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A bigger problem with blended wing designs is actually for the people on the peripheral. When the plane banks, passengers further from the axis of rotation will
by nicktelford 4y ago
A bigger problem with blended wing designs is actually for the people on the peripheral. When the plane banks, passengers further from the axis of rotation will feel a more significant change in their altitude. You literally feel like you're "falling", as the plane banks to your side.
This also applies to existing aircraft, but the amount you drop/rise is limited by the your distance from the axis of rotation, which is normally not very far. In blended wing designs, the distance could be considerably greater, making this sensation much more intense.
The workaround for this would be to simply use shallower bank angles, but I suspect that would require some pretty major changes to navigation rules, as it would drastically increase the turn radius.
- chrisBob 4y agoThe issue isn't the bank angle exactly, it is the acceleration of the roll. Pilots will need to be careful not to throw people or drinks around, but I think it would be doable.
- aaronblohowiak 4y agodepends on the flight paths for different airports. some require tighter turns.
- dan_quixote 4y agoPilots can control the bank acceleration, sure. They have much less control over acceleration due to uneven turbulence.
- thot_experiment 4y agoI'm not sure this tracks, I think turbulence powerful enough to cause passenger discomfort is usually so big that it affects the whole plane pretty uniformly. I think it's exceedingly unlikely that you'll spend enough time on a shear line to induce a large roll. At least it's never happened to me, but I am only a passenger.
- HPsquared 4y agoIn a typical plane in turbulence, you can see the wings bending up and down. Perhaps a blended wing would be stiffer, though.
- thot_experiment 4y agoYes a blended wing would be stiffer, but wing stiffness isn't really relevant here. The wing bending isn't evidence of differential pressure between the two wings, it's only showing that the wings are the part of the plane that's most affected by turbulence while not accounting for the majority of the inertia. The point is that air currents powerful enough to appreciably affect a large plane are large scale and therefore you're unlikely to have enough differential pressure from one wing to the other to impart much torque. I'm not certain about this and I'd love to be corrected if I'm wrong.
- HPsquared 4y agoAh, so in other words the whole plane bumps up and down but doesn't rotate. Therefore the location of passengers doesn't matter much, as all locations experience the same acceleration. (Provided the cabin is stiff)
- gcanyon 4y agoWhen I was younger, watching the wings flex up and down in turbulence was one of my favorite things about flying, like an amusement park ride. Over the years my perspective has changed.
- hindsightbias 4y agoI've been in turbulence with high roll rates and even as a pilot unbothered by moderate chop, it will cause me to sweat. I've been in the last rows of a 777 and watched the fuselage flex in chop. A blended body would be pretty rigid and have a very low wing loading because it's basically all a wing. So it would be pretty uniform. It would work if all turns were managed via controls to be a 1/4g, otherwise riding the outside would be like a roller coaster. I'd prefer to go back to the MD-80. Very high wing loading, fast and never broke down. Skated through turbulence.
- gauravjain13 4y agoTrue, but absolute bank angle would also matter (say endpoint of roll when roll acceleration is zero) because now there's a component of gravity pulling you sideways.
- AnimalMuppet 4y agoNot if the pilot did it right. The net force on you should always be directly toward the floor.
- alistairSH 4y agoEven when the plane is tipped over at 15* (or whatever their max bank angle happens to be)? The floor is no longer directly underneath you.
- orangepurple 4y agoThe plane turns while banking which results in a force vector mostly straight down towards the floor. If the plane did not turn while banking what you wrote is true. The ground is whatever you accelerate towards.
- edh649 4y agoBalanced out by the centripetal force of the plane turning!
- vel0city 4y agoUnderneath is a relative term.
- mannykannot 4y agoIt is called a coordinated turn and it is what one normally aspires to fly. https://www.boldmethod.com/learn-to-fly/aerodynamics/the-aerodynamics-of-a-turn-in-an-airplane/ https://www.boldmethod.com/learn-to-fly/aerodynamics/the-aer... A coordinated turn with 60 degrees bank should be achievable by any airworthy airplane (it requires pulling 2g), and the maximum bank angle for a steady-state coordinated turn depends on how many g you can pull before you run out of control authority, cause an accelerated stall, or reach the airframe's structural limit. Next time you fly, get a beverage of your choice and observe how it behaves. Here's an example, courtesy of the great test pilot Bob Hoover: https://www.youtube.com/watch?v=V9pvG_ZSnCc https://www.youtube.com/watch?v=V9pvG_ZSnCc
- rootusrootus 4y agoI think that would be tough. Out in relatively empty airspace, sure, the pilot can make pretty slow turns. But major airports with multiple runways, other airports in the vicinity, military bases, etc, all put hard requirements on the flight corridor. Sometimes the pilot has no choice but to make pretty sharp turns, and that means a pretty fast roll acceleration.
- hnuser123456 4y agoHow about... more rudder? Of course, more control surface area means more drag and less fuel efficiency. Wonder if a flying wing style craft that has enough rudder to match traditional cylinder fuselages bank-and-yank capabilities is still more efficient.
- Retric 4y agoLateral acceleration is less pleasant for passengers. You don’t want peoples drinks to fall off their tray tables for example. That said there is a fair about of wiggle room so I doubt it’s a significant issue in practice.
- midoridensha 4y agoMaybe they could try inventing a way of keeping drinks from spilling when the container is tipped over... I even have a cool name word to describe it: "lid"!
- Retric 4y agoLid or no lid, it’s still a problem if your drink falls off the tray table. Which is one of the reasons they say to put your tray tables in upright an locked position. But even beyond that feeling like you’re falling out of your seat is unpleasant.
- midoridensha 4y agoAutomakers solved this problem many years ago, by making cupholders that are deeply recessed instead of thinking that cups wills somehow magically stay in place with a very minimal indentation (see the "cup holders" on the backsides of glove compartments in 1970s American cars).
- georgeecollins 4y agoyou could also put the passengers more towards the middle and the fuel / cargo on the tips. Doesn't solve the problem and balance would be tough I imagine.
- bongoman37 4y ago
- codesnik 4y agothey don't have to be shallower, just bank angle increase should be slower than usual.
- aaronblohowiak 4y agothis issue is why the startup in socal is focusing on air freight for their flying wing design.
- giantg2 4y agoI'd image the biggest reason is that risk tolerance is lower for cargo companies than for passenger airlines, and that cargo companies are more inclined to run a subset of their fleet as an "experimental" model vs the consistency that passengers expect. They probably also have the biggest potential gains given there's only so tight you can pack people.
- amelius 4y agoBanking isn't a problem in practice or your coffee wouldn't stay in your cup while standing on the table.
- dublin 4y agoThat's called a "coordinated turn", and it's what airline pilots should be aiming at whenever possible. In a coordinated turn, "down" remains aimed at the floor, regardless of actual bank angle. There's even an instrument (the turn-and-bank indicator) designed expressly to help pilots execute coordinated turns, which are generally considered a mark of a capable pilot in any plane...
- scarier 4y agoI mean, the rise of low-cost carriers has shown pretty clearly that passengers are willing to put up with a lot for cheaper tickets…
- deleted 4y ago[deleted]
- oogetyboogety 4y agoThis "falling" feeling is my favorite part about flying
- aeternum 4y agoIt might be good to have a disincentive for the peripheral window seats. Some also find that feeling of falling / turbulence enjoyable.
- dongobongo 4y agopeople in the center, cargo in the peripherals
- lstodd 4y agomakes evacuaion harder that it has to be
- PicassoCTs 4y ago>This also applies to existing aircraft, but the amount you drop/rise is limited by the your distance from the axis of rotation, which is normally not very far. When a plane is crabbing, as in coming in sideways towards the runway, when it touches down, and suddenly pivots to normal runway directions, even passengers in the rear of a normal plane, might be accelerated hard around the yaw axis.
- fshbbdssbbgdd 4y agoI wouldn’t want that on a red-eye, but it would add some entertainment to a one-hour flight.
- moffkalast 4y agoWould legit pay extra for the fun ha
- q-big 4y ago> A bigger problem with blended wing designs is actually for the people on the peripheral. When the plane banks, passengers further from the axis of rotation will feel a more significant change in their altitude. You literally feel like you're "falling", as the plane banks to your side. This is a problem that a market can easily solve: make the more central seats more expensive than the outer ones. If the pricing is right, the demand for the various kinds/positions of seats will be balanced. P.S. I can actually imagine that there do exist people who prefer the outer seats because they like the acceleration that makes the flight feel more like a carnival ride. :-)
- deleted 4y ago[deleted]
- scottLobster 4y agoTotally on board with flying in the outboard cheap seats, at least for any flight where I don't have to sleep. Flights are incredibly boring aside from takeoff and landing, and I love roller coasters. :) I have a feeling there are enough of us to make it work in the market and still fill planes, just instead of first-business-coach going front-to-back it'll go center-out, like a theater.
- whatiskolnprob 4y agoMan you must like some adventure.
- ordu 4y ago> This is a problem that a market can easily solve: make the more central seats more expensive than the outer ones. There are risks to create a "vomit comet". Think about cleaning bills.
- xwdv 4y agoDoes this mean if a blended wing plane banks hard and you stand up on one side of the plane you could potentially jump your way across to the other side a bit?