In this episode, CEO Kyle Clark of BETA Technologies walks us through the details of how to design, build, and operate electric planes — first for relatively short light-cargo flights, but eventually, he says, for all of aviation. I loved this conversation so much.
Text transcript:
David Roberts
As Volts listeners know, the list of “hard to abate” sectors of the economy is rapidly shrinking. Just in the last few years, new pathways have opened up to decarbonizing steel, concrete, recycling, large trucks, and more with clean electricity.
The one sector that almost everyone agrees will resist electrification is aviation.
But that may be changing too! In aviation, as in almost every other sector, electricity is already doing more than people thought possible even a few years ago. There are electric planes flying today — generally smaller planes, with few passengers, carrying very light cargo, but they exist. And there are legions of people working on expanding their capacity.
I thought I would check in with someone at the center of these developments, so I contacted Kyle Clark, the CEO of BETA Technologies. BETA has developed, tested, and is in the process of building two aircraft: one is a small plane and one is an EVTOL (an “electric vertical take-off and landing” vehicle), which is basically a plane with small helicopter rotors on it that allow it to take off and land like a helicopter. The company is starting by targeting small cargo flights but has plans to expand into passenger flights and beyond.
I don’t say this often, but I feel like I didn’t get enough time with Clark. There was so much to cover! The whole discussion turned out to be fascinating and hopeful and I came away far more bullish about electric aviation than I expected. I hope you enjoy it as much as I did.
All right then, with no further ado, Kyle Clark of BETA Technologies. Welcome to Volts. Thanks so much for coming.
Kyle Clark
Thanks for having me, sir.
David Roberts
I have been curious about electricity and planes for a long time, and I'm excited to dig in, but maybe let's just start with what is BETA? What are you making there and why, of all the things you could do with your life in the world, did you go here?
Kyle Clark
All right, so starting with, what is BETA? BETA is an electric aerospace company where we have focused on decarbonizing aviation in a kind of stepwise fashion, from doing electric propulsion with batteries and small aircraft, and leaning forward into larger, longer range, and more capable aircraft across time. So, we focused on the core technologies of building motors, inverters, batteries, and we've incorporated them into airframes. And we just entered production of making multiple airframes for customers. So, that's BETA as a company. So, why are we here or what are we trying to accomplish? We have a goal of decarbonizing aviation.
And we take this pragmatic approach, like I said a second ago, with this market entry strategy that isn't trying to leapfrog right to urban air mobility or right to regional transport. It starts with cargo, medical logistics, moves into passenger, moves into longer and longer range.
David Roberts
Do you have an aerospace background? What were you doing before this?
Kyle Clark
I have an aerospace background in the sense that I have always been intrigued and passionate about flying. Unfortunately, the school I went to didn't have an aerospace degree offering, and I was compromising between playing hockey at high levels and doing aerospace engineering. So, I ended up at Harvard and I did the closest thing that I could to aerospace, which was material science. But for my senior project, I, of course, did BETA Air, which was the predecessor to BETA Technologies.
David Roberts
Uh-huh, ah. Straight into this, then. All right, so you've got two planes — is planes the generic word for them, or do I have to say EVTOL? Is that how you pronounce the other one?
Kyle Clark
Well, "airplanes" define something that flies by a lifting surface like a wing, and "aircraft" encompasses everything. So helicopters, whatever. So the EVTOL is a type of aircraft and an airplane is something that we make as well. So we — it's an aircraft and airplane. Conventional takeoff and landing in the former, going runway to runway. And vertical take-off and landing in the latter, going helipad to helipad.
David Roberts
Right. So, the former is just a small plane. The second one — I feel like I want to encourage listeners, this is an audio medium, but I feel like I want to encourage listeners to go look at the video because it's a little bit difficult to describe — it looks like a small plane, basically, with four helicopter rotors plopped down on top of it. So, it takes off and lands like a helicopter, but in flight, it performs like an airplane. Is that — is there a word for that hybrid, or is that something that you have sort of invented here?
Kyle Clark
So, a lot of folks have gravitated towards this concept of being able to take off and land vertically and fly like an airplane.
David Roberts
Right.
Kyle Clark
And this has been embodied in aircraft that have tilting rotors, aircraft that have tilting wings. What we chose to do is what you described. And if you imagine a little drone or quadcopter with an airplane overlaid on top of it, the way that it works is it takes off like a quadcopter drone, vertically, gets to about 20ft in the air, and there's an additional propeller at the back of the airplane that starts pushing it forward through the air. As it moves forward through the air, the air over the wing starts to create more and more lift, and about 30 seconds later, you stop the rotors on the top that were the quadcopter, and you point them like javelins into the wind.
And at that point, you basically made a runway in the sky with those rotors. Then you start climbing like a regular airplane. Then you fly for a couple of hours, and when you're at your destination, be it a hospital, an urban center, or wherever you're going, you start to slow down. And before you stall the aircraft, aerodynamically stall it, you turn those top rotors on, and then you start slowing down, decelerating and descending at the same time, much like a helicopter does, making a runway in the sky in the landing. But you don't touch the wheels to the ground until you're stopped about a couple feet off the ground.
And then you lower it down vertically to touch down. And the magic of that is that you have the flexibility of going directly point to point. Let's say you're going to a base, to a hospital, to a cargo center. Wherever you're going, you can go point to point. But because you stopped the rotors and you flew like an airplane, you get to go the distance of an airplane, which has about four times less drag than a helicopter on average. And so you go four times as long for every unit of energy, which is, of course, really important when you have a limited amount of energy, like in a battery.
David Roberts
Right, right.
Am I wrong that the plane and the EVTOL, the electric vertical take-off and landing craft, look quite similar? Am I right in thinking that the EVTOL just is literally the plane you made with rotors on it? Like, the bodies look quite similar. Are they substantially structurally similar?
Kyle Clark
Your eye is telling you the truth. They are identical. And that's part of the magic of the science here, which is aircraft structures are sized for the worst loads they can encounter, whether it's turbulence, thunderstorms, landing loads, or crash loads. All of those loads are enveloped by the fixed-wing aircraft. So, if you're going really fast and pull the controls into a particular condition, you will create the max amount of stress on the airplane. A minor amount of stress happens when you lift it up by the fans or the four rotors on the top.
So, we actually use the exact same wing, fuselage, and tail for both aircraft. And the only difference is either you add the rotors, or you leave them off. From a certification standpoint, a production standpoint, a spare parts standpoint, and a pilot familiarization, it makes for a really consistent experience across all those domains.
David Roberts
Is that true on the inside too, in terms of operation and flying? Like, do the controls look the same? Is the training the same? Is there special —?
Kyle Clark
It's a great question. So, the way we've engineered the aircraft is such that there is control harmony or consistency between both modes of flight, because what you don't want to ask the pilot to do is to switch their brain from one kind of control setup and gain to another. So, if you pick up the airplane and start flying forward on the rotors, you're actually going to put the exact same inputs in that you would put if you were flying on the wing and push the nose down. And that harmony allows the pilot to seamlessly transition from vertical flight to wing-borne flight.
And I won't get into all the control theory behind it, but it is a major part of succeeding in piloted transition flying.
David Roberts
Interesting. The plane itself. Describe the plane. This is like, size-wise, it's like in the Cessna family, right? It looks like a two-seater.
Kyle Clark
No, it's about three times the size of what you'd consider like a Cessna 172.
David Roberts
Huh.
Kyle Clark
So, it's three times the size. Of course, that's in total mass. So, it's about 7000 pounds. Its wingspan — a Cessna is like a 34ft wingspan — if I remember correctly, our aircraft is a 50-foot wingspan. A Cessna is about 7ft tall. Ours is 14ft tall.
David Roberts
Got it.
Kyle Clark
So, in different dimensions, it's not quite twice the size if you were to look at any linear dimension. But in mass, it's about three times the size of a two-seat Cessna trainer. The inside of the aircraft has two pilot seats in the front. And then there's room for three industrial pallets, like those pallets that you see at Home Depot or whatever. There are three of those pallets, 51 inches high and then just under 4ft at the base. And they actually are designed to fit perfectly into the airplane for like UPS or FedEx or Amazon, to move three pallets at a time from a distribution center to wherever it needs to go.
David Roberts
And that's both the vehicles, since the bodies are the same size. So, was this designed, did you design it around cargo, sort of basically like a small cargo?
Kyle Clark
Yeah, absolutely. Actually, our very first customer was United Therapeutics, where the customer wanted to move organs and tissues and they specified a four-foot-wide cockpit, and that was so they could put two organ containment systems — these are like, you put a heart or a lung inside of a chamber, it has its own batteries, it has its own sustainment, and they get strapped down inside what would have been maybe a medical helicopter, but now it's our airplane. And as we evaluated the space, we said openly with this development partner, United Therapeutics, that we're going to design this also around a pallet.
And at that time, we got UPS to sign up as a customer, and they helped with the design. So, for example, the floor height off the ground is at their standard loading height. The width is for a standard industrial pallet. The radiuses on the door even allow for that pallet to move in freely the way that they wanted it to move in. So there's a lot of design choices. Aviation, aerospace engineering specifically, has little sense of humor for off-point design. Right. You've got to get it right. And that's why we put so much investment in the upfront engineering of the system.
That includes, how is it going to be used? The third portion of that is that, of course, we wanted to allow ourselves to put passengers in there, but we actually have a little extra room for a six-person airplane. So, we have a six-person airplane in the civil domain. If the military were to use it, they could put nine people in there.
David Roberts
This is the same plane we're talking about. You could fit nine people —
Kyle Clark
Exactly the same plane. In fact, the cargo tie-down rails are also spaced to hold seats.
David Roberts
Ah, why could the military hold more than normal people just because they're willing to put up?
Kyle Clark
Well, I mean, the aircraft can carry the right amount of mass to carry those people. But in the FAA, they have different demarcation points for certification levels. And this is a Part 23 Level 2 aircraft, and that only goes up to six people.
David Roberts
I see. The first obvious question is just how far will this plane go relative to a diesel-powered plane of similar size? I guess —
Kyle Clark
That's a great question.
David Roberts
or similar function, I guess, would be the better question?
Kyle Clark
So, we have flown our aircraft 336 nautical miles. So, that's 380 something statute miles on a single charge.
David Roberts
Huh. That's funny. That's roughly comparable to a really good electric car.
Kyle Clark
Yeah, and that's real-world point to point. When you fly a similar class of a turbine aircraft, it'll go 800 to 900 miles. So, call it roughly a third of the distance of a turbine-powered airplane. But we do that with an energy storage medium that's like one 30th of the energy density. But what you have to do then is you have to have really efficient power conversion from the stored energy to the propulsion, and a really slippery aircraft, and a low structural weight fraction, which means that you have a lot of room left to carry those batteries in terms of weight. And I can walk you through the math, but it's actually right on point of what Mother Nature would say from a physics standpoint, what we should get for range at the maximum maximorum of design.
David Roberts
Which is to say, it's unlikely that a plane of this size, powered by batteries, is going to go much further than that. I mean, are there hard limits?
Kyle Clark
There are some aerodynamic things that you can do that compromise its commercial viability. For example, if you doubled the wingspan, you could go further because your lift over drag ratio gets better. But the problem is, you can't put this aircraft into standard helipads at hospitals, and you wouldn't be able to put it into a regular parking spot for a caravan or something. The other thing is, when you want to certify an aircraft, you have to have a significant margin for everything. Lightning strike, turbulence, crash loads. So, you put a bunch of that stuff into it. And I'm going to answer that question slightly differently.
When you take the pilot or the humans out, you can get quite a bit more performance. So, it's not the physical limit, but it's a limit within the bounds of Mother Nature, level of technology, and the regulations.
David Roberts
Got it. Will the EVTOL go the same distance as the plane?
Kyle Clark
It'll go a little bit shorter. Yeah, you lose about 50-ish miles off the range today when you want to take off and land vertically for two reasons. One is you use a fair amount of power over a period of time, which uses a fair amount of energy for the takeoff and landing. So, you consume things at a much higher rate when you're hovering. But the second thing is, while you're flying, you have a little bit more drag. So even that, you know, 10-12 percent more drag will render a slightly shorter range on the aircraft.
David Roberts
50 miles doesn't seem like that big a penalty.
Kyle Clark
Well, it's interesting. It's a disproportionately large penalty because we always have to carry somewhere around an extra hundred miles in the airplane. So, if you have a range of 250 miles and you have to carry an extra 100 miles for reserves in case you get put on hold or whatever, then cutting 50 miles out of what's left can be 30% of your effective range.
David Roberts
Interesting. But that is presumably quite a bit farther than a normal helicopter can go. Am I right in thinking that?
Kyle Clark
It's about the same as a normal helicopter? I mean, there are some high-performance helicopters that go a little bit further, larger helicopters, but smaller helicopters are right in that range.
David Roberts
Interesting. So then, what's the advantage of the EVTOL versus a helicopter? Just more cargo?
Kyle Clark
So, more cargo, you carry more stuff. It is way cheaper to operate. The magic thing about aviation is that the recurrent cost of operation, contained within the fuel burn and the maintenance, dominates the cost of aviation.
David Roberts
Interesting.
Kyle Clark
It's not really even the cost of the airplane up front. So, for example, for a two-hour-long trip that we fly regularly in this airplane, we'll put $17 of electricity in the plane and go and fly for 2 hours. If you go fly a helicopter, it's really bad. But even if you fly a fixed-wing turbine aircraft, that's like $700 of fuel. So it's like a 40 to 1 delta, and the maintenance is like a third to a quarter. So it's a big benefit. The big benefit is you've rendered the recurring cost of operation, from an energy perspective, almost irrelevant, so that the total addressable market then changes very quickly and you learn to sweat the asset or use it often.
So, that's number one. The second one is that many, many of our customers actually do care about the sustainability of their fleets, and they recognize that aviation is disproportionately pollutive compared to ground-based transportation or rail or anything. So, if it costs less and it's significantly more sustainable — I'd love to riff on why it's so much more than ground-based changes — significantly more sustainable. You kind of hit the two biggest things for cargo carriers, medical carriers, and ultimately passenger carriers.
David Roberts
Are they more expensive upfront, is the ticket price higher than what you'd pay for a comparable plane or helicopter?
Kyle Clark
It's less than a helicopter, a little bit more than a plane. So, a typical plane of this class would be $2.5 to $3 million. This plane costs $3.5 to $4 million, and a helicopter will be $6 to $8 million. So, it's, you know, on the lower end of splitting the difference, but that recurrent cost of operation, because working aircraft, which is different than pleasure aircraft, working aircraft are asked to fly regularly, all day long.
David Roberts
Yeah, yeah.
Kyle Clark
And their amortization cost on a per flight hour is kind of de minimis in the overall cost of the operation.
David Roberts
So, I know that, you know, when you're talking about electricity, you obviously have much less energy density than liquid fuels. And you are much more conscious, I think, of weight and drag and all this kind of stuff, trying to make it work with a lower energy density source. How much, like if that plane, you said the plane will do like 380 miles, how much will it do with three pallets in it? Like, what is the penalty for once you start loading it up with cargo?
Kyle Clark
250. Once you load it up with cargo.
David Roberts
Huh.
Kyle Clark
So, that kind of record-setting flight, I'm 250 pounds myself, plus equipment, plus test instrumentation. So, I had about 600 pounds on the airplane when I flew that mission. And we flew a lot of missions around that range, but that's the one that kind of went the furthest.
David Roberts
Wait, which mission is this?
Kyle Clark
386 statute miles.
David Roberts
Oh, so that's a recorded thing. You actually went up and flew and —
Kyle Clark
Oh, yeah, yeah, no, so one thing I should also mention is that our industry of electric aviation has a lot of people who talk about future state. One of the things I pride our business on is only talking about stuff we've already done, like our production facilities and our missions for the Air Force, our missions with customers, the flights that we've flown. The whole tech industry here has a bit of a trust issue. And so, like, even in our pitch decks and stuff, we only show real photographs and real videos, never photo renderings, and never talk about future state stats.
David Roberts
Yeah, yeah. So, these two vehicles, these two aircraft you are currently building and selling them, or currently building, not yet selling, where are you on the actual market part of those?
Kyle Clark
So, we just opened our production facility in December, and we have our first production runs of these aircraft coming through that production facility now. Over the last two and a half years, three years, actually, we've been flying what we call "pre-production" prototypes. And these aircraft are representative of the production, but they were kind of built by hand. Right. They didn't have all the tooling and all the processes and all the FAA conformity. So, what we've used those tools for, those assets that we have now, those representations of the production assets, is to go and fly missions for charity under the, you know, the watchful eye of UPS, go fly customer pilots, go and fly with the military.
We just finished a four-month deployment with the Air Force, where they tested our aircraft across hundreds of sorties for different applications of moving water, medicine, moving MREs, moving chocks to different austere locations, and other such things. So, those assets really have proven to the market that this technology really works. All the while, we've been spooling up our production so that we can build these at rate.
David Roberts
Right. So, when's the first aircraft going to roll off the line?
Kyle Clark
I would say that it rolls off the line mid-quarter four of this year. And we have a whole sequence behind it. And again, like the first one, it goes very, very methodically and purposefully because it really defines the work instructions and all the inspection points. And there's a wave of aircraft that come behind that.
David Roberts
Presumably, you've got buyers.
Kyle Clark
Yeah, you asked about people buying these aircraft. So, we've taken a whole lot of orders. We have a phenomenal backlog of orders and those orders, some of them are with deposits, meaningful deposits. Then we have this massive qualified pipeline, like many, many billions of dollars of qualified pipeline. There's a lot of folks that are kind of looking at this industry and saying, "Will it really work? Will it really work for my mission?" And there are some real leaders that have stepped up and said, "I believe enough in sustainability. I've come and seen the demo flights." And they've leaned in and they've placed firm orders.
David Roberts
Tell me about the batteries. My assumption is, in an application like flight, everything is about energy density. So, you're maximizing energy density. So, what kind of batteries are you using, and are they off the shelf? Are you somehow involved in designing and building your own batteries?
Kyle Clark
Yeah, it's a great question. The first thing is energy density, or specific energy density, which is the first order parameter that you have to look at.
The second order is actually power density, because when you take off and land vertically, you're consuming power at a very high rate. And you have to have a battery that's capable of creating that current. The other is actually a big one. For us, it's cycle life and safety. So the economics of the plane can be very much driven by the cycle life of the battery. And of course, the volatility and the safety of the battery is paramount to anything that's going to be certified. So when we look at a battery, for example, we say it has to cross a threshold, a binary threshold of power capacity, so that it can sustain the highest power flight we expect it to perform at.
And then we take the maximum amount of energy density, and then we have to design an infrastructure around the battery to handle the worst-case thermal runaway for safety. And then the economic trait says, "How do you want to use the battery?" As you probably know, other people know that if you run your cell phone up to 100%, down to 0% every day, it'll last for a couple hundred cycles. If you say, "I'm going to charge it up to 95% and then down to like 25% or 30%," it'll last for a thousand plus cycles. It's a ten times difference in the cycle life, right?
So, what we do is we recognize that aviation — because we always have to carry that big reserve, like a hundred miles of reserve — we're never really going to beat up the batteries at the low states of charge where you're creating irreversible degradation. And then, if we manage the hot, high-temperature conditions through thermal management and ground-based charging, then we end up with cycle lives that are well north of a 1000, 2000 to 3000 cycles. And you get that kind of for free because the FAA demands that you carry that reserve all the time, so you're not beating up the battery.
David Roberts
How's that compare to the life of a, I don't know, a diesel engine in an or, you know what I mean? How long is the plane going to last?
Kyle Clark
So, our aircraft will last 35,000 to 40,000 hours. That means you're going to replace the batteries 10 to 20 times within the life of the airplane. Which, by the way, is about how often you change an engine on an airplane over the life of the airplane.
David Roberts
Interesting.
Kyle Clark
So, the batteries, they aren't wholly extracted and thrown out. The cells come out in modules and all of the protection mechanisms, the tubes that they go in, the battery balancing, the monitoring, the structure gets reused. And you take the modules out. And what I'm actually looking at over my shoulder right now is a battery energy storage system that goes next to grid-tied converters for charging the aircraft. And the way that works is you take the batteries out of the airplane, you put them on the grid, and they'll sit there for another decade providing arbitrage, frequency regulation, volt wire support.
David Roberts
So, after that — it's a little bit like second-use batteries for cars. Like, once they're not suitable for the cars anymore, they still have a lot of juice.
Kyle Clark
Right. But the cool thing here is that because we control the chargers and the aircraft, it's a standardized shape, form factor in performance, battery management, and all the communications. And it's really important because when you go to charge a working aircraft, you want to charge it really quickly, but you don't want to strain the grid. So for example, here we have a 250 kilowatt interconnection into the grid and we can charge over a megawatt because we have that arbitrage of batteries. So you can turn the aircraft very quickly if you load it up with packages or organs or something else.
But your grid interconnection, you know, most airports aren't set up to have a whole lot of electrical. They brought fuel here in the past.
David Roberts
That's going to be one of my questions: whether you're sort of straining the power at one of these things?
Kyle Clark
Yeah. And the answer is no, if you architect the power system correctly.
David Roberts
So, just to be clear, if I'm landing one of these and I want to charge it super quickly, I pull some power from the grid, but also some power from other batteries that are on site.
Kyle Clark
Yeah. In locations where the grid is constrained, that's exactly right.
David Roberts
Interesting. And what is the battery chemistry?
Kyle Clark
It's a lithium-ion manganese cobalt 6-6-6 style cell with a couple of other additives that allow it to be slightly higher energy density. The form factor of the cells is a 21700 in our case, and that's what we're certifying with. However, we've flown with all kinds of different chemistries and tested all kinds of different chemistries, whether they're N forms, prismatic pouch cells, different sizes of cylindrical cells. And there's a nice balance in the 21700 between the isolation capability of individual cells for thermal runaway purposes, the availability and the high quality of them, and a chemistry that allows you to get very, very high yield and high quality at the cell level, which rolls up to higher reliability at the pack level.
David Roberts
And that battery that you just described, is that something you can buy off the shelf, or is that something that will have to be custom designed for your purposes?
Kyle Clark
You couldn't buy off the shelf, but you could have them made much the way that we do. But in the FAA, you have to have conforming everything. And conforming means that they're produced to a standard drawing, and for every aircraft, they're exactly the same, and they meet our specifications. So we have a great relationship with our cell supplier, where those particular runs of cells go through an elevated level of quality checks, paperwork, and conformity inspections. And then when we receive them here in Vermont, we actually test every single cell for mechanical, electrical, physical properties and catalog them all before they go into a module and then a pack.
If you looked at it, you'd be like, "Oh, well, that looks a little bit like an automotive battery that was using cylindrical cells." But the fundamental difference is these are much more conformed in the eyes of the FAA, but they're also fully balanced, and there's way more sensors and monitoring. Here's a paradigm shift that I think a lot of people miss: when you create an electric vehicle on the ground, the default scenario of a fault is that you shut everything off and you glide to the side of the road.
David Roberts
Right. I'm trying to keep in mind that all this is about being way up high in the air. So, there's just a whole different level of safety consideration.
Kyle Clark
So, your safety analysis and your fault hazard criticality analysis actually result in something that is engineered upside down of many industrial or consumer products where the safe mechanism of failure is to have it fail on. So, if a sensor goes bad or a semiconductor switch latches, you could really have a bad day in an airplane, unless you were to architect the system to stay on and continue to perform its function even when the fault or the error has occurred. So, it's really neat to see folks from Tesla or from GE that come here, they start engineering an airplane, and you walk them through this analysis, and they're like, "Wow, this is upside down of everything I've ever engineered." But you have to do it that way to have this incredibly high level of safety that's expected of us by the FAA.
David Roberts
Yeah, yeah. Just out of curiosity, if, you know, whatever act of God, whatever the battery did go out, is the type of plane that you could glide — could you glide it down to a landing?
Kyle Clark
Yeah, absolutely. So, first of all, there are five batteries in the plane that are all individually configurable that can perform all the functions of the plane. So, the probability we have to push way out into the very, very improbable.
David Roberts
Right, right.
Kyle Clark
If you do, in fact, in test flights, a lot of times, 15 minutes before the end of the test flight, I'll just shut them all off, right? And I'll glide for 15 minutes because the aircraft has a very high lift over drag ratio and then land it normally. So, it's a phenomenal glider. But at the same time, even if you're a really good glider, if you're flying over Long Island Sound in the wintertime with your kids, you don't want to be a glider. So, you make the redundancy, you know, commensurate with the operations that you want to perform.
David Roberts
And a final question about batteries. Is there, I mean, do you have in your head the notion that there could be or can be or will be better batteries, more energy dense batteries? Like, is that a big piece of how you think about the future of the company, or are you sort of taking the performance of the battery you have as a kind of a fixed quantity and designing around it?
Kyle Clark
So, without question, it's the former of those two options, which is the batteries are constantly evolving, improving in energy density, lower impedance, which means less losses. And actually, the reliability and quality is going up at the same time with different additives and other things. So, is it fundamental to the financial closing of our business? No. And that was kind of one of the theses. The mission has to close with today's battery. It's not going to close every mission, but the mission has to be enough such that the UPSs and the others can actually do what they said they're going to do with it.
But the interesting thing is, every year that goes by, batteries improve their energy density by, let's say, 5% to 7%. That's compounding. That means every seven years it doubles the range of your aircraft.
David Roberts
That's wild.
Kyle Clark
If it doubles the range of aircraft, that's four times the connected cities — as it's the square of the radius to make the area coverage. It's actually a really fascinating paradigm that's never been seen in aviation before. Right. Because the best performing day of every aircraft you buy today is its first day, and it only goes down from there. Now it goes up. And we've already seen it in the short seven years that we've been at this company. We've gone up and up and up in range at a very high rate. And to answer the second part of your question, in our lab — we actually have an entire lab dedicated to battery development, safety, and high altitude operations and everything — we have batteries that are already two generations past what we're building right now.
David Roberts
And these would be in the same form factor, so you could slot them into existing planes?
Kyle Clark
You ask all good questions, man. So, at the bulk level, they're the same form factor. We have absolutely drop-in replacement cylindrical cells that just have a higher energy density. But we also have different form factors at the cell level that at the module level, they're identical.
David Roberts
Interesting. So, I could buy one of these and theoretically hope that its range increases over the lifetime of my ownership of it.
Kyle Clark
Well, not only theoretically, that's the commitment we make to the industry, and that is already in hand. And there are batteries we fly with for test that have significantly higher range and higher capacity than the ones that we're able to sell in a conforming, certifiable —
David Roberts
Interesting, because I guess the FAA is going to have to put its stamp of approval on every new generation of these? I'm guessing there's a —
Kyle Clark
You're absolutely right. Now, with the trust and the validated analytical tools and other things, then that burden to introduce new technology like in batteries, that's part of the kind of the engineering focus of our business, is to create not just a battery that's certifiable, but a process for continuous certification of delta batteries, whether it be the litany and the battery tests or the analytical work.
David Roberts
So, you're not doing everything from scratch every time.
Kyle Clark
Exactly.
David Roberts
Every time you — the other question, which now occurs to me again, as I hear you describe this, is, what about battery swapping? It sounds like if these come in and out really easily, why isn't that faster than a fast charge? Why not design around that?
Kyle Clark
So, I mean, when we're doing flight tests, high cadence flight test days, sometimes we'll swap batteries between flights. It takes 30 to 40 minutes to charge up the aircraft. By the time you take five batteries out and put them back in, you're 15 to 20 minutes in. And that, you know, may work well on a nice, sunny, dry day, but the reality is, in cargo operation, medical operations, the rain's coming in sideways, it's snowing, it's sleeting, you're in sandstorms. Whatever it is, it's not always the case that you want to be shoving big pallet jacks or robots underneath an airplane.
So what we found is that our customers are like, "Look, it's going to take us 30 to 40 minutes to unload the airplane and then reload it anyway. And because it can be charging the whole time, the cadence of operations actually is way lower burden and much higher cadence net, and a higher level of safety if we just recharge it."
David Roberts
So, 30 to 40 minutes, that's extraordinarily fast for the capacity of a battery.
Kyle Clark
But remember, you're only charging up 50% to 60% of the total capacity because you have to retain that reserve in the bottom end.
David Roberts
Right.
Kyle Clark
And you don't want to charge it up to 100%. Of course, you could. So, batteries are very nonlinear when they're in their CI, we call it constant current charge range. It can accept charge at a very high rate, like a C rate of three, two and a half. That's a 20 or 30 minutes charge is totally feasible. When you get up into the 90 plus percent state of charge, you have to reduce the current and go to a constant voltage charge, so you can consume as much time, like getting the last 5% or 8% of the battery charge as you do to get most of the battery charged.
David Roberts
So, going from like 30 to 80 or whatever is —
Kyle Clark
Yeah, or 90 or so. Yeah, exactly.
David Roberts
super fast. Let's talk briefly about light-weighting. I'm guessing, you know, using a much less power-dense source than your fossil fuel competitors, you've got light-weighting on the mind at all times. What sort of techniques have you used to make this thing light?
Kyle Clark
Yeah, so if you have a battery energy density like a cell of light, a normal number would be, let's say, 250 to 270 watt-hours per kilogram. So that's the level of technology you can get access to in this form. The light weighting really comes in and how do you hold it, how do you monitor it, how do you keep it safe in the event of a thermal runaway? And those are the things that erode the net energy density of the batteries. So how do we do that? Elegant engineering, simple engineering, materials science. So we'll use titanium, we'll use ceramic matrix composites, and we'll use very, very efficient structural load paths between the big mass of the battery and the frame of the aircraft.
So, those are all kind of basic engineering techniques.
David Roberts
So really, it's the battery itself then, and managing the battery itself, that is the bulk of the weight consideration here.
Kyle Clark
Yeah, I mean, if you have a 7000-pound aircraft, you can have 3000 pounds of batteries in it.
David Roberts
Wow.
Kyle Clark
And so, you have to make a really — I mean there's four dimensions here that give you your performance. The energy density of the battery, that's given. You have the lift over drag ratio of the aircraft, the propulsive efficiency, and I'll be back to that in a second, and the structural weight fraction. Our secret sauce here at BETA is that we have exceptionally high propulsive efficiency. And I'll just give you some numerics on that. So, if we have a 3000 pound battery and we're flying for 2 hours and we have a 98% versus 99% efficient motor, you might say, "Well, it's just 1%."
Like, well, hold on a second, it's actually double the efficiency. 98% to 99%, you have half the losses, right? That means you have half the cooling drag, and cooling drag can be 30% of a traditional aircraft. Say it's 5% of aircraft. So you could have 5%, give or take, of range by a very small difference in efficiency. But what's forgotten about is that that 1% of 3000 pounds, it's all of a sudden 30 pounds. So I'm burning off 30 pounds of batteries in waste as opposed to propulsive efficiency. So, having a very high propulsive efficiency, and by the way, I'm talking about 1%, we see motors that are 92% efficient versus our 99% efficient and you're like, "Wow, that's an eight times difference in drag and an eight times difference in wasted energy."
So, we are like myopically hyper-focused on the efficiency of the propulsion, and that includes the branch circuit protection, like fusing and cabling, as well as the inverter, which is a semiconductor-based system to convert DC to AC, and the electromagnetics, in this case, a permanent magnet motor. Those are the technologies that enable electric flight as much as the batteries do.
David Roberts
Interesting. And so, the body itself, is this some sort of fancy pants carbon composite or —?
Kyle Clark
We call it Fancy Pants. No, yeah, it's a carbon fiber composite structure with a whole bunch of different stiffening mechanisms, like cores, we call them, which is like a foam or a Nomex, that's in a structural, rigid form that creates — like, if you go over and pick up a piece of our airplane, you're like, "Oh, my God, you want me to sit on this? You want me to trust my life on this?" But this is where that no sense of humor in aerospace engineering, for poor engineering comes in. You have to get those right. And we have analytical tools that are validated and tested and validated and tested to say that these super lightweight structures, aka Fancy Pants composites, are actually just the right amount to handle all the loads that the aircraft can throw at it at all conditions.
That's the structural weight fraction part of the equation. And it's a really important part of this whole business in that we're trying to do something really hard. Like, the first thing we're trying to do is fly electrically. Then we're trying to fly vertical takeoff and landing. You have to be world class in all the things that enable that, like batteries, motors, inverters. But you also have to be world class in aerodynamics, structural weight fraction, and operational efficiencies that all affect the ability for this thing to do real work and make a meaningful dent on climate change ultimately.
David Roberts
I think anybody who's listening, who has driven an electric car, will have been struck by how peppy it feels relative to its gas competitors. Just the torque. I have, like a Chevy Bolt, the sort of low-end, econo-box version of an electric car. And it is faster off the line than anything I've ever driven in my life.
Kyle Clark
No, it's awesome.
David Roberts
I'm guessing in planes, you don't want to be doing a lot of... zipping I guess, but is there a comparable difference in performance of the plane? Like, is it more fun to —
Kyle Clark
Oh, yeah, a couple of things. First of all, the acceleration is much greater. You have that same thing of a very — you have a constant torque curve, so you don't have to wait for things to spin up. Instantaneously, you have maximum torque, so you accelerate down the runway very quickly, and then you get into a climb. And by the way, we chase our aircraft with other aircraft for test purposes often. And our aircraft, like, outclimbs Cessna Caravans, it outclimbs all kinds of small aircraft. Definitely outclimbs, like the Skylanes and the Skyhawks and all that.
David Roberts
Can you use a shorter runway because you have more, more torque?
Kyle Clark
Sometimes, it depends on the weight of the aircraft and the shortness of the runway also has to do with the speed of takeoff, not so much the climb rate. So, that's one. The second thing is, you don't have any engine noise.
David Roberts
Yeah.
Kyle Clark
So, that acceleration comes without that vibration and noise. You just have the prop going like a whoosh.
David Roberts
Right.
Kyle Clark
Which is a cool feeling. The other thing that electric motors do that we've never had the ability to do in piston or turbine engines, and the way that our electric motors are architected, it actually has two independent stators and two independent inverters. So, you size the motor such that if you lose half of one of the motors, you still can climb the aircraft. And so, that gives you, when everything's operating, this amazing amount of torque per weight. So, you outclimb all these respective engines that if they fail, they're just gone. In our motor, if half of it fails, you're still flying.
You're going to climb at a lesser rate, but you're still flying. Huge safety improvement, but also, to your point, you get that really peppy, sporty feel taking the thing off.
David Roberts
Like somebody's going to make a tiny little electric stunt plane for fun. For funsies, right? Has anyone done that yet? I mean, it seems like you could do a lot in that space, too, just of like stunt flying. Just fun flying.
Kyle Clark
Definitely. I mean, you could make the equivalent of the Roadster, and it's coming. There are a few little prototypes that people are blasting around doing. You know, one of the things that I mentioned before is, like, to really justify the investment in an electric airplane, you have to utilize the asset at a relatively high rate. In order to do that, you kind of corner yourself, at least at a market entry strategy, into industrial applications like organ delivery and cargo and high cadence passenger flights. So it will come. But right now, there is so much to go and solve these big industrial problems.
David Roberts
In terms of the pilot training, like, if I had a pilot's license and I knew how to fly a plane of roughly comparable size, what additional training would I need to fly one of these things?
Kyle Clark
So, in the fixed-wing variant, you would just come to normal comfort training. There would be no statutory requirement by the FAA to get additional pilot training that we know of to date.
David Roberts
Oh, interesting. So, I could just step into one of your planes and I would know roughly what to do.
Kyle Clark
Look, it would be a good idea, and your insurance company would probably say, "Go get some training." I mean, it's like right now, if you move from a Cessna 172 to a Lance Air Turbine or a TBM, two very different aircraft, but your pilot licensing requirements are the same. All you need is an instructor to say, "He can do high performance and they can do complex." There's no test ride, there's no anything.
David Roberts
Right.
Kyle Clark
But nobody does that. What they practically do is they go and get training, they get the endorsements, and many times, their insurance company will require, they'll have an instructor sign off. That's what we're talking about for the fixed wing. However, for the vertical takeoff and landing, there's an entirely new type rating that you have to get.
David Roberts
Yeah, that's a whole new animal. I mean, right. I would think that the training is bespoke for that thing?
Kyle Clark
Absolutely. Yeah. And it's still being kind of finalized, but the SFAR, the Special Federal Aviation Regulation that's coming out this fall, basically says that you have to get time in type, especially to fly commercial operations, something near 250 hours. What's interesting with the aircraft we've developed is we've put in side-by-side dual control seating for exactly that purpose. Actually, I don't think anybody else in the industry has done that. So we actually are now training other pilots to fly our aircraft. And they learn in the ALIA aircraft, and they may use that as their tool and stepping stone into this whole industry, which we're clearly excited about.
David Roberts
So you or somebody to get these EVTOLs into wide circulation are going to have to run some kind of training program, is that?
Kyle Clark
Absolutely, yeah. I mean, look, we run a couple of different training programs right now. We actually have a flight school internal to BETA with about 400 students in it, where we train every engineer, every employee here to fly if they'd like to. And many of them have aspirations of flying ALIA, and many of them have. We by far have the most pilots flying our electric airplanes of anybody in this AAM space. But we also have set the table to run a flight school.
David Roberts
Oh, interesting.
Kyle Clark
And we've done so by building simulators, a curriculum, learning management system, and all the necessary documents for people to learn to fly. And we've administered that to Air Force pilots that have flown our plane, to Army pilots that have flown our plane, to passenger pilots that have flown our planes. And we intend to do that in a commercial capacity as we kind of roll these things out.
David Roberts
All right, so I've been mired in the details here, but I did want to ask you some kind of bigger questions about, you know, the future of things. So I guess the first question is just, you've got these two models now that you are making, on the verge of making and selling, basically already sold. What is next? Are you going to just dial these in or is there another model, sort of fundamentally new model that you have on the horizon? What's next for BETA?
Kyle Clark
I think the short answer is yes. It would be naive to think that our first model of aircraft is our best. In fact, you always have to make rational business trades. As you evolve an aircraft or any product, you see all the goodness that you could shove into it. But you say, "You know what, I'm going to put that on this shelf over here called 'good ideas'." And you pull those down at some point in time. Now, some of those go into an iterative improvement of performance or cost of our existing models, which we definitely are already doing interestingly enough. Even like the first of a commodity. Like if we build our first wing or second wing or third wing, our fourth wing, we're already improving that production process and making tweaks to the design to make that easier, whether it be a kind of a vestigial tab to make it easier to hold or something complex like a material system. That's unquestionably happening. But it would also be really silly if we then said that that's the best implementation of a 7000 pound, six-passenger aircraft. What is clearly happening, and without giving any details, you know, we've designed and built batteries, flight control systems, motors, inverters, interiors, doors, latches, landing gear.
Those absolutely will be incorporated and more capable, larger, heavier payload, longer range aircraft. And we're not ready to talk about any of that right now. But it's a beautiful future. It is bright. There's so much goodness to be had and it's coming.
David Roberts
So, you're not going to tell us what the next model will be? I mean, because you could go for more cargo, you could go for more passengers, you could go for the same cargo, longer range. Like, there's —
Kyle Clark
You've nailed all the dimensions that we consider. And basically, we just, like with this aircraft, with United Therapeutics and UPS, have to do that in concert with a customer. And it also would be naive for us as aircraft developers to pretend to know more than we know. So, we've engaged customers to get that right. To get those ratios you just outlined, what do you need exactly?
David Roberts
You mentioned the charging system. So, you've also designed your own battery chargers. I saw a picture of them on the website. They look like a little cube to accommodate these planes and EVTOLs. What would an airport have to do? Just install some of these chargers? I mean, is it that simple?
Kyle Clark
Yes, effectively. I mean, at the first order, you install some chargers. And we've actually connected from here down to Arkansas, down to Florida. And we're putting tons of these chargers in, in partnership with customers. We put them on military bases. Those chargers, fundamentally, are the first order thing you need to have electric aircraft from every airport. For EVTOL, it's a little bit more complex because unless you're going to an existing helipad, you need some augmented landing areas. So you need takeoff and approach clearances, like, you know, trees and towers and wires managed. You need lighting systems.
And then, like the landing pad in front of me, we built our first prototype vertiport gear. It has a deck on it that has to be de-iced in the wintertime. Right. So, you're not, if it's windy out, you don't want to set the thing down and slide.
David Roberts
Right, right. Is that all the same for helicopters, or is it —?
Kyle Clark
Sort of. Typically, helicopters fly what we call visual flight rules, VFR. EVTOLs, at least our EVTOL, need to fly in all weather to bring organs and bring, you know, packages and stuff. So you have to consider that both in the aircraft design, but also in the landing area design. The other thing is the lighting system. Like, there are NVG (night vision goggle) compatible lighting systems that you put in here so that you have all time of day operations. And then the power system that goes into the vertiport is similar to the ground-based charging. But typically, if you have a limited amount of area, you want a higher cadence operation, so you put in a higher power charging system.
David Roberts
Interesting. So, a little bit more prep is required to use the EVTOLs. The aircraft you have and the capacities they have. Who are you selling them to? What are the first applications? You mentioned organ delivery, small cargo. Give us a sense of the range of things these things are being used for.
Kyle Clark
Yeah, right out of the gates, the military will use them for cargo and logistics. So that's really similar to a civil application. If they want to use water or medicine or humanitarian relief domestically efficiently, they'll use them for training. So those are, like, pretty standard operations. For the commercial uses, the first uses are organ tissue, high-value cargo deliveries that typically would go in helicopters or ambulances or ambulances and jets. So our primary customer there is United Therapeutics. It was founded by this wonderful lady by the name of Martine Rothblatt, who runs her business in a sustainable way and said, "Look, we're using helicopters right now. We want to get to a carbon-free version of moving organs around." And so, we're giving her a solution. At the same time, Carol Tomé at UPS wants the same thing for UPS. So, UPS is the single largest order with us in terms of number of aircraft. And so, they have a goal of being net zero, I believe, by 2040. And they're doing it on the ground, they're doing it in the air. They're doing it at their package sorting facilities. And we're their solution to do it in the air.
David Roberts
Let me ask about something like UPS, because I just have no sense of how big a chunk of UPS cargo deliveries is a three-pallet capacity. Do you know what I mean?
Kyle Clark
I do know what you mean. Right now, rough numbers, UPS moves, let's say, ten plus percent. And I don't know these to be true, but they're somewhere in this order, ten plus percent of their cargo in the air. The rest goes on the ground. All that stuff that goes in the air, most of it goes, like, from a regional airport, it goes to a centralized airport, then it goes down to Louisville, Kentucky, and then it gets sorted, and then it gets redistributed throughout the country. And you can imagine that these packages are moving quite a distance, right?
They're moving quite a distance. Let's say I ship something from here, Vermont, to Buffalo, and it goes via Louisville, Kentucky. That's the efficient way to do it when you have these big jets. We have smaller assets, like small electric airplanes. With the data science that we have today, we can say, "Look, this many packages need to go between these two city pairs. Let's just run an electric airplane that has a much shorter distance between these two city pairs."
David Roberts
Skip the sorting in the middle.
Kyle Clark
What they call the radial network, where they consolidate everything out in and go back out. And to answer your question, I don't mean to avoid it, like how big a dent? If you're moving at a lower distance and you're moving it between direct city pairs, then you could take a very big dent. The only packages that it wouldn't make sense to move like that would be the ones that are going transcontinental and they're going from LA to New York, which, by the way, is not a lot of stuff, because companies like Amazon and McMaster-Carr and all the derivatives, they have regional distribution centers.
They're not typically shipping something, unless it's a very specialized item, from Seattle to Miami. They're shipping something from Chattanooga to Nashville, and that's not a huge distance.
David Roberts
So with some tweaks in operations, you could do a big percentage of domestic package delivery with these things?
Kyle Clark
That's exactly the idea.
David Roberts
You talk about battery energy density doubling every so often in new models on the horizon. The main thing I wanted to ask you about is, what are the limits here? Like, is there such a thing as a people mover, as a — you know what I mean? Like with a capacity of 80 people versus three, what are the, in your mind, what percentage of aviation is out of the range of electricity, even in theory? Like, how far do you think it can go?
Kyle Clark
Ultimately, if we're looking out at the horizon 50 years, it'll cover the entire spectrum of aviation without question.
David Roberts
Really? You think even big planes, international?
Kyle Clark
Let me qualify that. So, we think of batteries as lithium-ion manganese cobalt. We have more advanced energy storage mediums that go into electric airplanes. When people ask me, "Are you building a battery electric airplane, or are you building an electric airplane?" The answer is, we're building an electric airplane. In fact, I don't care what stores the energy. It could be a consumable metal air battery. It could be a fuel cell, it could be hydrogen, it could be some type of, you know, supplemental hybrid generator plus a battery. It's still an electric airplane. So, when we look out into the horizon, we keep encroaching on and nipping on the heels of traditional aviation in range, payload, and performance.
And over time, we will consume the regional travel, and then the stuff that goes from New York to Miami, and then the stuff that goes from Miami to Dallas, and then the stuff that goes New York to LA. And there's no question that we are going to consume all of that. It just makes way too much sense not to. It's going to take money, hard work, and technology evolution at every level of the aircraft development.
David Roberts
But if that's true, then all this hype I hear about sustainable aviation fuels, about liquid fuels that everyone keeps saying will be necessary for aviation, you just disagree?
Kyle Clark
Yeah, I mean, it's like a cordless phone. It didn't last very long.
David Roberts
Well, that is a delightfully optimistic note on which to end this. So, you know, I've wanted to say that for years, but I need someone who knows something about things to say it for me. So now I'm just going to be referring to you saying it frequently.
Kyle Clark
Well, all we have to do is say it and we have to make it so. And if it's within the limit of physics, we're going to make it so. As humans, that's what we do.
David Roberts
Awesome. All right, well, thank you so much for coming on and walking through this. Super fascinating, and good luck to BETA.
Kyle Clark
Thanks for the time. I appreciate you covering us. Take care.
David Roberts
Thank you for listening to the Volts podcast. It is ad-free, powered entirely by listeners like you. If you value conversations like this, please consider becoming a paid Volts subscriber at Volts WTF. Yes, that's Volts WTF, so that I can continue doing this work. Thank you so much, and I'll see you next time.
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