metman
Global Moderator
5056 05/12/1961-23/04/2012 RIP
Posts: 7,421
|
Post by metman on Nov 9, 2008 20:36:44 GMT
It was recently noted in one post that Metropolitan Trains could use all four platforms at Aldgate to reverse. This photo www.piccadilly-line.org.uk/cstocka.jpgshows the pointwork to do it. When did this pointwork into platform 4 go? |
|
mrfs42
71E25683904T 172E6538094T
Big Hair Day
Posts: 5,922
|
Post by mrfs42 on Nov 9, 2008 21:45:07 GMT
With effect from the 25th January 1988: At Aldgate, the crossover between the two Inner Rail roads at the Liverpool Street end of platforms 3 and 4 (19A and 19B points) will be removed. Train movements from the Outer Rail to platform 4 will no longer be possible. Reversals from Inner Rail to Outer Rail or into the bay road platforms will be possible by new signal OB4. There will be no route from signal OB4 to platform 4. The existing catchpoints south of platform 4 on the Inner Rail will be removed. Oops, forgot to say that this was when the Signalbox was closed at Aldgate and the new IMR was commissioned. |
|
Ben
fotopic... whats that?
Posts: 4,282 
|
Post by Ben on Nov 10, 2008 1:14:51 GMT
Was this just a cse of an economy being made at the expense of flexibility?
|
|
mrfs42
71E25683904T 172E6538094T
Big Hair Day
Posts: 5,922
|
Post by mrfs42 on Nov 10, 2008 1:48:15 GMT
No; sensible interlocking design decision. EDIT: (plus consultation with the TT Office  ) My *personal* opinion is: The route lever for that bit is already at the limits of the capability - add another lever then you get 11 more spares. (notwithstanding the 6 already provided). |
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 10, 2008 7:05:47 GMT
Was this just a cse of an economy being made at the expense of flexibility? There is also the issue of complexity vs equipment reliability to be taken into account. A more complex layout may allow for more flexibility, but may be also more likely to break! |
|
|
|
Post by tubeprune on Nov 10, 2008 9:01:26 GMT
Was this just a cse of an economy being made at the expense of flexibility? There is also the issue of complexity vs equipment reliability to be taken into account. A more complex layout may allow for more flexibility, but may be also more likely to break! And in 6 years of working through this station I never reversed in 4 and never heard of anyone who did although I did reverse in 1 once. |
|
TMBA
you like images? check this out - http://www.flickr.com/photos/upminsterthroughtheyears/sets/
Posts: 364
|
Post by TMBA on Nov 10, 2008 13:12:46 GMT
When the Signal Box at Aldgate was open 8 car A60's reversed in platform 4 and 1 on occasion.
There were the usual problems with this of course, reversing in platform 1 meant that the west end points had to be thrown to Tower Hill to enable an 8 car to fit into platform 1 and of course this shut the district line down until the move had been completed.
There was an incident in 1981 where an 8 car was put into platform 1 with the west end points were thrown and whilst the driver legged it down the other end to complete the move the signalman took an emergency release and threw the points back under the train, the train then moved through the points carrying out the move and continued without damage to itself but left smashed points and severe delays on the district and met.
Reversing in platform 4 was the better move obviously but it had its faults like platform 1 it shut the circle line down and usually there was a circle line waiting at OB38 ready to come into Aldgate and of course this then shut the district down.
To prevent the A60 going to far in platform 4 whilst reversing there were a set of trap points to protect the district line just in case of overrun.
So all in all platform 4 was the better move but it wasn't done that frequently for obvious reasons.
Hope this helps TMBA
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Feb 3, 2009 16:11:45 GMT
There is also the small issue of four services meeting at Aldgate Junction.
|
|
mrfs42
71E25683904T 172E6538094T
Big Hair Day
Posts: 5,922
|
Post by mrfs42 on Feb 3, 2009 18:49:41 GMT
There is also the small issue of four services meeting at Aldgate Junction. Of course, trains are run for passengers, you know! Aldgate and Aldgate East actually manage very well considering the service density - is it still the busiest triangular junction in the world? |
|
)
