Railperf
Established Member
- Joined
- 30 Oct 2017
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- 3,110
The TVM signalling system supervises speed and will intervene with braking over at least 10kph over the permitted speed38 seconds to 60mph
On the contrary, it's perfectly possible.
Now I'm not sure if the 395s themselves have an overspeed limiter, but the TVM430 will allow an overspeed margin of 15km/h at over 160km/h before intervening with a brake application.
Though as you rightly say such methods of speed recording are not 100% accurate, but it's very possible you did touch 141mph, don't feel you have to rule it out straight off the bat!![]()
But data downloads by driver managers keep real speeds to no more than a few kph over the limit.
Due to gradients and speed restrictions over switches and crossings departing and approaching stations - combined with quite steep gradients, it is Impossible to measure a clean 0-140mph acceleration run on level track.