[admford]

Interesting article, but there are some flaws in the author's reasoning.

1. Containerizing passenger space.

Not a good idea, it would require a massive re-engineering effort in the structure of the cabin, since a whole tube is a much more reliable pressure vessel rather than half of one with a 90 degree angle where the floor meets the wall. You generate a ton of stress at those joints with pressurization cycles. Hard angles were in part what doomed the first generation of De Havilland Comets. You can possibly add a smaller, whole tube in the cabin area, but then you get the space of a narrow body aircraft & increase weight.

Reinforcing the rest of the structure of the aircraft if you remove the cabin area would also add in a ton of weight. We all know how a cylinder of paper can support many times its weight in compression, cut a big hole in one side and it will collapse. The survivors of Aloha Airlines Flight 243 didn't know if the floor structure of the 737 alone would be strong enough to survive a landing without having the plane break in two.

2. Meshed chairs.

The FAA requires that all aircraft chairs withstand a 16G impact in order to keep passengers safe. There's a reason why the seating is so heavy and bulky, it's to keep us safe during an accident. The seat structure absorbs most of the impact, so our spines and legs don't. Mesh chairs may be cool (both figuratively and literally), but I doubt they'll hold up to 1.5 tons of impact force (16 times the average weight of an American male, 191 lbs) without tearing.

3. Noise

The 787 is heading in partially the right direction to reduce cabin noise. Other than the air rushing by the plane, most noise is from the air conditioning units, and general vibration of the structure. Most planes use bleed air from the turbofan to pressurize the cabin. Basically you take some of the hot air from the compressor stage of the engine and send it through different parts of the plane (to the wing leading edges for de-icing as an example). A good part of this superheated air is sent to the airconditioning units which work to cool it down and direct it into the cabin. The 787 eliminates bleed air completely, and uses other means (mainly electric alternatives) for most systems. Additional insulation & physical isolation of parts that can induce vibrations into the structure also help.

[tass]

Regarding containerizing passenger space:

Rather than having it as a container, what about an open space that is inserted rather than becoming part of the external structure?

So, seating would be arranged on a completely open, flat structure; a long version of this: http://image.made-in-china.com/2f0j00PeRaHYmFgBgL/Retractabl...

Then, this is inserted into an aeroplane, in a manner similar to what you see here: http://www.abi.gr/system/assets/000/000/189/original_cargo_a...

This means the seating platform doesn't need to be pressurized and the required aircraft is already in production.

[larrydag]

I was thinking the exact same thing. I was envisioning a "pod" system that you could have about 10 rows which could hold about 40 to 80 passengers each. Each pod would be a cylinder that could be delivered to the aircraft on the tarmac upon boarding. On disembarking they would be delivered to the jet bridge in a sort of star arrangement where you could have 3 to 4 pods attached at any given time.

This system would be interesting because you have effectively detached the aircraft from the passengers. The airline need only deliver pods to airport destinations. This would create an entirely new supply chain and offers more flexibility in scheduling. Plus the added bonus of decreased boarding and disembarking because all the aircraft needs to do is load pods.

I think there is a lot of merit to the containerization approach.

BUMP: Found this link on the subject http://innopedia.wikidot.com/multi-modal-passenger-container...

[admford]

The problem with a pod system is weight and complexity. Generally speaking, you'd need to create at least two pressure vessels (main cabin, and cockpit), which would have to be joined by a hermetically sealed passage.

Between the inner pod, and the outer skin, you'd need to make sure that doors would work in almost any condition. Sure, you can blow the bolts holding the tail on and use parachutes to make the pod descend, though without the pilots since they're in a separate pressure vessel. But what if there's a fire when the plane is on the ground? Parachutes won't work in that situation, and neither would ejection rockets (unless you want to crush the passenger's spines by launching a multi-ton pod high enough for parachutes to deploy).

The main problem facing airlines is simple. How to pack in as many people as possible onto a flight in order to cover it's costs (airport fees, fuel, food, wages, etc.). More people who can cover the flight's costs means more profit for the airline, or lower costs for the passengers.

The real question with the Pod idea is this. Either way people have to board through a door and go to their seats, so that remains the same. But consider this, would people have to board a pod immediately at the gate, or would they wait in a lounge until the plane arrives? Because if they board the pod immediately, it may save time, but passengers will be sitting in cramped seats, with only airline food, and the limited toilet facilities available for possibly HOURS (if the plane is delayed or the flight cancelled in the end. Since these passengers are not physically ON the plane, the passengers' rights would be questionable in these situations.

Technically you could also fill out a pod and have it wait in a holding area on the airport tarmac while the plane arrives, freeing up gates for other airlines. But this impacts the airport retail system (restaurants & stores), which all pay rent to airports. If you eliminate passengers waiting in gates, you eliminate the need for retail. You eliminate retail, you make it that airports would increase fees for airline operations at the airport. And in the end, it would impact ticket prices negatively.

[Fundlab]

Is that an antonov?

[tass]

Looks like it. Antonov An-124.

[judegomila]

So some good design problems to tackle.

1. Can we make cylinders with lightweight materials with sockets to join to the main plane. It doesn't have to be container boxed shape to be containerized.

2. Can we make Aeron style chairs withstand 16G. A kelvar mesh might be able to hold this G force. I'm not suggesting strapping actual Aeron chairs in there.

3. Good data. Looking forward to testing out the acoustic engineering on the 787

[admford]

1. You can probably design a cross structure that would hold cabin cylinders as so:

O|O --- O|O

But it creates a problem. The surface area of an A380 is about 1009 mˆ2 (45 meters long, 7.14 wide). If we use four 727 (a narrow body airliner) as models for the cabin tubes. The surface area of one tube that size is 537.2 mˆ2 (45 meters long, 3.8 wide). Multiply the result by 4 tubes, you get 2149 mˆ2. That's an increase of 213% in surface area.

Given the structural reinforcements within the host aircraft, the need of aerodynamic surfaces to make sure four interlocking tubes don't create dangerous aerodynamic forces & stresses, and the fact that just for the outer covering, the weight of the tubes increases twofold over a standard A380. A minimum reduction in weight would have to be at least by 50%, if not more in order to be competitive. The 787, with a fully carbon fiber fuselage and other weight saving methods reduces weight by 20% at most over a comparative aluminum structure (http://www.boeing.com/commercial/aeromagazine/articles/qtr_4...).

At this point, the use of separate cylinders to hold people and cargo is more or less moot since the weight reductions needed aren't currently possible (physically, or economically), even with the newest materials.

[epmatsw]

Regarding 2, I'm not sure I'd want to see the results of pressing a human at 16g against a kevlar mesh, especially considering it's mainly our squishy bits that'd be up against it.