For decades, new airliners have mostly been the tube-fuselage-and-two-engines design, with the exception of the four-engined A380.
I am guessing that this is because the modern A350, Boeing 777, Boeing 787 twin-engine design is about as fuel-efficient a design as engineers can possibly draw up, is that correct? The only improvements we’ll probably see in the future would be things like materials, small tweaks like wingtips, bigger windows, but by and large will we never see a new airliner design that is NOT of the twin-engine type?
In other words, no bizarre things like flying wings, triangle-shaped airliners, biplane-wing-design airliners, etc.
Boeing looked into blended wing body designs, but the design tested very unfavorably with passengers in mock-ups.
Future generations may not be so uncomfortable with flying in such a configuration though, so who knows what may come in a few more decades.
Anytime someone has said some design is “un-improvable” (though perhaps in other words) they’ve been wrong. (See such pronouncements from the 1800s…) Perhaps this time will be different, though?
In the overall scheme of things, the “decades” since this design came to be are but a blink. The future is inconceivably long.
We are likely in the trough in between innovative eras. While I might be missing something, trains went pretty much unchanged for almost 100 years until diesels (and then high-speed ones) came along. That’s usually how it goes, right? Punctuated equilibrium.
Here is a possible taste of the future. In other words, I doubt the airliners a 100 years from now will look or function anything like those of today.
Define “improve”…
It isn’t necessarily to do with a single objective measure of technical efficiency, but also balancing the technical requirements with what the potential travellers will want and need.
That’s true… although there were definitely incremental improvements over that time period (a UP Challenger is quite a different beast than the classic “Old West” steam locomotive).
Basically there’s the invention of something, then a period of “adaptive radiation” (to borrow a biological term) where there are all sorts of varieties of the item developed, and over time, the item evolves down to a mostly optimal common form or a few common forms, if not necessarily common designs. Cars did this, airliners have done this, and even things like mobile phones have done this- settling on a single-button, touch-screen design.
Airliners are pretty much waiting on some new major change before their design’s going to significantly change. That change may be something as pedestrian as much higher fuel prices, or be something really revolutionary that we haven’t even thought of yet.
They might go electric: Solar Impulse - 8th Leg from Nagoya to Hawaii
Ok, it is slow - very slow. It is taking 120 hours to fly from from Japan to Hawaii and they had to wait two weeks for the weather but, hey, Orville and Wilbur had a couple of problems too.
I think we can see some further fuel efficiencies, at the very least by getting rid of the windows. A row of plasma screens running down the length of the passenger compartment, taking a continous camera feed, should simulate the needs of someone who grabs a current window seat, and possibly be able to switch from the port feed to the starboard feed or bow and stern, as desired
Conventional wisdom = conventional design, But I do think that things should be getting bigger and not smaller. What I think we are at the limit, is the biology barrier. The amount of time we are willing to stay in a confined space for up to 36 hours, not counting transit time waiting in the airport and collecting baggage.
Since star wars style anti gravity is not currently being researched, one would think that the next possible choice would be a hybrid zepplin / airliner. The only problem, is what size is large enough, to offset embarkation and debarkation at ports and not airports and the amount of grief they get from the FAA, as they are not conventional airplanes.
Declan
There might be some features of an aeroplane that are un-improvable; for example the shape of the nose for maximum aerodynamic efficiency. (I’m talking subsonic here) As far as I am aware that hasn’t changed in decades.
My aero egineer son will talk your ears off about how disappointed he was with both Boeing’s and Airbus’ latest offerings, that they did not change/improve the basic design. I’ll ask him again - I think the thing he thinks should be done differently is changing the tail/wing configuration - such as placing the “tail” at the front. I think he also favors the “flying wing” approach.
His opinion is that the companies did not want to risk an unconventional design, which customers would question, causing arilines to resist. Also, if you propose a “traditional” redesign and have problems, they can be overcome. But if the redesign is radical and there is the least hiccup, that could pose greater difficulties.
With only 2 players combined with the huge costs of developing a new plane, it is difficult for one to risk change if the other won’t. Another issue is existing infrastructure - there are challenges to introducing a vehicle that will not fit with the majority of existing airports.
My son does rockets rather than planes, and I know next to nothing about either, but his strong opinion is that there is no question that proven basic improvements could currently be implemented.
I guess that means the answer is something that will require a rocket scientist?
This is huge factor. Incremental design improvements are cost effective, radical design changes aren’t. We’re just now replacing incandescent light bulbs with better designs. Incandescent bulbs have always been horribly inefficient, but look how difficult it’s been to change to some other form of lighting. “Don’t reinvent the wheel” is such an engineering mantra that we’d be still using square wheels if that’s how they were originally designed.
Also, I’m pretty confident that when we last discussed this my son said there was a ton of readily available info on-line discussing this issue. I guess he participates in pretty specialized discussion forums, blogs, journals, newsfeeds, etc. My impression was that for someone in this profession, this isn’t even an obscure issue. I never personally searched for such info, but I would suspect that if someone were truly interested, considerable info is available.
Part of the success of the tube fuselage is passenger comfort. Consider that by keeping the passengers within close proximity to the longitudinal axis of the airplane, the passengers on the outside of the rows experience only limited vertical motion during a bank.
For example, the Boeing 777 has a cabin radius of about 10ft. In a 15 degree bank, the passengers in the center seats will experience almost no vertical movement while passengers near the window experience an up or down of only about 3ft.
If we were to go to a flying wing configuration with a 777 wingspan, say about 100ft from the center, our passengers on the edges are now looking at rapid vertical movement (remember, the wing tips have to move faster than the center) of as much as 26-30ft in addition to the forces of the bank. I hope they have strong stomachs out there.
Not that it wouldn’t be cool to see flying wings and blended wings at the airport, but we’ve found a basic design that keeps passengers comfortable and can economically carry people and freight between any two points on the globe. Any radical change is gong to have to provide a significant economic improvement on that before it is accepted by the airlines.
I think the next big thing to watch for will be supersonic business jets. It costs a lot of money to go fast, but there are people willing to pay for it.
sounds like he’s talking about a “canard” wing design, which has been done. the only notable passenger version I can find is the Beechcraft Starship.
I tend to err on the side of “if nobody’s really doing it, there must be a good reason or two.”
Yes, that does look like what he was describing. I’m just a dumb lawyer. He loves to talk about air/space transport, but I am only able to participate on such a superficial level.
IIRC the other problem was coordinated turns. From what I recall reading, if the passenger is too far out from the longitudinal axis, then bank turns will do fun things with their inner ear.
However, the Dreamliner demonstrated there’s a lot of incremental improvement to be made - for example removing miles of hydraulic tubing and putting batteries and actuators where they are needed, replacing metal with lighter, stronger composites, etc.
Canard (wing in back) configuration is valid, but AFAIK conveys no huge advantage over standard design, so the “ain’t broke, don’t fix” rule seems to apply. Plus, the companies recycle a lot of old design into new, so starting with a completely brand new design probably costs more. Not sure what the weight and balance implications of a very large canard design are. Rutan’s designs were touted as “stall-proof”, but IIRC that was done by limiting the control of the canard, so it always stalled before the main wing - safety at the expense of maneuverability. The same has been done with some traditional designs, limit the amount the tail can alter the aircraft angle of attack. The major benefit of a canard is avoiding the problem where the stabilizer ends up in the turbulence of the main wing making stall recovery impossible - but an airliner in a stall position is already well beyond where it should be.
I think the previous posts are right - we’re in a trough before the next big breakthrough. It simply takes too much energy to punch through the atmosphere at aircraft altitudes at supersonic speeds. (If you’re ever in NYC, go to the Intrepid museum and walk through the Concorde - see how tiny a cross-section you need for your aircraft to make $8,000 almost cost effective for a trans-Atlantic flight) The airliner of the future will be hypersonic, jump up well above current air lanes to cross the pacific in an hour or so; the sort of thing NASA is testing right now with models.
Big metal tubes are also super easy to manufacture. They can be made in segments in an assembly line fashion, and the wings can be made on another assembly line. You only need to make room for an entire plane when putting the wing and fuselage sections together. By this point, I’m sure the tooling and handling equipment is very mature and the whole system hums along quite efficiently.
Whoever makes the first blended wing airliner will first have to build an all-new factory, with all-new manufacturing techniques, and all of the expense that entails.
I want to see subway car straphangers installed-that way they can cram even more people in. Standing room only!
How about rear-facing seats?
I think Ryan Air already talked about doing that.
Yes, they should eliminate the seats, put racks along the outside and down the middle, and you walk in and rack your luggage then hold on to the rack. The straps are a good idea instead of seatbelts, the only downside being matching up the hands with the bodies after a crash.