When drivers are able to blame having incidents on it, I'm sure common sense will prevail. I just cannot understand what the risk is on GWR?!!! Doing 128mph is not going to cause any harm if it happens, there is zero risk of serious overspeed on ATP fitted lines. I get it on the ECML but not at all on the Western.
Yes, the electric sections of the GWML are already protected adequately by ATP. On diesel, the IET's need to be going downhill to reach 125mph never mind 145!
As I understand it this will be a 'soft' limiter that stops the train accelerating beyond 200 km/h even if full power is being applied? So no brakes coming on! ATP does indeed apply the brakes when the ATP limit is exceeded (131mph?) and the driver doesn't adjust his speed to keep it within the braking curve.
Before IET, we had noted that it had become rare for GWML HST's to run at more than 122-123mph due to drivers staying below the ATP threshold - especially on train sets with worn wheelsets.
And where IET's do reach 124mph they do so far quicker and can maintain that speed consistently. But it does appear different TOC's have different policies about whether or not to use speed set - which do have implications on drivers reliance on these aids. On GEML for example - Norwich drivers do seem to use speed set more - whereas a WA driver i recenlty spoke to said he was instructed not to use it! The result is variable speed running well below the line speed limits in some cases.
Of the recent 'overspeed' incidents - the Lumo train travelling at higher speed over a low-speed set of point caused passenger injuries - whereas the TPE train running at 140mph+ on straight track on green signals caused a delay by the driver having to be relieved of his duties at the next station.
Of course the 145mph story looks far more sensational - even if it posed no risk. The trains are designed for running at 140mph - and components have to be proven to run at a tolerance of 10% over that.
Some might argue that the powers that be sanctioned high-speed running to advertise the launch of IC225 - running at 150mph over the very same railway. So why the sudden knee jerk now! Post Hatfield - the feeling is that the railway is a much safer place to run at higher speeds than it was in those days
You can argue that a simple software modification against the non-ATP fitted IET fleet is a simple and relatively cheap solution that prevents it happening in future and is a sensible decision. Possibly a limiter of 205km/h might have been more sensible from an operational point of view.
TGV's, Eurostar and Class 395 all operate with a 10 km/h limiter above the speed limit - so the brakes won't kick in until the higher limit is reached. Let's remember that it is strict TOC policy for drivers not to exceed the indicated limits by even 1mph - and that is seen in practice.
The real issue however is what will be done to prevent a Peterborough Lumo situation happening again.? ETCS will eventually solve the problem there - but in the meantime - the costly solution will be fit some short term system possibly a newer version of ATP (compatible with upgrade to ETCS) that can prevent dangerous over-speeding in any situation.
So the fleeting 126/127mph will never happen again, but every time a train approaches a junction where a much lower speed applies there is still no consistent system across the network to kick the brakes in and enforce the limit.
In terms of running times, there are many instances of trains running between Paddington and Reading recording slower running times than the HST's they replaced. Some of that is down to infrastructure issues, signalling issues, different driving styles etc and late running trains. At Paddington and Reading there are different approach speeds that apply depending on what platform is being used, and how close you might be to the train ahead.
More time can be lost to those factors than 1mph above or below the speed limit. Recently - IET's were having to run on diesel between Paddington and Reading - that alone cost several minutes per train delay.
But where the limit is 125mph - then the train should be able to run at its maximum and the track maximum of 125mph - not be limited to 124mph. I and many others consistently find that trains lose time to their schedule where they do not run at their maximum permitted and the track speed limit. That applies to varying speed limits across the network.
How soon before we start lowering the limits to several mph below the actual limit just in case a train going downhill 'speeds'?
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