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Bonkers tri-wing jumbo jet concept reduces fuel consumption by 70% (robbreport.com)
94 points by _Microft on May 17, 2021 | hide | past | favorite | 93 comments



70% fuel consumption reduction would be revolutionary. At 0.9 mach? Even more so.

Highly unlikely to be real.

If this concept had legs I would expect it to have been already gobbled up by one of the major aircraft manufacturers even while the company was in 'stealth mode'.

Not only it's supposed to be 70% more efficient, but it is supposed to be easier to construct. On another article(https://paxex.aero/se-aeronautics-fever-dream/) they are saying they have a "new construction technique" that can build a whole airframe in a week. New, unproven construction technique could be revolutionary in itself - and an uphill certification battle.

Oh and also the engines will be swappable in 30 minutes. And it's so efficient that even though it has two engines, only one will be in use at a time in cruise. So this means they will be close together. This is a safety concern.

Its economy class will be more comfortable than today's economy class too (how can you claim that, that's entirely up to the airlines, unless they won't offer other seating arrangements)

Lots of outlandish claims. Sure, the airline industry has only made very incremental developments over the past few decades and is overly conservative. Probably ripe for disruption. But to claim that you can suddenly leapfrog them on cost, efficiency, construction time and other verticals AT THE SAME TIME... sounds like snake oil to me.


> and an uphill certification battle.

This really makes me wonder how much of the lack of innovation in recent years is regulatory capture.

> If this concept had legs I would expect it to have been already gobbled up by one of the major aircraft manufacturers even while the company was in 'stealth mode'.

The Fermi paradox[0] of innovation. Surly it's possible this is feasible but the incumbent powers are not incentivized to adopt for other reasons.

> But to claim that you can suddenly leapfrog them on cost, efficiency, construction time and other verticals AT THE SAME TIME... sounds like snake oil to me.

Totally. Extraordinary claims need extraordinary evidence.

All that said I really hope we can innovate on this front. 70% fuel savings is an insane amount of pollution we can prevent, among other benefits.

[0] https://en.wikipedia.org/wiki/Fermi_paradox


> This really makes me wonder how much of the lack of innovation in recent years is regulatory capture.

A relatively large amount.

For instance, general aviation use of lead-based fuels. The lead content has been reduced, but building new engines (and certifying them) is not economical. Very few people actually _like_ 100LL fuel.

Regardless, such engines have been built. But then you need to certify aircraft equipped with such engines too.

However, there are plenty of aircraft in the "experimental" category that will gladly take "MoGAS" (aka automotive gasoline). Pilots also like it because it's cheaper and there's no spark plug fouling. Some may be concerned with the environment too.

Avionics on the experimental category are arguably better.

I'm torn on this issue, because regulation saves countless lives and we don't even notice. We do notice when they don't regulate enough (for instance, let companies like Boeing self-regulate) and we get crashes as a result.


Engines close together as a safety concern? I'm not an aerospace engineer but I can't recall that ever being a real concern. It's a safety feature in most cases (less roll in the event of engine failure). The only thing they'd really need is a barrier that is guaranteed to stop a free flying fan blade and a piping design that ensures a fan blade doesn't cut lines to the other engine.


> The only thing they'd really need is a barrier that is guaranteed to stop a free flying fan blade and a piping design that ensures a fan blade doesn't cut lines to the other engine.

That's exactly it.

Not only you have to ensure that any catastrophic failures will be contained, but also that they will not impact either the remaining engine and any fuel, hydraulic or control lines that are feeding that engine. This is easier to prove and certify when the engines are on opposite sides of the fuselage.


When I was nine, I designed a race car that could go 1000 miles an hour, used only one gallon of gas, and could be piloted by anyone who could sit in the seat and tell the computer where they wanted to go.

I don’t see much in the way of material differences here.


Tesla Air


This is the second time I've seen this design posted here, but as far as I can tell, SE Aeronautics is not a real aerospace company, and this jet is pure vaporware. The address on their website is a wedding venue at Mathews Manor. (Probably-not-coincidentally, Tyler Mathews is SE Aeronautics CEO.)

Anyone can throw together a 3D rendering of a jet with extra wings and make all sorts of claims about its performance.


These things often involve a number of newish technologies in the pitch. Using "next gen" engines from existing companies, going composite over more of the aircraft to save weight, using a new shape or in this case more wings.

By the time you stack up the evolutionary stuff - which is going to happen anyway - the revolutionary part isn't that big a deal. And by the time they overcome the challenges of doing a real design, the industry has evolved and the revolutionary concept fades away.


Civil aircraft that actually get built tend to have as few newish technologies as possible, and nothing outlined in this proposal is evolutionary.

More to the point, no evidence is presented of any credentials to do an actual design, and two years ago they were launching a revolutionary seat


>Anyone can throw together a 3D rendering of a jet with extra wings //

Seems not as the first image either has the wings/wing tips on upside down or is missing the upward facing winglets. I've seen aircraft with upward, both down- and up-ward, but never just downward facing winglets.

https://calaero.edu/guide-airplane-winglets/

This sort of engine arrangement seems likely to suffer with centre of gravity problems? The side scoops feed the rear engine so the top engine could be occluded by the fuselage?


This is a render, not a prototype, and the article reads like a press release with the word "bonkers" thrown in a few times.

Until they have a real working prototype this isn't that interesting. It seems like they're trying to drum up interest to get funding.


>the fuel is stored on a bladder on top of the fuselage

I'd feel uncomfortable knowing 200k liters of jet fuel are stored above me, no matter how many layers of (self healing) bladders are protecting it.

Irrational, I know.


All things considered, not _that_ irrational. For example the flight in Okinawa

> The pilots attempted to use the cockpit escape rope to climb to the ground, but the first officer was knocked off the rope when the number 2 engine and right wing fuel tanks exploded, triggering a large fireball that consumed much of the fuselage. The captain subsequently leapt from the window without using the rope.

Now, would I prefer to have the fuel above me or below me? Probably above. But in the wings away from the cabin does seem a bit safer.

[0] https://en.wikipedia.org/wiki/China_Airlines_Flight_120


not irrational at all! After reading about that I went from intrigued to NOPE!


Crazy looking. If they can actually drop fuel consumption by 70%, every passenger and cargo jet in the country will look like that in no time. I'll believe it when I see it, although sketchy drawings (as opposed to a prototype) always make me in favor of a thing.

Seriously, as someone who is not an aerospace designer guy, I would have thought that the turbulence thrown off the front wing would cause problems for the back two (or at least cause them to look radically different).

It's like the flying version of a Tyrrell P34.


> can actually drop fuel consumption by 70%, every passenger and cargo jet in the country will look like that in no time.

That is true if it had an actual reduction in total fuel spend over the journey.

This promises a ~70% reduction in rate, which is not the same thing as 70% reduction over distance, unless someone says at the same speed.

For instance, the double-bubble Aurora D8 did get 70% more efficiency out of the aerodynamics but also by cutting the cruise speed from 0.8 mach to 0.72 to make the aero work.

So more efficient per hour, but longer hours of flight which introduces additional spend.

The SUGAR FREEZE did something similar with extra wings under the main wings like a bi-plane, but again with big savings at mach 0.7 and only 10% at mach 0.8. But of course, the real cost shift there was switching the fuel type to something that can be manufactured out of co2+h20 (like pure methane).


70% less fuel doesn't make sense. The energy required to lift and move a certain amount of weight is a known static quantity. The savings would have to be made up entirely in efficiency, and modern plane designs are very efficient.

Reducing fuel usage to that extent based on wing and airframe shape alone seems rather ridiculous.


Lifting and moving mass can take quite little energy compared to actual air travel energy consumption. Lifting 100 kg straight up by 1000 m at the lower bound of physics takes ~1 MJ. But real life air travel comes to 1+ MJ per just horizontal passenger-km.


They should pull up their landing gear for additional savings


I am not an aerodynamic engineer but I am an ultralight pilot and work for an aeronautic company, and for me, the design doesn't make much sense.

First, having the fuel in the wings is the most obvious choice, it stabilizes the plane and reduces strain on the wing spar. It makes the choice of 3 short wings instead of a single, longer one, and yet, as seen on gliders, longer wings are generally more efficient. It is probably necessary in order to make them thin (which is good) and strong enough to support, among other things, the fuel that isn't in the wings. And having the wings one behind the other doesn't look great for aerodynamics, I can easily imagine the wingtip vortex of the front wing hitting the back wing on the way down.

It looks like the kind of thing that can do well in a simulation with very well defined parameters but I don't expect it to pass the real world test (or even just a wind tunnel).


longer wings are more efficient but generate drag, which makes them an enemy of any high cruise speed.


You are absolutely right.

However the proposed plane has 3 wings, which, naively, would have the same drag as a wing 3 times longer.

Non-naively, it goes beyond my knowledge of aerodynamics, but it is worth noting that multi-wing designs were very popular pre-WW2 but they are almost never seen today, which suggests a design compromise made obsolete by modern technologies.


Multiple wings were popular in the WW1 era and right up to WW2 because the engines were weak, meaning the plane flew slowly and thus needed a large surface area to generate lift.

Lift ~ surface area of wing * velocity^2 https://www.grc.nasa.gov/www/k-12/airplane/lifteq.html

At slow speeds, you need a lot of surface area. As speed increases, the required surface area decreases rapidly.

Remember the first flight was made on what is basically the power of a modern lawnmower and so was quite slow and required massive wings which created all sorts of stiffness problems. The wings could tear off the plane in a sharp turn or even a gust of wind. Imagine a plywood skeleton covered in canvas held together by suspension wires.

https://en.wikipedia.org/wiki/Bl%C3%A9riot_XI

Thus the idea of cutting the wings in half and stacking them atop each other as biplanes or even triplanes in order to make them stiffer while maintaining a high surface area to generate the required lift at the slow speeds of the day. The stiffer wings also allowed for sharper turns, but suffered from more drag. But at those slow speeds, drag was not so much of an issue as it also goes with the square of velocity.

That meant that biplanes had a big advantage in terms of maneuverability and stability and so outperformed the fragile, slow turning monoplanes in WW1 dogfights. But over time, improvements in engine technology allowed for much higher horsepower -- we went from 40hp engines to 1000hp engines in two decades. That increase in power allowed for increased speeds and reduced the need for wing surface area, and with the increased speed, drag became more of a concern, at which point biplanes were at a disadvantage.

But during that transition period in the 20s and 30s, when early monoplanes were introduced and competed with biplanes they would still tend to stall and were not nearly as maneuverable. New materials -- corrugated iron -- were introduced to help stiffen the wings but even then the pilots of the era hated flying these "iron planes" compared to the more nimble wooden biplanes. WW2, of course, changed everything with monster engines and shockingly fast planes, leaving biplanes for the world of hobby flight and acrobatic exhibitions.


> Whether both designs are flying in a decade or simply remain smart but fantastical concepts is anyone’s guess.

So the 70% reduced fuel consumption has not been tested with a built plane on a real flight. Got it.


and the concept hasn't even been wind tunnel tested it seems.


Is this something we're actually going to see in reality?

Call me a cynic, but I've seen innovative new designs for commercial planes since I was a kid, yet here we are nearly 25 years later flying planes that look like they're from the 1950s.


If humanity sticks around, I think we (well, not us, but you know what I mean) will eventually see change toward more advanced, more efficient designs. But when you have an effective duopoly of massive incumbents selling aircraft with decades of R&D behind each individual product (and that's on top of the broader academic foundation of aerodynamics and aeronautical engineering they rely on) to an industry with razor-thin margins and zero appetite for risk, that change is going to be slow.

That said, making a habit of flying people and things across long distances seems kind of wasteful and inefficient, and if we do stick around I'd expect us to be making the kinds of decisions that would lead to us doing less of it. But I think we will have aircraft as long as we have industrialized society.


I suppose we both underestimate how far we've progressed in simulating physics. Either we're utterly, totally wrong in anything related to astrophysics or we have a basic grasp on fundamental stuff like aerodynamics.

If the latter, we don't need to spend billions on R&D for more efficient designs. We just devote the same comparatively few bucks spent on GPT3 and other ML models to inventing a new, more efficient airplane design.

If we did, maybe an improvement like the one in this linked article is bonkers. If so, we could invest in other assets.


I think the issue is less about coming up with shapes that fly well in the sim (or even in the wind tunnel), and more about turning those shapes into practical aircraft. Computers can’t really help us with that (yet) except at a really granular level, with human supervision.

As an example, take the longitudinal fuel bladder in this design. I don’t know how you design a version of that that isn’t subject to very scary longitudinal sloshing and doesn’t have unprecedentedly complex plumbing that will be very, very, very expensive and risky to validate for normal flight operations, let alone emergencies. And that’s, like, the most obvious problem with it, and I’m not even counting all the normal, mundane airplane problems the incumbents have already spent millions of man-hours solving.


This could be caused by physics. Also, it could be caused by thousands and thousands of engineers working on aerodynamics, jet engine efficiency and of course economics all being totally stupid over those 25 years.

By the way, I know someone who just inherited a few million dollars and is looking for someone to create an account for her to transfer the money to.

This is bonkers. Sorry for the really snarky remark.


> flying planes that look like they're from the 1950s

The 1950s?! The DC-8's design has been around for at least 75 million years!


Well, physics also didn't changed much since 1950s...


Engineering has, however.


That's because lots of planes flying today are still from the 1950s.


Not passenger airliners though. The most common passenger aircraft in active service shares the fuselage dimensions with the Boeing 707 which first saw service in the 1950s, but there aren't any 707s left in regular civil service.

Commercial aircraft rarely continue in passenger service beyond 25 years, never mind 65, and the maintenance requirements as well as the fuel bill means it doesn't make financial sense to try.


Is this true? Do you have a source? I have a hard time believing that lots of planes flying today are from the 1950s. That's 60-70 years ago. I did some searching but didn't find anything that would indicate there are any commercial aircraft that old still flying, much less lots - but if you have a source I'm curious about it. Thanks!

Edit: A google image search for '1950s airplanes' shows me very weird-looking planes that don't much resemble what we have today, in my experience. I now disagree with OP too, I don't think there has been nearly as much stagnation in airplane design and flight over the last 70 years as is indicated in these comments.


As the OP said designs, it would be true that many of those designs are still flying today. The 727 and 737 are derivatives of the 707 and the 757 isn't far off. Just different engine/gear/wing/length configurations.

New 737's may have more composites and more modern manufacturing techniques but it's not any radical departure.

For General Aviation, there are tens of thousands of planes from the 50's and 60's still around and the engines they use (Lycoming/Continental) are still based on designs from the 50s with modernized metallurgy, valves and fuel injection.


Yup. Even the fuel injection (in most cases) is based on 1950's designs though.

Incidentally, aero engine makers were playing around with direct injection, electrically controlled turbo waste gates and turbo-compounding at the beginning of WWII.


Commercial aircraft? As in passenger airliners? Not many from 1950. But plenty in use for the past 2 decades. Average age in North America is 14 years

https://www.statista.com/statistics/751440/aviation-industry...

https://thepointsguy.com/news/airlines-oldest-fleets/

There are _plenty_ being used as freighters. Take the DC-3. First flight in 1935. Produced until 1942 (1950 in the URSS). Still in operation.

However, the 737 design is from 1968. Is that better?

In general aviation, there are lots of planes flying from that time. In flight schools you'll see a bunch of Cessna 150s, first flight in 1957. Thousands of aircraft still operational from that era, even some from the WW2 era (Ercoupe)

In the military, we have the B-52. From 1955. It was only produced from 1952 to 1962. Expected retirement is sometime in 2050, maybe later. That's a full century of service.

Planes are expensive. They are expected to be in service for many decades. Maintenance keeps them working almost indefinitely (even more so if they are not pressurized).

Airlines will only retire them when there are other, more economically viable, options(which sometimes includes new models of essentially the same airframe).


It might be true for GA, there's a lot of stuff from the 60s still around, but not for commercial aircraft. The average fleet age in NA is 14 years old. [1]

[1] https://www.statista.com/statistics/751440/aviation-industry...


> A google image search for '1950s airplanes' shows me very weird-looking planes that don't much resemble what we have today

I'd be curious what you found. The Boeing 707 first flew in 1957, and it uses essentially the same configuration as airliners today (with some evolutionary improvements).


This is cool, love to see interesting new designs. Wish the article head touched on feasibility since market economics decide the design of the final product as much as anything, but doesn't make this design any less cool.


I would be concerned about wind shear in takeoffs, but I know very little about planes.


This got some quick downvotes, but it's a reasonable concern. Anytime you reduce the takeoff and landing speed [in pursuit of being able to use shorter runways], you reduce the relative margin against unpredicted wind shear. A 20 knot loss of airspeed [windshear] is more "easily" ignored by an airplane with a rotation speed of 145 knots than one that rotates at 100 knots.


Landing aircraft are spaced ~minutes apart to avoid turbulence caused by the plane in front. Surely wings immediately behind on another suffer significant turbulence and reduced lift?


If this or another design could actually reduce fuel requirements by that much, how much closer would we be to full-size battery-electric planes being viable?

Current requirements are pegged at 400 Wh/kg, while current batteries are between 250-280. A major efficiency improvement should put us much closer.


That's not a bonkers 3 wing airliner concept, this is a bonkers 3 (x3) wing airliner concept:

https://upload.wikimedia.org/wikipedia/commons/f/fb/Caproni_...

https://en.wikipedia.org/wiki/Caproni_Ca.60


x) doubt

at 0.9mach wing will be in the low pressure/high turbolence area of the wing ahead, especially with how low swept these are. at least the third one is off axes, but still.

also, these are the same guy of the huge ass v shaped thing.

how long has to pass before we can call them the theranos of aviation?



We're up to five blades on a razor now. We can at least do three set of wings on planes. Maybe four. Let's think outside of the box.


But why is the gear gown?


If that's an official render then I'm completely dismissing these people.


Yup. "Courtesy SE Aeronautics"

lol


I wish they'd instead phrase it as "Concept Tri-Wing Jumbo Jet Could Reduces Fuel Consumption by 70%"

We don't actually know if the final build would even function. This is just a design discussion.


This is the original official PR Newswire article from March 17th, 2021.

https://www.prnewswire.com/news-releases/se-aeronautics-to-m...


Would this be the first vehicle that stores fuel above the passengers? That seems a bit unsettling.


If fuel is stored along the fuselage, in a bladder, how do you keep it from sloshing between front and back?

EDIT: Maybe toothpaste squeezer design could work.


No idea how they intend to accomplish this on the plane, but in other similar situations the containers have baffles between sections to prevent sloshing:

https://mk0saferacklivebim3l.kinstacdn.com/wp-content/upload...


Similar thing in many liquid fueled rockets - provided you don't want to end up as early Falcon 1 or Juno launches.


Probably the same way that sloshing is prevented when a conventional aircraft banks - using the magic of baffles.


Article specifies a bladder - I don't see how you can have bladder and baffles. Also, baffles would make it difficult to source fuel to engines when ascending or descending.


Does anyone know what simulation software is used to test these models?


3D Studio Max, "OK Google, which font does Boeing use?",. and a pair of 8 sided dice.

There's no evidence of an actual company with actual engineers working on this, and a fair few hints to the contrary if you look at their website.


I don't really care about this particular concept. I am interested in the software industry that provides modelling and simulation software for aerospace engineers, if there is even such a thing. I would love if people could provide some names.


what a load of shit, blatant false marketing--the airflow flowing over that wing is going to disrupt the airflow flowing over the wing behind it.


Looks like a flying centipede!


Things your airline wouldn't want you to know. Also, your EV now charges in 5 seconds.


it's flying kinda low in the picture


I study aerodynamics, so some comments:

- vertically-stacked wings (biplanes, triplanes) are common, but I've never seen 3 non-stacked wings. Not even the Nazis were doing that, which is a red flag for this project actually.

(I think it was France that passed a law that airplanes required at least 2 stacked wings around WW1, as monoplanes had too many structural failures at the time.)

- more wings mean more lift, but also more drag

- one advantage of more wings is that airports support only certain wing spans, so winglets or more wings is a work-around for that. (The result of winglets is mainly to effectively lengthen wing span.)

- very thin wings aid in penetrating the sound barier. This is a subsonic plane in terms of speed, but more accurately it's a transsonic plane (mixed subsonic and supersonic) over certain parts.

- I don't see the second engine, but if it has two, that's adequate for most oceanic operations because other small jets are allowed to do that, and ETOPS. (If ETOPS regulations apply, then engine reliability history is examined.)

- If the engines are too close together, then an uncontained engine explosion can destroy the other. This is fairly common for engines mounted near each other.)


I thought the problem with multiple wings is that the first one pushes air downward (to induce lift), and then the proceeding wings get caught in the downdraft. Just looking up pictures of planes with multiple wings, it seems like it's common to put the first wing at the bottom of the fuselage and then the second wing at the top. The theory being that the second wing will be above the downdraft and able to provide lift.

Anyways it looks like this company is generally considered to be a scam so I don't think this is much more than a 3D render.


Miyazaki came up with this design first...(Howl's Moving Castle)


Caproni did it first. Miyazaki even references it in The Wind Rises.

https://en.wikipedia.org/wiki/Caproni_Ca.60


Looks to me like it has %50 less engines. That will save a lot of fuel but makes it useless for flights over water.


We've been flying twin engine planes over oceans for quite a while now. That's been a think since Boeing and Airbus introduced the 787 and the E350 using something called an ETOPS certification. If anything, we'll probably be seeing a lot more twin engine flights over oceans in the future.

https://www.popularmechanics.com/flight/a11987/for-transocea...


ETOPS was created based on A300 experience in the late 1970s.

https://en.wikipedia.org/wiki/ETOPS#Early_ETOPS


Long before the 787, ETOPS allowed the 767 to cross the Atlantic in the 80s.


I believe ETOPS was developed to help make the 767 a viable twin-engine option for long flights over water (ETOPS-120). That subsequently led to ETOPS-180 etc. Now there's ETOPS-330!

ETOPS-N: N number of minutes over open water, roughly, I think.


The article says "The tri-wing design, with a double tail fin and two engines mounted to the rear".

Two-engine airliners are overwhelmingly the most common configuration today, including for ocean crossings. (I can't tell if you're arguing that 2 is 50% less than 4 and implying that 4 is the standard for water-crossing, or if you think it's a single-engine jet.)


> Its projected range of 10,500 miles, with a top speed of Mach .90 (690.5 mph), is also greater than other jets in its class.

Better range than a 787 or A350.


I think the implication there is sort of operational, that flying in open water, when have an engine failure, flying with two engines likely presents more problems.

Not really my discipline. I don't know how long a twin engine plane is expected to be able to fly on one engine, or under what sort of envelope.


It's also a twin engine aircraft.


I assumed the implication of the OC was that 4 engines was the undisputed standard for long flights over open water, which would be kind of true until like, the early 80s.


The article states “engines” but it is hard to see where the second one might be. There are twin intakes on the body below the tail wings, but I don’t see a second exhaust….


You can see it in the third photo, which is a profile view.

https://robbreport.com/wp-content/uploads/2021/05/Se200.jpg

(Although this view seems to have "only" 2 wings for reasons I don't understand.)


It's a problem of perspective. The third wing starts right above the engine inlet.


Thanks, you're right! I just didn't notice it in all the visual clutter of the double tail fin.


It looks like the second exhaust is along the central axis of the fuselage.


The second engine's exahust is straight out the back of the tail.


I'd wonder how big an engine you can put back there. Designs like the 727 were before turbofans. I'm not aware of any turbofan designs with an engine built into the fuselage. (But that's a pretty fundamental question so I assume it's been looked at.)


The Lockheed L-1011 had an engine at the very rear of the fuselage, though bypass ratios were lower when it was built than today.


That was my point though. It can be done but to achieve fuel savings, which is the objective, you probably need high bypass engines.


The F-22 has fuselage-mounted turbofans (albeit ones with a lower bypass ratio than a typical modern airliner).




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