when I would extract the data down to the, I let it run overnight pretty much. So my daily work was pretty much come in the morning. Stop the tape. Extract the tape down to the storage. Then bring it down to a different laptop. That’s when I start process the data and break it into 30-minute chunks. And then kind of like have two, three backup. One for NASA. One for UTD. So we want NASA to have a copy as well. So I was like transferring data to data for storage to storage. So it pretty much, it take up all day. And then I have to listen to Apollo 11, each chunks of the audio. And all the channels that was available there. It was 30 channels. Besides the IRIG, which we, you know, is time code.

Host: Right. Which nobody with our kind of ears cares about. You solved your problem of the bleed over there at the very beginning. But what about after that? Did the mechanical part of this playback, did it all work pretty smoothly?

Tuan Nguyen: Yes, everything worked smoothly except the two wire was not in the right place. Yeah, but everything mechanically-wise, everything was smoothly running.

Host: That strikes me as kind of surprising. Something that complicated and, you know, and brand new, those kind of things generally have problems that you have to solve.

Tuan Nguyen: Well, yeah, I mean, the machine, the SoundScriber is pretty old, date 1960s.

Host: Well, all the more reason why it might have problems.

Tuan Nguyen: Yeah, but it was, you know, Greg, one of the guys that was working to refine it. And I guess it works well. It runs really well. I mean, it’s still running now, I think, yeah.

Host: Okay. So you guys figured out how to do this. And you execute it. How long did it take? We’re talking 30 something tapes. It was all of Apollo 11 and some portions of Apollo 13, right?

Apollo Tapes

Tuan Nguyen: Yes, it was actually Apollo 1, Gemini 8, some Apollo 13, and the rest Apollo 11. I was able to be done in four months.

Host: Four months to just to digitize all these tapes.

Tuan Nguyen: Digitize and process. And, yeah, kind of like bookkeeping as well.

Host: Is that kind of what were you expecting?

Tuan Nguyen: Well, no. I didn’t expect that I had to put in so much effort in it. But until down there I was really into what I was doing. And time just fly. So I was very enjoy doing it. And, you know, I had a good time here. All the folks is really nice folks. So it kind of help me, you know, not be too bored. Or to, you know, be stressed out too much. If I need help, I got all the support down here as well.

John Hansen: I think in the end we digitized roughly in the neighborhood of about 60 to 80 tapes. Somewhere in that time frame. So we’ve got, you know, at least another 120 to 150 tapes that we can go and digitize, if we had the resources. Part of my mind, or in my mind I still think Greg probably doesn’t want to see us here anymore. But I would love to actually go through and just keep doing this. I think it would be a cool project for undergraduate students that have interest in this to kind of—to, you know, participate in a digitizing process like that.

Host: And it would increase the raw data that you would have for your original study goal.

John Hansen: Yeah, yeah. So, you know, you think of this as kind of like there are two phases here. One was to kind of build a solution that would allow us to digitize it. The second part was actually digitizing the audio and then organizing it in a way where the naming convention could allow you to search through the audio blocks in some organized way.

Host: To start to put the different conversations that occurred simultaneously together, which–

John Hansen: Yeah.

Host: You had talked about. And before we go there. After all the work that you had put in to go ahead and figure out how to rescue these tapes. How to be able to play them back so that you could get all the material. The actual execution of that plan worked without any real problem.

John Hansen: Okay, well. Yeah, you said without any real problem. [laughter] Well, but I will say, you know, maybe we try to follow NASA’s, you know, either mindset or mantra. Which is, you know, whatever the, if there’s a problem, how do we solve it? How do we move forward with it? So we always took a positive attitude. Students that I had involved with this, there were undergraduate students. There were graduate Ph.D. students. I had staff members. Abhijeet Sangwan was one of my postdoc staff researchers that was instrumental throughout the whole project here. Tuan Nguyen was one of our undergrad students that helped on the digitizing process. Many, many different types of students that were involved with this. Everyone always took a positive attitude. And I just kept reminding people what, you know, this is something that, what you’re doing is work, but what the outcome will be preservation of something that will live on for a very, very long time. And it’s something that we think would help STEM. And would help, hopefully, NASA. And people understand that, you know, when NASA and when the United States committed to going to the moon, John F. Kennedy said we’re going to get there. NASA didn’t have all the solutions when John Kennedy said we’re going to get there. And so to me this was a time in our country where, you know, we set a goal. And we may not have had all the answers at that instant when we set the goal. But people worked collaboratively together to ensure that they’re going to achieve that. So this was something that we tried to inspire the students that were all involved with this with that mindset.

Retro: FAO, Retro, my loop

FAO: Go ahead.

Retro: Hey, we’re going to need to get together on this stowage stuff. Find out how much rocks and all that jazz they got—

Apollo 1 MOCR

SPAN: Flight, SPAN

Flight Director: Hey, Arn. Has anybody written up what they think the water in the suit business? I assume we’re gonna have a couple questions.

Voice 1: Rog. Since we don’t Comm Call loop, would you please relay this message to Voice Control for me?

Voice 2: How about writing it down on a piece of paper.

Voice 1: Shippin’ it up to you?

Voice 2: Yeah.

Voice 3: That’s why the only reason I think he could do it. Because ordinarily on the ground Buzz could not at maximum effort get his heart up that high.

Voice 4: Never, I’ve never seen it above 150.

Voice 3: Yeah, I don’t think, that’s what I was saying. So it’s undoubtedly, they–

[ Music ]

Host: Did you get any insights into what it takes to land? What it took to land on the moon?

Greg Wiseman: Yeah, I think so. One of the things that sort of stood out for me is how similar these recordings sound to the loop audio that I can listen to now of the folks supporting space station. It’s the same calm, cool, collected professionalism. All of these people working in a very, in a highly coordinated way on these complicated engineering problems. And, you know, sometimes even with people’s lives on the line. And they always sound like it’s just business as usual. It’s obviously a high stress environment. But they’re always focused and nothing every really seems to rattle them. So it’s impressive I think. And I think that listening to these recordings, you hear that. And you hear that then. So I think they obviously must have sort of laid the ground work for that way of working back in the early years of manned space flight. And I think what I like best about the release of this audio is that this is the rest of the story of humans landing on the moon. Everyone on the planet knows about the moon landing. It’s one of the most important engineering accomplishments of mankind. And everyone has heard the audio of Neil Armstrong saying, “One small step.” But very few people have heard the audio from the rest of the team from mission control. And these people were instrumental on the success of that mission. Yes, Neil was the man on the moon. But there were a lot of people on the ground who made that possible. And they are very much a part of that history. So this is a historical treasure chest of audio that allows us to hear the rest of that story. The story of man landing on the moon.

BTU: Surgeon, this is BTU.

Surgeon: Go BTU.

BTU: Best thing we can find out is we’re at least a half hour away from even starting preparation for EVA. But I was wondering if we might want to go back and reconfigure for one man coming out on the LEM for ECG.

Voice 5: Go ahead, Trajectory

Trajectory: Hey, I think those liquid cool garments weigh 3.6 pounds apiece.

Voice 5: Well, look, it’s, what I’d like to do is I’d like to get the best guess of what we think we got loaded, Trajectory, I mean in the dadgum spacecraft and run several sets of–

Madrid: Flight, Madrid, Net 2

Flight: Madrid Track, go ahead.

Madrid: Do you still see indications that we have two-way data?

Flight:Roger, we’re checking your teletype printout of your data now. We’ll get back to you.

Madrid: Roger.

[ Music ]

Host: John Hansen and his team overcame some incredible obstacles, but they succeeded. They transformed tens of thousands of hours of raw audio of American history from analog tape into the digital files that they would need to do their academic research. So how’d that turn out? Find out on the next episode.

[ Music ]

That’s three down and one to go. We have a final installment in this series coming up next time. When we’ll find out how the team turned digital audio into coordinated transcripts and added video and stills to make a terrific experience that you can enjoy yourself online any time. Until then I’ll just say “The Heroes Behind the Heroes” episodes of Houston we have a podcast are produced by Greg Wiseman and me. With editing and audio engineering by Greg and help from Alex Perryman. Thanks to our guests John Hansen, Tuan Nguyen, and Greg Wiseman. And to Norah Moran and Gary Jordan for helping us make this all work. Check out all of our podcast episodes at nasa.gov/podcasts. And while you’re there, you can check out all the other NASA podcasts that you can find. Things like “Welcome to Rocket Ranch,” “On a Mission,” “NASA in Silicon Valley,” and there’s more too. They’re all there right at the same spot where you can find us. nasa.gov/podcasts.