Aviation is kind of a touchy subject when it comes to clean technology. It’s generally very energy intensive, and even taking a few commercial flights can massively increase someone’s carbon footprint. One international flight produces more emissions than a family car does in a whole year, and that’s already after you split out the emissions per person. Wealthy business travelers flying private jets produce far more per person because they don’t have other people to split the emissions up with. On the collective level, emissions from air travel account for about 5% of global warming.
The “touchy” part of the environmental impacts of jet flight isn’t in the facts (they’re pretty solid), but in our inability to give it up. Despite how bad it is for the environment, we’re very unlikely to give air travel up. It’s simply too useful and convenient. The last time I flew on a plane was in 2019, and I went from Texas to California in just a few hours, including the drive to the airport and all the usual time-consuming security theater associated with commercial jet travel. The next time I went to California was earlier this year, and we traveled by car. That took up two days (each way) that I could have otherwise spent writing, and that stung the monthly budget a noticeable bit.
If you’re a high-speed low-drag business operator like Elon Musk, every minute spent driving a car or riding on a train or bus probably costs more than my four days of driving across New Mexico, Arizona, and California, so paying the big bucks for Jet-A and getting 2-3 miles per gallon (on top of all the other pilot and jet maintenance costs) still makes financial sense. But, there are always people dunking on them for using private jets.
Otto Aviation Solves This Conundrum (Mostly) Through Insane Efficiency
This environmental issue is what makes Otto Aviation’s recent reveal of the Celera 500L so exciting.
Instead of trying to make the aircraft long and mostly cylindrical like most commercial and business jets, the 500L comes in an unusual teardrop form. With a fairly fat and blunt nose and a pointy tail, the fuselage comes out to a nearly perfect aerodynamic shape. With sharp wings and tail, landing gear that folds away cleanly inside the plane’s shape, and even the engine tucked neatly away, the plane cuts through the sky a lot more easily than other planes.
While not mentioned on Otto’s website, it appears that even the propeller is helping minimize drag. By pulling air from where the teardrop shape comes together in the rear, the propeller may even be sucking on the boundary layer like an experimental NASA design I’ve written about before, helping further reduce drag.
The air intakes for the engine, on the other hand, are spaced out from the skin of the teardrop a bit, likely because boundary layers are very unpredictable sources of air for a combustion engine, whether it’s a turbine or a piston engine.
To take better advantage of this aerodynamically clean design, Otto Aviation chose to use RED Aircraft GmbH’s AO3 engine. Like a jet engine, it runs on Jet-A fuel (basically kerosene), but it’s a turbocharged 12-cylinder piston engine. This helps reduce operation costs, as Jet-A’s economics of scale makes it cheaper to purchase and it’s more widely available. Like a jet, it’s also capable of operating at up to Flight Level 500, or 50,000 feet above sea level. But, despite similar performance, it’s designed to use only 50% of the fuel of a comparable jet engine.
That apparently wasn’t good enough for Otto, though. According to The War Zone, Otto holds multiple patents for systems that make the AO3 even more fuel efficient, including a unique heat exchanger system in the exhaust that increases thrust with less fuel.
The end result of all this is a plane that can get up to 25 MPG, and that’s the whole plane. Dividing it out for the 6 passengers it can carry comes out to 150 MPG per passenger, and that’s roughly three times better than flying commercial. Hourly operating costs are supposed to be only $328, which is a tiny fraction of what it costs to run a business jet (over $2000 hourly).
Range & Safety
The aircraft’s efficiency, combined with the engine’s efficiency, means that the plane is not only fuel efficient, but has a range of up to 4500 nautical miles (that’s over 5000 statute miles, or “normal” miles, or over 8,000 km).
The thought of flying that many miles with nothing but a piston engine keeping you from certain doom might seem a little frightening if you think about it. That’s why most passenger planes have two engines — if one were to fail, it could at least safely limp to safety and not dump you in the middle of nowhere (or worse, in the ocean), right? Fortunately, the RED AO3 engine is actually two engines in one, with two banks of six cylinders that can operate independently. Each bank has its own vital components and accessories, too, so there’s two of everything just like a twin-engined plane.
If the double-redundant engine somehow did fail, the plane’s insanely low drag design would allow it to glide 125 miles if it were flying at 30,000 feet. Otto says this is three times better than other planes. Also, there’s no fuel in the wings like many planes, so that risk is reduced in the event of a crash.
Why This Could Be A Game-Changer For Aviation & the Environment
The big thing here is reduced emissions, per plane or per passenger. If people rode in planes like these, or larger planes that Otto is planning on building (The 1000L is supposed to be 20% bigger), the benefits would be immediate even on existing routes.
On top of that, emissions could go even lower because plane flights could be cheaply tailored to specific passenger needs a lot more closely. For example, in my hometown of Las Cruces, New Mexico, you have to drive an hour to get to the nearest airport offering commercial flights, but there’s a small airport 10-20 minutes away. If flights with these much cheaper to operate planes became common from wherever you want to wherever you want, the rental car industry would certainly suffer, but things would be a lot better for the environment, as fewer air miles would be used.
Beyond the environment, there are many other possible benefits. First off, taking one’s family on a private flight for the cost of commercial would be a lot more convenient and less intrusive. Instead of paying to be treated like livestock or a potential terrorist, you could be treated like a limousine passenger, or at the very least, it could be an Uber-like experience when loading up.
In the air, the experience would be far better than flying coach. There’s more headroom, large first-class seating, and much more room in general.
In both manned and unmanned form, this aircraft could also be great for military applications, and as we know, militaries tend to be among the world’s worst emitters. Beyond the environmental benefits, the range, loiter time, and significantly lower per-hour flight costs make it a great plane for them to use for many applications.
Finally, there’s a lot of room here for electrification or straight up battery-electric drive. The current 500L test plane isn’t electrified in any form, but Otto says that it has made the plane in such a way that it’s very much possible. The greater aerodynamic efficiency alone could greatly help even current battery technology support shorter flights, but as technology continues to improve, it could lead to flights with normal ranges on clean power.
All images provided by Otto Aviation.
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