Boom Supersonic's SuperPower Jet Engine Is Real! Transcript, AI Summary & Key Points

00:04 Hello, it's Scott Manley here. A couple of years ago, I got to visit Boom Supersonic when they were operating the XB1 out of Mojave. I even got to fly their simulator down there. I didn't, however, get to see a supersonic flight of this test aircraft. Now, that was extraordinarily cool that they were able to build this thing and fly it. But Boom's ultimate goal is to build a full-size airliner which can cross the world at supersonic speeds carrying passengers.

00:30 And anyone in aviation will tell you this is an extraordinarily hard goal. Obviously, we have Concord, an example of an aircraft which was successfully built. It performed this task and it was ultimately never successful because it couldn't fly many of the routes. partly because sonic booms were banned over the US, but mostly because the general public at large wanted cheap jet travel, not fast jet travel.

00:57 Regular subsonic jets were fast enough for them. And uh so Concord became something that was only ever flown by people with ridiculous amounts of money and not enough time, the kind of people who could justify the extra cost. It is a technological tragedy that in the 1980s we were able to fly around the world faster than the speed of sound as passengers and in the 21st century that is no longer possible.

01:21 And I would really like it to be fixed. But yes, there are lots of people who know a lot about aircraft who will tell you that this thing is impossible not because of the laws of physics but simply because the economics do not support it. And critics will point out that Boom worked with uh all the major jet engine manufacturers to try to find an engine which would be would be able to operate on a supersonic passenger liner.

01:46 And ultimately none of them were willing to sign on for the project. And so Boom have decided to start doing it on their own. And this on the face of it may seem like folly. If you look, there are only a handful of jet engine manufacturers in the world that can compete for passenger airlines. In particular, China has been able to build their own jet airliners, but they still buy engines from Western manufacturers because they can't compete in terms of efficiency.

02:15 But late last year, Boom made an announcement of a new strategy for their engine. One which will actually help them with their whole cash flow. After all, it takes a lot of money to design and build a supersonic airliner. And so, when I was in Denver a couple of weeks ago, I made a point of heading over to their factory in Centennial to have a look at what they're building and why they think this is going to be the next big thing.

02:40 >> So, where are we now? >> Where are we now? Yes. >> Where are we now? >> We are in the Boom Supersonic R&D Super Center. Uh, so this is uh >> and this is Blake, by the way. >> Hi. Blake who basically runs them, right? >> Uh I I I >> You took the impossible quest and you've been sticking with it, which I find endearing and wonderful. >> Well, thank you.

03:00 Uh if if stay the game long enough that eventually eventually you might win. >> Yes. >> Uh but no. Yeah. So, I'm founder CEO at Boom. And uh my my job is that we make supersonic flight mainstream. >> Yeah. >> And that we have to explain to kids one day that it took six hours to cross the country and seven hours to cross the Atlantic. And the kids go, "I can't believe anybody did that."

03:22 >> Right. Yeah. I mean, we're trying to recover the great future of the 1980s. >> Yes. >> Right. Where you could cross the Atlantic in a few hours. >> Yes. The problem was it was for royalty and rock stars, right? Like everybody wants faster flights so long as they're safe, comfortable, and affordable. Concord zero out of three. But there's no reason you can't do three out of three.

03:45 >> Yes. Exactly. Well, you know, this is this is your concept, right? This is the overture. This is your model, right? >> Oh, we have the Air Force One one. >> Uh, yes. Uh, so that there is one of those in the Oval Office, by the way. >> Yes. >> Um, so >> more realistically, we have United. [laughter] >> There's But we can go back on that one. But the in all serious, so United, American, Japan Airlines are all partners.

04:06 They all have airplanes in order pre-order. The concept. So, see, think Concord. $20,000 a ticket for a seat you might have thought was Ryan Air and an airplane you couldn't really in a very cramped airplane that you didn't completely trust. Yeah. >> And this will be certified to modern safety standards. It will be profitable for United. Very profitable actually at what the people already pay in business class.

04:29 So if you think about like a 787 Dreamliner or an A350 wins big long haul airplanes, they got the nice seats up front. >> 20% of seats about 80% of the money y >> is is in that front cabin. Ultimately we want to do supersonic for the rest of us. But what we're starting with is basically taking that front part of the Boeing airplane, chopping it off, making it to its own jet, and making it go fast.

04:50 So, this is 64 seats uh in a very nice premium configuration. And if you can afford to fly fly business class, you can afford to fly supersonic. >> See, technically, I could afford to fly business class, but it doesn't get me there any faster. >> Right. So, so I think there are people today who look at business class and they're like, "This is luxury, and I can't justify it.

05:10 It's a waste of money." Right. >> Right. But being there early, >> yes, then that's actually valuable. And you, you know, so you think about it, more meetings in a day, uh, more nights with loved ones, like imagine you can leave the East Coast in the morning, uh, do a late afternoon meeting, take a client to dinner, get on an airplane, and be back in time to take your kids into bed.

05:30 >> Yeah. >> Right. Like, this is a time machine. Like, that's the one thing we can't get more of. And the other thing I think is really interesting about supersonic is um I think most trips that people take on supersonic will be trips they otherwise would not have taken at all. Yeah. This was true of the of jets when Hawaii was 16 hours on a flying boat.

05:50 Nobody went >> because they couldn't afford the time. Forget the money, the time. All right. And then it was the jet that made Hawaii a tourist destination. It was a jet that enabled the Beatles to take the first world tour in 1964. They could not have done it earlier. And it is the supersonic jet that will let you go to Sydney when you might have gone to Honolulu.

06:09 So, so, uh, those of you who have been following Boom know that we built and flew the XV1 as our test airplane. That's the first supersonic jet made outside of the government. The first civil supersonic jet since Concord and the first to show. Yeah, that is a very early wind tunnel model. >> I saw an even earlier model in the museum. The >> Oh, yeah.

06:25 That actually that museum and this are both off the exact same geometry, >> right? Uh so this this is what we thought it would be like when we didn't know what we were doing. >> Yeah. >> And uh it just looks wrong now. >> Um [laughter] we >> we put a lot of work into it. >> We put a lot of work into but this is so one of the principles is you have to speed up iteration in the digital world and speed up iteration in the physical world.

06:46 We got to make hardware development more like software. So we took this into a wind tunnel to gather not because we thought we had the airplane right but because we had to get the calibration data so that we could iterate digitally. So we came back, we came back with a bunch of data and then we iterated, iterated, iterated, iterated digitally. Then 12 months later, we tested this airplane.

07:04 >> And this one has like an intake on the top is one of the main things. >> This is and and this shaping is different. The wing geometry is different. The tail got bigger like this. This is a very different airplane 12 months later with lots of digital iteration. And it's almost exactly the airplane that we built and flew. So if we go down to the end, this is the final wind tunnel model.

07:23 Uh my chief of staff, John Banani, besides being a a world-class chief of staff, is also a world-class model maker. He didn't make the wind tunnel model, but he did paint it up. Yeah. >> Uh and so this is this is almost exactly what we flew. Um sorry, this is exactly what we flew. It's a very small Delta black one. That's right. And if we go around the corner, you can see it again.

07:45 There is nothing in the world like flight testing an airplane that you built. It is the most thrilling thing you could possibly ever do. And uh I can't wait to get back into that in just a few years. So this is the XP1. This I this will be I think remembered by history as the airplane that made supersonic flight legal again. We had a ban on supersonic flight from 1973 until June 6th of last year.

08:07 Uh after six demonstrations on the XP1, uh the president signed an executive order uh legalizing supersonic flight again. Uh, a bill is making its way through Congress to turn that executive order into law. Yeah. By the way, it got through the House unanimously, and it just got out of the Senate Commerce Committee unanimously. Everybody wants faster flights so long as there's no sonic boom, >> right?

08:30 So, it's like supersonic is legal, but sonic booms still have to be limited. >> Yeah. I mean, that's what the the rule always should have been. We what we should have banned bad noises. Instead, we banned speed. And I think the the consequences of that are deep and farreaching. I think we're having an absolute renaissance in aviation. I think this is like the roaring 20s how it will be remembered in history of like when we started clearing the dumb roadblocks that held us back and we started innovating again.

08:58 And I I am just super super thrilled to be part of that. So one of the fascinating things about this airplane is it was done by just 50 people who refused to give up when uh when you know mere mortals might have thrown the towel in many times. A few people did quit, >> but those who those who saw it through, their names are on the on the airplane after we landed.

09:20 The team that did it >> signed the airplane. >> Yeah, this is one of a kind. You had to all like you cut the sheet metal and bend it and rivet it all, you know. >> Yeah. Well, not very small amounts of sheet metal, a lot more carbon fiber composite. >> Okay. >> Uh everything white is carbon fiber composite. >> Okay. >> The people that did this put blood, sweat, and tears.

09:38 Fortunately, only a small amount of blood. Uh but lots of sweat and lots of tears went into making this happen. >> It did get a bit of blood sacrifice here and there >> a little bit. We we had actually no major mishaps, >> right? >> Uh uh that I'm very proud of the safety culture that we we built. So there are no OSHA reportables, but uh we had some near misses.

09:57 >> I mean, you wanted to sacrifice jet fuel. That was an important part. Yeah, you needed to do that. >> Yeah, you got to convert jet fuel into human progress. That's that's the name of the game. >> I know. >> Yeah. >> Look at this. >> Is that Isn't that just beautiful? >> Absolutely beautiful. >> Yeah. Yeah. I mean, these were not the biggest engines, but you know, you have three of them.

10:13 [laughter] >> That's really what it is. >> So, so actually speaking of engine size, so this entire airplane >> weighs 12,000 lb empty. >> One engine for the production airplane weighs 14,000 lb. >> One Symphfony turboan uh engine is heavier than an entire XP1 jet. >> That's a lot of engine. I mean, a lot of that mass is just going to be in that core, right?

10:39 To solve the heavy dense materials in there, right? >> There's a lot of a lot of spinning metal. Um, and you know, like a 6 in another sorry, 6 foot diameter fan. The diameter uh of a symphony engine is bigger than the diameter of the fuselage of this airplane. >> And you know, that's a big deal that you are going on your own making those engines, right?

10:59 >> Yes. People called us crazy. I've come to believe that the insane thing was outsourcing it. Uh, like I cannot believe that I spent six years of my life trying to get like a hundred-year-old British company to go build a custom supersonic jet engine for a startup. Like why did I think that was ever going to work? And like think about the SpaceX story.

11:17 Can you imagine SpaceX had uh Elon gone to Aerogjet, they would have like studied it for 5 years and then said maybe we'll let you have a space shuttle engine if you ask nicely. Right. It just never would have existed. >> Well, he you he never made the most efficient engine, but he didn't have to, right? They just needed to make the cheapest engine.

11:36 >> Well, they needed to make one. Yeah. I mean, space SpaceX I think you have to understand is they entered into a market that was a commodity market. Like if you get the thing on orbit like mission accomplished, everything is the same. It doesn't matter if the rocket is pretty or nice or whatnot. If you can get it there reliably and cost effectively, you win.

11:52 It's a commodity business. >> Yeah. >> Yeah. But you know with the jet travel, so much technology goes into making those engines as efficient as possible >> for subsonic aircraft. >> That's right. >> You're not playing in the same, you know, field. >> So a lot of the design parameters change, right? So for a subsonic airplane, we want a lot of bypass.

12:11 You want a big fan. So it's going to take a big scoop of air and kind of kiss it backwards. Uh supersonic, a big fan is very draggy. You're super sensitive to the cross-section area of the airplane. So smaller is better, right? And so by the way, you go too small and now you sound like an F22. And those of us who are airplane nerds love it. The airport is not so much.

12:32 So So, so Symphony, that's what we call our engine for overture. Is kind of a Goldilocks engine. It's got a fan big enough to be quiet and friendly to airport communities. Small enough to go Mach 1.7 efficiently, and then some of the compression that would normally happen in the engine itself happens in the intake instead. Yeah. >> So it's got less compression stages.

12:50 Um, and it's got more of the high temperature technology when you're going, you know, going 30,000 ft. >> Your air's coming into the engine a lot hotter. >> Yeah, that's right. It's like literally you're talking minus50 versus plus 160. >> Yeah. >> So, it's a completely different thermal regime, so you need way more of the hot stuff. >> Yeah. >> And uh uh so anyhow, the uh in this building, we were building the first Symphfony engine.

13:12 >> I've seen some pictures of the core. >> Pictures. Yes. The building that we're standing in here is not one that exists at any other engine company. Uh Most of today's engine companies are heavily outsourced. Actually, all of them are. They've got like one mom and pop supplier to build one kind of part and then maybe they put it all together in the end.

13:31 And we said, look, we got to be able to iterate quickly, which means when we need to change a part, we need to go make it quickly ourselves. So, we're actually going to start from raw materials and go to completed engines and we're going to do it in one building. And that's what this building is. So we put a lot of energy into iteration in the world of bits and iteration in the world of atoms.

13:49 So all digital manufacturing and uh state-of-the-art digital design that lets you iterate rapidly across disciplines. We can talk a lot more about how we do that by mixing software and hardware is the key. Okay. So everything we're looking at here is kind of raw material that will be converted into into engine. >> So this is coming in from a supplier.

14:12 These big are forged and >> yeah, this is uh some of these are forged. Some of them are cast. Some of them this little one here is actually the fanciest one of them all. That's a bumaloid. Boom. >> Boomaloy. This is uh this is powder metal. This this is this will um be machined down into a high-pressure turbine rotor that has the highest thermal stress of anything in the engine.

14:37 And this is this is a very exotic alloy. Uh, and we have um uh we managed to get some of it uh to our spec and in another building we actually have 150,000 lbs on that stuff. >> Wow. Is it is that's powder then 3D uh is >> No, no, no. This is it's So what you're trying to do is get a nickel super alloy. >> Yeah. >> Uh with very uniform um uh metallurgy all throughout.

15:01 So you actually you actually atomize the constituent metals, mix them together uh in this like fancy atomizer machine. There are only a couple companies that actually know how to do this, but they basically we give them the recipe and they do it. Uh and then and then if you melt it, you actually can't melt it. Uh because that will cause like the heavier elements like settle segate.

15:22 >> Yeah, you need to do this in zero G. >> Uh well, that that would be the one way to make it even more expensive. But no, you actually use a process called isoothermal uh forging. >> Uh wherein it just enough that it bonds >> it bonds together, right? So it's not 3D printed. This this will be machined. >> I see. >> Uh it'll be either you know EDM cut or machine or maybe some combination of both.

15:42 But this turns into an HPT rotor. >> Wow. >> Um >> which of course is going to be getting most of the heat of the engine. That's why >> in fact it's the hottest part of the engine. So So if it's a jet engine sucks. >> It's a high pressure tur HPT highress turbine. >> High pressure turbine. Right. So you're taking in air that's probably already hot. Uh you're compressing it and when you compress air you're taking a a large volume of air and turning to a small volume.

16:06 So all the heat energy, all the thermal energy that was a big volume is now in a small volume. So it gets hotter. >> And then what do you do? You burn some gas in it and make it even hotter. >> That's right. >> And so then then the the the high-pressure turbine that the HPT. So this is the hottest part of the engine. It is hotter than Starship on re-entry.

16:24 >> Um it is hotter than the melting point of the metal that the turbine blades are made out of. This is like how insane this stuff is. Uh so that's the hottest part of the engine. And it would, you know, the and the that energy it gets consumed by the turbine to turn the shaft that then powers the compressor. That's how it that's how a jet engine >> that's how jet engine works.

16:42 >> That's how a jet engine works. Okay. Uh all right. So we're going to go in the R&D machine shop. So this is uh this is kind of one cell of engine manufacturer. We've got I think seven machines in here. Okay. >> And we are building at a secret undisclosed location a factory a building three times the size of this building with 10 times as many machines.

17:01 And again, what we're doing here is going from this kind of raw form materials down to the completed parts. Uh, this is called a turnmill. This machine weighs 64,000 lbs. >> I believe it. >> It sits on a on a concrete reinforced foundation that goes 4 ft deep that's vibrationally isolated uh from uh uh from the rest of the building. So, you got to be able to get these parts within about 1 thou tolerance in many places.

17:25 So, the machines vibrate. They can't shake each other or you'll be out of tolerance. Uh but this this we used to make like basically engine cases. Uh you can see there's one case up there. Now this machine will then flip around. This turntable flips. There's other side of it that's working. And this is kind of the the load unload side. >> This is turntable in here.

17:42 >> Uh yeah. Yeah. So this not only does this thing turn as it's getting machined. This entire thing flips around and there's a working section on the other side of the machine. >> Yeah. >> Ah on the forklift over there. Let's go catch up to that for the He's actually carrying the last thing we made on that machine, >> which just got finished. >> Uh >> this is a You can tell we didn't plan this.

18:05 >> That's okay. >> Uh but we're just we're just walking into like the most interesting stuff. Yeah, this is the uh this is the turbine center exhaust frame. >> It says in a forklift. Going have to be careful. >> All right, let's looks like he's ready to move. >> That's a wrecking ball. Hey, how's it going, man? >> Pretty good. How about you? >> Good.

18:20 Can we take a a picture real quick? >> Oh, sure. >> All right. So, this is the uh Symphony high-pressure turbine uh exhaust frame. This is m This is a cast Incanel. Yeah. >> It started out as about a 5,000 lb donut and we removed about 40% of it. This thing weighs about 3,000 lb. >> Yeah. >> Uh and uh and so this is uh it looks like this is headed over to the other side of the building where we're going to do some assembly.

18:46 >> I like how this is just like rolling through your snack area. [laughter] So yeah, it's it's all a factory. It's all it's all good. >> Yeah. Well, I guess we are nuts. Um, [laughter] so this can do a bunch of things, including it can do air foils. Uh, so >> so you're doing these these are your blades. >> Yeah, those are our blades. So this this is what it looks like as raw material.

19:07 We end up with this. We're starting with this bar stock. This is uh I don't know, Scott, did you go to the gym this morning? I'm [laughter] >> careful. The edges are in fact sharp. There we go. All right. workout for the day. So, this is 174 PH stainless. Um, this is how it starts. This is how it finishes. This is a lot easier to lift. >> So, to to give you a sense of like what's going on.

19:31 So, we start with this. >> Yeah. >> We rough machine kind of rapidly. Uh, then we then we heat treat to for stress relief, then come back and then we do final machining. >> And, uh, this is a stage one variable guide vein. >> Yep. So this sits uh behind the first stage compressor between it and the second stage y uh and actually pivots on its axis to change the airflow angle uh depending on the settings of the engine.

19:58 >> This is this is a stage two vein. How do you know stage one versus stage two? Well, that's a compressor. This one's bigger. [laughter] It gets smaller as it gets like the simple stuff. And then this is a a stator vein. >> Uh it's in the dock on the engine, I believe. >> Yeah. >> Uh so so all this stuff is getting made. We're we've made almost all the parts for the first engine, but we we can currently assemble and manufacture.

20:19 So, uh if we head to the other side of the building, yeah, we can we can see uh we can see some of the progress actually putting the engine together. >> And and let's be clear, how many parts of how many of these blades are in each of these? There's it's lots >> 60ish per engine. >> Yeah. >> Plus, you know, you got to these are all you perfectly turned parts or they would be if it wasn't a bad part.

20:42 But >> that's right. Yeah. You got to get them all perfect. >> That's right. >> And they all going to match up and they all work together. >> There's roughly a 1,000 of an inch profile tolerance on this leading edge. You know, this one's interesting to look at. Um that that that curvature looks wrong, but is actually correct. >> I mean, it's because you've got, you know, as your radial position in the engine, you've got different flow characteristics, different pressure.

21:05 So, you got to account for that. >> That's right. But also, you have to design the part to work at different conditions. Yeah. Yeah. And many times what you'll find is there's what's called an ondesign condition. So ones for us is like running at full power at Mach 1.7. Off design is takeoff where you're partial power and there all kinds of transients in between.

21:22 Yeah. And what you might if you only design for on condition, what you'll find is off condition is either very inefficient or sometimes doesn't work at all. >> Right. You got to make sacrifices at the peak to get uh the the performance across a wide enough range to do the job. >> That's that's exactly right. And that's and that's part of why the engineering gets complicated.

21:40 It's also part of why having great digital simulation tools is so incredibly valuable here. So as an example, the team uh so classically if you're designing blades in an engine, uh you need like four teams. One team takes uh geometry specifications and and CADs them up, creates them in CAD. And by geometry specifications I mean like how tall is the blade?

22:01 How thick is the blade? What is the curve of the lead edge of the blade? Um uh what's the twist of the air foil? What is the air foil? Yeah. >> And you and then you can turn that into 3D geometry. And then there's another team. So by the way, when these blades run, right, the engine's hot and there's thermal expansion. So So you have to aerodynamically design them for the hot shape.

22:22 We don't manufacture the hot shape. You manufacture the cold shape. Yeah. >> Right. So you have to do a hot to cold and a cold to high. That's another team. And then you got an aerodynamics aerodynamics analysis and you got to have a structures analys. So like four teams and you you end up with like >> and they all have slightly different requirements.

22:39 >> Slightly different requirements. >> They're going to fight things. They're going to have to compromise. Right. >> That's right. And what tends to happen is an aerodynamicist like optimizing themselves. They throw the design over the wall of the structures guys who then say that won't work at all. Yeah. And then and then change it then throw it back.

22:52 And then this iteration process takes months and it takes a gigantic team. Yeah. >> So, we built this thing called Bladeunner, >> okay? >> Which lets one engineer do the whole thing in real time. And I can I'll send you Scott, I'll send you some B-roll of this thing, right? Okay. Sure. >> But literally, it could drag a slider of like air foil curvature.

23:10 You can see the geometry change in real time because we have our own CAD kernel that actually creates the geometry. And then also in real time, it runs to hot to cold, cold to hot. We can do arrow and we can do structural simulations all in real time. So you can drag a a slider for a design parameter and you can start to see a multimodal analysis of how the structure performs on and off design.

23:34 >> So what used to take a very large team many months can now be done by one engineer in real time >> and he can just slide things around until he thinks he's satisfied enough people. >> Well, I mean he is the people. He is the Right. Right. because like what you end up with is like an engineer that can think about arrow and structures versus having these having these siloed different disciplines.

23:53 Yeah. like once you've done the analysis like and you got something called a Campbell plot for example that will show you where your uh resonance modes are. Yeah. And you don't want them to couple. >> So you can drag it around and make sure the resonance modes don't couple, right? And then you can look at the aerrow efficiency and how compression you're going to actually get and how that's going to be on and off design and what kind of stall margin you have.

24:10 And where we're headed is basically all of the engineering that used to be done by hand on spreadsheets. And the spreadsheets were like baby software. They're like not real software but they're like effectively they're software. Yeah. Yeah. So what we do is we put one software engineer on every hardware team and and the software guy his job is to help people get out of spreadsheets and into code.

24:30 And of course now with with with AI coding it's even easier to do this. The software guys set the framework up. The hardware guys contribute their engineering knowledge uh into the codebase with AI assist. >> Yep. And then verify those right as well. Very important. >> That's right. Which all these spreadsheets are typically not well QAed. >> Right.

24:48 and uh and and and so what we do is we set up everything should be done repeatably so it should be done automatically and you can you can accelerate. So that's the digital side. But then in the manufacturing side, you always been you always learn something to make real hardware about manufacturability, about performance. When you put Harvard together, you definitely learn something.

25:06 There's always a surprise. So how quickly can you get from a digital design to a completed part? Our goal is by the end of this year, we will be able to go 24 hours from a design idea to a part in someone's hand. >> Wow. Okay. >> Yeah. Uh let's go over to the let's go over to the engine. >> Okay. So, so, uh, the first because iteration is the name of the game.

25:25 The we are not building a completed symphfony engine first. We're building just the high-pressure core. Then we'll run just the high-pressure system and then we'll build then we'll iterate it and then we'll run the fully integrated twin spool machine. >> So, you're going to wrap this in your pressure system to feed it on one side and to take out the gas on the other side.

25:45 That's right. You're going to have another turbine sitting in front of it or something. >> No. No. Uh, you can do it with a big bellmouth nozzle. Uh but what you what you need is a variable exhaust nozzle on the back end to control the back pressure back pressure. >> Yeah. >> So actually if you look to your right that is the mounting frame for the variable exhaust nozzle.

26:00 >> Okay. >> So this gives you some idea of just how this is only the highpressure spool just for testing. >> Just just for testing. This is the only the high-pressure spool but it's freaking gigantic. This is like a four and a half foot diameter. Yeah. >> Uh exhaust nozzle. Uh and and there'll be some turkey feathers on here. It'll open up back and forth.

26:17 It'll look beautiful. It'll look like a >> fin. Oh yeah. It'll look great. >> And so I want to step away for a second because even your big plane fans may not understand the concept of the high pressure and the low pressure turbines. Modern jet engines typically have multiple spinning sections that spin at different rates. And the most common design is a two spool engine where you have a shaft that has the low pressure compressor and the low pressure turbine on it.

26:43 And then in the middle on separate bearings that run on that shaft, you have the high pressure rotor. And that will have a set of compressors at the front that will take the compressed air from the low pressure section. Then there will be the combuster section that actually burns the fuel. Then you'll have the high pressure turbines that handle the hottest and most energetic gases.

27:01 And then it leaves the high-pressure section into the low pressure section with the low pressure uh turbines. And the low pressure turbines, they actually generate most of the power in the engine because those are typically connected via the shaft to the large fan disc at the front of the engine that provides most of the air flow and therefore most of the thrust.

27:21 And so in the name of iteration, what Boom is doing is focusing on the high pressure section only. They're going to run that. That means they need to push in higher pressure air at one end and they need to reduce the pressure drop at the far end so that they get the conditions that will exist when it's integrated into a full engine. And this will of course let them iterate on that, find the problems while of course simultaneously working on building lower pressure sections so that they can create an entire engine.

27:51 The reason why modern jet engines have multiple sections is that as the air moves through the engine, it changes speed. It changes temperature and pressure. And the ideal rotation speed for the uh your compressors and the turbines changes. And so by having two separate sections, you can keep most of the compressor and turbine blades, you know, nearer to their ideal speed for performance.

28:15 >> Okay. And so uh and over here uh what we have is the now fully assembled high-pressure rotor uh for um uh for the first symphony high school. And uh and so this actually looked better a couple time. Yeah. Cuz it was hanging out. >> It was hanging out, right? But now we put these engine cases on it and you can't see under the stator in and stuff to make it work, right?

28:37 >> Uh yeah. Yeah. Small details. I mean, we're already building engines. >> Uh so so the uh so that is has uh been balanced already. The balance on this thing is insane. If the center of gravity on that rotor is off by one millionth of an inch, the engine is out of spec. And so a a lot of companies end up like outsourcing the balancing. So like ship it to a balancer, then come back and try and fix it.

29:03 Uh and we knew we need we knew we need to iterate this in multiple levels. So that's the engine and that's the balancing machine. It's like right there. And sure enough, it wasn't balanced the first time. The first time we put it together, it's like, "Oh dear, we wanted to make a shaft." We actually made something banana-shaped. So, we had to take it apart, rotate it 180 degrees, put it back together, and then we could balance that.

29:23 >> Okay. >> And that took that took like maybe 10 days. And had we had had we outsourced some of that, it could have taken a couple months, right? So, being able to like go here here back and forth in real time is um massively uh uh massively important. So, let's go take a a closer look. >> Sure. >> Okay. Backpack left behind before I cross the line.

29:46 >> Great. All right. All right. Well, welcome. >> Oh my god, it feels special now. >> Do you guys know each other? >> Hi. >> Eager, manager, manufacturing engineering. >> Hi, Scott Manley, individual on the internet or something. [laughter] >> Yeah, I don't know what to say. Right. >> So, I'm going to say a few words about what we're looking at here and then if you don't mind, Matt, I'm going to hand the mic to you and you can like say a little bit more.

30:05 >> So, so the let's orient you. So, remember jet engine suck, squeeze, bang, blow. We're going to pull air in, squeeze it, burn fuel in it, and then pull energy out of it on the way back. Yeah. >> So, so what we're looking at on top here is the front of the at the that is the front of the compressor. So, like we were saying before, big blades, you know, you're at the front of the engine.

30:24 Small blades, you're at the back of the engine. Yeah. And this uh this engine has six stages of uh compression. So, we can see the first. >> So, we can only see the first three, I guess, cuz that's the top of the third one. >> Stater. So, so blisk one here, bladed disc, blisk two, and these are these are sters here. Blisk three hanging. >> Yeah. Yeah.

30:43 That's what I thought would go in between these, right? >> Thank you for setting me straight there. >> Certainly. >> And then we've got So, we've got more hidden down in there. >> Yeah. Yep. Three more stages married in there. >> Yeah. >> Yeah. I don't want to even breathe on this thing. It's just funny is cuz it's going to consume air at a ridiculous rate.

30:58 And here's me holding my breath in case I push it off balance. [laughter] >> It's locked down solid. So, the the way you actually get to this point, you start with the rotor build. Okay. >> So, the very first part is this stub shaft here. And actually, we built this whole thing 180 from the orientation it's in right now on the big build plate you see behind you.

31:14 Okay, so you start with the stub shaft. That is the first part of that central rotative assembly. Eventually, that's where all the bearings will get installed onto. And then you basically just start stacking parts on top of it after that. So each one of these parts, this is the forward drive arm, blisk one, one, two spacer, blisk two, and then blist three down there, and so on so forth.

31:35 >> Yeah. What you do, you take them, you put them in the oven. We've got a really big oven over there. Uh my favorite story about it, to make sure it was working, we baked cookies in it first. >> Oh, at the right exactly the right temperature. >> Exactly the right temperature. Yep. Validated with thermalouples all over because we were also doing a temperature map.

31:50 >> In any case, you throw it in the oven, get it hot. Um the interference between these parts or the tolerances between them is so tight that going on cold, you would have to have a ridiculous amount of force to get them together. >> Yeah. Yeah. >> So, what you want to do is you want to get one part hot so it grows, moves clearance, and then you can just set it on with hand force, and then use a hydraulic ram to send it home and make sure it's actually where it wants to be.

32:13 >> And so, one by one, you heat these parts up, put them on, apply hydraulic force to compress it. >> Uh, and then you just keep stacking them. Once you've got all the blisks stacked up, that's when you put the tiebolt in. So, the tieb is the uh central bolt that compresses this whole thing. This whole thing is there's a bolt down the middle that's holding all this together or I mean the the interference fit is what's holding it together, but that's making sure it's like compressed to the right tension or whatever,

32:40 right? >> Yep. So the the interference fit gets you your initial position, but to >> to tolerate all possible operating conditions. You also have to preload this whole thing together. >> So calling it a bolt is a bit generous. It doesn't look like a bolt. It looks like a big threaded tube. >> But you have a big ass torque wrench to make sure it hits the right.

32:57 >> You actually couldn't even do it with torque. You've got to hydraulically stretch the bolt >> to a known preload value and then you just run the nut on by hand and then release the hydraulic pressure and that's how you get the preload. >> Interesting. >> Wow. >> The the force value we're going up to here is 150,000 lbs of preload. >> That's pretty no kidding.

33:16 >> And you keep saying blisk and for the people out there, I'm guessing blisk is blade disc. It's blade disc, >> right? you in the old engines you would have the uh the blades would go on individually to the disc. Here you're just machining like one big part. >> Correct. And that has presumably advantages in terms of assembling, you know, fewer parts.

33:37 >> Yep. Obviously reducing part count. Um it's great for efficiency for the engine as well. Every single one of those blades, no matter how small the gap is, there's some gap between them. >> Yeah. >> Um which can cause leakages and other things which impacts efficiency. >> The best gap is no gap. The best gap is >> and you also you also get uh weight advantages >> strong weight advantages and because this is an aerodyivative engine >> doing it with blisks was the obvious choice to get learnings on this engine for the

34:05 future Symphfony engine. >> Yeah. >> But so after you get that and you pull the tiebt real tight then HPT goes on and we can actually go take a look at the high pressure turbine now. >> So this is the high pressure turbine. Okay. >> Yep. This is the high pressure turbine. Got it covered for dust here. Yep. And so we have much smaller blades on this.

34:24 And these are the ones with the higher temperature material, I guess. So this isn't a blisk, >> correct? This would be a bladed disc. >> Okay. >> Um, so this whole assembly, you've got the transition shaft down there, which is what actually bolts to the high pressure compressor side. There's a flange buried in there. >> Uh, as you come back, you get to the HPT disc itself.

34:44 >> Uh, really highly stressed part, very high temperature. Super awesome. >> Yeah. Um, and this is upside down relative to that. Correct. >> Correct. >> Yeah. >> Uh, so the air is flowing this way through it. >> Correct. Right. >> And then these are high pressure turbine blades. These are actually 3D printed for the test engine. >> How long are they going to last?

35:04 >> Uh, >> long enough. Long enough. >> We the test engine we we the goal is to validate the aerodynamics and to learn 100% of what you have to learn to put together an engine and make it work. >> Sure. And then you can go for lifetime. >> Yeah. So I think we sized for something like 500 hours of run time. >> Probably we won't even do all that >> as we'll learn everything.

35:22 We like XP1 we size for 500 hours of run time. We didn't fly anywhere close to that. We'd get everything done. >> Yeah. >> Uh but uh but you know for production these will be investment cast single crystal. >> Okay. And again investment cast for each individual blade. You're still going to be doing individual blades for this. >> That's right. Yeah. Yeah.

35:39 There's a um it would be awesome if you could do a single crystal >> blisk. >> Someone might figure it out one day. >> The geometry doesn't really work that well. >> It would be it would be tricky for sure. Um >> but it could be done. >> It's not impossible. >> Physics does not preclude it. >> Physics does not preclude a lot of things indeed. Um, and if you take a look at these, you can see uh all of these little holes cooling holes in.

36:11 Yep. >> Cooling holes for course. It's hotter than the melting point. So, you blow hot air. You blow air through it. And you say cool air, but it's actually hot enough to burn. >> Oh, yes. >> Yeah. Lots of things. >> But it's cool enough to not melt this. >> Yep. >> Yeah. >> And inside of the blade, there's all kinds of channels printed in here for that cooling air to get distributed.

36:34 Yeah. Uh through all those cooling holes >> 100%. >> That's That's really cool. That >> So that'll be going on at some point. >> It's actually already been on. >> Okay. >> So you build up the whole high pressure compressor, >> preload it, put the high pressure turbine on, and then you've got to balance it. >> Oh, right. >> In that configuration, that machine, >> which is got the machine right there.

36:56 Um, so went through, balanced the entire rotor, break it back apart, install the forward split cases, which is where we're at right now. >> So that's the that'll contain the sters around the outside, right? >> Correct. >> Yep. >> So that's what's got all the sters. Uh, we're actually installing the variable veins, the inlet guy veins on the front side.

37:13 Right. Now, >> let's look at the combuster. >> Yes. So this is goes between those two parts, right? This is where you're actually blowing in you're throwing putting in the gas, the the fuel. And we are looking at this in >> So the the air flows around the outside of this or >> Nope. >> Oh, okay. >> So, okay. Ah, I see. Okay. >> Yep. So, we got flood covers on here right now.

37:34 >> Good idea. >> Just when you think about how much compression happens in the engine. Think about how tall those first stage blades were. Yep. >> All of that air gets squeezed out of this area. >> Yep. Yep. That's the compression for you. So, it all shrinks down to there. Inside of here, there's a number of combuster liners. >> Yep. basically big round parts with a ton of holes in it.

37:54 Uh >> are these probes I'm seeing in here? These Yep. Yeah. So, uh those are all rakes, pressure probes, temperature probes, >> uh to gather the data to calibrate our models when we actually take this to test. >> Mhm. >> Uh and then around the OD here, this is where the fuel nozzles themselves insert. >> Okay. So nozzles come in there. They go into the inner liners.

38:17 Fuel gets injected there. Combustion happens. Flows to high pressure turbine. Yep. So this is what uh all the sters that are buried in there look like. They're all individual blades. Uh these are all machined by boom. >> Mhm. >> Uh and these just come slotted in basically through a dovetail profile. You bring them in. You can see some of the instrumented versions of them here.

38:38 Yeah. Yeah. Have these keel heads, these pressure taps >> to capture more data during test. But then the first two stages here, the first ones are inlet guide veins, >> right? So those will adjust the geometry of the flow to, you know, allow you to have a wider operating range, right? >> Right. >> Uh and then blisk one goes there and then our S2s or stage two variables to give even more uh breath to our operating condition.

39:02 >> Yep. >> And then bliss two goes there and bliss 3 will go down there. >> Yeah. And these are like uh pool poles I guess for sensors. >> Yep. Exactly. Uh so we've got proximity probes, blade tip timing probes, uh pressure probes, all embedded into these cases as well. >> It's like measuring every blade as it passes by one of those things. >> Yeah.

39:23 >> There there are about a thousand individual signals that will be measured. >> Uh and uh we we actually have an in-house telemetry system that we built for that. Uh it captures all that data. It powers a real-time control room like you' use in flight test. Yeah. >> So if you need to say, "Hey, knock it off." like like we don't like what we're seeing.

39:41 You can press the emergency stop button and then all the data gets saved in a database. They can extract to the engineers tools so they can go query that data, do their analysis, do their post-processing with every every sample that was gathered and tested. >> So these variable veins are fresh out of the machine shop. >> Dude, do we do we have a complete ship set now?

40:00 >> Half set. >> Half set. Okay. >> Okay. So we need for half a case tomorrow. >> Um so this is one of the inlet guide veins. These just there's a bushing and other parts that install here, but basically you can envision these dropping in just like this. >> And then they're constrained on the inside by a clam shell. >> Yep. >> Um, so we're getting ready to install all these, get them rigged up, and then this case will go around there.

40:24 uh put onto the >> inlet transition frame up front. Put the bearing on. Take that whole assembly, flip it upside down, stack the combuster on top of it, stack the eye pressure turbine on top of it, throw the exhaust case on and give it to test. >> Put in the the ignition the the fuel inlets and stuff. >> Yep. >> Yep. >> And then you got an engineish.

40:47 >> And we got an engine. >> You ready to make some noise? And ultimately, of course, the engine is planned to do more than make noise. But one of the big things that happened in the last 9 months or so was a plan to use the engine to make more than just thrust. They are now planning to use these engines to generate electrical power. It turns out that Boom managed to get a fair amount of venture capital from Silicon Valley venture capitalists who also are heavily involved in the AI business, which is currently facing a

41:19 power crunch. And so it's completely understandable that those investors looking at the long runway it takes to get to supersonic flight might look at these gas turbines in the short term as being a way for the company to perhaps give them some return on their investment and potentially demonstrate to the market that the company is not entirely beholden to the FAA approving their aircraft.

41:42 Now, as someone that is interested in the prospect of a supersonic airliner, the idea of using these jet engines to power data centers is well deeply unsexy and uninteresting. But to the people that invest money in this, this makes total sense and I can see why this is happening. I'm hearing right now that there is a 5year lead time if you want to get gas turbines derived from currently existing aviation engines.

42:09 Boom. think they can get their superpower gas turbine running in about 2 years. And even if they end up taking twice as long, that's still technically beating the likes of GE by a whole year. Furthermore, Boom's turbine engineers uh argue that their design is actually more adaptable to power production compared to the large bypass turbo fans which are being built by GE and Rolls-Royce, etc.

42:37 Furthermore, developing a gas turbine which is designed to be used on the ground is clearly a lot simpler than designing one that has to fly on an aircraft. It doesn't need to have the same strict mass margins or extreme safety factor. And then of course once you have these things operating on the ground, you're getting experience with the turbine sections.

42:56 You're understanding their limitations and you're adapting and improving what will ultimately become the engine that is used in the aircraft. So, in an ideal world, Superpower gets to market quickly and makes a whole bunch of sales. And those sales in turn help fund the development of the airliner, which is what, of course, every kid wants. Now, speaking of what kids want, I wanted to fly their overture simulator.

43:22 I'd previously had a go on it when it was in San Francisco and managed a fairly respectable landing score on my one and only attempt. I only had about 2 minutes on this thing. Unfortunately, it was not to be. One of the big displays had been covered by a couple of error boxes which were related to interfacing with XPlane. And while I could see a bunch of the avionics and poke away at that, we couldn't unfortunately make a video.

43:47 So, uh, I'll have to wait leave that for some other time, maybe I'll come back in town and I'll get some special time on it to, you know, really push the limits of the system. What I did get to look at on the final part of the tour was the cabin mockup where, you know, Blake basically gets to explain his vision of what it would be like to be a passenger on this.

44:07 Now, understand that the company is really focused on the engine right now. There's not that many people working on the aircraft itself, but they still need something that they can sell to potential investors. You know, the vision of what it would be like to travel supersonic. So, one of our design philosophies, uh, not only doing our own engine, we're also doing our own airplane interior.

44:29 And, uh, I think you got to design the passenger experience together with the airplane itself. >> Yeah. >> It's about great. Like, uh, years before I started Boom, I used to get on airplanes and think, man, what if this airplane had been designed by like Steve Jobs and Johnny IV, >> right? Yeah. and and then you start to notice all these things that aren't great.

44:47 And uh the attention to detail that's not there, the care that's not there, and uh in building a new airliner, we we have a shot to to do it differently. >> Uh where the the passenger experience and the airplane itself were developed together. >> So my the best results you get when you've got designers that think like engineers and engineers that think like designers.

45:08 And so if you look at the this is a mockup of the overture fuselage. Yeah. So what you can notice here is this is a very unusual shape, right? It's not a straight tube. >> It is not a straight tube. This is called area rolling. Yep. For high mark things, right? >> Yeah. So for for supersonic airplanes, if you taper the a fuselage, you get a lot less drag.

45:26 >> If you taper it where the wings go out, that's really you maintain the average cross-section area. >> That that is what the theory says. Roughly. >> Yeah. The theory is not quite correct, actually. >> It's not quite it's a it was a rule rather than a law. >> Yeah. Yeah. Um we could go down a different rat hole about supersonic aerodynamics. Yes. >> Which I think is actually not well understood.

45:45 >> Oh no. >> But um but uh but that's a different conversation. So at any rate so we we we uh we what we've done is iterate physically and digitally. And this is not the final uh this is not the final geometry but let's actually step on the other side where the door is. >> Uh we probably I think we can still make some major improvements uh versus what we have here.

46:09 Um, but so this is where we would step on board. Now, if you've ever been on a Concord, the first thing you know is you have to duck [laughter] to get on the airplane. Uh, so this boarding door is 10 in taller than a Concord door and one inch taller than a 737 door. So if you are 95th percentile North American male, you can get on the airplane without getting a haircut.

46:31 >> Oh, that works for me. >> Yes. >> I can't afford to lose any hair. Uh and so the again if you contrast with Concord, uh this is incredibly spacious, right? And so we we're walking into the the front cabin here, >> right? >> And um Scott, I'm going to ask you not to take pictures of the stuff on the left because that's a little bit secret. >> Okay.

46:49 Point. >> So So there is a wonderful interior in here. Yes. >> Uh which which we're still refining, which is still a little bit of a trade secret. >> Okay. >> Uh but it's going to be uh it's going to be great. And so the uh the one thing I can say is there are no middle seats. Uh what we're trying to do is think about what are the things that people all hate about flying and see if we can fix as many of them as possible.

47:12 >> Closed windows. >> Closed windows. Right. Yeah. If actually every seat is an ejection seat and if you close the window it just fires you out of the airplane. Um [laughter] >> uh no but one thing we So what do people hate about flying? Middle seats. >> Seats that like if you recline you bother the passenger behind you, >> right? So every seat on over being bouldered by the passenger in front.

47:36 It's this zero game. So, every seat is in a shell. You can recline without bothering anybody, >> right? So, guilt-free recline. Uh, no middle seats. The other thing is the windows are never lined up correctly. So, we actually changed the frame spacing on the airplane. >> Okay. >> Such it is one half. So, this normally it's 24 in frames. These are 20in frames.

47:57 Why? Because the seat pitch is 40. And now the windows h and the seats will line up every time always. And in fact you get two windows per seat and one of them is positioned and we offset the so there's the window seat there's some other seats and and there are offsets such that every passenger kind of have has a natural window view that's in the right place for the average eyline.

48:23 >> Like we sweat this stuff like crazy. Um, there are only 64 seats and what we're optimizing for is to be able to get everybody on in 5 minutes and everybody off in 5 minutes. >> So, you save time in the air, you save time in the ground as well. >> And then you just got to work with the security people so we can get there 10 minutes before the flight.

48:41 >> Yeah. I mean, what what I'd like to do is a curb curb to flight guarantee. >> Yeah. >> And we we'll need some cooperation from the airlines and to do this, but um but when you're only doing 60 passengers at a time, you could do things you can't do, >> you know, for thousands of passengers. Oh yeah. >> So imagine if you had a guarantee if you're at the at the curb 20 minutes before departure, you're guaranteed to make your flight.

49:01 >> Yeah. >> Right. Then you don't have to get to the airport 2 hours early. So you save all that time, right? And then and then boarding. Boarding is 5 minutes. Offboarding could be really fast. How do we do instant bag check? We're working on all this stuff. There are things you can do. There are things you can't do on a Boeing or Airbus. Yeah. But you can do if you're designing the airplane from scratch and you're thinking again about what does everybody hate and how do we turn as many of those things into moments of

49:24 delight as possible. >> I mean, well, you can make a much faster flight by saving in so many places and it's not just flying fast. >> That's right. That's exactly right. You know, save, you know, save, you know, think about across the Atlantic, save three and a half hours in the air, save another hour and a half on the ground, and it just makes the whole thing much more worth it.

49:43 >> Okay, now we're at the back of the airplane. So this is notice how much smaller this is where we were standing before, but this is still the cross-section of like a Gulfream 650 or a Global Express. >> Sure. >> So So the worst row in overture >> is like the best private jet. [laughter] >> Um and and I can tell you back here the layout is one in one.

50:05 >> So there's these seats will be cans. We have to use our imagination a little bit. >> This will be your first class maybe. >> First first class is actually in the back. So you get on first, you go all the way to the back. No one's back here except the first class passengers. >> Yeah. Okay. >> Right. So you got privacy. The labs are actually forward so you don't you don't have um >> and you know they can board first and not have the plebs in business class walking by them.

50:26 >> That's actually right. [laughter] >> Yes. Uh and we I wanted to do a separate like exit but the wing is in the way. >> Right. >> So uh so there's you know some pesky geometry challenges. Probably some of this is still going to change. It's not all locked down yet. I mean your basic geometry of your airframe is probably pretty getting locked in. No.

50:46 >> Uh so so we didn't talk about this yet, but we are actually shipping the engine without the rest of the airplane first as its own product for power generation, >> right? >> So so that's where like 90% of the company is right now on the engine >> which will go first for the ground application. People talk about aerodyn converted for ground. This is ironic to be a reverse.

51:10 to make a land derivative aero engine. >> Land derivative aero engine. >> Uh but but in the meantime, we we have while while we're not full speed ahead on the airplane right this moment, >> uh we have a small opportunity to look at every design decision that we thought we'd finalize and say, could we do it a little bit better? >> Right. >> So that's what's going on right now.

51:26 So I I think we're going to do one more pass on this >> and this geometry. >> Yeah. To give to give you an example of something that probably will change. And my intent in sharing this is that you know who knows where this is going to actually go but it gives you it hopefully it gives the the your audience an insight for just how we think um airplanes today should be hospitality experiences but nobody realizes it right and so that what we should think about is like the best experience you can have in a restaurant or or

51:54 a hotel and but yet so think about airplanes relative outlets you don't go into a great restaurant through the kitchen unless you're in an action movie. Why do we board airplanes through the kitchen? Why is the boarding door at the front of the airplane? That's a dumb place to put the boarding door. What you should do is put the boarding door as far back as you can.

52:14 Ideally, halfway back because then you could board through it and board the front cabin and the back cabin in parallel, right? So, we're probably going to move the boarding door and I really don't want it in the kitchen because that's just weird. >> Sure. >> Anyhow, so next time you visit Scott, maybe we'll have a little bit more to show. Uh uh but again that that principle is just like start I mean we're all passengers and we all we all want to build the airplane that we will love to fly on not just once but over and

52:40 over again. So just how many of those things that are classic terrible things about flying can we actually convert into moments of joy? >> Yeah. >> All right. >> That's the I think that's about all we've got >> that that's that's all we got. That's a you've given me a lot I'm going to say. I didn't expect to see quite so much about the engine. I'm disappointed I never got to fly this thing.

52:58 Oh, well >> denied one more time. >> Look, this is a vision. >> The may we're secretly breaking something every time you visit because that's how we get back. >> Come back. Yeah. >> Yeah. We're actually a drug dealer, not a not an airplane company. >> But no, look, as I've said before, you we know this is an incredibly hard thing to do, right? And I am with you all the way.

53:19 I'm so happy you're still doing this >> and I'm going to be excited to see a symphony actually firing up, making noise. >> It's going to be a hell of an experience. I don't I I don't think it'll be quite as good as watching XB1 fly. >> No. >> Uh uh it will be the second most amazing thing we built. Uh and then we'll get back and build uh build an airplane.

53:36 And uh uh it's just um I I think for a lot of us that have been at this for a while, uh you know, there have been high days and there have been low days. Uh but the high days make it worth it. >> Yeah. >> Actually, I'll tell a story that your your audience might love. So, my my youngest daughter is now four and a half >> and uh from when she was very little, you know, I'm just enough of a nerd.

53:57 I'd go watch Rocket videos with her. Okay. And so, you know, and I would tell her how awesome it was. And, you know, at some point she's like, "Daddy, red car rocket." I'm like, "Red car rocket?" Uh, I don't know what that is. And I was like, "Maybe she wants to uh uh wants to watch like a F1 or something." She said, "No, no, no, no. Red car rocket."

54:14 And eventually I realized that's what she the Falcon Heavy Tesla launch with the red Tesla. Tesla. Yeah. >> And so then she gets a little bit older. She's maybe two and a half and we we go to launch an SDS model rocket and I'm, you know, I'm the guy that I am. So I get the smallest rocket. I put the big D motors in it >> and we you know, she presses the button and that thing goes and ends up >> and it tears off its parachute.

54:36 >> I mean, it ends up in a tree field over. Yeah. Right. And she's super upset. And at first I thought she was upset because the the we lost the rocket. >> But she was actually upset because she didn't know why it didn't come back to the pad. >> Oh. >> Right. And I had to, you know, so our kids were growing up in in a world where rockets coming back and landing and be reusable as normal when we have to explain to them that there was a whole age where that wasn't that was not possible.

55:00 >> They would just disappear over the horizon. You'd never see them again, >> right? And no one would even think about that being something that you could change and and and subsonic aviation needs to go the way of the disposable rocket. Yeah. >> Well, except for people that like flying subsonic, you low and slow. But yes, I know subsonic. I know. Getting there slowly has to stop being >> That's right.

55:20 I I I I'm not saying we should ban the Piper Cob. >> No. No. >> Um >> All right, Scott. Pleasure as always. >> It's been been fantastic. So, again, thanks to the team at Boom and Blake especially for letting me in, showing me around, and sharing the dream, if you will, because supersonic passenger airliners are very much the thing of dreams. They were dreams that were made reality in the past and they faced off against hard economic realities and unfortunately lost.

55:48 They failed. They became memories, things of the past and frankly they should be things of the future. And so it would be nice to see the development of symphony succeed even although it's not in the aerospace application because yeah ultimately it will be a requirement for overture to be brought into reality as an airliner. I'm Scott Manley. Fly safe. >> [music] [music]