TheOneKEA wrote:
Peter Masson wrote:

If a stopping train is let out of Marylebone in front of a fast,
the first opportunity for the fast to overtake is Princes Risborough.
In the up direction there are overtaking opportunities at High
Wycombe (where the down platform line is reversibly signalled), and
at West Ruislip (using the Up Platfrom Loop).


This is one of the reasons why the restoration of the through roads at
Beaconsfield and the down platform loop at West Ruislip was
investigated; this would have provided additional passing places on the
Chiltern route south of Aynho Junction. Unfortunately, Chiltern has
since found that adding such infrastructure is not necessary, and have
instead chosen to thoroughly resignal the route north of High Wycombe
and provide bidirectional signalling on both roads between Princes
Risborough and Bicester North.

Where did the fourth track originally fit through West Ruislip? The
present station layout only permits three between the two current
Chiltern platforms.


--
Dave Arquati
Imperial College, SW7
www.alwaystouchout.com - Transport projects in London