Engineer the Sky - The Tech Between Us, Ep. 2 - Urban Transport Takes Flight

Matt Campbell
Welcome back to The Tech Between Us! I’m your host, Matt Campbell. We're continuing our conversation with Bob Johnson, Principal at Johnson Consulting and Advisory, as we explore the evolving world of eVTOLs and the innovative pathways it will open for engineers. Let’s dive back in.

For technologies other than electricity, earlier you'd mentioned hydrogen. Are there plans for maybe hybrid eVTOLs or anything like that?

Bob Johnson 
Yes, and that is the big move. Right now in urban air mobility - again, we're looking at short hops, 15 to 40 miles, a lithium-ion battery can handle that. But if you see a lot of the major OEMs, especially in the United States, and by the way we are leading the world in building and manufacturing in OEMs. You'll see that a lot of these OEMs are also working with the federal government, whether it be Department of Defense or possibly now the Department of War, that a battery is not going to last for what they need that to do. So, all the three major OEMs are now doing a hybrid. So that's actually gasoline … gas along with battery. So that will help them stay up. 

If you think about it, when an eVTOL lifts up, 90% of the energy used is to actually go straight up and to hover. Only 10% of that energy is used is, what they say, you get on the wing, you get on the flight and you start going horizontal. 

Now to get back to your question, what are there some other areas? Solar is definitely in the play there. There's no doubt about it. Wind is in play. But I don't hold out for a lot of solar and wind to power these vertiports because we're talking, as I said earlier, one to two megawatts. 

And when you look at a vertiport, I look at it as why are we building these? It's a three-trick pony basically. Yes, it's for transportation, but how can we use that? Let's say a disaster recovery in case of bad weather, hurricane, natural disaster, how can we use this for electrical or emergency medical services, EMS. So we want to make sure that when we build these, who are we going to help? Who are we going to hurt and who's going to be left out? So there are a lot of things that we look at before we put a vertiport in a certain area.

Matt Campbell 
And I'm glad you brought that up because I think it's interesting to take a holistic look at this technology and really think about who does benefit from this. And so long-term, once vertiports are established, will these be just for executives to zip around between meetings and airports or will this be a way to make air travel more accessible and equitable? And I want to know if in your experience, if you'd been exploring those kinds of questions.

Bob Johnson 
Yes, that's probably the number one question that comes up, Matt. In the beginning it will be somewhat pricey, but the whole goal of UAM and AAM is to democratize this type service is to make it equal for everyone. It's just like anything else. I mean the iPhone was totally very expensive when first starting out. If you look at a lot of other things - it's got to get used to, it's got to scale. And the more people that use it, the more that the price comes down. Now regarding infrastructure, we're sort of in a catch 22 right now because we don't really know what the ticket will cost until we know how much the infrastructure is going to cost.

Now by today's standards, for every dollar or an OEM spends to build an eVTOL, it takes $4 of infrastructure. So that's a lot of money that we have to go out and say, you know what? A private company cannot do this together. Government cannot do this together. How do we do what we call a private/public partnership or P3 as a lot of people refer to. One thing that we don't want to do, Matt, is we don't want to get in the same scenario as the business jets. So we are not looking for the affluent. I think once we get into this, and this is going to be a few years down the road, I think it will be determined on how fast and what the demand is to how many we build from each factory. We've got a factory in Atlanta that will be building anywhere from 650 to 1,200 eVTOL per year. The same thing goes up in Columbus, up in Vermont.

We're expecting a lot of things, but we've got to make sure that we educate the public and let them know what we're doing and get their buy off.

Matt Campbell 
And yeah, I think public buy-in is critical for this too, because like you said earlier, there's concerns about noise and safety and things like that. And I've done some interesting reading. Are you able to speak on how the design of the rotors can impact the noise? Helicopters have one big rotor versus an eVTOL may have six to eight or more.

Bob Johnson
From a helicopter perspective, you hear that (imitates helicopter rotor noise), right? Because you've got one blade that's lapping the air and by the time that air comes up, it's slapping the air again. And that's what makes that sound and that's what makes that vibration with an eVTOL. You've got anywhere from 6 to 12 rotors. These rotors are made out of composites. They're very light and the disk loading. They're a little bit smaller disk loading than what a helicopter would be. One of the main reasons that when we do have this sound, all these props are not going to be turning at the same time. Some of them might not even be turning.

We have redundancy built in. There's pros and cons to everything. I don't think you're going to see any of the OEMs that will have a ballistic parachute. Some of the general aviation airplanes have those today, but those add weight and they're not good for the aerodynamics as well. So it's going to be interesting to see how the sound signature comes into play. But I've talked with some people and they've been out at a demo and all of a sudden the eVTOL is flying over them and you'll see people and they'll start whispering. They'll go, shhhh, hey, it’s flying right now, don't talk. And it is up there 1500 feet with a decibel of probably 45 decibels, which is like some of the people say it's like leaves blowing in the air. It's not going to have that vibration where you're knocked out of bed at six o'clock in the morning.

Matt Campbell 
So what other sort of technology will these eVTOLs have on board? Because it sounds like they're pretty advanced machines.

Bob Johnson 
Well, they're going to have a lot of the avionics on board. They're going to have a tremendous amount of sensors on board because even on the ground when we're charging these - copper is going to play a very important role in the components of this - and it's how fast we can charge these eVTOLs. And we've got to make sure that the thermal management does not get up. We don't want fires, we don't want any hotspots going on. So the avionics will play a huge role in this. 
Joby Aviation had just rolled off their first eVTOL, and this was about two months ago. They had mentioned that it took over 18,000 components to build just one eVTOL. So when I look at 18,000 components just for one eVTOL airplane, and I look at an OEM that wants to build 600 to 1200 per year, and then I look at how many OEMs there might be, that's a lot of components and a lot of things that will actually be on. You'll have things such as detected or sense and avoid. You'll have all these meters that make sure we have ample amount of electricity left for if we have to have an emergency landing. And this will also be monitored by these vertiports with let's say what I call a NOCC -N-O-C-C, which is a network operations control center. A lot from the telecom days are coming into play of course with aviation right now. So the person will be able using AI or AI gen type applications to monitor these eVTOLs.

Matt Campbell
And so, you had mentioned that the test flight that happened recently had a pilot on board. Will the first iteration of eVTOLs all have pilots on board?

Bob Johnson 
Yes. The first ones will because we want to make sure that it's safe and we display this to the public. But if you think about AAM and you think about autonomy - autonomous is the end game. That's what we're striving to do. So if we have a four-seater and we've got another seat there for a pilot, if we can take that pilot out and bring revenue in that other seat or two seats, that's what we're striving to do. We want to be safe, as I've said many, many, many times on this. But autonomy is the end game on this.

I mean, you look at a flight today, 80 to 90% of the flight is autonomous. But we want to make sure in the beginnings that we have a human in the loop, on the flight deck of the eVTOL or what we would call fly by wire or on the ground. Just for instance, when you actually get into the eVTOLs, you'll be given headphones, so you'll be able to talk to the ground at all times. So there's a lot of things that really haven't come out that we're doing in this sector that I think are going to be very exquisite, and I think a lot of people are going to look forward to it.

Matt Campbell 
And so where are you going to find the pilots for these eVTOLs that don't exist yet? How are they going to be trained to fly these things when this is such a new technology?

Bob Johnson 
Great question. Just recently, the FAA came out with a new Part 21 to be technical, Part 21-17.B. That is the new powered lift segment for the FAA. Going back again, we've never had this before. We've either had fixed wing or we've had vertical takeoff with helicopters. So how did we blend these two? Right now there's a helicopter shortage, an ATC shortage with the FAA in the United States. I'll just talk about the United States for this sake of this chat right now. So we're looking at a lot of the simulation companies that will basically work with the OEMs to make what we call a digital twin. So you're getting onboard training just like he would be flying a 777 or a 747 or even an F35. We look at this as we want to get the young people excited about this.

We think aviation is a great place to start and this is a lot of fun as well. And I will tell you, I have flown an eVTOL. I flew on in Augusta, Georgia in a simulator about two years ago. And you know what? I got an A from the instructor. I did not do anything bad. You've got basically seven switches that you're working. So if you're pretty agile with your wrist, which most young people are, I think this is a great place for them. One good thing about it, Matt, is that being a pilot in this type scenario, you're going to be able to be at home at night and with your family and children today with a major airlines, you might be on a seven-day furlough. With this, you're going to be able to make your hops and get back - very similar to Uber - you're there at home. So, there's a lot more to come with simulation.

Matt Campbell 
Yeah, sounds like a pretty compelling career to me. And then earlier you'd mentioned that there was a shortage of air traffic controllers, and that's something I want to get into a little more because anyone who's flown a hobbyist drone knows you really can't just fly even a palm sized drone anywhere you want. There's a lot of rules and regulations. So how will UAM fit into the existing paradigm of air regulations?

Bob Johnson 
Yeah, I think the toughest part is managing the airspace. When you think about airspace compared to what we drive on our roads and highways, there's a lot of room out there in the air. I mean on the roads not so, be it a telephone pole or a stop sign that could be a hit. So we want to make sure that we get along with everyone in there. We want to make sure that as we say, stay in your lane. So with what the eVTOLs are going to be flying, what we say AGL or above ground level. What's the altitude that they will be flying? Anywhere probably from 1500 to 3000 feet. A commercial airliner once it gets up to altitude is anywhere from 25 to 35,000 feet depending on the mission of that flight.

So we want to make sure that we have a lot of the digital transformation in place. And that's the beauty of what we're doing in AAM, that it's all digital. If you look at our ATC program right now, it's not digital. And that's what we're trying to fix. And I'm not sure where we're going from a governance standpoint on the ATC, are we going to privatize the ATC? Are we going to keep it in the government? That remains to be seen, but I will tell you that being digital is a lot safer than the other side. So we want to make sure that we've got our corridors. And I think starting off, we might be flying over certain highways that we know where they are. I mean even the UAS, or for lack of a better term, drones today, the under 55 pounds as UAS have corridors that they can fly in and the FAA has just passed a new law flying beyond visual line of sight. So I think that is the key question. I will say that I think the holy grail for anything from drones up to advanced air mobility is that when the crewed can talk to the uncrewed and we can fly beyond visual line of sight, that's what I would call the holy grail.

Matt Campbell 
And that would open up potential fly by wire type of situations where you have a pilot on the ground somewhere. And so there's a lot of moving parts that we've talked about. And obviously this isn't going to launch tomorrow or next week, but when might we start looking to the skies for urban air mobility because there are some test fights and we do have cargo delivery drones for fast food orders today. So when are we going to take the leap to having commercially available passenger flights?

Bob Johnson 
Yeah, the FAA has just passed some new rules this past summer. The MOSAIC rule for light aircraft, you mentioned the drones. But if you look around now, we're actually already doing this. A lot of people don't really understand that. And yes, they are demo flights. There's no passenger flights right now, but if you look at it, the Olympics are coming up in 2028 in LA. So there's a big push from our sector to innovate in ‘28. Now, if you look at some of the OEMs right now, they've already - like Joby and Archer - they have already planned their networks in the LA area. You look at places like SoFi Stadium, you look at the campus of USC, you look at some of the other airports in Southern California like John Wayne Airport, as I mentioned earlier, a lot of these fixed space operators are playing a key role in this.

And again, you got to remember, we want to make sure we go where people can fly these eVTOLs. We want to make sure that they can afford these eVTOLs. We don't want to go anywhere where nobody can pay for this. So there's a lot of moving parts in this. But you will see as of today out in Japan, Osaka World Games, a lot of our three and four main OEMs are flying there - doing transformational flights and demo flights. And of course, I think the first place that you're going to see this is happening right now over in the UAE, Abu Dhabi, and other places like that in the Middle East that they've got the area that they want to do it. And they're building vertiports over there right now. So I'm very excited to see those vertiports will probably be finished by the end of this year, middle of next year. So it's going to be exciting to see how they build these vertiports because as we always say in aviation, if you've been to one airport, you've been to one airport because each vertiport is going to be a snowflake. Each one is different. So it depends on where it is, what the temperature is, what the weather is like, where's electricity, how do we juice this thing up? A lot of factors will go into that.

Matt Campbell
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