Managed Motorways - change of speed limit
Discussion
A couple of times, as I've approached a gantry, the limit has changed in front of me - both higher and lower. When it changes to lower as you approach, what's the lee-way? Are you supposed to brake to reduce speed, or is there a period of grace?
Rather than brake, I've just let my car slow down gradually... I've no desire for a rear-ender by the car behind being distracted by a changing sign and checking his/her speedo... no tickets yet, but bound to happen one day.
Maybe I should gently apply the brakes so the light is on but deceleration is modest? Or would this pitch an unattentive driver behind into a panic?
Is there a period of grace?
Rather than brake, I've just let my car slow down gradually... I've no desire for a rear-ender by the car behind being distracted by a changing sign and checking his/her speedo... no tickets yet, but bound to happen one day.
Maybe I should gently apply the brakes so the light is on but deceleration is modest? Or would this pitch an unattentive driver behind into a panic?
Is there a period of grace?
Retroman said:
If you are traveling faster than the posted speed limit, you are speeding as far as the law is concerned.
You need to slow down before passing the lower speed limit signs or risk a fine / awareness course.
You need to slow down before passing the lower speed limit signs or risk a fine / awareness course.
Obviously I don't know for sure, but I would assume that there would be a few seconds of 'grace' built into the system before enforcement at the lower speed occurs. I've been in the same situation myself a lot. (NSL to 40 in one swoop on the M4 around the Almondsbury interchange).
You know who knows? The Highways Agency 
HA said:
When a mandatory speed limit changes on the overhead AMI signal, there is an automatic one minute delay before enforcement can begin against the newly displayed limit. The flash units can still activate during this period, even though the new limit would not be enforced. In this situation, drivers are not expected to brake sharply, but rather to reduce their speed so that they are within the speed limit as soon as it is safe to do so.
MG Ant said:
Is there a period of grace?
http://www.highways.gov.uk/our-road-network/managi...Edit: Beaten to it!
SS2. said:
MG Ant said:
Is there a period of grace?
I think the minimum as stipulated by the relevant legislation is 10 seconds.HA said:
Where a speed limit changes less than ten seconds before a vehicle passes the sign, the Regulations [the Road Traffic Act] allow a driver to proceed at a speed up to the maximum applicable before the change, and to continue to do so until the driver leaves the specified road, the national speed limit applies or until the next speed limit sign. The intention behind this ‘ten second’ rule is to protect the driver from being prosecuted if, on the approach to a speed limit sign; it changes to a lower speed. For example should a driver approach a speed limit sign and it changes from 60mph to 50mph and he/she is within ten seconds of passing that sign then the driver can legally continue beyond that sign at 60mph until a subsequent speed limit applies or until he/she leaves the specified road. If there was no ten second rule, the issue of safety arises, as the driver would be required to brake sharply in order to comply with the new lower speed limit.
Retroman said:
You need to slow down before passing the lower speed limit signs or risk a fine / awareness course.
Impossible. If a sign changes to a lower limit then there is a finite reaction + braking time. If you are closer to the sign than that then you cannot possibly slow down in time. Also you cannot see the sign above you as you pass underneath. 10 seconds seems quite short given those limitations. Not even considering the fact that you might not be directly looking at the sign as a 6 changes to a 5 but concentrating on more important stuff like the actual traffic conditions.Gassing Station | Speed, Plod & the Law | Top of Page | What's New | My Stuff