On 2016\01\11 21:55, Recliner wrote:
Basil Jet wrote:
On 2016\01\10 15:42, Recliner wrote:
Basil Jet wrote:
I was thinking about what a wasted resource the DC lines from Queens
Park to Euston are. A twin track railway to the edge of Central London
with only 3tph. But what to do with it?

You could build a curve from Wembley Central to Sudbury & Harrow Road.
The DC lines are on the west side here, so a flat junction would be fine
and I don't think any demolition would be required. The Marylebone Line
would be expensively interfered with as the new line went under it or
budged it apart and came up in the middle. The Suds and Northolt Park
would become Overground only with a train from Euston every twenty
minutes terminating at a new platform at South Ruislip. The existing
Marylebone trains which semi-randomly call at the stations would cease
to call there and would give an increased service at Wembley Stadium and
South Ruislip instead.

The doubling of frequency of Overground service from Euston to Wembley
Central would probably mean the end of Stonebridge Park terminators on
the Bakerloo, leaving an off-peak service of 6tph LU from Harrow and
Wealdstone, 3tph LO from Watford and 3tph LO joining at Wembley Central.

I like it personally, but is there room in the South Harrow tunnel for four
tracks? I don't believe that the line was ever four-tracked except at some
stations where there used to be platform loops. Those stations would need
rebuilding. Some of the two-track bridges would also need rebuilding, such
as the expensive new one over the A312.

I wasn't thinking of a fourth or third track. Can't a train every twenty
minutes stopping at three adjacent stations share track with the Chilterns?

Chiltern's argument for having so few trains stopping at those stations is
that they get in the way of the far more important 100mph non-stop services
(up to 8tph) on the same tracks. At the very least, you'd probably have to
reinstate some of the platform loops that were removed when the route was
modernised, so that the fast trains could overtake the stoppers.

.... which would have to have 4 minute dwell times to let the fast train
go from 2 minutes behind to 2 minutes in front. That's worse than
Thameslink! Surely part of the problem is that diesels are distinctly
unwhippetlike... an electric overground service wouldn't present quite
the same problem.