Has the flashing yellow left turn signal made it to your state?

[Revive 755]

Is it my bad memory, or did a lot of people on here dislike the introduction of the FYA nine years ago or whenever that was?  I don't hear anybody complain about them anymore, though.

I've changed my mind on them since their introduction.  I think it's partially due to having one too many times of getting to a signal too late to trigger the green left turn arrow and having to wait a whole cycle, whereas I would have been able to make the turn had a FYA been present due to only being opposed by left turning vehicles and/or one or two through vehicles.

[thenetwork]

I've never had a problem with them.  I've always likened them to and grew up with the flashing red balls on Michigan traffic lights.

[mrsman]

Is it my bad memory, or did a lot of people on here dislike the introduction of the FYA nine years ago or whenever that was?  I don't hear anybody complain about them anymore, though.

I've changed my mind on them since their introduction.  I think it's partially due to having one too many times of getting to a signal too late to trigger the green left turn arrow and having to wait a whole cycle, whereas I would have been able to make the turn had a FYA been present due to only being opposed by left turning vehicles and/or one or two through vehicles.

I think a lot of the concern had to do with how other drivers would interpret the signal.  Would they interpret it as a right of way (like flashing yellow ball in many night-time flash signals)?  Would there be concerns of a perceived yellow trap (Drivers focusing their attention on the thru lights to presume that opposing traffic gets yellow ball at the same time as concurrent traffic)?  Over the test of time, these fears have been shown to be irrational and people have caught on to their true meaning.

It's just a matter of time before we make all the lefts FYAs.

[SignBridge]

Time for an update as this thread has been inactive for a while. After a very slow start New York DOT's Region 10 on Long Island is now installing flashing-yellow arrows in a frenzy of new activity.

Two new signals at previously unsignaled intersections on N.Y. 106 (Newbridge Rd.) in Hicksville have them on both the state road AND coming out of the side street.

Also a rebuild of an existing signal at Newbridge Rd. and Duffy Ave. just south of the Hicksville train station. *******And in a surprising development that signal now includes so called Dallas Phasing using the FYA in place of the traditional green-ball, the first time I've ever seen that phasing in actual practice. What a surprise when I saw that FYA operating, simultaneously with red-balls showing over the thru lanes.

[jakeroot]

And in a surprising development that signal now includes so called Dallas Phasing using the FYA in place of the traditional green-ball, the first time I've ever seen that phasing in actual practice. What a surprise when I saw that FYA operating, simultaneously with red-balls showing over the thru lanes.

You can still have the FYA active with a red through signal when the oncoming left has a green arrow. Or I'm guessing the FYA was active alongside a green through signal, before the through signal changed to red?

It is interesting how some parts of the country seem to have very little imagination. I've been seeing lead/lag FYA for years now. At least for as long as I've been driving.

[Amtrakprod]

And in a surprising development that signal now includes so called Dallas Phasing using the FYA in place of the traditional green-ball, the first time I've ever seen that phasing in actual practice. What a surprise when I saw that FYA operating, simultaneously with red-balls showing over the thru lanes.

You can still have the FYA active with a red through signal when the oncoming left has a green arrow. Or I'm guessing the FYA was active alongside a green through signal, before the through signal changed to red?

It is interesting how some parts of the country seem to have very little imagination. I've been seeing lead/lag FYA for years now. At least for as long as I've been driving.

I would agree, I cannot name any Massachusetts Flashing Yellow Arrow intersection that uses lead-lag, I know they're 350 but I know at least 300. In fact the only signals I know that has lead-lag in MA are: https://www.google.com/maps/@42.3973532,-71.1300862,3a,27.4y,319.82h,92.59t/data=!3m6!1e1!3m4!1sqbLXFRINhdQdeOe7O09Vog!2e0!7i13312!8i6656
and https://www.google.com/maps/@42.4155253,-71.1533173,3a,75y,114.84h,91.66t/data=!3m6!1e1!3m4!1sDJVpcWRG-JnjlgaTPTCKww!2e0!7i13312!8i6656

[SignBridge]

Jakeroot, I think you just described Dallas Phasing.  The northbound signals went from thru green with FYA to thru-red with steady-red arrow (while cross traffic had the green) to thru-red with FYA while southbound had thru-green with green left-turn arrow.

[jakeroot]

Jakeroot, I think you just described Dallas Phasing.  The northbound signals went from thru green with FYA to thru-red with steady-red arrow (while cross traffic had the green) to thru-red with FYA while southbound had thru-green with green left-turn arrow.

Dallas Phasing wasn't really a phasing at all. It was just an operation style that allowed 5-section signals to operate independently of through signals, for the purpose of implementing lead/lag phasing with permissive lefts. Ostensibly, Dallas Phasing only exists to permit lead/lag operation, but Dallas Phasing, in and of itself, isn't lead/lag phasing.

What I was trying to describe was a situation where no one was in the left turn lane going one direction, but the opposite left turn lane was occupied. At the start of the phase, the oncoming direction would have both a green through and left turn signal, whereas the other direction would have a red through signal, but an FYA for the left turn since it can run independently. It looks like a lead/lag situation, but it was actually just a lead/lead signal without any cars to activate the green arrow, hence why it went straight to FYA while simultaneously holding through traffic during the oncoming protected left. I think there are places in the US that don't allow this, but I haven't driven anywhere that has. Certainly no such restrictions out west or in VA or DC.

[Amtrakprod]

Jakeroot, I think you just described Dallas Phasing.  The northbound signals went from thru green with FYA to thru-red with steady-red arrow (while cross traffic had the green) to thru-red with FYA while southbound had thru-green with green left-turn arrow.

Dallas Phasing wasn't really a phasing at all. It was just an operation style that allowed 5-section signals to operate independently of through signals, for the purpose of implementing lead/lag phasing with permissive lefts. Ostensibly, Dallas Phasing only exists to permit lead/lag operation, but Dallas Phasing, in and of itself, isn't lead/lag phasing.

What I was trying to describe was a situation where no one was in the left turn lane going one direction, but the opposite left turn lane was occupied. At the start of the phase, the oncoming direction would have both a green through and left turn signal, whereas the other direction would have a red through signal, but an FYA for the left turn since it can run independently. It looks like a lead/lag situation, but it was actually just a lead/lead signal without any cars to activate the green arrow, hence why it went straight to FYA while simultaneously holding through traffic during the oncoming protected left. I think there are places in the US that don't allow this, but I haven't driven anywhere that has. Certainly no such restrictions out west or in VA or DC.

Yes, Dallas Phasing is the use of louvers over the green (and yellow) sections on a doghouse so the doghouse can remain green while the opposing direction has the left arrow to remove the yellow trap. The whole difference in whole can be very understandably  explained here:

The FYA use of the flashing yellow arrow while the red ball is just to prevent yellow trap, it's not Dallas phasing though, even though it performs the same task.

[roadfro]

^ Glad to see my PPLT explanatory video from nine years ago (*gasp!*) is still referenced online

[jakeroot]

^ Glad to see my PPLT explanatory video from nine years ago (*gasp!*) is still referenced online

It's a very well-made video! Damn near 90k views. Funny that it's mostly irrelevant now, though, since most Dallas-phased signals have been removed.

[GaryV]

I saw something interesting last week - a FYA that didn't flash.

As I reached the intersection the light was red for my direction (thru and left turn).  An ambulance came through on the cross street.  When the light changed, the thru was green (even though that intersection has a leading protected left turn).  The left turn signal, a four-head, had a solid left turn arrow in the second from bottom position - the position that normally would flash.

I wonder if the ambulance had some kind of activation that would keep the cross street signal green for it, and when the controller took over from the special activation it malfunctioned slightly. 

I didn't stick around to see if the signal went to back to normal on the next cycle.  But it's been ok on other days I went that way.

[jakeroot]

I saw something interesting last week - a FYA that didn't flash.

Pretty much guaranteed that something went wrong. Was it displaying a solid yellow arrow?

I have seen a solid yellow arrow in the same lens as a flashing yellow arrow, but only as part of a three-section FYA, not four-section.

I do find it odd that the signal changed to green for your direction when an ambulance approached from a side-street. You'd think any sort of preemption system would keep their light green.

[texaskdog]

How does waiting in the intersection for a gap in oncoming traffic to make a turn create gridlock?  You're guaranteed to get a gap eventually - when the light goes red.  If you don't wait, however, you might never get to go if there is no protected phase.  Going into the intersection when the place you're headed to is blocked ("blocking the box"), on the other hand, is a big issue.

sometimes there is never a break

[jakeroot]

How does waiting in the intersection for a gap in oncoming traffic to make a turn create gridlock?  You're guaranteed to get a gap eventually - when the light goes red.  If you don't wait, however, you might never get to go if there is no protected phase.  Going into the intersection when the place you're headed to is blocked ("blocking the box"), on the other hand, is a big issue.

sometimes there is never a break

Note the bolded part.

[Amtrakprod]

I saw something interesting last week - a FYA that didn't flash.

As I reached the intersection the light was red for my direction (thru and left turn).  An ambulance came through on the cross street.  When the light changed, the thru was green (even though that intersection has a leading protected left turn).  The left turn signal, a four-head, had a solid left turn arrow in the second from bottom position - the position that normally would flash.

I wonder if the ambulance had some kind of activation that would keep the cross street signal green for it, and when the controller took over from the special activation it malfunctioned slightly. 

I didn't stick around to see if the signal went to back to normal on the next cycle.  But it's been ok on other days I went that way.

Was this during rush hour? Many cities make the signal protective during rush hour.

[SignBridge]

Emergency vehicles equipped with transmitters for traffic signal pre-emption is nothing new. I have seen them operate in some places and it does screw up the normal sequence of the signals in some cases. Although they must be helpful to emergency vehicles, they can cause havoc with the signal phasing and traffic flow after the vehicle passes thru. I've seen it create a confusing picture to approaching drivers, including myself.

[UCFKnights]

Although they must be helpful to emergency vehicles

I question that. The ones near me seem to detect the vehicles too late to be useful. By the time the light actually pre-empts, the emergency vehicle is typically in the intersection already and it only seems to serve to delay traffic. I think the city figured it out, as I've noticed they've stopped installing them on new lights for the past couple years, and I think they actually turned them off on the old ones fairly recently, and they're supposedly working on a new solution (they currently use the strobe detectors).

[GaryV]

I saw something interesting last week - a FYA that didn't flash.

Pretty much guaranteed that something went wrong. Was it displaying a solid yellow arrow?

I have seen a solid yellow arrow in the same lens as a flashing yellow arrow, but only as part of a three-section FYA, not four-section.

I do find it odd that the signal changed to green for your direction when an ambulance approached from a side-street. You'd think any sort of preemption system would keep their light green.

Correct, the 2nd from the bottom position showed a solid yellow arrow instead of flashing.
The light turned green for me after the ambulance had cleared.

Yes it was rush hour, but this intersection has FYA, with a leading protected green.  The leading green didn't happen, and then the FYA didn't flash.

[jakeroot]

Yes it was rush hour, but this intersection has FYA, with a leading protected green.  The leading green didn't happen, and then the FYA didn't flash.

I see. Sounds like a programming error. You may want to contact the local public works agency to let them know what you saw, so they can check their end.

[Amtrakprod]

Yes it was rush hour, but this intersection has FYA, with a leading protected green.  The leading green didn't happen, and then the FYA didn't flash.

I see. Sounds like a programming error. You may want to contact the local public works agency to let them know what you saw, so they can check their end.

Jake, I saw my first (and second) lead-lag FYAs yesterday! I thought they were very nice: https://www.google.com/maps/@42.6748061,-71.1279975,3a,30y,307.43h,92.81t/data=!3m6!1e1!3m4!1sNoDc9nP6yydujvmd5DzJFA!2e0!7i13312!8i6656
and https://www.google.com/maps/@42.6731414,-71.125743,3a,75y,309.2h,77.35t/data=!3m6!1e1!3m4!1skITWxE9NWJ5zZzyRNBRLGg!2e0!7i13312!8i6656

[US71]

I just got back from a few days around Natchitoches, Louisiana, and I didn't see any.  171 around Shreveport has a lot of doghouse signals, but no FYA's.

[fwydriver405]

There are two new FYA's in Portland, Maine - one at the intersection of Commercial St and the Casco Bay Bridge entrance, and another one on Forest Avenue at Baxter Blvd and Bedford St. More FYA's in Maine are slated to start appearing later this year, particularly in Sanford and Springvale later this year as part of a USDOT Build Grant project to replace Maine's aging traffic signal infrastructure.

The Commercial St example below still has a doghouse on the opposing direction, which still causes yellow trap on the doghouse side if the FYA is under phase skip. However, the leading left turn is only called or recycled if there is a line of cars (usually 5 or 6) on the FYA side and there are no cars on the side street.


The Forest Street example utilises a single lead which replaced a protected-only signal that was in place.


Also, do other states have restrictions on where FYA's can be placed? I recently heard that MaineDOT policy mandates 24/7 protected only operation if a single-lane left turn crosses two or more opposing thru lanes, which means that any permissive movements are only allowed if the left turn crosses one opposing thru lane. I also noticed that although FYA's have started to appear in Maine, New Hampshire and Massachusetts, FYA's in NH and MA do not show the red arrow after the leading left turn expires, while in ME after the leading left turn, a red arrow is shown for a few seconds then FYA when the opposing movement is released.

[tradephoric]

Is it my bad memory, or did a lot of people on here dislike the introduction of the FYA nine years ago or whenever that was?  I don't hear anybody complain about them anymore, though.

My concern with the FYA has been in regards to safety.  When it was introduced in SE Michigan, there was roughly a 30% increase in injury accidents at FYA installs (and a 75% increase in head-on left-turn accidents which can be directly attributed to the left-turn signal phase operation).



IMO, the FYA isn't inherently dangerous, but the added flexibility the FYA provides can add confusion to drivers.  If the signal operation is like-for-like after the FYA install i wouldn't expect much change in the crash rate, but that's often not the case.  Even though the FYA solves the "yellow trap" problem, "perceived yellow traps" should be avoided whenever possible.

[paulthemapguy]

Just make every permissive turn a leading turn and not a lagging turn, like Illinois does ¯\_(ツ)_/¯