I had a great conversation recently with Miquel Ros on his Allplane podcast. It was a couple of hours of good discussion across a range of aviation-related topics, and I encourage people to listen in here instead of just reading my gloss.
My projection of aviation refueling through 2100 with its broad error bars was central. We had a good discussion about the drivers of the projection.
First, there will be a slower recovery of aviation post-COVID-19, in my opinion. Part of this is structural, as the 20% of passenger travel that is business travel will not return to the same volumes because clients will refuse to pay for road warriors to show up weekly when they are still not requiring staff to be in offices, and a couple of years of remote teams will have given most of them the evidence that remote consulting teams work at least as well as in-the-office teams, for what that’s worth. I say this as a former consulting road warrior, by the way.
Another part is that just as 9/11 introduced a lot of annoying security theater which was a barrier to pleasurable travel, especially in the US, COVID-19 has introduced a different set of secure travel theater which compounds this. Not that it’s unnecessary, but there are going to be more hoops and inconveniences, and some people will just say “Yeah, no.”
Other people have gotten out of the habit of flying for vacations. And for many, it was just a habit that’s now broken. They’ve figured out different ways to enjoy their downtime, and realized that travel was, for them, a hassle that isn’t worth returning to.
And, of course, everything in the passenger aviation industry is struggling to return to lower levels of service. I’ve flown recently and the staffing, equipment, and delay challenges are obvious even with a casual eye. Looking at the attempts to return aircraft to service from two years of being parked, and the challenges with getting higher-status flight crews, never mind ground crews and security personnel sufficient for shifts, makes it clear that the industry is struggling with basic logistical issues which will take a while to overcome.
In the longer range, global population reaching its peak somewhere from 2070 to 2100 from 9.7 to 11 billion people had an impact on the demand toward the end of the century. Closer in, refueling with SAF biofuels and electrification will be more expensive initially. Meanwhile, increased affluence of the global population will drive demand up, but things like China’s 40,000 km of high-speed, electrified grid-tied rail and autonomous electric cars running overnight between cities will constrain growth. Lots of factors.
And as I freely admitted, battery-electric intercontinental commercial passenger air travel requires some breakthroughs. It’s not just battery energy density by mass, but power management, airframe, and propulsion innovation, all of which I’m tracking.
We also spent time regional air mobility, with my maturity model through 2040 with electric aircraft, autonomous flight and digital air traffic control curves. There’s a disruption of commercial aviation beginning, and it’s going to start with smaller electric planes flying between smaller airports. Given that there are thousands of underused airports on most continents, the infrastructure is going begging.
Electric aircraft are the easiest part of the small commercial segment, with current battery energy density being fit for 4-19 passengers and 200-400 km flights. The problem there is the business models for that scale of aviation, and there are many people exploring them, including a firm I’m advisor to, ELECTRON Aviation, and a firm I’m an advisor to that is still in stealth mode.
Harder, although not much, is autonomous flight. It’s a lot easier to taxi slowly without a lot of other moving vehicles, then takeoff from a runway with nothing on it, then fly with nothing around for long distances, then land on an empty runway and taxi again with few other vehicles, than have a car autonomously dealing with 120 kph traffic, pedestrians, bicyclists, traffic lights, and the occasional leaping ungulate. I had that conversation with Kevin Antcliff, a second-generation NASA guy who is now product lead over at XWing, which is already flying autonomous cargo runs in test mode. The problem there is getting approval to fly people over populated areas without a pilot, something that will take a while and involve a lot of proofs of safety engineering.
Finally, there’s digital air traffic control. Once again, not actually that hard technically. Keeping track of a few hundred small objects in a big 3D space and making sure that they don’t hit one another or run out of fuel and fall out of the sky isn’t actually difficult with today’s computers. What is difficult is getting transponders on everything in the sky, getting everything in the sky speaking the same computer-to-computer language displacing English as the language of air traffic control globally, and getting everyone signed off that it’s safer than current air-traffic control. That’s the longest leg of the maturity model, not likely to be in place in major markets until 2040 or so.
A lot of the topics were gray rhinos, which is to say the useful risk management metaphor from Wucker, as opposed to the get-out-of-jail-free card that is the black swan material. Climate change is perhaps the ultimate gray rhino, of course. What is a gray rhino?
“The Gray Rhino is a metaphor for the threats that we can see and acknowledge yet do nothing about: the two ton thing that should be hard to ignore, but from which we look away even though it’s in our interest to get away before it charges. It may be pawing the ground, snorting, and getting ready to charge at you; or it may still be a ways up the road when you still have time to manage things before they become urgent.”
Pro-tip: ignore the black swan material, get Wucker’s book and internalize the messages.
Aviation has been staring down the throat of the gray rhino climate change for 40 years, and has done very, very little of any substance. Aviation emissions have soared with flights while SAF biofuels have barely been used in blended or direct flights on the tiniest percentages of routes. COVID disrupted that, but aviation is attempting to soar again, once again with precious little real climate action.
But they face headwinds. The climate change gray rhino comes with the carbon-pricing — or even just equivalent to electricity taxing — gray rhino of aviation fuels, something finally starting to occur in some jurisdictions if not others. As I published a while ago, Europe is finally including aviation fuels in their carbon-pricing approach, as is Canada, and the US is, par for the course, instead subsidizing lower-carbon alternative fuels. Why does the US hate pricing negative externalities, one wonders?
I was typically acerbic on the podcast about urban air mobility and evtols, the Jetsons’ fantasy that has sucked so much useful money and talent out of the ecosystem with zero value likely to come out of it. No market to speak of, underfunded billion dollar decade-long certification paths and overly complex aircraft that they want to fly over children’s playgrounds. Having spent a lot of time working with technical and business intellectual capital, I feel comfortable in saying that there is none in this space worth investing in.
There will be electric rotorcraft in our skies in 15-20 years, but they will be doing the same jobs helicopters do today, in the same volumes, which is to say a declining market as UAVs suck market share out of the bottom end of the market for inspections, camera work, emergency response, and organ deliveries. And they won’t be tilt-rotor safety risks, but fixed rotor, likely much more like scaled up quadcopters of today than not. Simplicity is the superpower of electrification, and the current crop of tilt-rotor evtols are about as simple as the Black-Scholes-Merton model for financial options.
A bunch more was on the dead end of hydrogen for aviation, and the corollary dead end of SAF synthetic fuels. Green hydrogen is never going to be cheap even when it’s clean, as I pointed out in my report on northern African green hydrogen manufacturing for the illusion of a European energy market. It’s always going to be more expensive than SAF biofuels because with biofuels we have nature doing half of the work, while with hydrogen and synthetic fuels we are doing all of the work.
Hydrogen itself is deeply ineffective as an aviation fuel replacement. It has great energy density by mass, but terrible energy density by volume. That’s such a problem that there is no path for the high energy requirements of aviation in gaseous form, so it would have to be liquified, leading to a large number of additional problems. Not least of these is that it must be in globular tanks chilled to 24° Kelvin, around 290° colder than humans like, and inside the fuselage with passengers. And it loves to leak given the tiny size of the molecule, and loves to ignite in a wide range of concentrations in the air. Explosive hydrogen in a pressurized tube in the sky full of souls isn’t going to happen because aviation values human life.
Synthetic fuels are more effective but much more expensive, and will always be more expensive than biofuels. Given the inevitable disruption of fueling with battery electric from below and stalk cellulosic biofuels, there is more than enough less expensive fuel than hydrogen or synthetics to replace fossil fuels. But it won’t be cheaper, so that will be weighing upon aviation demand.
We spent a bit of time on the waste of money and talent in aviation when there is such a pressing need for real transformation. Aviation, like many other domains, is riddled with worthless nonsense that is overhyped and won’t deliver climate value when we are facing a climate crisis and real solutions are often begging for capital and talent. Urban air mobility evtols and hydrogen are just two of the examples. Ground effect ekranoplanes are rearing their pterodactyl heads again. Ultra-short takeoff and landing electric planes are pretending they have non-military use cases. Hypersonic is booming (and busting) again.
Brilliant aerospace, mechanical, and electrical engineers are wasting time, intellect, and money in dead ends in aviation. A well paying job struggling with intractable realities surrounded by delusions of the Jetsons isn’t moving the needle on anything remotely important. Stock options in UAM and hydrogen aviation firms are worthless. There are aerospace engineering jobs going begging in the eCTOL and SAF biofuels space which will actually move the climate needle. Many of the evtol crowd have long track records of hype fails, having come from the equally clearly non-viable airborne wind energy space.
Engineers working on hydrogen, evtols, UAM, vertiports, hypersonic passenger planes, and synthetic fuels, I’m sorry your babies are ugly. I know it’s fun to work over well-hyped, well-paid, technically challenging nonsense, but there’s a lot of good and necessary work to be done in actually useful technologies. Pivot. Please. Real aviation solutions need you.
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