London Banter - View Single Post

Colin Rosenstiel · April 30th 07, 11:46 PM posted to uk.transport.london

In article ,
(Jack Taylor) wrote:

Boltar wrote:
On 29 Apr, 16:25, Steve Fitzgerald ] wrote:
St. Mary's Curve is indeed double track but due to the sharp
curves, the signalling has been modified to only allow one train
in the section at any one time due to the possibility of trains
touching each other.

That begs the question of why did they build the tunnel that bit
too narrow?

Or the stock that bit too big?

Seriously, though, 'A' stock was not around when the curve was
built. The length of modern cars and the distance between the
bogies means that the centre of the vehicles swing further out when
curving than earlier short wheelbase stock would have done, with
the resulting danger of scraping trains passing in the other
direction. 'A' stock was never intended for the ELL and only really
ended up there as a result of their being some flexibility in the
fleet during a recessional period.

Hmm. Wasn't the ELL stock at the time the A stock was built the F stock?
That was pretty close to the A Stock in dimensions wasn't it? I think St.
Mary's Curve was sized for steam stock.

--
Colin Rosenstiel