On Wed, 24 Jun 2020 16:54:45 +0100, "Clive D.W. Feather"
wrote:

In article , writes
Don't know if this has already been posted:

https://www.dailymail.co.uk/news/art...nched-commuter
-train-going-wrong-way-London-Tube-line-nearly-crashes.html

How on earth can this happen?

Possibilities based on what I can see:

(1) Met train is heading for Chesham, the points are therefore set to
cross over, and the Chiltern train SPADed.

This seems the most likely to me. They are reporting that a set of
points was damaged, which would have happened when the Chiltern train
trailed through them.

The LU trainstop would have been at the stop signal, which is (Google
satellite map) close to the facing turnout which sent the Chiltern
train onto the wrong line.

Because the line was equipped with trainstops, not AWS, the driver
would not have had a warning at the distant signal, but he was
probably slowing down for the station.