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

[deathtopumpkins]

Unrelated, and may have already been posted, but I discovered that NH 125 is full of FYAs in the center part of its route (mostly north of NH 101).

[myosh_tino]

What's the point of them?  They shouldn't be used in normal circumstances; left turning traffic shouldn't be forced to sit, twiddling their thumbs, even when it would be safe to make their turn just because someone decided to put in a dedicated left signal instead of a doghouse.  And if a flashing yellow signal is put in timed like a doghouse, it becomes pointless, as the existing rule (yield to oncoming traffic unless you have an arrow) is more than sufficient; the only difference is that it weeds out the people who are too stupid to drive safely.

The solution is not making it easier for dumb people to drive; it's to get them off the road entirely.

If you're referring to protected lefts, then I completely disagree.  In California protected lefts are the norm (some say we're the home of the protected lefts) and I find it far safer than permissive lefts because it eliminates the possibility of some yahoo turning left in front of you thinking "I think I can make this turn ... *crash* ... I shouldn't have made the turn".  While the driver making the left in the situation above could be considered "too stupid to drive safely", you have to take into account the safety of other motorists.

I have absolutely no problem waiting for a green arrow to make a left turn because in California, most signals are set up as "on demand" with sensor loops in the pavement.  In this mode, the wait time could be as little as 5 seconds.

[vdeane]

I have absolutely no problem waiting for a green arrow to make a left turn because in California, most signals are set up as "on demand" with sensor loops in the pavement.  In this mode, the wait time could be as little as 5 seconds.

Outside of NY 332, there are NO signals in NY that operate on-demand (that I know of) during the day.  Many stay on timers even in the middle of the night.

[myosh_tino]

I have absolutely no problem waiting for a green arrow to make a left turn because in California, most signals are set up as "on demand" with sensor loops in the pavement.  In this mode, the wait time could be as little as 5 seconds.

Outside of NY 332, there are NO signals in NY that operate on-demand (that I know of) during the day.  Many stay on timers even in the middle of the night.

Ah, that makes sense.  If signals are only on timers, then I can see the frustration with having to wait for a green arrow to make left turns.  Is there any reason (besides the cost of retrofitting signals) that on-demand is not more prevalent in other states like New York?

[Scott5114]

And if a flashing yellow signal is put in timed like a doghouse, it becomes pointless, as the existing rule (yield to oncoming traffic unless you have an arrow) is more than sufficient; the only difference is that it weeds out the people who are too stupid to drive safely.

A flashing yellow can be on next to a red ball.

In Moore, Oklahoma, a green ball can be on next to a red ball.

[SignBridge]

I believe New York State DOT has many more "actuated" and "semi-actuated" signals than Deanej realizes. At least on Long Island the major state roads have them. Gotta look carefully for those detector loops in the pavement to know they exist.

[US71]

FYA's are multiplying like rabbits here (Ft Smith). At least Five intersections with 5-signal Lefts have been replaced with FYA's just this Summer. The city is also replacing some existing signals with all-new poles and signals. I've yet to find anyone in the street department to say why some intersections need new poles.

[vdeane]

I believe New York State DOT has many more "actuated" and "semi-actuated" signals than Deanej realizes. At least on Long Island the major state roads have them. Gotta look carefully for those detector loops in the pavement to know they exist.

Just because they have them doesn't mean they always use them; most signals with the system (upstate at least) only use them at night.

[roadfro]

What's the point of them?  They shouldn't be used in normal circumstances; left turning traffic shouldn't be forced to sit, twiddling their thumbs, even when it would be safe to make their turn just because someone decided to put in a dedicated left signal instead of a doghouse.  And if a flashing yellow signal is put in timed like a doghouse, it becomes pointless, as the existing rule (yield to oncoming traffic unless you have an arrow) is more than sufficient; the only difference is that it weeds out the people who are too stupid to drive safely.

The solution is not making it easier for dumb people to drive; it's to get them off the road entirely.

An important distinction should be drawn between a "dedicated left" signal and the type of turn mode being used. A dedicated left signal is any signal head meant specifically to control the traffic in left turn lanes. This can be a protected display, a normal circular indication display (prior to 2009 MUTCD), a 5-section "doghouse" or similar (also prior to 2009 MUTCD), or an FYA--any of these mounted over the left turn lane (not on the lane line) is a dedicated left turn signal.

The FYA replacing a 5-section display isn't pointless. The all-arrow display of the FYA can work exactly the same as the 5-section head, but with the benefit of being an all-arrow display that isn't as easily misunderstood.

I agree that we shouldn't be letting less-competent drivers on the road should, but using a signal display that is more intuitive and less easily misunderstood helps all drivers, not just the dumb ones.

[roadfro]

Here is a situation where the flashing yellow arrow could be very helpful-but could it be used here?
This is Dallas Dr/Bell Av @ Eagle Dr in Denton Tx. The right 2 lanes are free-flow with no signals. The left turn movement used to be protected only, with two three-light heads w/ green arrows. It now has a protected and permissive phases. The issue here is that the permissive phase could be confused for protected since the signals control only the left-turn lane. I could see how this could confuse people even with the signs. However, I don't know if the flashing yellow arrow could be used here. The use of green balls w/green arrow is an issue since the thru movement is not signalized. This situation, while it sort of already exists, would be an issue since the flashing yellow arrow would need to be displayed wirth a green ball?
This is a very interesting situation to debate from an engineering perspective.

Current setup

An FYA could easily be used here. The flashing arrow is generally displayed with the opposing circular green, so there's no issue with that. The issue I see is the left turn lane being the only signalized approach, but the signal heads used don't really match up with a typical use in practice. I would mount one FYA signal above the left turn lane and use another FYA as a far left pole-mount. This removes the normal circular green from the equation and provides proper signal redundancy in case of indication failure in one display. The through lanes could have single-section green through arrows, but that's not entirely necessary.

[Central Avenue]

I never really understood the "we shouldn't accommodation stupid drivers" argument. I mean, there are stupid drivers out there, and there pretty much always will be, so if making things easier for them to understand makes them less likely to hit me I would consider that a good thing.

[vdeane]

If we revoked their licenses, they'd also be a lot less likely to hit you.

But I don't see what is unintuitive about a doghouse.  If there's an arrow, you have the ROW to turn, if there isn't, it behaves as if there was no specific left turn signal.  Simple.  A flashing yellow is actually less intuitive because you have to know what the flashing yellow means.  You don't need to know anything to understand a doghouse, especially in states that only use two through signals + 1 turn signal (in the rare event of a fully protected left) regardless of the number of travel lanes.

[74/171FAN]

These have started appearing throughout Blacksburg now instead of just the Virginia Tech Campus.

[Central Avenue]

If we revoked their licenses, they'd also be a lot less likely to hit you.

But how do you know whose license to revoke? I'd rather not wait until they do cause an accident to declare them unfit to drive...

(Also that assumes that people without licenses won't drive, which isn't necessarily true.)

[roadfro]

But I don't see what is unintuitive about a doghouse.  If there's an arrow, you have the ROW to turn, if there isn't, it behaves as if there was no specific left turn signal.  Simple.  A flashing yellow is actually less intuitive because you have to know what the flashing yellow means.  You don't need to know anything to understand a doghouse, especially in states that only use two through signals + 1 turn signal (in the rare event of a fully protected left) regardless of the number of travel lanes.

People do not always fully understand that a circular green by itself indicates that left turning traffic must yield to oncoming traffic and pedestrians legally within the intersection--it's a "green means go" mentality that is not always the correct interpretation. This happens despite the typical presence of the "LEFT TURN YIELD ON [GREEN BALL]" sign.

There is also the fact that a 5-section display commonly shows both a circular red and a green arrow, when allowing leading protected left turns. Seeing red and green in the same signal face simultaneously sends mixed messages to drivers, and some do not know the proper course of action. A driver *does* need to know how to interpret this display, depending on their intended direction of travel--the number of signal heads or travel lanes doesn't really have anything to do with it.

With the FYA display being only arrows, it is unmistakeable to drivers that the arrow applies to turning traffic versus the 5-section heads that contain arrows and balls. Having a display dedicated to the turning traffic reduces confusion. The flashing yellow itself signifies a caution situation and reinforces the need to proceed carefully.

[NE2]

There is also the fact that a 5-section display commonly shows both a circular red and a green arrow, when allowing leading protected left turns. Seeing red and green in the same signal face simultaneously sends mixed messages to drivers, and some do not know the proper course of action. A driver *does* need to know how to interpret this display, depending on their intended direction of travel--the number of signal heads or travel lanes doesn't really have anything to do with it.

In addition, a doghouse cannot show a red ball and a permissive left turn. The "solution" (use a separate doghouse over the left turn lane) is confusing at best, since would have to show a green ball when straight traffic has a red.

[DTComposer]

If you're referring to protected lefts, then I completely disagree.  In California protected lefts are the norm (some say we're the home of the protected lefts)

Depends what part of California. In much of Los Angeles (including Hollywood, much of the San Fernando Valley, San Pedro) protected lefts are definitely not the norm as opposed to Orange County. Same for San Francisco. However, I know they're much more prevalent in San Jose.

Saw my first FYA in Fullerton, at Euclid and Malvern. Got a good look at it, as the driver in front of me wasn't sure how to respond, sat for 6 or 7 seconds, lurched forward, stopped again, then finally went (this was with no opposing traffic coming towards us).

[vdeane]

If drivers think a green ball means "I can do whatever I want even if I'm making a left turn and the other direction has a green ball", then the area probably has far too many protected lefts.  Fully protected lefts should be outlawed except if an engineering study proves that there is too much traffic for the typical permissive left or doghouse type left.

If having the green arrow with a red ball is too confusing, you could just change the signal to have each direction go at a different time.  There are many signals in NY where one direction of traffic will have a leading green so that turning traffic in that direction can get an arrow.

If we revoked their licenses, they'd also be a lot less likely to hit you.

But how do you know whose license to revoke? I'd rather not wait until they do cause an accident to declare them unfit to drive...

(Also that assumes that people without licenses won't drive, which isn't necessarily true.)

More rigorous testing to get a licence in the first place.  The road tests we do in the states are a joke; the standards should be as high as in Germany.

There is also the fact that a 5-section display commonly shows both a circular red and a green arrow, when allowing leading protected left turns. Seeing red and green in the same signal face simultaneously sends mixed messages to drivers, and some do not know the proper course of action. A driver *does* need to know how to interpret this display, depending on their intended direction of travel--the number of signal heads or travel lanes doesn't really have anything to do with it.

In addition, a doghouse cannot show a red ball and a permissive left turn. The "solution" (use a separate doghouse over the left turn lane) is confusing at best, since would have to show a green ball when straight traffic has a red.

Why would such a phase exist in the first place?

[agentsteel53]

In addition, a doghouse cannot show a red ball and a permissive left turn. The "solution" (use a separate doghouse over the left turn lane) is confusing at best, since would have to show a green ball when straight traffic has a red.

Why would such a phase exist in the first place?

couldn't there be a red ball and a flashing yellow left arrow in the same doghouse?  or am I misinterpreting what the flashing yellow arrow means?

the reason for it is to increase traffic capacity in particular situations - namely, when one particular left turn is heavy (say, southbound to eastbound) but southbound straight traffic is light, as is northbound to westbound.  it doesn't make sense to either put the northbound to westbound left on a protected turn, or to entirely stop southbound straight traffic.  both are light enough, and visibility is good enough, that they can maneuver safely.

I run across that situation a lot and wish for the permissive left, which I could make very safely.  around here, the left turn I wish to make gets a red arrow and I have to wait, even though hardly any cars come straight to oppose me.

[corco]

Best solution I've see is to do as Tucson does it and make all left turns permissive unless otherwise posted (very rare- only a few low-visibility, high traffic intersections prohibit this), and then have the protected phase lag. It could still work with leading lefts too- just post a green ball over the left hand turn lane that transitions to a green arrow when the turn is protected. No need for a doghouse or a FYA.

[NE2]

In addition, a doghouse cannot show a red ball and a permissive left turn. The "solution" (use a separate doghouse over the left turn lane) is confusing at best, since would have to show a green ball when straight traffic has a red.

Why would such a phase exist in the first place?

Not the best example, but let http://www.bouldercolorado.gov/flash/departments/Transportation/yel_solution.swf run through until northbound gets a red.

[kphoger]

In addition, a doghouse cannot show a red ball and a permissive left turn. The "solution" (use a separate doghouse over the left turn lane) is confusing at best, since would have to show a green ball when straight traffic has a red.

Why would such a phase exist in the first place?

couldn't there be a red ball and a flashing yellow left arrow in the same doghouse?  or am I misinterpreting what the flashing yellow arrow means?

Or use a red straight-ahead arrow along with a flashing yellow left arrow, thereby clearly defining each movement.

[mukade]

So I missed something simple. Why is the solid green ball bad and the flashing yellow arrow good? Were there a spate of accidents caused by people misinterpreting a green light or something? People are suggesting a ton of ideas that all have the same effect of a solid green ball that drivers are very familiar with. Unless there are reliable, objective studies stating otherwise, I think changing something as fundamental as a traffic light is both dangerous and a waste of money.

[agentsteel53]

Or use a red straight-ahead arrow along with a flashing yellow left arrow, thereby clearly defining each movement.

now that sounds like one hell of a retrofit.  straight-ahead arrows are pretty uncommon in the US, especially red ones.

[kphoger]

Or use a red straight-ahead arrow along with a flashing yellow left arrow, thereby clearly defining each movement.

now that sounds like one hell of a retrofit.  straight-ahead arrows are pretty uncommon in the US, especially red ones.

Agreed.  But I guess agree with the post above yours.  The FYA is unnecessary.  If there's a location that just absolutely needs it, then just splurge on a red straight-ahead arrow assembly.