There was the crew giving our experiences – what we saw, or what we heard or what we felt – back to the engineers, so they can learn from that going forward, and then there were separate debriefs where the engineers are debriefing Dragon, Falcon, operations. They learned some things from us based on our experiences, and then we learned some things from them based on what they learned from the vehicle or the booster.

Space adaptation syndrome is certainly real. Approximately 50% have [had the syndrome] happen throughout spaceflight history, across NASA astronauts and such. There’s not a whole lot up until now that you can do to predict it. You [even have] hardcore fighter pilots that just get sick in space. What they do know is the recovery is very quick – usually even without medication it’s less than 24 hours – and they do know that certain medications will reduce it even further. In terms of just general odds, those odds played out with us. The medications made it a shorter recovery and everybody was happy and healthy shortly thereafter.

What I do think was interesting is that for SpaceX, given their objective to put like potentially millions of people in space someday, we did participate in a research experiment before and after the mission. Based on the data so far, and it’s a small sample size, they would have predicted 100% would have been faced with it. So that’s good because now maybe there’s a different medication that those people who are susceptible to it could take before launch and minimize that impact … it reinforces the real role of a medical officer on a mission because, as much as we want to turn this into airline travel, the reality is you do feel very different in space … that can lead down a path where some medical treatment is warranted, so having Hayley Arceneaux on our mission to start divvying up shots as required was pretty important and that will be something they maybe even want to expand upon.

I was assisting Hayley in helping our other crew members, and I would say that it presented in two very different ways: One was very much like typical seasickness, motion sickness – where you’re happy and then all of a sudden, you’re like “I don’t feel so well” and then the other I would say was much more gradual, slowly building. Again, not uncommon from what we have heard from NASA and others. It presents differently with people. For me, I didn’t actually think anything was out of place. Obviously you’re looking out the window and you’re seeing Earth and that’s moving and then you’re in a spacecraft now that can move on all axes while you’re floating inside it and I think, for some people, maybe the combination of all three is a little bit of a sensory overload.

As a pilot you instruct people, as they move into higher performance aircraft, the concept that you always have to stay in front of the jet and that things will continue to happen faster and faster for you, where the time to make decisions needs to be quicker. But to be honest, as I progressed through my aviation career, I never really noticed those leaps that much.

It absolutely is that case in a Falcon and a Dragon, because time is moving very slowly right up until the last 10 minutes and then it just moves at this exponential pace where, before you know it, minutes are disappearing as if they’re seconds. It did not feel like 10 minutes; it felt like, I don’t know, 20 seconds.

You hear everything. [NASA’s] Crew-1 told us that too, when we spoke to them, that Dragon does, as they described it, come alive … The first thing is the launch escape system, because you have to arm that before you put propellant on and that is a very loud noise as valves open and the system gets charged … so you feel that thud, and then it’s only seconds thereafter before you actually hear grumbling propellant loading onto Falcon and then as tanks are starting to fill and you have venting you hear that. You hear valves opening and closing. It’s not very mechanical sounding – I would describe it more as a rumble … and you’re hearing that right up until essentially the last minute.

You do feel as the transporter erector, the “strongback,” retracts, because there’s just a little less stability so even a little bit of wind you feel … by the time you hear the countdown of one, you’re already feeling the sensation of liftoff. There’s a delay in the radio so you’re seeing the bloom of the engines come alive on the screens and before even the countdown hits one you’re already on your way up. It is not the big G event that people think because you’re actually going rather slow initially, so you sense the motion, but it’s nothing like being in a car and somebody slamming on the gas.

You hear and you feel the throttle up and throttle down, so going through Max Q … when those dial back, it is noticeable. You also do feel the pitch over – so as Falcon’s pitching down range – you can see it on the screens but you can feel it too, that it is changing its attitude at that point. It sounds loud, but what you’re hearing is the turbo pumps driving at max performance. Once you’re going past the speed of sound it’s really what is on the vehicle that you’re hearing.

It’s instant. It’s actually the same feeling that you have at stage separation. At stage separation, before the second motor ignites, to me it was a huge unload. You’re practically at a zero-G event at that moment. It’s the same thing when you get on orbit, except that it never starts up again. It’s continuous. And the best way to describe that would be hanging upside down from your bed, like your head fills with blood.

You’re still kind of on your terrestrial up, down, left, right when still strapped in. The moment you unstrap and you start working in space, you don’t care anymore. You’re not bounded by that at all. You could be just as comfortable upside down facing the floor and that wouldn’t feel that unusual. That said, I would say most of the time you are still oriented where the cupola is the top and and the floor is the floor.

When I made that call down about the doors opening up a bit, I was just looking under the screen and looking out the two forward windows and it looked like if you watch space camp, whether it’s rendering or otherwise, it looks exactly like everything we’ve ever seen: “Holy s—, there’s Earth through the window.” I wasn’t surprised that it looks so much different than I thought it would be. It radiates more and it’s higher resolution for sure — you’re seeing it with your own eyes — but it looks pretty much what you would expect it to look like.

It was a very tight schedule and it went by very quickly. It did not feel like three days. We got behind on our schedule the first day, which is exactly what was predicted based on a long simulation, that if even one person is feeling unwell – and to be clear, no one vomited, it’s just an unwellness feeling where you just take your meds and you just ride it out. But if even one person is down, the workload increase is pretty significant, so we did have two that were down for some period of time. Despite good efforts you’re really behind on the first day. By the morning of the second day, we woke up early, which is exactly what we did in the 30-hour sim to get ahead, and you’re right back on track and now everyone’s feeling good. And then by the third day you’re even better because whatever adaptation your body’s going through it’s kind of at its strongest by that point…. We went from behind on schedule to ahead of schedule by the third day.

This was another one where it was a 50/50 thing, where like 50% of astronauts say they love sleeping in space and 50% really don’t. And with us, one really loved it and three weren’t in love with it. One of the things that happens, versus being in your own bed, is while you’re sleeping you turn into a board – your body just straightens out. It just happens, you can’t like kind of curl up, you don’t have like the same benefit of cocooning like in a one-G environment. That leads to back pain. I had it, too. I would say it’s very minor, but the moment you start working again and moving around it goes away. But lying like a perfect board, like in a plank all night on a hard floor, is kind of what that feels like. Hayley, she had no problem at all. She just loved it.

We all were tired – so I would have thought like hey, “I can go to Vegas, think of it like a bachelor party weekend, you’re just gonna be up for three days.” But no, I was just so exhausted, as was everybody at the end of the day. [We slept] for like four to five hours a night; nobody slept eight hours.

It was one of my regrets, not changing the pointing mode. We have a “Sun+GEO” mode and it’s better communication, but it points the cupola towards the star field. And I don’t know why none of us really thought about it, but we didn’t.

The reality is, in all of the emergency [situations], where you actually manually bring Dragon home, it has to be really bad and the most likely time it’s going to happen is right when you get on orbit. If you can’t separate from the second stage, that’s an immediate ‘come home’ because you jettison the trunk and that’s a manual re-target back, because there’s not enough time for ground [control] to upload a burn to get you back to a supported site. Or if you have a major communications failure – you don’t launch with your [return site] already pre-loaded in Dragon – so for as autonomous as it is, [Dragon] has to be told where and when to come home. It’s not pre-stored in the computer … for that to actually happen on orbit after the downhill plan has already been uploaded, which happens within the first 12 hours, it’s got to be a fire or depressurization or a micrometeorite hit that’s pretty bad.

Nothing I wish I would have brought. In fact, a lot of my feedback to SpaceX was they should have been harder on us to take less stuff up, because it’s just a lot to manage. A lot of the cargo locations are hidden behind panels and it’s a real pain to get stuff in and out. My regrets are really small stuff. I felt like I was very driven on a timeline to just “stay ahead of the jet,” don’t get behind … I was always busy – that didn’t mean that I didn’t take pictures – but could I have taken an extra second, to stage a picture better? Could I have wiped down the cupola, where there was a smudge mark? It’s little things like that, that I was mad at myself for just not pausing in the moment and just trying to get it a little more right.

The single most impactful moment for me was the moonrise.

That just made me think that we’ve got to just get our a– in gear a little bit more and get out there. It’s so hard, because I’m totally in the same camp as Elon; that the vast overwhelming percentage of our resources should be spent on making Earth better. But even 1%, or a fraction of a percent, can make such a bigger difference out in the universe. And if you could imagine trying to explain to somebody from 200 years ago what a cell phone represents, what virtual reality is, what augmented reality is, what jet transportation is – all of these concepts, that to us have positively impacted our lives, made us more productive … the world has gotten better because of technology that a person 200 years ago couldn’t even imagine.

Well, how much more of that is out there if we just go and explore this vastness of space that we know literally nothing about? Really, in the grand scheme of things, we know nothing about it. So there’s a degree of frustration that I hope in our lifetime, or at least we set up the generations to follow a little bit better, so that we can go across the oceans and climb the mountains again. So that was the feeling I had looking at the moonrise. There were happy moments of course: Chris playing a ukulele – where I’m quite sure if it was on Earth, we would all find anything else to do but if you’re in space, you’re like, “man, this is cool” – watching your crewmates eat and be happy, watching Sian paint. We got to watch everybody be who they are, which was pretty cool.

In general, the climate of Dragon was awesome. Crew-1 told us it gets really cold; we didn’t find that at all. We do have the ability to manually adjust temperatures – this is not like in your car, your thermostat. Coming downhill is nothing like the movies where everybody’s sweating and there’s condensation everywhere and there’s a fireball out the window. You only see pulses of what I would describe as like a fluorescent type light coming into the window. And it’s pulsing, it’s not continuous. It’s like a flash of yellow, a flash of purple, a flash of pink, a flash of orange – which is exactly what we saw from the Crew-1 footage, so nothing surprising about that at all.

Temperature was normal the whole way down. There is a cooling process that begins prior to re-entry to just adjust the cabin, but you don’t know it because you’re in your suits and you’re getting air, that’s basically your climate control. You absolutely know when you hit the atmosphere. We’d done 50 re-entries in training and you know exactly when you’re going to hit the denser part of the atmosphere … The deceleration starts happening quick and the G build-up starts happening and as you get more and more into denser atmosphere, you’re still going at a pretty substantial velocity. The G’s build up and it actually hurts a lot more than than the uphill because your body deconditioned over three days. So that was actually one of the debrief points I said, is that in the centrifuge profiles, [SpaceX] should add one G to everything on the re-entry because your body is feeling it more on the way down than on the way up.

In the simulators, I would recall, from the time deorbit sequence would begin to splashdown it’s about 70 minutes or so … there are gaps of time where nothing’s going to happen – and then it just disappeared, the last 80 kilometers. In fact, for a triple flight computer failure – which is one of the worst things that can happen other than a fire or a depressurization – in our checklist, you have to be able to start the process no later than 20 kilometers [above the water] because it takes 90 seconds to reboot all three, and if you’re less than 20 kilometers then you just plan to manually deploy all the chutes. When I think about when I saw 20 kilometers versus when we hit the water, it felt like five seconds. So I don’t know how, at that moment, you would have you’d be able to do that – I think you’d just be focused on getting the chutes out. You definitely feel the chutes big time, the drogues and the mains [a drogue is a parachute which deploys at high-speed, before the main parachutes].

Hayley will talk about how she looked at the G meter and saw 0.2 Gs and she’s like: “Wow, I feel that” and it’s true. It’s like an elephant sitting on your chest for probably eight minutes or so.

When the drogues come out it’s the sound that you want to hear of the mortars firing – those are pretty loud. From there, we have a camera looking straight up, so you can see if they come out nominally, and then you have a vertical velocity indicator that shows if you decelerated within a nominal range and then, third, you’ve got a WB-57 [a NASA supported aircraft] up there that is talking to mission control. Right about the time we see the velocity slow, you get the call from mission control that we see two healthy drogues. That lasts … 10 seconds or so, and then the mains come out. That’s another smack.

The way I’ve described it: Imagine just being in this tin can and somebody shaking it – it’s a lot of lateral forces, where you’re getting jerked around like that a little bit. And then the next is splashdown, which is just like getting rear-ended with a car, you’re like, “I’m just sitting here and somebody smacked me from behind” – that’s what it feels like.

Everything feels heavier, but your legs the most. So maybe your arms feel like 10% or 15% heavier, but your legs feel like 40% to 50% heavier. And then it’s a coordination thing where your ability to tell what is level is degraded. We’re all slightly different on that – I was probably 90% physically there and 85% from a coordination perspective, which is totally good. It was much more the rocking of the boat that they were probably worried about than us just falling over. I’d say everybody was generally in the same ballpark, plus or minus 5%-10% percent.

We landed, they did a bunch of medical assessments and fluids, if anyone needed, on the boat. You change out of your flight suit and then they chopper you off as fast as they could. We touched down at the Shuttle Landing Facility, we got out, they let us have about 20 minutes with our families to give them hugs and everything. And then they took us to one of their buildings for medical checkups. This was really important – which we emphasized in the debrief – is that you want to see your families, you want to let them know that you’re okay and ease their concerns, and then you need to check out for a little bit.

We got pulled away for the checkups, which was really smart. And while we were all sitting around this conference room table waiting for our turn on some of these tests, somebody pointed out that Elon tweeted that he’s in for $50 million. And then we knew at that point we were at like $218 million. It was just a very emotional experience for all of us – I don’t think there was a dry eye, because it just meant that what we did mattered that much more. And there is a lot to it, because Elon inspires the world with self-landing rockets and everything he embarks on. But we were able to inspire him to put some of his resources towards a cause. Maybe he would have done it – I have no idea how much of a relationship he did or did not have with St. Jude – but I’m highly confident he wasn’t planning on making that $50 million contribution until he got impacted by Inspiration4.

I’d say that every one of us had a little bit of an empty feeling at one point or another. It goes away pretty quick but, in the first five days from coming home, we all had something. With me it was deleting all the standing calls from my calendar, because there were a lot throughout a week and I was like “wow, I’m never going to do this check-in call again.” This was such an intense – super intense – part of our lives. The idea of going to space and coming back is intense in general, but when you’re on SpaceX’s timeline – clearly they do things in months that other people do in years – and you’re living it … you’re at this pace, you hit this peak and then it just drops and stops.

I think with Hayley it was when she got back home and she was unpacking all of her Inspiration4 medical officer shirts and she’s like: “I may never wear these again, I may never pack to go to Hawthorne again.” Everybody had it a little bit differently. But then you get back and you start thinking about: “Well, what’s my job now?” Well, share the experience, put pictures out there, talk to you, tell you what it was like so you can tell others, give SpaceX the feedback they need so the next mission is even more successful.

Before launch I had a pretty high bar for another mission, in that I’ll never do a joyride. It has to have real responsibility, it has to make a real difference and and I have to somehow be in a position where I’m the right person to do it or somebody else should, somebody who hasn’t gone.

So that was the bar before. But when we came back, looking at all the objectives we set out to accomplish a little under a year ago – finding an amazing crew, bringing us all together, delivering an inspiring message to people (maybe some of it has nothing to do with space: Hayley overcoming adversity at an early age, Sian never giving up on her dreams) – and reaching people with that message, I feel like we did all that. And then we said we want to solve a real problem, or attempt to solve a real problem, here on Earth by partnering with St. Jude. We set a $200 million goal and we exceeded that. We had other things that are impactful but still important – you want to make every moment on orbit count – we signed up for a bunch of research with Cornell and Baylor, you want to go past the space station (because why not, if you’re going to go to moon and Mars). We checked all those boxes … So that just raised my bar even higher because I would never want to do anything that would take away from the legacy of Inspiration4. My bar is really high on a very impactful, meaningful mission. If something like that does come around, then, yeah, why wouldn’t I want to go back?

One final point that doesn’t usually come up much in these conversations – but I certainly try and draw as much attention to as I can – is that SpaceX is an incredible company. I know Elon can be a controversial person, but his company is incredible. We were just the lucky beneficiaries of their effort over the last 20 years. They’re all really extraordinary. I would hire like all of them if I could, except they’re working on making life multiplanetary so that’s also a very high bar to eclipse.

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