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Disadvantages: what do you do with traffic signaling? You would either have to move traffic signals up and sideways five meters or so or make this bus a few meters higher, so that you can keep existing infrastructure.

Also: this thing being wider gives it about three times the floor area relative to a train, so it would require about thrice the number of doors to get passengers in and out efficiently. How do you do that while keeping it structurally safe? I guess the answer is that that spacious room inside would see a few walls added.

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> Also: this thing being wider gives it about three times the floor area relative to a train, so it would require about thrice the number of doors to get passengers in and out efficiently. How do you do that while keeping it structurally safe? I guess the answer is that that spacious room inside would see a few walls added.

That thing has already twice more doors than a train since the doors of both sides can be used, so it partially solves that problem already.

The other issue is the type of door they're proposing. The video showed a large elevator being raised and lowered from an elevated platform. That seems unnecessarily slow and complicated, but there's no easy way to get passengers out of an elevated bus above traffic

> Also: this thing being wider gives it about three times the floor area relative to a train, so it would require about thrice the number of doors to get passengers in and out efficiently.

Not exactly. Longer stopping times are enough to get people off and on.

> How do you do that while keeping it structurally safe?

There are no possible structural issues. In fact, building this sort of bus is more trivial than a regular bus, as size and weight constraints aren't nearly as important as regular buses.

"Longer stopping times are enough to get people off and on"

They also may be enough to annoy people so much that they will avoid this like the plague. Extreme example: if this loads and unloads like an airplane and makes a stop every few miles. Yes, maybe only 5% of passengers would get out and in at every stop, but that still would be a one minute stop every two minutes or so.

And if there are no structural issues, why do trains have so few doors nowadays? I would think stops could be a lot shorter at peak hours of trains had more doors.

> Extreme example: if this loads and unloads like an airplane and makes a stop every few miles. Yes, maybe only 5% of passengers would get out and in at every stop, but that still would be a one minute stop every two minutes or so.

That's a good point. I'm sure the bus operators programmed the bus' route to make it at least as good as regular trains with regards to the basic performance metrics such as average operational speed.

> And if there are no structural issues, why do trains have so few doors nowadays?

In short, design options. If a railway operator felt a demand for passenger wagons with more doors and a reduced number of seats, it would be trivial to design one. There are downsides to this (less seats, more moving parts, more maintenance, potentially heavier wagon, harder ticket control, etc...) but nothing stops anyone from doing a passenger car with doors everywhere.

In fact, this was already done in the past.

http://citytransport.info/PhotoCD/PCD13a_098a.jpg

The picture you link to is probably exactly what the original author had in mind. It has mostly wooden bodywork and a metal subframe which in the event of a collision is given to riding up onto the carriage in front and killing everybody. They were literal death traps.

In practice there were half a dozen non-structural reasons to move to less doors including automatic doors being much safer, disabled accessibility and simply that those trains were cold.

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