🚀 go-pugleaf

John R Cambron <*cambronj@chesapeake.net*> wrote:
> greg byshenk wrote:
> > John R Cambron <*cambronj@chesapeake.net*> wrote:

> > > I under stand that more doors = less crowding and faster loading and
> > > unloading that will = shorter dwell times. Their is one problem, the
> > > base WMATA car design like the bart car has a flaw that will not
> > > easily make it possible to add more door without making the cars
> > > heavier. The flaw is the car body it an interracial part of the
> > > structure the car. Punching more holes in the car sides for door
> > > would require beefing up the under fram to compensate loss of body
> > > structural integrity. You got to remember that these car were built
> > > like cabin of an passenger jet airplane, and out of aluminium to
> > > boot. Frankly I think the more traditional way of building of
> > > passenger railroad car would have been a better choice. Stainless
> > > steel car body on a an undercarriage bearing all of the loading and
> > > buffering.

> > I'm not sure whether this is a big issue -- how common is it to change
> > the door configuration of existing equipment?  It seems to me that
> > doing so would be rather a large undertaking -- regardless of whether
> > the equipment is body and undercarriage or unibody construction --
> > and that such configuration changes would normally be made at the time
> > that new equipment is ordered.

> The issue is not to retrofit existing car with more door, it's
> building new cars with more door using the the same car body
> structural design.

I'm hardly an export in this area, but I suspect that a significant
redesign would be involved no matter what body design was originally
used.  It is not just a matter of chopping a new hole in the side of
the car, I don't think.


> > Also, I suspect that adding more doors would _always_ make the car
> > heavier, no matter what type of construction is used, because the
> > doors and their associated hardware will be heavier than the simple
> > walls they replace.

> That is quite likely to be true, but stainless steel is pound for
> pound stronger then aluminium in this kind of application. 

I have no idea whether or not this is true (I suspect that it will
depend on how you define "this type of application").  More
importantly, I don't see how it is relevant; after all a unibody _or_ 
body-on-undercarriage design can each be made of aluminum _or_ steel.


-- 
greg byshenk  -  gbyshenk@byshenk.net  -  Leiden, NL
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