The whole insistence on it being exactly at the whistle board is another thing I find a bit strange. Of course I do follow that rule as much as possible (we do have a number of whistle boards located at the same point as permanent AWS magnets and you can easily run out of hands!) but what if you're going more slowly? We have one just after a bridge with a MU90/40 speed restriction - so depending on the traction on two consecutive days I can be doing twice the speed at the same board!
The whole 'tones at whistle boards' instruction turned into a very political quagmire. Chuck in NIMBY's, Environmental activism, and ASLEF's political diatribe and in all honesty it got "messy" (yes, double inverted commas)
Noise pollution stepped in and we changed how to sound the horn, politics stepped in and we changed again, and some will sound for X+Y seconds. Some will also sound both tones, based on unit, based on policy, based on preference, based on politics. The Rulebook is quite clear when you are required to sound your horn.
@craigybagel the rulebook doesn't specify speeds at the whistle board but the 'at the board' bit is based on 'the science'. When we sounded early, it
MAY have been the case where someone didn't receive the warning in time or didn't get the warning because they simply didn't hear it. I have read too many RAIB reports to discount the minutiae. They go into to find the 'facts' of each specific case. There is a lot of research on Spark regarding why and what we do. TBVFH. 'It's above my pay grade' and I've learned to suck it up and trust in those that know the details.
But yeah.. Isn't it weird that I sound my horn 'randomly' for 'PWay' or because I thought I saw something....
Com.