Episode 40: Sarah Cox, NASA

Sarah Cox, materials engineer at NASA, talks about her experience at NASA working with composites in the space travel space. 


In episode 40 of CW Talks: The Composites Podcast, Jeff Sloan, editor-in-chief of CompositesWorld sits down with Sarah Cox, materials engineer at NASA. Sarah has worked for NASA for more than 18 years and has experience applying advanced materials to space structures. Jeff talks to Sarah about her education, how she came to NASA and how she helped guide composites use there. 

Sarah Cox

Sarah Cox, NASA Photo Credit: Sarah Cox

Transcript of Sarah Cox interview with CW Talks 

Jeff Sloan (JS): Hi, Sarah, and welcome to CW talks.

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Sarah Cox (SC): Hi, Jeff. Thanks, I'm happy to be here.

JS: It's great to have you here. We're going to talk about your current job and your current work in a second. But before I just want to start with your education, tell us a little bit about where and how you were first exposed to composite materials.

SC: So I actually didn't really get involved in composites until about eight or nine years into my career. So I kind of have a kind of look at it as like, you know, the second part of my career. Initially I got my bachelor's degree in aerospace engineering from Georgia Tech and I was fortunate enough to get hired right out of college to work on the shuttle program at Kennedy Space Center. I actually worked in the thermal protection system, which is all of the like tiles and blankets that cover the Orbiter. And it kind of turned out to be a good introduction for me into nonmetallic materials and processing and bonding and that kind of thing. I worked on the space shuttle orbiter from 2004, until the program ended in 2011. We knew the shuttle would be retiring and everyone went through a bit of a transition period. So for me, it was kind of, you know, okay, I've been doing this for seven years or so kind of, what do I want to do now. So, you know, I had a few different options and opportunities to look into. But I ended up getting pulled into some composites project, able to do some hands on work. And I realized that pretty quickly that I really loved doing that. So at that time, there were a couple of NASA projects going on, that Kennedy was a part of, those were agency level projects. So we were working with other composites engineers from Langley, and Goddard, and Marshall and Glenn. So one of those was composites for exploration, which was looking at the advancement of large out of autoclave structures. And the other one was the composite cryo Tank Project, which we actually worked with, with Boeing to develop and fabricate a full scale composite cryo tank. And these projects were really great, because of the work that we were able to do at Kennedy, I got some good hands on experience making test panels, learning how to lay up composite panels, doing vacuum bagging, and all the fun challenges that come with that and getting a good vacuum. We also did some composite repair work. With all the NASA centers, each one kind of has their areas of specialty. So some are more into the research side, some are more into design, some are more into manufacturing. Kennedy has always really been seen as the place where, you know, for launch and landing, so, all of the flight hardware that's going to launch comes here gets gets integrated, gets processed for all the final processing in order to launch and, and even with the work I did during the shuttle program, a lot of it was making sure that the hardware was good for launch. And so, focusing some of our composite work on damaged composites and repair processes. That was a really good fit for us to focus on that Kennedy. So around this time that I was I was really getting this experience in composites. I had also decided that I wanted to get my master's degree. And with the previous work I had done I really found that I liked materials engineering. So it was a really good combination of being able to do my master's focusing on composite materials and the work that I was doing at Kennedy. And then kind of following that, I was actually able to work on a payload called advanced plant habitat, which is actually up at the space station, it has been there for about five years or so. And they're using it to grow different types of plants. This project was actually led out of Kennedy amd it was decided that we were going to build part of this out of composite. So I was part of that kind of design and development team. We actually did the fabrication work at Kennedy. So it was really exciting to be able to build something that is actually in space. 

JS: That’s really great. So before we leave the space shuttle, how did you feel about the space shuttle program being canceled? Do you have a soft spot in your heart for it? Or was it you know, just a job that you did, and you're ready to move on? What was it like for you?

SC: Oh, it's very much a soft spot, I loved working shuttle and getting to work around the orbiters every day, getting them ready for launch, getting to watch them launch, getting to watch them land, and then work on them again, that was a really fun program to work on. So it was sad to see it end. For us it was both, you know, having to retire the hardware but then also, a lot of the people that we worked with, everyone had to transition to different things. So, it was a pretty emotional time. But, when you look at the big picture of human spaceflight, and the space program, and budgets and how you're spending your money, I think that's it. At some point, things had to transition to move on to the next thing. So, you know, maybe a little bit bittersweet that I'm so fortunate that I got to work on that program. But it's also been a lot of fun kind of seeing the changes and kind of what's coming next.

JS: So, what drew you to NASA in the first place? Or were you drawn, when you came out of Georgia Tech, what attracted you to NASA?

SC: You know, I had decided in high school that I really liked rockets, I thought rockets were cool. That was kind of my decision of, like, if I want to do this, I want to go work for NASA. So getting my undergrad in aerospace engineering just kind of seemed the natural thing to do for me. And, you know, I had always thought Kennedy Space Center is really the place to be, this is where they're launching rockets from, and at the time the shuttle program was landing the orbiters here, so it kind of felt felt like the right thing. And again, I was so fortunate to be able to get hired down here and work on that program.

JS: I want to talk a little bit about your current role. Can you just describe for us the job that you're doing right now and how you evolved into that role?

SC: Yeah, so at Kennedy, I am basically the composite subject matter expert here, I mostly support the Commercial Crew Program, but I also support the Launch Services Program, which handles all the uncrewed launches, you know, launching satellites, and rovers and that kind of thing. But, you know, I have a really great group of composites engineers that I work with here at Kennedy, and really just across the agency. All of the centers all the programs, all those programs have some composites on them. So we really have a good community across the agency, sharing knowledge. In addition to, the work that I do here, it's also about kind of having those connections across the agency and being able to have access to the right folks to help you with your job. I think that up to this point, this community has been relatively small but it's growing pretty quickly, both here at Kennedy and across the agency.

JS: Can you tell us a little bit about the programs that you're working on that you're most involved with right now?

SC: Yeah, so I mainly support the Commercial Crew Program and we are working with SpaceX and Boeing on certifying their spacecraft and launch vehicles in order for them to take astronauts to the space station. So, you know, again, with shuttle, that was one of shuttles main jobs once once Space Station got built, was taking astronauts up there. So when that ended this was, commercial crew was the follow on to that to, to transfer that function to these companies to be able to continue to take astronauts. So, my role is to review and assess all of their composite structures, making sure that that they're meeting their requirements and that their, their vehicles are, you know, are certified to fly. And so it's kind of come a little full circle for me, you know, having started in the shuttle program. I do love working human spaceflight. But then having that time to get the the hands on experience and get some expertise in composites. This is a really good fit.

JF: So before we leave this idea of, well, before we leave the space shuttle again, I wanted to point out, I don't know how many people know this, but, you know, once the Space Shuttle Program was discontinued, the US lost the ability to send and retrieve astronauts to the space station. So we relied for many years on the Russians, correct? To help us transport to and from the space station. So just tell us a little bit about that.

SC: Yeah, you know, the Russians were basically, they're the only way that we could get people to and from the station. Once shuttle ended in 2011, until late 2020, when we really launched the first crew rotation back from US soil. All that time, we were really relying on them in order to take astronauts back and forth.

JS: How did that feel to you having worked on the space shuttle and feeling like being a part of a team that was, you know, helping keep that vehicle operating, and then having it go away? And then not having that capability for so long? I mean, that's, that's almost 10 years.

SC: Yeah, it's a long time to, to not have that capability. But development of these new vehicles to be able to do that, that takes time. And I think that, on the one hand, it, it is a long time. But on the other hand, all of the work that has been going into the commercial crew program to be able to do this again. It's been a lot of work. So yes, 10 years is a long time. But you know, on the other hand, it's kind of a blink of an eye, just with all the work that we've had to do to get here.

JS: Right, so nobody's been sitting around not doing nothing. 

SC: Oh, definitely not.

JS: Yeah. So let's talk about the certification process. Can you just walk me through what that looks like? You know, what is your role? And what is the role of the manufacturer? You mentioned Boeing and SpaceX? Obviously, you must work with them and communicate with them. Tell us a little bit about what that looks like.

SC: Yeah, so, like you said, SpaceX and Boeing are the two partners in the Commercial Crew Program. We have to certify their spacecraft on their launch vehicles. And, you know, for SpaceX, that means we're looking at the Crew Dragon and the Falcon nine launch vehicle. On the Boeing side, they're building the CST 100. And then they've actually contracted out to ULA, to use the Atlas five launch vehicle. So there's really kind of three different companies we have to work with on this. My role is really to do the review and the assessment of all of those composite structures. And so kind of where this starts is that we have our NASA standards, and these provide the requirements that have to be met for the program, part of the original contract. So there's three main ones that I have to deal with that have requirements relevant to composite structures. One of those is the materials and processes standard, which has requirements for every kind of material that that you could use and addresses everything from allowables to materials compatibility to requirements for special processes like composites fabrication and bonding and welding. The second one that I have to look at is the structural requirements. Specifically, I'm kind of looking more at what is being done for the qualification of the structural components, what safety factors they're being used, that kind of thing. Then the third one is the fracture control requirements, which fracture control deals with how you are assessing defects and damage, how you're handling damage tolerance, looking at flaws and flaw growth. Again, you know, the these documents, cover materials across the board metallics and metallics. Because of the nature of composites, to kind of pull those pieces of the requirements from each of those documents in order to, you know, kind of have that integrated approach for what we need to do for composite structures. So, when you're looking at design values, and allowables, that you're going to use in your analysis but with composites, you can't just take an allowables value from some published handbook, that doesn't really exist for composites. I mean, there has been a lot of development and in trying to kind of standardize that process and having that information, but you really have to understand your ply layup, your fabrication process bagging, you know, what your cure cycle is, you have to understand the design features and how that's affecting the loading going through the part. Then, back to that fracture aspect, you have to understand and account for defects that you could have in your part, you know, potential impact damages, and we don't really have established analysis methods to look at flaws and flaw growth in composites. So a lot of that has to be done through empirical testing to understand how that's affecting your strength. Also, you know, unlike with metals, you can have an internal defect or delamination that happens from an impact, with nothing visible on the surface. So, kind of understanding that damage characterization and trying to protect against it, and also understanding how that affects your structure. So, really what this comes down to is, it requires a lot of testing, you know, you kind of start at that coupon level to get your kind of your basic design values, but then you're also going up to kind of that next level with kind of making sure you're accounting for the different features, and for any defects that you kind of need to account for within your part. So that's basically how we have to use those requirements and kind of how we're really having to implement them, for now, is through a lot of testing. 

JS: Are you doing the testing yourself? Or are you depending on your partners, Boeing, and SpaceX and ULA to provide that data for you?

SC: Yeah, so, the way Commercial Crew was set up, this is a different approach from how NASA kind of typically sets up their contracts, especially comparing back to something like shuttle. So these partners, they are the ones that own the hardware. And so all of all the documentation and all of their designs belong to them. So, they're the ones that are having to do all of that work, and we're just working with them on on ensuring requirements are met. So with Commercial Crew, the first phase was to work with them to ensure that their documentation and their requirements, were meeting our NASA standards. And then when we got to kind of more of the demonstration phase where they're actually designing and building flight hardware. It's their responsibility to provide all the evidence for how they're meeting these requirements. So for me as the customer, it's my responsibility to understand what they're doing, how they're doing this testing, to review all that data, you know, make sure that they're, they're accounting for all of these things, all the configurations, all the conditions that that these parts are going to go through, and be sure that that's all a part of their test program. Then also, looking at those results, making sure we understand those results and working with the structures team, to make sure that those are being implemented into the analysis, that we understand how that's being done. But then, even in addition to just all the testing required, we're making sure we understand that the fabrication processes that they're using and that documentation, how they're inspecting their hardware, you know, what protections and mitigations they have in place to try to prevent any sort of damage that could happen during assembly operations or transportation. So we are working very closely with all the partners to, to make sure that all of these requirements are being met and, and that we understand how this is working. There's always going to be special circumstances, where things may not line up the way I originally planned. And so work with them on that too, just to make sure that we have an approach that everyone agrees to.

JS: Quick question, are the requirements for Commercial Crew the same as the requirements, say, on the launch vehicle? Or are you working with because they're performing different functions, are you working with different requirements, or they just sustain across the board?

SC: The requirements are the same, how you're meeting, those requirements may be different, just because of the different environments that you're in, whether it's the temperatures that you're seeing the types of loads that you're seeing. So it is really making sure that the implementation of those requirements is being met for all the hardware. So that's kind of all the initial stuff that has been happening and getting through kind of what we call the demonstration phase, where each partner had to do one uncrewed, and one crewed test mission in order to be considered, you know, certified and start that regular rotation of taking crew to the station. But even at that point, we continue to have insight into the flight hardware, what's going on with the flight builds any issues that come up any changes that need to happen? So, we're continuing to work with him on that. And, you know, the the current status of the program, Boeing, Boeing did have an uncrewed launch, they had an anomaly and so the decision was made to do another uncrewed test flight. So they're still kind of working towards that. SpaceX actually did make it through certification. They had both their uncrewed and their crewed test flights. And they've taken to two rotations of crew to station so far. Right now, what they call the crew to mission is up on space station. And then kind of the late October, early November timeframe crew three astronauts are going to launch and the crew two astronauts will come home, you know, so the two partners are in kind of different places at the moment. But it is a really busy time, you know, following multiple vehicles for each of these partners. But but we have a really great team, both here at Kennedy and also working with engineers at Johnson on this.

JS: What is the schedule for Boeing's next uncrewed launch? Do you know?

SC: I do not know at this time, I know that they're working towards something.

JS: Either for the uncrewed and crewed launches, do you require SpaceX and Boeing to provide information about the performance of the craft during those flights? What what kind of information do you do you need or want from them to make sure that craft are performing the way they're supposed to?

SC: Yeah, the team's work very closely together, through the entire cycle of launch and on orbit and landing to make sure that the that the vehicle is performing as expected. So there's continuous activity going on during that time for for composite structures, that it's typically pretty pretty quiet. When the vehicles on orbit there's not really a lot going on with that. But uh, but definitely during landing and splashdown and all the inspections that happen when the vehicle comes back, we're working with them to get that information and understand and make sure that there was any off nominal things that were found that that we're making sure that the next vehicle is is going to be safe to fly.

JS: I can imagine given the variability of composites materials and processes combined with the variability of the structures that you're working with it each project you work on must be unique and wondering if that's true and and what are the challenges associated with this?

SC: Yeah, I think one of the main challenges is just all the options in the composite material systems for all the possible combinations of different resin systems, different carbon fiber systems types of weave, so even just at the basic raw material level, each of these variables can change the properties of your material and of your final component. So it's even beyond, you have having different layups in different fabrication processes but if there's any changes within the material system itself, that that can cause you to go do more more testing to ensure that you understand how that change has affected your material and your material properties. And working with these different companies, means having to know about different material systems. So, you know, as we've been going through this initial development and certification phase, we have to kind of do a little bit of our own research into these material systems, you know, understanding what information is out there, and getting additional information from the partners for that. And then each of these partners has to do their own testing. And so then have to review all of that data. Being on the application side of things with aerospace, and something that is so critical, it is really important to understand your material and to have all those controls in place so that you're getting a consistent product every time. And of course, we want to see development of new technologies and composites of resins that can handle higher temperatures or material systems that are more damage tolerant, we need to be making progress in those areas. But as someone who is certifying or working towards the certification of things that are actually watching you, you want something that's kind of established at that time, just to make sure that you understand your your materials and your final product.

JS: Does that mean that your partners are only using qualified materials? Or is it possible for them to introduce an unqualified material into a program like this?

SC: Any material that they are going to use, we have to, there has to be qualification of that data out there. So they can bring something that maybe we haven't, that, you know, whether I personally may have not been familiar with in the past, but it's doing that research and understanding what that material is, and understanding the vendor process and how, and how the partner is using that material and looking at getting help from other experts across the agency to see if somebody else has some experience with that material. So holding on all the resources, you know, we want to work with a partner who's you know, the goal here is to succeed and if they think they have something that needs to be changed, or they want to try, they're trying something different, we of course, want to work with them to make sure that everyone understands, what that is and that we're all on the same page. And that it's, there's not any additional risk by using that material.

JS: Yeah. I'm sure you work with engineers at SpaceX and Boeing who were very familiar and comfortable with composites. But I wonder if there are any common problems or challenges associated with composite launch vehicle and spacecraft development? What have you learned in working with these various companies and people at different levels?

SC: Yes. In addition to the things we've already discussed, as far as different material systems and different configurations that they're being used for, the different companies do have different approaches to how they want to meet the requirements. There's not a set proscribed way to exactly what you have to do to meet the requirements. And so, so being on the NASA side, it's kind of an interesting position, because I get to see these different approaches that these different companies use. Sometimes it can bring some challenges if it's something that we aren't familiar with, but it also brings a lot of interesting conversation and to looking at different ways that requirements can be met different approaches that can be done, you know, that are still going to provide a good result in the end. So it always makes for interesting conversation, and it's really, it's good to be able to see those different approaches and different ways things can be done. In addition to the NASA composites community that we have, I'm also involved with composite materials handbook, which, you know, we call CMH, 17. This handbook, it really started as providing guidance more on the, you know, for for FAA, and on the aircraft side, there are differences in kind of the life, the life of a spacecraft versus an airplane and the environments that they see, but there's a lot of similarity to as far as the the development of, of allowables and damage tolerance testing that needs to be done. Actually, through this community, we do have a have a group, from the aerospace industry side of things that, that is working to put together some guidance kind of geared towards the space applications. This group includes those of us from the government side, as well as private companies. So, it's a really good mix of, of people and ideas, as far as looking at different ways to, to approach how to have safe human spaceflight.

JS: You said guidance, what kind of guidance do you mean?

SC: Guidance, as far as types of testing that should be performed? How much testing should be performed, considerations, as far as having different lots of material and understanding your your fabrication process, looking at, what do you have to consider as far as defects and damage and what testing should be done for that and what they call the building block approach where the coupon level, you're doing a lot of coupons to get your basic allowables values, but then as you kind of go up that building block, when you're looking at kind of sub element level, and you're using that to kind of correlate more to your analysis, and then, up to a full scale, where you're only going to do maybe one full scale article, testing at that level. So, a lot of that kind of information as far as just what the testing needed and kind of how do you incorporate those results into the design? Because designing for composite structures, I think is very different than designing for metals, we really have to consider, you really have to consider, your your manufacturing processes. You know, upfront as far as how you're going to design that part. I think there's been a big push for also designing for damage tolerance, making sure that your your hardware has damage tolerance, or that you have good ways of inspecting it. So it's really that that handbook has been been around for decades, and it's continued to get updated with more of the latest information and trying to to provide, you know, the best information that we have, based on new data, new technologies.

JS: Are you talking about enhancing the protocols and standards already in the handbook? Or are you talking about developing more space craft specific standards separate from the handbook.

SC: So, the handbook itself is really more of a guidance for how to meet requirements, because even just looking at the space side, NASA has different requirements than the DOD for their launch vehicles and their space hardware. And this is part of what is good with with this group is kind of the exchange of ideas on why we have certain requirements and why they may have other requirements and in the end, it's all really meeting the same intent. So the idea of putting guidance into the handbook is to allow someone who maybe isn't as familiar with building composite structures for aerospace capabilities to kind of help them navigate maybe what some of those standards and requirements are trying to say. The requirements have to be fairly general, because there's a lot of different types of structures and types of environments. And so they have to stay general. But then when you really start to look into specific applications and providing some examples of here's how this structure could be designed to meet these requirements.

JS: Okay. Where do you see the most activity in composites, materials and processing right now? You mentioned that your partners come to you with maybe creative and slightly different ideas about how to meet certain requirements and certifications. But I can imagine, also, they must come to you with some ideas about how to apply some new technologies as well. So can you talk a little bit about what you see on the horizon? And what's being explored for spacecraft?

SC: Yeah, from what I see from these launch vehicles and spacecraft, there is a push for large out of autoclave structures, and aerospace companies have typically been using autoclave materials, because you're typically going to get a higher quality, more controlled, lower porosity, from having that autoclave process. But as they look at building larger single structures, we're kind of outgrowing autoclaves and having an autoclave and building a bigger autoclave is a huge expense. So we are seeing a push towards that development of out of autoclave materials, that will still produce that high quality part that we need. Another reason to build these larger structures, as you know, a single piece is to eliminate the need for joints and having to put a bunch of fasteners through your composite part, that kind of defeats a little bit of the purpose of having a lightweight composite part if you're then having to go putting metal through it for all these joints. I think there is a lot of benefit to having these bigger structures and eliminating that complexity of having joints. Speaking of joints, there's that area of bonding, bonded joints, bonded structures, there's still work to be done there. Bonding is a tricky thing. Making sure that you don't have any contaminants, that you have good surface prep, that you have a robust bonding process and that you're getting consistent results every time. That is still I think, doing that and having a way to verify that with every build that you do. I think there's still some challenges there that that the industry is working through.

JS: You mentioned earlier, the challenge of damage from impact and the fact that it's not often visible. I wonder if there's any concern about sending a craft up a crewed vehicle say the possibility that it sustains damage that goes unnoticed or unrecognized, and then introduces a potential flaw into the structure that could be life threatening to the crew when the crew returns? I'm sure this is a kind of thing you think about every day, but I'm wondering what you think about that, and how that factors into some of the work you do?

SC: Yeah, designing for damage tolerance is a huge part of what we do. I will say, launching rockets and human spaceflight is a very challenging thing and you're never going to eliminate all the risks. But we work really hard to to reduce that risk as much as we can. So in the initial design phase, that's really where this kind of stuff needs to be included and thinking through where are we most sensitive or most critical to impacts and how are we ensuring that we have a good design for that and trying to think about all those scenarios of what could happen and how are we protecting the structure or are mitigating some process to try to prevent that from happening. So that is definitely a big part of the entire process of making sure that we're not going to have a damage that could result in some, reduced capability beyond what we're able to handle. 

JS: Is that challenge often met via redundancy or via just a robust design? I mean, I'm sure the designs are robust anyhow. But is there a strategy there for meeting that? That damage challenge?

SC: Yeah, and I think, unfortunately, at that moment, that's why there's so much testing that needs to be done up front. So you're not only doing your testing to understand your compression and tension, strength of your material and your layups, but you're also having to do testing where you are embedding defects to understand how does that affect the capability, it's often we do you what you call compression after impact testing, where you're taking tests, coupons, doing different levels of impacts, and then doing mechanical testing to understand how that reduces your capability. That is actually a big driver for the design values that we use, because we're basically designing in that damage tolerance to say, you could have an impact that didn't get detected and at a certain level, but the structure is going to be able to handle that, because we've designed the part to be able to handle that.

JS: Okay. Right. So final question about damage. And then I want to talk about the future. I can also imagine a crewed spacecraft goes up to the space station and the damage is detected and perhaps that damage is significant enough that it affects the ability of the craft to return to Earth. You mentioned repair earlier, are there procedures or processes and materials in place that would allow say, an astronaut to perform a repair on a on a crewed spacecraft at the space station? I can imagine that would be very difficult.

SC: So currently, no, not that I'm aware of. It has to do more with the contingency planning from keeping the crew there and being able to get a spacecraft there that is safe. So yeah, station is a great place. Not only are people living there and doing a lot of research there, but then yeah, it's allowing for that opportunity to if something does happen, having that time to be able to react to that and, and have contingency plans in place for that.

JS: Yeah. Alright, so let's talk about the future. I know that NASA's partners, Boeing and SpaceX have big plans to send spacecraft and people back to the moon eventually, Mars, I know, you know, Elon Musk has talked a lot about going to Mars. This must have introduced a host of mechanical and thermal and ballistic and other challenges that must be met by composite materials. I'm wondering if your job requires do you think about these things and what kind of evolution in composites M&P is going to be required to meet these challenges, do you think?

SC: Yeah, I'm very much involved in what's happening right now with these launches but Commercial Crew Program is really a small part of the bigger picture of NASA, even just looking at the human exploration side of things, you know, there's a lot of work going on with with getting back to the moon and getting to Mars. The Artemis program is in development, and they're trying to get those launches happening here in the next few years. Even just beyond that, and you can even see with Artemis, much more of that vehicle uses composites than Apollo or even shuttle. We even see from the commercial companies, the ones that I work with and even Blue Origin, Sierra Nevada, they're starting to use more composites in a more strategic way. So, even what we're seeing, from I'll say, more of a short term with these, this kind of new generation of launch vehicles and spacecraft, there is a lot of room for for development there and making those lighter, more efficient launch vehicles. But, you know, it's not only about, how do we get to space, but also, how do we live there, and I think composites are a very important part of that. We're going to have to, there's a lot of work and learning how to use resources from these other planetary bodies to actually build things to build structures. We are going to have to develop ways to do repairs in space, you're not always going to have the option of coming home. Not as a quick option. We need to be able to have these ways that people are really able to live in, in space and, and have the resources that they need. And so I see composites technology playing a big role in that for the future. I know a lot of work is going on, both around and within NASA and with all the partners that they're working with, to do that. You mentioned things like thermal and ballistic and that kind of thing. I'm not really involved in this, but I know that there's a lot of work going on to get higher temperature capabilities, development of hot structures. So, right now, with a lot of our spacecraft and any of the launch vehicles, you have to attach a separate thermal protection system to your structure to keep the structure below a certain temperature, but with the development of those higher temperature capabilities, you can reduce weight even more by not having the separate system for that. So there's a lot of different areas where I think composites are are going to be a big benefit.

JS: Well, I'm wondering, we were talking earlier about launching and landing and the you know, the material performance in different stages of a spacecraft’s performance. I think my observation has always been that launching a spacecraft is really, really difficult because of gravity. Which sounds kind of elementary, but overcoming gravity and getting a mass off the earth and into even into orbit, takes a lot of energy and effort. I'm wondering, when you think about sort of the life of a spacecraft when it travels up and comes back? Where's the greatest opportunity for, for damage? Or where does that spacecraft see the most mechanical stress when it's going up, say to the space station and coming back down.

SC: So, as far as the performance of the structure, the mechanical stress, launch, launch and landing, obviously launch vehicles their big thing is the launch, but even now, we're seeing with what SpaceX is doing with the reuse of their Falcon nine, first stage, they're also having to design for that reentry and landing. So, those are definitely for spacecraft launch and landing. And now we're seeing even for some parts of the launch vehicle, they have to design for launch and landing. The on orbit portion, from a structures perspective is usually pretty low concern. It doesn't really see a lot of loading. When you talk about damage, you know, again, my perspective is coming from working here at Kennedy and doing a lot of ground processing. And I think the aircraft side of things will tell you this too, that really being on the ground and having people work on the vehicle is where you’re most sensitive to getting damage. We put protections in place, we have mitigations, everybody understands the sensitivity of composites hardware, but human nature and having people work around these vehicles, things are gonna happen. So it's about having the rates the right processes in place to try to prevent what you can and having a good reporting mechanism in place so when things do happen, that everything is getting assessed correctly.

JS: So if if somebody drops a wrench on to composite structure, you don't want them to not report it, you want them to feel comfortable coming forward and saying this is what happened, this is what I did. And, gosh, I'm really sorry, but you need to know that this happened. And there that has to there have to be processes in place to make that OK and to facilitate that. Because I think human nature, like you said, human nature tends to want to, to not fess up when we make a mistake.

SC: Right. And so it's about developing that culture of we, our number one job is to protect the astronauts. So making sure that the launch vehicle and the spacecraft are going to perform their job safely. And making sure that everybody working on those parts understands that. Especially with composites, people who haven't worked around composites may, you know, drop something and think, oh, I don't see anything. So it's about making sure that everyone has that training, they understand the sensitivity of composites. And so that they know that they need to report that to be sure that that gets assessed.

JS: Okay, final question. This is an easy one. If you were given the chance of spaceflight, how far would you go? So, you could go either, so let's say low earth orbit, so the space station. Would you go to the moon? Or would you go to Mars, or maybe further than Mars?

SC: So, you know, I have a degree in aerospace engineering. So people do ask me, do you want to be an astronaut? My immediate answer is always no. I love being around rockets, I love watching launches and I am really excited that other people want to go to space. But I don't, I guess have that same sense of adventure as far as as going to space. But, you know, these are really interesting times right now. Up until this point, it's really been government agencies sending astronauts and cosmonauts to space. And now we're seeing this shift to what's been going on with Blue Origin, and Virgin Galactic and SpaceX with, you know, taking private citizens to the edge of space and to orbit the Earth. I think this is an exciting time to see all that happening and you know, opening the door for, we'll say, us normal people to be able to do that type of thing. So I hope that that opportunity continues to grow.

JS: Well, I think you're right, I think this is an exciting time and I think it's gonna be really interesting what the next, I don't know, couple decades, 50 years bring. But I obviously the work that you're doing is critical to protecting our astronauts and protecting the the folks we're sending up to the space station and probably beyond. So I thank you for that work. It sounds very interesting and I appreciate you coming on and talking to me about the work that you're doing.

SC: Thank you so much for this opportunity. It's been really great talking with you, Jeff.

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