I will draw all the conclusions I like on the basis of many years standing on dead-straight platforms all over this country waiting for people to get off Mk3s before those of us on the platform can get on and move down the aisle to reach a seat, as against dwell times on services worked by MUs with 1/3 and 2/3 doors. You can have doors a mile wide at the end of coaches but that still doesn't solve the problem of aisles inside coaches that are one person wide - the pinchpoint doesn't end when you reach the passenger saloon.
And vestibules that size would take up seats aplenty, or you do a Chiltern Mk3 and lose lots of the toilets, which has caused a deal of comment in places, given the length of many journeys being undertaken on their loco-hauled sets. Hardly an acceptable state of affairs on other long-distance routes, I'd suggest.
The key here is to ask "where is the bottleneck"? Do you actually know? I would be surprised if the speed of moving down the aisle is a bottleneck in any vehicle with 2+2 seating. Mark 3 stock is not particularly easy to get on and off, due to the narrow step board. That is probably the bottleneck. Or it may be the existence of a pinch point inside the train, possibly between the vestibule and saloon. To establish the truth of the matter would require the kind of operational research project that was developed during WW2, covering issues such as the machine-man interface. Do you know of any study in relation to the mark 3 problem we are discussing?
Operational research and ergonometrics remained as widespread part of the design process until the late 1950s and then seem to have gone out of use in Britain, as stock such as the class 313 would never have been put into service in the form that it originally appeared. In Scandinavia, the discipline has developed, which is one reason why Scandinavian design is more generally satisfactory: design of the man-machine interface is a big subject at Chalmers Technical College, Gothenburg.
As regards the toilets, there is no necessity to locate them between the entrance vestibule and the saloon. They can go outside, as in the class 158, or in the centre of the vehicle, not an option if wheelchair access is required but a good position from a number of points of view especially in relation to issues like disposal of sewage and positioning of the retention tank.
1/3:2/3 has definite disadvantages from a structural point of view if the bodyshell is a monocoque. It requires large apertures in the bodyshell precisely where it is undesirable to have them. It also limits the options for seating layouts as the vehicle is divided into three compartments, two of them less than 4 metres in length.
--- old post above --- --- new post below ---
So we'll do away with our 23m coaches, have a lovely new 20m coaches.
You aren't reading, are you? I was referring to establishing loading and unloading speeds as a basis for comparison of the two configurations. And 20 metre vehicle stock is still being ordered for some routes, is it not?
How are you getting on with those pie charts showing all the different costs associated with railway operation? It would be really useful to have that information and you seem to have the patience needed to ferret out the information.
