The World’s Largest Electric Aircraft Just Flew

Heart Aerospace (YC W19) just flew the largest electric airplane ever flown — a 100-foot wingspan, a takeoff weight of 25,000 pounds, and $5 of electricity to get it off the ground. In this episode of Hard Tech, YC's Gustaf Alströmer visits Heart's pilot plant in LA and sits down with co-founder and CEO Anders Forslund to find out how they went from a 3D-printed model to a full-scale electric aircraft in seven years, why the jet engine has left short flights behind, and what cheap electric flight could unlock for the future of regional air travel.

• 0:01Speaker 00

  This is the largest electric airplane ever to fly. It's got 100-foot wingspan, a takeoff weight of 25,000 pounds, and the electricity to get it off the ground costs just $5. Its successor, the ES-30, will fly up to 125 miles on battery alone, up to 500 miles as a hybrid, and recharge in about 30 minutes.

• 0:20Speaker 01

  It's the world's largest electric aircraft by about a factor two. It's the first clean-sheet airliner to be flown in any category, electric or not, in the U.S. in the last 18 years.

• 0:35Speaker 00

  This is Anders Forslund. He's the CEO of Heart Aerospace. Seven years ago, Anders showed me this plane. It was a 3D-printed model that you can hold in your hand.

• 0:46Speaker 01

  It's surreal, yeah. I came to YC with that 3D-printed plane. That was like this size. And now it's, you know, 100-foot wingspan, hurtling down the runway during taxi testing.

• 0:57Speaker 00

  So how do you go from basically a toy model to this? I visited Heart Aerospace's headquarters in L.A. to find out.

• 1:14Speaker 00

  I've worked with Anders since he came to YC seven years ago. Back then, it was Anders and his co-founder Clara and that 3D-printed model. Today, it's a 40-person team in L.A. building a real airliner.

• 1:27Speaker 00

  How would you describe Heart Aerospace in two sentences?

• 1:29Speaker 01

  We build hybrid electric aircraft, but our mission is to reduce the cost of air travel, and we're building the technology to support that.

• 1:35Speaker 00

  With a relatively small team, they're going after something that Boeing and Airbus have not been able to pull off. Heart's plane swapped the jet engine for electric motors.

• 1:45Speaker 01

  You'd be holding a motor that weighed a few grams that you put on a drone and has one moving part. And then you look at the 400-kilowatt ones, it's just like scaled up. So it's this really, really simple thing that has very few moving parts, so it means that you can produce them a lot cheaper. They don't break because they don't really have combustion or fluids, so you get basically zero wear.

• 2:07Speaker 00

  Let's break that down. A jet engine has thousands of parts and burns fuel hot enough to melt metal. An electric motor has essentially only one moving part, no combustion, and doesn't really wear out.

• 2:19Speaker 01

  When you're taxiing with a jet engine, the rest of it is, by definition, is noise. In this, but you have a constant torque profile, so you could spin it at like, you know, 1/10 of the speed is virtually silent if you stand like 100 feet away from it.

• 2:32Speaker 00

  And the power source is eight battery packs laid across the floor of the plane.

• 2:36Speaker 01

  It's eight packs that are like across the floor of the fuselage. It's actually only about four Teslas for this one, carrying that $40 worth of fuel.

• 2:45Speaker 00

  To understand why this is such a big deal, let's look at what's broken about the jet engine, especially when it comes to short flights.

• 2:52Speaker 01

  It's as complex to build a jet engine for a 30-seater as it is for a 70-seater, so it costs the same. It wears the same whether you fly 100 miles or 1,000 miles. So it's pushing the industry into this direction of going larger and larger planes and longer and longer routes. They're extremely inefficient at taxi. You can spend, you know, for a short flight, you can spend 10% of your fuel just taxiing up to the runway. Takeoff is inefficient, landing is inefficient. So that sort of segment of flying regionally is really badly served by the technology that we have today.

• 3:29Speaker 00

  And there's already an existing market. Half of all flights in the world are under two hours.

• 3:34Speaker 01

  There is a replacement market here that's not even driven by cost, the aircraft that we're competing with our 40-year-old designs. Regional connectivity is not about how far you fly, it's about how cheap you fly. This aircraft would be absolutely best if it was flying the shortest possible route.

• 3:48Speaker 00

  Think island hopping in Hawaii or a Norwegian fjord town that goes from being a six-hour drive to 20-minute flight.

• 3:55Speaker 01

  In the last year, you're going from like being 33% better operating economics overall to 48% just because of this increase in price in oil.

• 4:03Speaker 00

  So why hasn't anyone built this before? It started in Sweden.

• 4:06Speaker 01

  And I grew up right next to an Air Force base in Sweden. You saw like the Viggen fighter jets going over the soccer field. And I was always, I think, super excited about that. Really into paper airplanes. Just been fascinated with planes, you know, rockets and all of these things.

• 4:22Speaker 00

  He did a PhD on jet engines and ended up at MIT. That's where the idea found him 12 years ago.

• 4:28Speaker 01

  He comes to MIT, this is 12 years ago, and Johan shows up and he's talking about electric planes. He says at one point that, you know, eventually all modes of transportation will go electric, besides rockets. He's talking about like 400 watt-hours per kilogram, and it kind of felt like a cold arm.

• 4:47Speaker 00

  Yes.

• 4:50Speaker 01

  This time, I was like working on jet engines during the day. I was like tinkering with drones at the kitchen table at night, becoming kind of obsessed with this.

• 5:01Speaker 01

  I was actually doing research on this, being paid by the Swedish government to go around, speak to all the airlines before I even had a company. It's established the relationships with the airlines and the Nordics before I even like tried to build something.

• 5:14Speaker 00

  When Anders got to YC, there was no playbook for this.

• 5:17Speaker 01

  With YC, we were all focused on getting some like early interest from airlines. We got some LOIs from SAS and Bra and Videre, and the three Nordic airlines. We really had no technology. Like, I came to YC Demo Day with a little 3D-printed model. So we went from having the LOIs to them building like the 400-kilowatt motor, which was like the size of a small jet engine. That in turn attracted actual, you know, pre-orders, and then they came from United. And then that attracted more capital, and then we started building, and now we're building towards the plane.

• 5:50Speaker 00

  If you're a founder listening to this, the learning that you should have is every time you need more capital, it needs to be something material.

• 5:57Speaker 01

  Yeah.

• 5:58Speaker 00

  Ideally, something physical you can touch.

• 5:59Speaker 01

  Yeah.

• 6:00Speaker 00

  That you can show that you made. Their first big airline customer actually came out of the spam folder.

• 6:06Speaker 01

  United Airlines came through an inbound email through our info email. Clara was looking at it and she was like, "I think this might be a thing." Like, he was like cleaning out the spam. And that led us like through the front door. We just brought them over, showed them the electric motor we built that was the size of the jet engines we tried to replace, and they kind of immediately got it.

• 6:26Speaker 00

  And the design itself? Most electric aircraft startups try to look futuristic. Heart did the opposite, on purpose.

• 6:33Speaker 01

  It looks very much like the turboprops we're trying to replace. We're not trying to build a sports car. I'd rather build something that looks very conventional but is kind of hiding its Superman cape under the hood.

• 6:44Speaker 01

  This is the first one. We never even tested this one because we just realized that it wouldn't hold. And the new one just goes all the way through to the bottom here, and like it's a big thing, so it's like really sturdy.

• 6:55Speaker 00

  This is the pilot plant. Most of this plane is designed and built right here.

• 7:00Speaker 01

  This is a cylinder body for the actuator, 6061 Aerospace aluminum. There's about 15 machine components in the actuator that we're working on developing in-house processes for.

• 7:13Speaker 00

  In traditional aerospace, this would be a supplier.

• 7:16Speaker 01

  And you'd source it, and you'd get a year to get one. And now you could just play around with it and test it.

• 7:24Speaker 01

  This is the same basic architecture for aileron, rudder, landing gear extension, braking, even in the pitch of the propellers. If you want to build something in-house, you should start with the things that you don't have to go to one supplier, but you go to like eight different, like, so. Then it just scales with the number of technologies rather than the number of suppliers.

• 7:45Speaker 00

  The whole plant is wired like one giant test bench.

• 7:48Speaker 01

  You can deconstruct it like a Picasso painting. And here's the cockpit, here's the cabin, here's the tail. And all of this is being fed, you know, 1.6 megawatts of power. You could keep the aircraft in the air from just everything that's happening here.

• 8:05Speaker 01

  We're going to be testing fault injection, so everything from like putting in programming error to cutting a wire, everything's got to work, even if everything goes wrong.

• 8:17Speaker 01

  Like, the first time you get into Model 3 and you're like, there's just one screen. I think that's a lot of the idea here. As the guy designing this, he worked on the Dragon Space capsule. You can fit up to 36 passengers. But most common probably going to be 30 passengers, which means everybody's going to get like six inches of extra legroom.

• 8:35Speaker 00

  And the heart of the operation is the battery lab, where the team is choosing the cell for the next aircraft.

• 8:42Speaker 02

  This is the battery cell lab, where we are trying to determine what our cell is going to be. We have lots of different cells which are on display here, from Chinese, American, and Korean manufacturers. We can determine which one's going to have, you know, the most flight cycles, the best safety, the cost, and energy density.

• 9:01Speaker 01

  We talked about Elon coming to MIT 12 years ago and talked about like 400 watt hour per kilogram batteries. Do we have any cells that are like 400 watt hour per kilogram?

• 9:10Speaker 02

  The highest thing that we have on this table right now is about 370. One of the manufacturers is producing something at that 400 level that we're expecting to have within the next couple of months. Easily meets our targets for the first generation of the aircraft.

• 9:24Speaker 01

  So you've got the countdown timer there, 23 days. Inspired by YC Demo Day. Yeah. Chrome extension.

• 9:32Speaker 00

  The hardest problem had nothing to do with the motor or the battery.

• 9:36Speaker 01

  It's probably the biggest challenge we've had in the company. One in every thousand flights in the US gets diverted to another airport. You kind of need 45 minutes of loiter and then you need to go to something that could be like 100 miles away.

• 9:49Speaker 00

  Yeah.

• 9:50Speaker 01

  So if you build a battery electric aircraft, you kind of have to carry two thirds of your battery needs to be for reserves.

• 9:56Speaker 00

  And unlike Jeff Fuels, batteries don't get lighter. Their answer is a hybrid engine.

• 10:01Speaker 01

  We're basing it on a very simple turboprop engine, one of the most inexpensive ones. We don't have to use it for most flights, but it's still adding about, I guess, 20% of the upfront cost of the aircraft. And I think it's worth it. You can fly up to 125 miles all electrically and then you fly up to 500 miles with a hybrid system operational range.

• 10:23Speaker 00

  That call comes out of the philosophy that Anders Barra from SpaceX about how you should treat risk.

• 10:29Speaker 01

  Traditional aerospace is like, well, the impact is always catastrophic, so let's minimize the probability. We don't know anything until we know everything. Whereas if you look at, hey, how do we minimize impact to getting it wrong? Then you can select a process that's a lot cheaper, that's a lot easier to iterate on. Planes don't crash these days because of a broken wing, they crash because of broken logic. We want to build a software to find vehicles, the computer on wings.

• 10:55Speaker 00

  Anders has heard all the doubts. For example, why not just build flying taxis first?

• 10:59Speaker 01

  It's super cool, like they're really trying to build a flying car. We're attacking not the helicopter market, but the mainline, you know, like airplane market. While these companies have like three or four passengers, we have, you know, 36. We're also operating from an infrastructure that is already there. You know, there's 5,000 airports in the US.

• 11:21Speaker 00

  Another common question he gets is why not use hydrogen?

• 11:23Speaker 01

  And the same with hydrogen. The great thing about using hybrid electric is that it's already now at a significantly negative green premium. So you're surfing in a much bigger wave. The planes we're trying to replace, they're 40 years old. It becomes an appreciating asset. The plane will actually be better in 10 years than when you buy it. It becomes like buying a house.

• 11:43Speaker 00

  36 seats is only the beginning.

• 11:45Speaker 01

  We love to build bigger planes. The large market is the narrow bodies, the 737, it's the A3320. There's ridiculous backlogs. Somebody doing what SpaceX did with rockets on airplanes just makes sense.

• 11:59Speaker 00

  Longer term, the plane is built for a world with fewer pilots in the cockpit.

• 12:04Speaker 01

  A remote pilot that is supporting many aircraft. Kind of like there's remote operators of the way most. Then we're going to see autonomy happening in cargo where there's, you know, lower stakes. And then, you know, eventually making its way into aircraft.

• 12:23Speaker 01

  Obviously a lot less noise. There's a lot less vibration as well. There's going to be more flights. There are going to be cheaper tickets. So you're going to be able to go to your neighborhood airport and take a plane in the way you actually could in the past.

• 12:35Speaker 00

  It's also why Heart is building it here in LA, the new center of gravity for this kind of company.

• 12:41Speaker 01

  This is the ground zero, the most historic place when it comes to aviation. You have the new space ecosystem that's kind of coming from SpaceX. You know, companies don't build planes, people do. This is the moment of seeing it literally take off. This is obviously a moment I've imagined for the last seven years. And even seeing it going down the runway is kind of gives me the goosebumps. So it's, hopefully I'll get a moment where I kind of start seeing the forest for all the trees kind of thing.

• 13:11Speaker 00

  When this airs, you will have flown the largest electric airplane in the world. Come a long way from Demo Day seven years ago.

• 13:17Speaker 01

  Man, I'm so grateful that you got that opportunity and now the day is here. It's going to be amazing.

• 13:24Speaker 00

  Seven years of hard work finally led to this. Their first flight on Wednesday, August 12th in Plasberg, New York.

• 13:58Speaker 00

  If you start a new hardware startup today, everything that you know about building Heart and your entire career, how would you get started?

• 14:06Speaker 01

  I'm a pretty good duck, right? Like I know a little bit how to swim, I know a little bit how to fly and I know a little bit how to walk. And that's enough for me to know when I find somebody that's great. I would never start a company based on the fact that I wanted to have a company or be a founder. I would start because I really enjoy, you know, a problem. If we can get stuff that is lower emission, lower cost, lower pollution, just better quality of life, we should be doing it.