On Wed, 17 Aug 2016 09:13:10 -0000 (UTC)
Recliner wrote:
The speed reduction with a high speed train will be trivial. By the time

I disagree. Kinetic energy is derived from velocity squared, so a small change
in velocity can make a large change in the amount of energy that needs to
be dissapated.

So if the obstruction was only 200m away, the train may still be travelling
at full speed. Even if it was 500m away, the speed will probably still be
close to 300 km/h. The driver would be best advised to retreat from the

You're forgetting however that the driver will have put the train into braking
mode. An ATO train would still have full power to the motors at the point of
impact and possibly beyond too. In fact thats what happened in the moorgate
crash - albeit with a suicidal driver and not a computer - with the back of
the train actively shoving the front up over the sand drag.

Where the driver might be needed is during slow speed manouvres near
stations, not the high speed sections of the line.

You'll certainly need a pair of eyes pulling into platforms.

--
Spud