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Clearance diagrams

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Clearance diagrams
Posted by oltmannd on Friday, May 23, 2014 8:18 AM

Found this image.  Might help sort out some of the discussions we've had from time to time here.

Those bi-levels in Germany, Belguim, Netherlands and elsewhere are generally UIC B (GB).  Notice that they nearly fit within AAR std pass car and are well within AAR plate C which just about universal in the US.

-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/

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Posted by Deggesty on Friday, May 23, 2014 11:08 AM

That looks like a plateful to me.Smile

Johnny

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Posted by blue streak 1 on Friday, May 23, 2014 1:04 PM

How are these clearance diagrams based on clearances around curves ?  Do the diagrams determine the inside of a curve with wheel base ?  Or are curves built with clearances based on their degree of curvature and various plate car's wheel base ?

Some station tracks are quite tight and of course car rocking also has to be considered ?

PDN ?

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Posted by oltmannd on Friday, May 23, 2014 1:42 PM

blue streak 1

How are these clearance diagrams based on clearances around curves ?  Do the diagrams determine the inside of a curve with wheel base ?  Or are curves built with clearances based on their degree of curvature and various plate car's wheel base ?

Some station tracks are quite tight and of course car rocking also has to be considered ?

PDN ?

The diagrams are what they are.  The clearances on the ROW have to be maintained to allow the equipment.  Effect of most mainline curves is very small.  A cushion is maintained to take care of slight shifts over time, rocking, etc.

-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/

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Posted by BaltACD on Friday, May 23, 2014 4:52 PM

Deggesty

That looks like a plateful to me.Smile

Click on it and it can be blown up to make the writing understandable - still a lot of plates in one location.

Never too old to have a happy childhood!

              

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Posted by erikem on Sunday, May 25, 2014 1:07 AM

I was impressed with how big the California recommended clearance requirement is. Maybe the CPUC has a few people who can think.

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Posted by Paul Milenkovic on Monday, May 26, 2014 8:10 PM

Alan Cripe of the United Aircraft TurboTrain and first-gen RoadRailer fame had a "Fastracker DMT" Diesel Multiple Unit Train proposal where he was going to make the cars wider.

Cripe had patents and proposals for articulated trains with single guided axles (the current Talgo, not a Cripe design, is the last remaining train with that feature), and as with the Talgo, the individual train cars are shorter to stay within axle weight limits.  The idea was if you had shorter cars, there would be less over and underhang on sharp curves, and you could make the train cars wider.  I believe he was suggesting 11 feet 6 inches.

Wider is better.  We have had this discussion before, and the tight seats as to both leg room and width characteristic of motor coach buses and of airliners is an economic decision rather than intrinsic to those modes, but the general sense is that trains are roomier.  If you go four across, the extra inches of elbow room you get on a train are an advantage over the other modes, although I point out that the original Shinkansen had 5 across in coach and that in Japan they have some "wide body" trains where they seat 6 across.

But under US conditions and traditions, a train is probably going to be 4 across in coach, but a wider train could offer more comfort.  Maybe you could use this for more elbow room, or maybe you could go to a 1-2-1 twin-aisle seating?

So with the idea that wider is better, the British have historically had a rather tight loading gauge, and Don Oltmann was commenting that there is a little bit of a more compact feel to their trains.  The Continent has had a slighter wider loading gauge, but has the fact that the Talgos are 9 feet 6 inches across (even the Americanized ones -- I checked the dimensions of Talgo 8 on the Talgo Web site), has this entered into any considerations?

10 feet across is a kind of standard, but the Amfleet coaches that are often disrespected as feeling cramped are 10 feet 6 inches.  I think they get that with that oval rather than squared off cross section?  Is 11 feet or even 11' 6" a possibility with a short enough wheel base (as in articulated trains, either Talgo or TGV style)?  Could you get that with an Electroliner-style "fishbelly" cross section?

If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?

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Posted by erikem on Monday, May 26, 2014 9:13 PM

IIRC, the original Douglas "tubeliners" (i.e. DC-4, DC-6 & DC-7) were 10 feet in diameter, the original 707 was also going to have a fuselage diameter on the order of 10 feet, which was increased to 12 feet to allow for 6 across seating in coach. 2-2 seating in a 11' or 11'6" wide car would be like first class seating on the Boeing narrow body airliners.

As for 1-2-1 seating vs 2-2 seating, I suspect ADA requirements would favor the 2-2 seating with wider aisle for wheelchair access. The Pacific Surfliner bi-levels have 1-2 seating on the lower levels presumably to give wheelchairs enough aisle width and the handicapped toilet is also on the lower level.

I'd guess that 11' should be doable with a fishbelly cross section for routes outside of the NEC. You're right in that the Metroliners/Amfleet have somewhat of an oval cross section.

- Erik

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Posted by daveklepper on Tuesday, May 27, 2014 3:50 AM

So do M-1 and up MN and LRR mu's.  Slightly less oval than Anfleet however.

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Posted by timz on Wednesday, May 28, 2014 12:58 PM

All? US main line passenger cars are 120 inches wide at high-platform level (say 48 inches above top of rail). Probably that's overall-- any handholds on the side of the car (and bulgy sides) that make it wider than that are more than 48 inches above the rail.

I'm guessing that includes Acela, but never measured it.

Comets don't bulge, but their 126-inch width ends just above platform level.

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