Traffic light sequence

[curvature]

Not sure where to post this so will try here first.

There is a crossroads near where I live and I think the timings of the lights are not quite correct.

I have noticed that a few cars turning right looked like they must have driven through on red but now it seems that the timings are just too close together as I turned right last week and went through when on green but noticed that the cars coming towards me after I had started moving. A friend has also experienced this.

Is it the highways agency that I report this to?

[pills]

Local council website, look for roads and report a problem section.

[blueg33]

Depends on the road.

Trunk roads likely to be Highways Agency, urban roads likely to be County Highways Dept or Council is you are in a unitary authority.

[rdjohn]

In the basic architecture of traffic signal controllers there are safety interlocks that prevent green - green conflicts.

Once a vehicle has passed the stop line it is permissible for it to continue, providing it is safe for the driver to do so.

It is unlikely that the OP is seeing something that has not been designed into the sequencing of the signals.

[SteveStrange]

pills said:

Local council website, look for roads and report a problem section.

This is the correct answer.

[Shappers24]

curvature said:

Not sure where to post this so will try here first.

There is a crossroads near where I live and I think the timings of the lights are not quite correct.

I have noticed that a few cars turning right looked like they must have driven through on red but now it seems that the timings are just too close together as I turned right last week and went through when on green but noticed that the cars coming towards me after I had started moving. A friend has also experienced this.

Is it the highways agency that I report this to?

One of the biggest constraints on the capacity of traffic signals is what’s known as the ‘inter green’ time, which put simply is how long a gap there needs to be between one signal going red and the conflicting signal going green. It’s calculated as the time taken for a vehicle to clear a conflict point should a vehicle pass through at the very last opportunity before red, and and opposing vehicle having a green signal.

In the case of busy junctions it’s not unknown for the signals to be ‘tweaked’ to run the bare minimum inter green time, as this time is effectively ‘wasted’ signal time during the phases.

Oh and without wanting to sound like an a$$ but it hasn’t been Highways Agency since ~2015, when it became highways England, and last year they had another rebrand to National Highways. In any event as posted above, any local road issues should be passed to the Local Highway Authority. If you really want to make an issue of it speak to your local councillor. They love to hound highway authorities on ‘safety’ issues.

[blueg33]

I always forget Highways Agency became Highways England. The still use signs that say Agency around here.

[SteveStrange]

blueg33 said:

I always forget Highways Agency became Highways England. The still use signs that say Agency around here.

National Highways now.

[blueg33]

SteveStrange said:

blueg33 said:

I always forget Highways Agency became Highways England. The still use signs that say Agency around here.

National Highways now.

FFS. Wonder how much money is wasted changing the name!

[donkmeister]

rdjohn said:

In the basic architecture of traffic signal controllers there are safety interlocks that prevent green - green conflicts.

Once a vehicle has passed the stop line it is permissible for it to continue, providing it is safe for the driver to do so.

It is unlikely that the OP is seeing something that has not been designed into the sequencing of the signals.

It seems logical that a traffic light system should be engineered as a finite state machine, but it seems to be untrue. Why, I couldn't tell you. Might be a valid engineering reason, might be stupidity.

I've seen it firsthand. About 15 years ago I turned right at a traffic light controlled junction into a supermarket car park, and ended up with me and a guy coming out of the car park, both having to avoid each other and each accusing the other of jumping the lights.
When I came out a little later I was more wary, and found if I'd pulled away normally I'd have ended up in the same position of conflict as the other guy when I went in.
At work the next Monday various other people mentioned it at the coffee station (anything from "bit dodgy, so I emailed the council to report it" up to "it... Was... CHAOS!")

[Granadier]

Shappers24 said:

In the case of busy junctions it’s not unknown for the signals to be ‘tweaked’ to run the bare minimum inter green time, as this time is effectively ‘wasted’ signal time during the phases.

In my area, the council seems to take the opposite approach, slowing down the phasing to restrict traffic capacity. At many junctions you noticeably spend much longer waiting at a red light than at the same place 10 or 20 years ago. The green phase sometimes lasts just long enough for three vehicles to get through. This fits in with their other policies such as making the borough a 20mph zone, reducing the number of lanes in some of the town centre roads, planning to close main car parks...

[Type R Tom]

Granadier said:

Shappers24 said:

In the case of busy junctions it’s not unknown for the signals to be ‘tweaked’ to run the bare minimum inter green time, as this time is effectively ‘wasted’ signal time during the phases.

In my area, the council seems to take the opposite approach, slowing down the phasing to restrict traffic capacity. At many junctions you noticeably spend much longer waiting at a red light than at the same place 10 or 20 years ago. The green phase sometimes lasts just long enough for three vehicles to get through. This fits in with their other policies such as making the borough a 20mph zone, reducing the number of lanes in some of the town centre roads, planning to close main car parks...

Or could it be they have given more time to pedestrians? There is only 60 seconds in a minute and they have to be shared.

[Turbobanana]

Something I've noticed seems to have changed over the years is people's interpretation of the lights.

Consider the normal light sequence, and what appears to go through people's heads now:

Red - stop
Red & Amber - go
Green - go
Amber - go
Red - stop, if I have to

Couple that with the "performance on demand" nature of a lot of today's cars, and you get all sorts of chancers going early / stopping late.

Linford Christie used to talk about the start of a race, and going on the "B" of the bang from the starter's gun. Now it seems people go on the "A" of the amber and stop on the "D" of the red. Also, I believe the HC no longer says to apply the handbrake and put your car in neutral when you stop, so most people are much more "ready" to go and hence no longer looking at the intersecting lights to see when they're about to change. Or drive automatics, which nobody ever put into neutral anyway.