Why the variations in width of (former) SSL stocks?

[Deleted]

A60 stock was 116 inches wide, C69 stock was 115 inches while D78 stock was only 112 inches.  Surely it would have been logical to build all sub surface stock to the same dimensions.

[metman]

The good old days!

The reason is history and the fact that stocks were designed for specific lines. The A stock was quite special. It was so wide to allow 3+2 seating as it replaced the popular compartment stock. As the tunnels on the met were wide enough the trains were built to fit - sadly this did not allow them to run off the Met!

The C stock was built to a relatively standard width. The similar F stock dimensions being an example. The flared stock was a legacy of the removal of the running board.

The D stock is narrow as the cars are longer and have a greater over hang much like the 1973 stock.

[norbitonflyer]

For the same reason that the class 165 diesels on the same route are wider than normal diesels. They were built for two lines which, for rather different reasons*, had a wider loading gauge than most. So why not make the most of it?

*namely Brunel's desire for stability at speed, and Watkin's continental ambitions.

You could of course extend the argument the other way and ask why all (and I mean all!) Underground trains are not built to the same dimensions as 1992 stock.

[rincew1nd]

If D Stock are narrower than C, is it the car length (and consequent end-throw) that prohibits them from the top side of the circle?

[MoreToJack]

Jan 5, 2016 1:25:25 GMT rincew1nd said:

If D Stock are narrower than C, is it the car length (and consequent end-throw) that prohibits them from the top side of the circle?

Paperwork and platform lengths between High Street and Baker Street primarily...

flic.kr/p/x59zNy

[Tom]

D stock are, AFAIK, prohibited on the Northern part of the Aldgate triangle because of passing clearances with other stocks, which probably is due to the additional car length and consequential end/centre throw.

[castlebar]

For some reason I have never had satisfactorily explained, District Stock DID run regularly in service around the top side of the Circle. I think it happened on Easter Monday every year until about 1966/7)POSSIBLY on other Bank Holidays too)and I think services ran around to Aldgate (from Putney Bridge?) but didn't complete the loop. Photos exist as evidence, (somewhere)

[Dstock7080]

Jan 6, 2016 19:56:10 GMT castlebar said:

For some reason I have never had satisfactorily explained, District Stock DID run regularly in service around the top side of the Circle. I think it happened on Easter Monday every year until about 1966/7)POSSIBLY on other Bank Holidays too)and I think services ran around to Aldgate (from Putney Bridge?) but didn't complete the loop. Photos exist as evidence, (somewhere)

As these 'District' Stock at the time, CO/CP, Q and R Stock were to the same dimensions as the incumbent O/P Stock on the H&C.
The main differences came later, with the introduction of the D Stock.

[norbitonflyer]

Jan 6, 2016 19:56:10 GMT castlebar said:

For some reason I have never had satisfactorily explained, District Stock DID run regularly in service around the top side of the Circle. I think it happened on Easter Monday every year until about 1966/7)POSSIBLY on other Bank Holidays too)and I think services ran around to Aldgate (from Putney Bridge?) but didn't complete the loop. Photos exist as evidence, (somewhere)

www.davros.org/rail/culg/district.html

CULG, as always, has the details.

Until 1926 the MDR provided part of the Circle service. From 1st November that year, this was replaced by a extension of the High Street Kensington service to Edgware Road only. Although District drivers continued to operate some Circle services on Sundays until 1990.

But "For many years some of the trains on the Edgware Road service were extended over the Circle Line to Moorgate, Liverpool Street, or Aldgate (usually the latter):
•on Bank Holidays from 1945 to 1953, and again in 1968 and 1969;
•on Maundy Thursdays, Christmas Eve, and the Fridays before Monday Bank Holidays, from 1945 or 1946 to 1953;
•on Saturday during lunchtime (usually to Liverpool Street) and the early evening, from 1968-10-19 to 1972-02-05."

These would all be using O P and Q stock.