There were 3 S Stock trains stabled in Northfields a few months back, they were there for a fortnight or so. No room for them anywhere else, so i would assume as others have said this is the reason for the current visitor.

You may also notice on the platforms at South Ealing S Stock stopping diamonds.

"Peter Masson" wrote in message
...

Colin Rosenstiel wrote in message
...

In article , d
() wrote:
On a similar note - how far down the piccadilly line towards heathrow can
surface stock venture?

Brake testing at South Ealing? The line was cleared to just short of
Hounslow West IIRC.

Until the early 1960s there were a few District trains which ran to (the old
station at) Hounslow West.

Peter

Its seems very short sighted that they didn't dig full size tunnels to
Heathrow. Now they could have benefited from S7s going to the airport
instead of an undersized tube train.

Kevin

On Wed, 4 Jun 2014 23:53:01 +0100
"Kevin" wrote:
Its seems very short sighted that they didn't dig full size tunnels to
Heathrow. Now they could have benefited from S7s going to the airport
instead of an undersized tube train.

Thats true. It probably wouldn't have cost that much more either even using
1970s technology. I suppose the only issue would be that if the district
served heathrow the trip to central london would be even longer with all
the extra stops between acton and hammersmith.

--
Spud

wrote:
On Wed, 4 Jun 2014 23:53:01 +0100
"Kevin" wrote:
Its seems very short sighted that they didn't dig full size tunnels to
Heathrow. Now they could have benefited from S7s going to the airport
instead of an undersized tube train.

Thats true. It probably wouldn't have cost that much more either even using
1970s technology. I suppose the only issue would be that if the district
served heathrow the trip to central london would be even longer with all
the extra stops between acton and hammersmith.

Yes, and the frequency would be lower, as the Ealing branch is just one of
3.5 (ie, Ealing, Richmond, Wimbledon and sometimes Olympia).