traffic-light-man wrote: ↑Fri Dec 16, 2022 15:55
The ambers are both part of the intergreen calculation, so in most cases you wouldn't gain any green time from the removal of the SA as it would need to be replaced with additional red time, you'd just often end up with more lost time when the green does eventually appear. It's more about drivers reacting to the change of the signals than the performance of the vehicle.
Though of course plenty of other places seem to get on fine without it...
Jersey definitely follows the traffic light timings of a UK manual rather than an Irish or French manual (which would probably be more appropriate). As people don't start to set off until the green light shows - unlike the UK where they are already off by the time the green shows - you could probably make the intergreen a second or so shorter and it'd still be safe. Furthermore, the sensors are set up to UK standards, which means at night if you're approaching a light, it won't change until just after you've stopped (whereas in the UK you'd see the amber and be able to continue).
Of course, some people, myself included and my old driving instructor, have learnt the light sequences off by heart. The lack of hoods make it easier to watch lights on the other road and the pedestrian lights, so if you know when you go, you can figure out when's best to start revving. Unfortunately, it's a bit like MarioKart, if you start revving too early, you'll inevitably have to stop again before they'll change. Best to count a second or two before starting to move. I don't know whether the French or the Irish or any other red-green nation do this as well.
pjr10th wrote: ↑Mon Dec 19, 2022 13:34As people don't start to set off until the green light shows - unlike the UK where they are already off by the time the green shows - you could probably make the intergreen a second or so shorter and it'd still be safe.
I think this varies. In urban areas people tend to be a bit less patient. In the north I tend to find that people only set off on a green, whereas in London other drivers will expect you to be beginning to move at the point the green light illuminates.
It might have been Douglas Adams who wrote that the shortest measurable period of time known to science was defined as the interval between a London traffic light turning green and the car behind you beeping its horn.
Here in Russia, most junctions have no all-red period between 2 stages, so the green light turns on at the same time as the red light for the other road turns off.
Some bigger junctions do have an all-red period, but they're the exception rather than the norm.
Surprisingly, I've never seen any accidents caused by this. Maybe this is because the green light flashes for 3 seconds before changing to amber?
Pinzgauer wrote: ↑Fri Mar 11, 2016 16:22
Dumping my pendant's pen in the bucket - when did we cease using green lenses with "GO" on them? I remember "STOP" back painted on the red as a child, but amber and green were plain.
Me too.
I also wonder why the heads were black and white striped, looking at images from the '60s, yet the ones I remember were always black, yet the polls remained black and white?
The 'GO' lenses were certainly optional by the '50s (and likely earlier), and we're removed in the 1957 TSRGD. There was no saving time given for their removal (existing ones deemed to be compliant), but from what I've seen from photographs, very few were in use by then anyway.
The black and white striped lanterns were included in the '57 regulations, but fully black lanterns were prescribed in the 1964 (Worboys) regulations. I haven't been able to track down whether there was an amendment to the regulations that brought in the fully black lanterns earlier than '65, but it's possible.
An amendment in 1970 removed the requirement for 'STOP' on the red lens, and introduced 12" (300mm) green arrows and circular pedestrian aspects, which was to coincide with the introduction of the Mellor type traffic signals.
WhiteBlueRed wrote: ↑Tue Dec 20, 2022 08:52
Here in Russia, most junctions have no all-red period between 2 stages, so the green light turns on at the same time as the red light for the other road turns off.
Some bigger junctions do have an all-red period, but they're the exception rather than the norm.
Surprisingly, I've never seen any accidents caused by this. Maybe this is because the green light flashes for 3 seconds before changing to amber?
Most countries with that system then also have a hard prohibition to cross at amber. So the flashing green then basically functions like the amber, and amber operates as the all-red period. Which is how you avoid collisions despite not having an all-red period.
Going back to the 2005 paper, it’s nice that response time improves, but in the end this can be offset against the all-red period. Basically: if waiting amber means that the first in line crosses the stop line one second earlier than under a straight red-to-green, you could also have opted for straight red-to-green and an all-red phase that is one second shorter. Since that is the real question: not “who gets to the stop line faster”, but “what do you need to do intergreen to have a clear path without anyone having to wait unnecessarily.” Straight red-to-green then would save a few light bulbs and electricity, without compromising on that particular capacity point. Or am I missing something there?
Flashing green here is no different from steady green, it still means "go". The amber light means "you must stop if it's safe to do so".
EDIT: In Kazakhstan, flashing green does effectively act as the "amber" light. The rules prohibit going on an amber light if the traffic light is capable of displaying a flashing green light.
Last edited by WhiteBlueRed on Fri Feb 17, 2023 17:28, edited 2 times in total.
Regarding the word GO on the green lens, I’m of the belief it was dropped very early on although as a child in the late 50s early 60s I do remember seeing some, all on tin head types.
The last one I saw was at Finsbury Square, Moorgate in London around 1971/2. The paint had worn off but the impression in the lens was visible close up.
I’ve seen pictures of SGE types with GO on them mainly in the 30s/40s.
pjr10th wrote: ↑Mon Dec 19, 2022 13:34As people don't start to set off until the green light shows - unlike the UK where they are already off by the time the green shows - you could probably make the intergreen a second or so shorter and it'd still be safe.
I think this varies. In urban areas people tend to be a bit less patient. In the north I tend to find that people only set off on a green, whereas in London other drivers will expect you to be beginning to move at the point the green light illuminates.
It might have been Douglas Adams who wrote that the shortest measurable period of time known to science was defined as the interval between a London traffic light turning green and the car behind you beeping its horn.
Adams may have said the same, but Sir Terry definitely used the quote in Lords and Ladies.
“The shortest unit of time in the multiverse is the New York Second, defined as the period of time between the traffic lights turning green and the cab behind you honking.”
Did you know there's more to SABRE than just the Forums? Add your roads knowledge to the SABRE Wiki today!
Have you browsed SABRE Maps recently? Try getting involved!
Chris5156 wrote: ↑Mon Dec 19, 2022 21:32It might have been Douglas Adams who wrote that the shortest measurable period of time known to science was defined as the interval between a London traffic light turning green and the car behind you beeping its horn.
Adams may have said the same, but Sir Terry definitely used the quote in Lords and Ladies.
“The shortest unit of time in the multiverse is the New York Second, defined as the period of time between the traffic lights turning green and the cab behind you honking.”
That's almost certainly what I was thinking of! Thank you
