# Why don't airlines load their passengers like freight?

Apparently, the time for boarding and deboarding an airplane is a large cost factor and something airlines try to minimize but have trouble controlling because the passengers do it themselves. A solution would be to have passengers board a passenger cabin outside of the airplane and then slide that cabin into the plane via a nose-hatch, much like large volume freight. Has this been considered? If yes, why was it not pursued?

• Do you really want to treat passengers like cattle? – ratchet freak Feb 1 '15 at 21:33
• Why don't airlines load their passengers like freight? You obviously haven't flown on some of the airlines I have, – Simon Feb 1 '15 at 21:43
• Passengers tend to object to being packed into cargo bins and left sitting upside down by inattentive ground handlers... – voretaq7 Feb 2 '15 at 1:18
• @corsiKa Those kids would be much less of a nightmare if jammed tightly together and packed in a tomato sauce. – David Richerby Feb 2 '15 at 16:33
• I'd be very willing to travel in a 'capsule hotel' type unit if it were the same price as an economy seat, because I'd get to lie down and go to sleep. I wouldn't at all mind it being stacked above/below other capsules. I would need to get out occasionally to go to the toilet though. – A E Feb 3 '15 at 12:53

Boarding takes a long time, true. There are more efficient strategies (.pdf) which have been proven to speed up boarding by between 20% and 50%, still they are not adopted. Why?

You need to load the baggage, too. Also the catering. And fuel. You need to inspect the aircraft, run through checklists and brief the new crew. This all takes up time, too. Airlines do not see a big saving by loading passengers faster, and then waiting for all other jobs to be completed.

Your radical idea of containerizing passenger transport would certainly speed up things, but it would cost a lot of payload.

1. The most efficient pressure vessel is a sphere, and the next efficient is a cylinder with spherical ends. Pressurizing a boxy container is structurally very inefficient.
2. Loading passengers on palettes first and sliding those palettes through a narrow opening takes time in itself. And the palettes have their own weight, their own floor, their own support structure for the baggage racks, their own cabeling for the entertainment system. They would, however, not need their independent pressurization, so their weight impact would be moderate.
3. A possible "flatbed" airliner which could attain the shortest boarding times has only half as much fuselage height (or less) to transmit bending loads along its length. See here for an example of buckling in a fuselage skin due to bending loads. Now consider that reducing height by 50% will need four times more cross section in the longerons to keep stiffness constant. That will make the fuselage much heavier.

In the end, airlines go with the solution which maximizes their profits. By using a hollow cylinder and let their "cargo" self-load, they can maximize their payload and get tolerable boarding times. Tolerable for them, that is. That better loading procedures could allow you to come to the airport later is of no interest to them. If they would see an advantage in shorter boarding times, there would be ample of opportunity by improving strategies, even with existing airplane designs.

• I don't think it's certain that it would speed anything up. Loading a fuselage-sized container into a plane would be a slow, delicate job and I can imagine it taking rather longer than just getting 300 people through a door. – David Richerby Feb 1 '15 at 23:44
• Plus, why would seating passengers into the removeable compartment be any quicker than seating passengers directly into the plane? – user1804 Feb 2 '15 at 4:12
• @PeterKämpf this solution does not solve the problem of passenger who choose to do last minute shopping and arriving late at gate. I did that myself. It is more of a human factor that is limiting factor here. – vasin1987 Feb 2 '15 at 7:08
• @HorusKol The point isn't to speed up the loading time from the passenger's perspective, it's to speed it up from the aircraft's perspective. Aircraft are big expensive assets so the less "dead" time they have on the ground the better. Speeding up turnaround times in general is a big win. – Nigel Harper Feb 2 '15 at 12:11
• @DavidRicherby: You're right - the "hatch" term got me confused. And a Boeing concept from the Eighties of a "flatbed Jumbo". But the point is the same, nevertheless: The airlines don't see a need to speed up boarding. – Peter Kämpf Feb 2 '15 at 16:52

The system you propose would be extremely heavy compared to existing aircraft. More weight means more fuel and more fuel means even more fuel to carry that fuel through the air, and even more fuel to carry that fuel and so on. Fuel is one of the biggest expenses an airline faces.

It would also be extremely expensive. To gain any time, you'd have to have the departing passenger capsule loaded and ready before the arriving passengers have left their capsule. That means you need twice as many capsules as planes.

And the time saving wouldn't be all that great. You'd still have to refuel the plane and load and unload the cargo. Manoeuvring a fuselage-sized capsule into the plane would be a long job. I'm far from convinced that it would be faster than getting however many hundred people through the door.

• More to the point, maneuvering a fuselage-sized capsule full of passengers without jostling or injuring any of the occupants. – Shadur Feb 2 '15 at 11:01
• @Shadur If you were fully committed to the passengers-as-cargon idea, you wouldn't worry about jostling the cargo. ;-) – David Richerby Feb 2 '15 at 16:22
• @Shadur -- well, don't forget, they have to do that with the plane as a whole. – Malvolio Feb 3 '15 at 5:14

The first and biggest concern would be the weight of the container. They need to have walls, floor and a ceiling and be able to lock in place on the plane.

Also each division between containers would remove some room available for another row of seats in the traditional method.

• Don't forget that the most efficient geometry for a pressure vessel is a sphere, followed by a cylinder with spherical ends. The boxy container is impossible to pressurize without substantial deformation. – Peter Kämpf Feb 1 '15 at 23:09
• @PeterKämpf which means that the pressurization must come from the fuselage still, I didn't forget that. It also means that the "nose-hatch" much be strong enough to withstand pressurization. – ratchet freak Feb 1 '15 at 23:15
• @ratchetfreak The nose hatch withstanding pressurization isn't a particularly intractable problem, though. Such aircraft already exist. I don't feel like doing the calculations right now, but it wouldn't surprise me at all if the pressure applied to the outside actually exceeds the pressure being applied from the inside on the front section of the aircraft (which is, obviously, facing the airstream.) – reirab Feb 3 '15 at 6:04

Passenger crates were envisaged a long time ago. Apart from the above objections, may I add this: A passenger crate in a plane is a box in a box. This would worsen claustrophobia which is already a problem. A view outside would alleviate this, but requires windows. Crate windows would need to be aligned with fuselage portholes.

The psychological problem is doubled by a physical problem which is emergency evacuation.

Any project would need a highly standardised crate compatible with competing aircraft types. This standard would later become a constraint for future design innovation. It would also limit customisation of planes by constructors for specific customers.

• Emergency evacuation is a very good point (eject the capsule!!! ;-). But I disagree on standardization, as I don't see why you'd need a standardized crate to get the benefit of a faster turnaround for the main plane. And surely it would increase customization? Most customization these days is in cabin layout but, in this scheme, the cabin is a completely separate module. – David Richerby Feb 2 '15 at 16:37
• @DavidRicherby: To load passenger crates independent of aircraft type and position within the plane will need a lot of standardization: Everything needs to line up correctly, from air ducts to escape doors. Paul has a very valid point here. – Peter Kämpf Feb 2 '15 at 17:01
• @PeterKämpf Yes, to do it independent of plane type would require standardization. But why would it need to be independent of plane type? For example, airports today cope just fine with loading Boeings and Airbuses of various different sizes. Why couldn't they load 777 capsules into 777s, A380 capsules into A380s, etc.? The problem seems to be with the capsule concept, not with different planes taking different capsules. – David Richerby Feb 2 '15 at 17:40

I wouldn't want all of the connections for pressurisation, air conditioning, lighting, water, IFE etc etc connected and disconncted every flight. A maintenance and safety headache.

Something even more radical has been considered! Airbus filed a patent on replacing the entire upper fuselage - seats, passengers and all - during a layover. The structural problems inherent in that idea look pretty hard though.

• This doesn't really answer the question. – SMS von der Tann Feb 26 '16 at 12:54
• "Has this been considered? If yes, why was it not pursued?" Okay, so it slides in from the top/side rather than through the nose, but it's the same idea. – FLHerne Feb 26 '16 at 12:56

My suspicion is that delays in loading passengers onto aeroplanes come from two sources:

1) Security & border concerns since the hijacking of aircraft became common in the 1970s;

2) Airports' desire to make money from passengers being forced to wait in airports, where they buy things from retailers who are paying tenants of the airport.

On the topic of (2) a British airport group (Heathrow is one of their properties) told shareholders around 15 years ago that they were not in the transport business, but in the retail business, pointing out that over 60% of their revenues came from rents paid by airport retailers.

It's elementary economics that while this is the case, airports and airlines have no incentive to make aircraft boarding quicker, even if a solution for (1) were found. Were airports to shift their revenue model away from retail, this entails airlines paying more for landing slots, so the two groups have a common interest in wasting the time of travellers by keeping them in airports for as long as possible out of their travel time.

A saner approach to speeding up the loading of passengers would be - rather than loading them in boxes like freight - to simply cut the airport out and have passengers board special buses in town, check their bags and travel documents with a couple of officials who are also travelling on the bus, and have those buses drive straight onto the tarmac and up to the aeroplane.

This is after all how very rich people travel. Someone drives them straight to the aeroplane.

Airports earning 60% of revenues from in-airport retail tenants are unlikely to support this simple idea, however.

• This answer seems to be subjective with personal opinions. I also highly doubt if your "bus direct to terminal" solution is practical at all. – kevin Feb 3 '15 at 15:13
• I don't think that this is what the question is about. Time lost in the airport does not cost the airline anything, it's the time spent by the aircraft on the ground that is a large cost factor. Your “solution” would actually be worse, from the airline's point of view. – Relaxed Feb 3 '15 at 17:28
• I understand your point, Relaxed, that the question seeks to reduce aircraft loading times, though I'm not sure why bus-loading would be worse. Is it subjective, kevin, to consider who benefits commercially from the current status quo? And why would travellers loaded into a kind of pallet favour airports, since pallets could be transported from anywhere? I'd argue that the bus-to-the-aircraft solution must be more practical: planes can park on a much larger area of tarmac away from buildings. Some airports take passengers to the plane in buses already, so why not drive buses out of town? – Mark Griffith Feb 4 '15 at 12:45
• @MarkGriffith For one thing, busses in town are accessible by millions of people with no security controls at all. Therefore, to maintain the current level of security, they'd all have to be searched thoroughly before being allowed to enter the ramp. Keeping the entire aircraft in a secure area and just checking the bags and passengers is much more cost and time efficient. – reirab Nov 20 '15 at 21:29
• Also, if airliners boarded faster, passengers would, on average, spend more time in the terminal where they could be buying stuff, not less. Passengers can't be buying stuff while they're standing in line in the jetway waiting on the guy in row 3 to shove his bag in the overhead. If boarding took only 10 minutes instead of 20, for example, that's 10 minutes longer people can wait in the terminal before boarding where they could be buying stuff. – reirab Nov 20 '15 at 21:35

I for one would jump at the chance to arrive earlier, "board" earlier and sit in cramped airline seating even longer so the airline can save money.

If you didn't pre-load the passengers in your capsules before the plane was ready to depart, there would be no time savings.

No thanks. It's bad enough they hold you prisoner on the plane when there are hour + long delays in departure.

• That has nothing to do with boarding and everything to do with how pilots and air crew are paid. Basically less or not at all when the plane is hooked into up at the terminal. Pay starts when the door closes. – Rowan Hawkins May 29 '18 at 23:48