[[Home|🏠]] <span style="color: LightSlateGray">></span> [[Interviews]] <span style="color: LightSlateGray">></span> June 10 2020 **Insider**: [[Peter Beck]] **Source**: [SpaceXCentric Youtube](https://www.youtube.com/watch?v=kFX2rPvIWqo) **Date**: June 10 2020  🔗 Backup Link: https://www.youtube.com/watch?v=kFX2rPvIWqo ## 🎙️ Transcript >[!hint] Transcript may contain errors or inaccuracies. **Interviewer:** Last year SpaceX announced that they were going to enter the small-sat rideshare program. The first thing I thought of when I heard that was "that's Rocket Lab territory." I wonder what Peter Beck thinks about this. **Peter Beck:** Competition is always a good thing. Although it's kind of a slightly adjacent market because the customers we fly are dedicated launch vehicles, not in the rideshare market. We don't really feel too much of an effect from there because the kind of customer that comes to Rocket Lab is the kind of customer that needs a dedicated launch. They need all the things that dedicated launches offer them. For the emerging one-ton vehicle class, it's a pretty bold move. It makes it very difficult to close the business case on that sort of one-ton vehicle under development. So for us, not too much of a big deal, but always welcome competition. ### The Importance of Space Technology **Interviewer:** While I was writing the script, I really like to feature you in my introduction. At least a snippet of your face to really bring the audience in. So you hear people say all the time, "We should focus on problems here on Earth instead of going to space." How would you respond to that? Why is rocket science so important? **Peter Beck:** Let's turn off the GPS constellation and see if everybody has that same view. The reality is that space is a place where infrastructure is built to support everybody down here on Earth. The amount of infrastructure that everybody relies on—whether it be communications, GPS, imaging—goes on and on. You could say that, but the reality is that a lot of people don't realize, because of thin infrastructure, how much they rely on that infrastructure every single day. Rocket Lab's mandate is we go to space to improve life on Earth. That's really the whole point of building and continuing to build space infrastructure. I think if we want to continue enjoying the lives we have, we need to continue investing in space infrastructure. But equally, if we want to advance as a civilization, we need to continue to invest in space, whether that be infrastructure or human spaceflight. It's imperative that the investments are continued and we keep going. It's very easy to focus on all the problems we have down here on Earth, but a lot of those problems are either solved or mitigated by infrastructure in orbit. ### Electron Rocket Recovery and Parachute Systems **Interviewer:** Last year Rocket Lab announced that you guys were going to try to reuse your boosters of the Electron rocket. I think it was about a month or so ago you released some pretty awesome footage that got me so excited when you did a test run of that drop. What made you guys as a company move more toward parachutes as opposed to propulsive landings? **Peter Beck:** It's pretty simple really. In a propulsive landing scenario, you have to withhold 30 to 50% of your payload margin to be used in the retro burns in the landing. For a small launch vehicle, you just don't have those kind of margins to play with. You turn a small launch vehicle into a large launch vehicle. Really, the only solution for us—and this is part of the reason why I originally felt it wasn't feasible to do recovery on Electron—is you've got sort of 10 to 15% descent reduction and payload to play with before it becomes unmanageable. The only solutions that consume that little amount of payload mass fraction is to let the atmosphere do the majority of the work. We end up pretty quickly at aerodynamic decelerators and parachutes to be able to meet those mass fractions. Of course, what you trade with that is infrastructure—in our case, it's helicopters and boats and those kinds of things. You put the complexity into those kinds of things rather than the complexity and mass into a propulsive landing booster, which is much simpler logistically but technically very, very difficult. **Interviewer:** So you're basically letting gravity do the work for you as opposed to fighting against it, huh? **Peter Beck:** Exactly. We let drag and air resistance and the re-entry work for us, and then use a parachute at the end. ### How the Parachute System Works **Interviewer:** Can you tell us a little bit about how the parachute system works with your recovery efforts? **Peter Beck:** The hardest part of the recovery is not actually the parachute descent stage element, it's the reentry element. We reenter at such velocities and we have to have control over the stability of the vehicle. We have a very narrow corridor, and we basically push a big bow wave shock in front of the vehicle and kind of sit behind that bow wave shock of supersonic flow to transonic to subsonic flow to keep the vehicle together in one piece and cool, and then control through a very, very narrow corridor. Once we get through that corridor, then we can start deploying the more traditional parachute systems. I've done a lot of work with recovery systems and parachute systems from our sounding rocket days. At the end of the day, the reason why parachutes are so challenging is you're throwing out a piece of fabric at greater than supersonic speeds. Imagine traveling in your car at supersonic speed and throwing out a handkerchief or a bedsheet—it's really complicated. The engineering behind it is really beautiful because it's very passive. There are lots of rules that you can design to, but at the end of the day, it's one of those things where you just have to go out and test. There are the bibles and the books and there's a lot of experience that goes along with it, but you get to a certain point and then you have to go out and start testing and iterating. **Interviewer:** When I was researching for this little documentary, I learned a lot about the Apollo program and how the parachute system for the Apollo capsule worked. They used what they called a sequence controller connected to barometric sensors and used mortars and things. Is it pretty similar to what you guys are using? **Peter Beck:** Yeah, exactly. Our kind of recovery chain begins with a mortar on a little pilot chute. When the pilot chute comes out, you need to make sure the risers are taut before the pilot chute inflates because if the pilot chute inflates before the risers are taut, then you get this massive shock load. After you deploy the pilot chute in a deployment bag, the first sequence is that the mortar waters out the deployment bag, the riser lines go tight, and there's a sequencer where the mortar bag is stripped away. You get nice tight risers, and then the pilot chute inflates well. Once the pilot chute inflates, it creates a pull, which pulls out another deployment bag, making sure those risers are nice and tight. It shears off that deployment bag and stages a nice drogue opening. Once you're under that drogue, there's quite a lot of aerodynamic load there, and you scrub velocity quickly, but you're also rendering the Earth's atmosphere quickly, so the air density is increasing rapidly as well. Once you've got it tidied up and under control, you're really down quite low at this point, because you want to use as much of the atmosphere to do the deceleration as possible before you throw your main out. We get down relatively low at that point, about 20,000 feet, and then deploy the main. It's the same scenario, except the drogue is carrying a lot of load, so you have to strip away the drogue. We have separation systems—the same separation system that we use between stage 1 and stage 2—carrying those loads and a pneumatic system where we cut the risers away. The risers come away and they pull out, once again, a main chute in a deployment bag. The risers go taut, it's all staged, and we strip off that deployment bag, and then the main chute is reefed. The main chute is not able to fully open; there are multiple reefing stages to that chute. The chute is held reefed for a period of time to lower the loads, and then you cut the first reef away and allow for a little bit more inflation, a little bit more deceleration. You cut the final reef away to end up at your terminal velocity, at which point you're at about ten meters a second and sort of six thousand feet off sea level. In the prev-next flight, it's a splashdown. We're not trying to recover it with the helicopter, but you splash down. ### Most Challenging Aspects of the Parachute System **Interviewer:** After getting the booster through the atmosphere, which you said is the hard part, as far as just the parachute systems, what do you think is the most challenging part? **Peter Beck:** It's always the drogue deployments because that's where the loads are at the highest. Getting the drogue out in a really controlled manner—for us, we have quite long riser lines for the drogue because we need to get the drogue far enough out behind the stage that we're not in the wake of the flow field. It's actually quite hard to get those riser lines all sequenced nicely without pulling big shock loads. If you do that wrong, you can end up with two to three times your shock load force straightaway, and you can design structures to carry four times the load easily. Just ripping out attachment points and mounting points and things like that becomes problematic. That's probably pretty tricky, and then the deployment of the main is the next highest shock load event—making sure you get that deployed safely and nicely. All while maintaining the correct angle of attack, because if the vehicle underneath it is at a 45-degree angle of attack as opposed to the chute, when you go and deploy a main and it snaps around, then once again you just spike your load cases right through the roof. It's really about controlling that load and that load path through the openings and the various mechanisms. That's the thing I love about parachute systems so much—it's beautiful in the way that this is all passive. Apart from some reefing cutters and things like that, it's basically all passive. If you look at your deployment bag, it's got a shear cutter and a tag line to the pilot chute. When the pilot chute starts to strip off the deployment bag as it inflates, it all just happens passively like this—it's all mechanical sequencing, very elegant. **Interviewer:** That's a great way to put it. I always say that there's a beauty to the deployment of parachutes, and I think reefing line cutters are probably one of the most underrated parts—most people don't know about them. ### Ram Air Chute Design **Interviewer:** I noticed in your latest videos that you've gone with the ram air chute design as opposed to the ring parachute. What's the method behind that madness? Why choose that? **Peter Beck:** When we're trying to capture with a helicopter, it's all about maintaining as much hang time as possible. Ram air provides aerodynamic lift force as opposed to just a parachute, which is drag. You're able to have a much smaller piece of fabric stowed and achieve lower descent rates for the size and mass of fabric. Also, generally, they directionally will steer into the wind, so it kind of sets up a nice platform to go and recover from. That was evidenced by our drop test where we dropped them, and they needed to go and ultimately turn into the wind and just settle down and provide a nice stable platform and easy to hook from. For our first recovery system test with parachutes, we won't use a ram air; we'll use a more traditional circular parachute or an elliptical parachute. We're focused on building a super robust parachute system just to give us a splashdown first, because we need to go and pick up the rocket after it's splashed down and review what we've actually got before we go any further. So we've gone for slightly more traditional techniques for the very first parachute recovery. **Interviewer:** Will the booster control the ram air at all, or is it just passive? **Peter Beck:** No, it'll just be passive. **Interviewer:** I love the simplicity of passive. The more you have to control, the more problems that you have to solve. Just let the helicopter pilots take care of the rest, right? **Peter Beck:** Yep, you got it. ### Recovery Timeline and Attempts **Interviewer:** When can we expect the first official recovery attempt? I know you guys have a lot of testing to do yet. **Peter Beck:** It depends on what you want to classify as official, I guess. Flight 17 is our first baseline, and the first recovery we're going to try and actually slow the vehicle under parachutes enough to splash down safely, which we'll go and pick up the stage and recover. So flight 17, later in this year, Q3 this year, will be where we attempt to actually fully recover a vehicle, go and pick it back up, and stick it back in the factory. For me, that's the biggest milestone we need to achieve. We've sort of knocked off all the other milestones, and once we have it back in the factory, then we really can understand where we're at. Up until then, we've got the telemetry on the stage, but until you actually get it back, it's really hard to work out how much of it's going to require a refurbish. ### Closing Thoughts on Parachute Technology **Interviewer:** Is there anything else you would like to add or share with the viewers? **Peter Beck:** I just think there are a lot of comments about parachute systems: "We did this, we went to the moon, and we did this back in the sixties. How come we're still doing this? Surely this is something we shouldn't be having any problems with anymore—parachute systems should be easy by now." I'd just reiterate the fact that there's analysis and design that will take you to a certain point, but it's still very much a black art. It's also hypersensitive to small tweaks and changes. Just moving a tag line somewhere or a cable somewhere can have quite a large effect on the performance and reliability of the system. I'm really actually super excited you're doing this because I think recovery systems are one of the most underrated or underexposed technologies within the space industry. They are immensely difficult and immensely niche. If I reflect back to our sounding rocket days when we were launching suborbital sounding rockets, we would always try and recover payload sections and boosters from them. I remember in the first five vehicles that we flew, they were just like core samples falling out of the sky. They were trailing fabric behind them without us scratching our heads about why that ripped that parachute out. The loads that you can generate from that little piece of fabric are just phenomenal, and the way you stage those systems and deploy them is just unbelievably critical. **Interviewer:** Thank you so much for doing this for me. I really do appreciate it. I tell everyone, if I could pick one country to go to visit, I would love to pick New Zealand—not only because it's a beautiful country, but you have Rocket Lab there. You can have a beautiful background and watch something awesome go down, or up I guess. Do you guys have like a viewing area for people like me to stand and watch? **Peter Beck:** Not really. Unfortunately, the launch site's a private site and it's really remote. Honestly though, the better view is on the live stream, because although you're at the pad, you get to see the first ten seconds and then you run inside to watch the live stream anyway. **Interviewer:** I won't take up any more of your time, Mr. Beck, but again I really appreciate this. Thank you so much, and good luck to you and your endeavors in the future. I'm pulling for you guys. **Peter Beck:** Thanks, I appreciate it.