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Comment by karmajunkie | Hacker News Reader

I feel like I see these kinds of proposed improvements to air travel (e.g. this, improved seat designs, improved volumes, etc), and yet, we're still flying in the same basic design with ever-smaller seat allocations as we have for decades. What are the chances planes like this will actually see the light of day in our lifetimes? It feels like i'm more likely to see fusion become a realistic contributor to the power grid than I am to see air travel change in any noticeable way (for the common flier at least, discounting fares like transoceanic business class).

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Airplanes have changed, but in ways not immediately visible.

The Dreamliner is something like 80% composites by volume now, a material profile almost unthinkable 30 years ago.

But the visual dynamics of the design changes have been far less dramatic.

I do think we may see things change significantly with eVTOLs and battery tech improvements.

Major increases in energy density plus solid state (for safety) would probably trigger a Tesla-fication, and at that point the incumbents will inevitably be late adopters and some upstart is going to build something new looking.

Finally, if shape-memory polymers ever really take off, we could see some exciting things. Imagine a dynamically shaping airfoil, or, way out there, a wing which can translate itself from wide body to delta with almost no moving parts required to do so.

> Dreamliner is something like 80% composites by volume now, a material profile almost unthinkable 30 years ago

This—and no bleed air, fly by wire, et cetera—are big. But not on the level of air frame improvements. We’ve been stuck in a local optimum due to overconsolidation for decades now. We’re seeing it bleed into safety simply because complacence evolved into corruption.

Excellently said.

I would love to see a regulatory world where experimentation outside of the high-end is more prolific. Even the constraints that were put on UAVs by the FAA have stifled that spirit in a real way.

Where is the hacker culture in aviation that we've been amazed by in the AI space? Even people doing cool things as small groups, like the black arrow guys, are just building in the same local minima.

> Where is the hacker culture in aviation that we've been amazed by in the AI space?

I mean, if you mess up your AI model, it generates photos of black Nazis or people with an extra arm. Everyone laughs at you a bit.

If you mess up your plane, it kills people. There are absolutely people building experimental aircraft, but for good reasons there's a bit more caution involved.

Planes that kill freely consenting adults would be fine. But the tricky part is that this would also exclude employees of aircraft companies since they can't be directed to fly on such a plane. If the CEO of Boeing were willing to pilot an uncertified deathtrap of their own making over the ocean that should be allowed.

But it’s ok though, because the rest of us will just pick up the bill and clean everything up when Timmy-the-cowboys-unhinged-plane falls out of the sky over a populated area, or the ocean or something. No big deal right? Fuel and emissions don’t have an environmental impact, so people can just fly whatever they please around and the rest of us should just put up with it, because god forbid we put a stumbling block for those mighty captains of industry.

"sky over a populated area" seems like you're putting words in my mouth. I explictly said that having them fly over the ocean to avoid exactly this kind of externalty.

As for the environment, well, this is a self-limiting problem. Either it was only a small aircraft or they're rich and now dead and their money can be used for cleanup.

> Where is the hacker culture in aviation that we've been amazed by in the AI space? Even people doing cool things as small groups, like the black arrow guys, are just building in the same local minima.

Well, a basic body + wings shape, anyone with moderate skill can construct that with a kit in their garden shed and fly it.

But all these exotic design ideas? These require immense amounts of compute power to design them so that they'll actually take off and substantial investment into manufacturing tooling to manufacture them, far surpassing the capabilities of all but a very few very rich hobbyists, and people with that kind of money generally don't subject themselves to the high operational risk of general aviation. Even in cars there's no one working on home-builds for carbon composite stuff, and the potential for failures and the risk of said failures to not just the pilot but everyone on the ground there is orders of magnitude lower than with planes.

And on top of that come the regulatory issues associated with anything that flies. There are many MANY MANY orders of magnitude less people with pilot licenses in the first place, most of Europe doesn't allow flights from anything else than a licensed airstrip (although the US is different there IIRC), and new designs require an immense amount of certification paperwork, which is also the reason why it took until last year to get unleaded fuel certified (whose rollout will take at least 3-5 years).

Pressurisation is better. In the 90s I would always have ear pains, which happened to me only once in the last 15 years, on an old brazilian b777.

Not sure if this is true, you can see that on any device with pressure meter (basically all 'smart' watches and phones), the standards are 2000-2500m altitude. Once you can create an altitude X inside the plane, you can do say 70% of X too.

Maybe just your condition improved?

New composite ones like A350 and Dreamliner have cabin altitude of ~1800m

Higher humidity too.

I don't know. My bottles of water aren't completely flatten when we land, something that I remember was always the case. Keeping in mind flying in the 90s means taking planes manufactured in the 70s and 80s (including a Caravelle!).

And yet Boeing has yet to backport all that fancy carbon fiber and stuff to their bread and butter 737…

Just because a 737 is used for shorter flights doesn’t mean people wouldn’t want higher air pressure, higher humidity, larger windows, quieter cabins, etc…

So disappointing they keep cranking out the current 737 lineage.

Modern airliners are drastically more fuel-efficient than planes like the 707. Fuel efficiency is often what drives a new design. The 757 I worked on came about because of a 35% more efficient engine design. The MAX came about because (drum roll) 15% more fuel efficient engines. These make for enormous operational cost savings.

> we're still flying in the same basic design with ever-smaller seat allocations as we have for decades

We have a rent-seeking duopoly of airframe designers. The history of commercial air frames ended in the era of the Concorde.

What we need is competition, and national leadership willing to bet on it.

No, aircraft frames are the way they are because they balance the billion different requirements the best. A blended wing body is nothing new.

> aircraft frames are the way they are because they balance the billion different requirements the best. A blended wing body is nothing new

One big one being the fixed cost of new air frame development and certification. Nobody would incur that expense unless forced to by the competition.

And yet new airframes do get certified.

> yet new airframes do get certified

Last one was the 737 Max in 2017. It’s a derivative. The last truly new frames were the 787 in 2011 and A380 in 2006. Both focussed on subsystems, propulsion and materials for their novelty; only one has been a commercial success.

One successful (two attempted) new airframes in over two decades is extraordinarily slower than the pre-consolidation frequency. It is also notable that neither attempted to introduce a new air frame that directly competes with the other’s; Airbus and Boeing trade market segments. There is zero head-to-head competition.

Modern planes are a marvel of engineering. And newer planes are more comfortable. That doesn’t change that we’re stuck in a local optimum due to a cessation of risk taking.

Why do you keep thinking competition is what prevented blended wing bodies? Blended wing bodies make big trade offs that don't neatly fit with commercial flight.

The analysis of different lifting bodies is fairly fundamental aeronautical engineering work every student learns. There is no weird conspiracy here.

> Why do you keep thinking competition is what prevented blended wing bodies?

Never said as much. OP asked why all planes since the 70s look about the same. It’s because there isn’t a sustained budget for experimentation.

> no weird conspiracy

Never said as much. It’s not exactly groundbreaking for entrenched supplies to cease innovating and focus on extraction.

> Never said as much. OP asked why all planes since the 70s look about the same. It’s because there isn’t a sustained budget for experimentation.

Bullshit. There is tons of money for innovation, every single manufacturer is trying to squeeze 1-2% efficient improvements across the board. To say there is no funding for innovation is hilariously ignorant.

> Never said as much. It’s not exactly groundbreaking for entrenched supplies to cease innovating and focus on extraction.

Cool, can you show me what numbers you're looking at that even hint that these blended wing bodies are better than contemporary commercial designs?

> Bullshit. There is tons of money for innovation

I heard almost the same out of a Lockheed executive about launch about a decade and a half ago. A dollar of R&D can travel differently at a cushy corporation than at one in competition.

> can you show me what numbers you're looking at that even hint that these blended wing bodies are better

No, I have never defended this design—I have no specs. A better question is why you’re so convinced this optimum is the global one.

> Cool, can you show me what numbers you’re looking at that even hint that these blended wing bodies are better than contemporary commercial designs?

Department of the Air Force Climate Action Plan, October 2022 [0] (p17) “For example, development of blended wing body aircraft could drive transformative changes, as this aircraft design increases aerodynamic efficiency by at least 30 percent over current Air Force tanker and mobility aircraft” [Note that Air Force tanker and mobility aircraft are similar to, and in some cases simply militarized versions of, commercial airliner or air transport designs.]

The same report (p19) identifies development and testing of a full-scale blended wing prototype by FY27 as a Key Result of the Action Plan.

[0] https://www.safie.hq.af.mil/Portals/78/documents/Climate/DAF... [PDF]

> OP asked why all planes since the 70s look about the same.

All commercial passenger airliners (and there are some exceptions there, but in different directions than blended-wing-body) look about the same, but not all airplanes do.

> It’s because there isn’t a sustained budget for experimentation.

No, its because there are various technical challenges with blended wing-body aircraft that have to be balanced against the reduced drag and resulting better fuel efficiency, such as structural challenges if you want continuous internal cabin space; access if you want to be able to evacuate them as efficiently as a tubular fuselage aircraft, etc. Some of those have had progress over the years (e.g., the structural ones) as material science has advanced.

There are blended-wing-body designs (or the related but more extreme flying wing design) that have been produced, mostly as experimental or military aircraft (several US strategic bombers have been blended-wing-body or flying wing designs: the B-1 is a blended-wing-body (also with variable sweep wings), B-2 and B-21 are flying wing designs.)

There's been more competition in the regional market including clean sheet designs by new entrants, but they're all conventional tubes and wings and podded turbofans too. China's state funded A320/737 competitor is a clone with a shared engine platform too.

Improving on current generation airliners is hard compared with improving what flew between 1920 and 1950, and consolidation happened because it wasn't profitable. Airlines and financiers don't like uncertainty either.

The A350, a clean sheet composite design, was certified in 2014.

You’re right. The A220 and A350 were clean sheets introduced in the 2010s.

A220 in 2015 I think was also clean sheet.

Both of you are correct - there is a duopoly because of the complexity, and the duopoly has no real incentive to change, given that the current local optimum seems to be working for the foreseeable future. There is no pressure to innovate, and a strong one to keep the status quo.

And yet efficiency gains are vigorously pursued and adopted, where real - and most recently, that has been with engines and composites. Meanwhile, the blended-wing concept has been experimented with for over a century, and it has never demonstrated a compelling improvement. Until I see a proposal that comes with a paper explaining what recent innovation has made things different this time, I will remain skeptical.

I am sceptical, too. There are no efficiency numbers on their website, just marketing boilerplate.

In terms of pure frontal area, their design looks fatter.

Would be interesting to see some drag data from wind tunnel tests.

The airframe designers don't decide the seat space per passenger.

They can include all of the spacious reclining seats and lounge sofas as they want in the design, and airlines will spec it with seats and seat pitches that produce the greatest profit per flight by maximizing the number of passengers within the limits of safety regulations.

> airframe designers don't decide the seat space per passenger

Sure? Seats aren't part of an airframe.

National? Which nation?

This is a multifaceted issue, involving the duopoly of commercial airline manufacturers, strict regulation, and massive subsidies.

It costs Boeing 10s of billions of dollars and usually around a decade to design an aircraft from a clean sheet, with very little incentive for truly disruptive innovation. Developing and testing a wholly new design like this would probably take double the time and more than double the cost. When your assembly, all testing, designs, control systems, and pilots have been optimized "wings on a tube" shape for 70+ years, I'd imagine it's difficult to pivot the core design that drastically.

I'm hoping to see some of the government subsidies shifted towards more competition with Boeing's recent failures, but lobbying is powerful, so we'll see.

I don’t think you’re likely to see a significant change to the flying experience (at least not for the better) as long as most customers continue to prefer the cheapest, most terrible option.

Maybe somebody succeeds with a delta-wing design, but the highest-profit configuration will still be to make the seats as cheap and terrible as possible.

There is a demand for more luxurious aircraft travel, but at the moment it's too costly to provide.

If BWBs become a thing, maybe the value of cabin space will decrease to the point where paying for a business class - or even premium economy - seat for long-haul travel is attractive for more people.

I did some Googling and apparently the base price ratio for business class to economy class is about 3.6 to 1. Some of that is all the other frippery - lounge access, priority baggage, better food, more personal service etc. etc. So at a rough guess providing just the bigger seat would attract a premium of maybe 3x economy class.

At the moment, New York-London with United is about $600 and business maybe $1800-$2000 (so perhaps a little bit under the expected premium, but in the ballpark). For most people, an extra $1400 is a big ask.

But imagine a world where the economy flight is $200 and business class $700. I suspect a lot more people would choose business class in those circumstances.

Some of the people who currently fly economy would start flying business, but a huge number of people who are currently taking Greyhound buses, driving, or choosing not to travel at all, would start flying economy.

I agree. I am disappointed that NASA abdigated its role in driving forward not only space but aviation to commercial interests. It made, and still makes, many people very rich, but profit motives lead to the masses to feeling, and being handled, like cattle.

I'm particularly frustrated by the dearth of general aviation as a means of travel outside of the wealthy. We built small airports EVERYWHERE, and in most cases they sit rotting in rural areas instead of being hubs of inter-city trade.

I have plans to change that, but the aviation space is notoriously coin-operated and high impedance. Even with funding it's going to require some serious SV-style hacking to change anything meaningfully.

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