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

[Brandon]

Probably because tests have shown the doghouse-style *ISN'T* sufficient, especially with older drivers.  If it was sufficient, the FYA wouldn't have come about to begin with.

I always assumed FYA was to replace the flashing red ball and other divergent left turn signals (non-standard) in place in many states.  The tower or doghouse (depending on state) is not affected from what I can see as that has separate green and yellow arrows for a protected left and already provides for a permitted left.

[Revive 755]

Probably because tests have shown the doghouse-style *ISN'T* sufficient, especially with older drivers.

And it's probably those same older drivers who sit at a green light and don't move until the light turns yellow (going straight across the intersection, not turning), or go 35 mph on the interstate that has a minimum speed of 40 mph.

[Tarkus]

Oregon has at least one intersection with them -- NE Sandy Blvd at NE 28th Ave in Portland.

Oregon should have a lot of FYA's. They were one of the first states to do widespread implementation under the FHWA's experimentation process and subsequent interim approval of FYA.

I found this on ODOT's site awhile ago . . . a list of all FYAs in Oregon, as of 11/30/2009, showing the dates of installation.  Counted 187 of them.  There's actually been at least a couple more since then, as the ones at the OR-569 interchange with Coburg Road in Eugene.  The first one was apparently installed at Table Rock Road and Vilas Road in Jackson County in May 2001.

Also, ODOT has mandated using FYAs on all state highway installations as per the most recent Traffic Signal Policy and Guidelines document and generally discouraged their usage elsewhere.

-Alex (Tarkus)

[froggie]

I always assumed FYA was to replace the flashing red ball and other divergent left turn signals (non-standard) in place in many states.  The tower or doghouse (depending on state) is not affected from what I can see as that has separate green and yellow arrows for a protected left and already provides for a permitted left.

Replacing the flashing red ball (or in Delaware and Maryland the flashing red arrow) is an ancillary effect.  But the primary reason for the FYA's development and purpose is because too many drivers were confusing the steady green (i.e. the permitted left) on the tower or the doghouse signals for a protected left.

[SignBridge]

Guys, you really need to read the new MUTCD standards carefully on this subject. They have made it very complicated, but let me give you the short version. The problem they are addressing is that some drivers when viewing a green ball directly above the left-turn lane, would think that it was a right-of-way signal for that lane, the same as a green arrow. So they've mandated that a separate left-turn signal directly above the L/T lane can't have a green-ball anymore; it must display a steady green-arrow or flashing yellow-arrow, if it's directly above the L/T lane. However, as I cited in my previous post, if a supplemental left-turn head is not used over that lane, then a doghouse may still be used directly above the lane-line separating the left-turn and left-thru lanes.
I myself, had to read the Manual several times to understand the new rules. Also, the new standard only applies to new and rebuilt installations. There is no requirement to change existing signals. So watch what they do in your locale when installing new signals or rebuilding old ones.

[Brandon]

I always assumed FYA was to replace the flashing red ball and other divergent left turn signals (non-standard) in place in many states.  The tower or doghouse (depending on state) is not affected from what I can see as that has separate green and yellow arrows for a protected left and already provides for a permitted left.

Replacing the flashing red ball (or in Delaware and Maryland the flashing red arrow) is an ancillary effect.  But the primary reason for the FYA's development and purpose is because too many drivers were confusing the steady green (i.e. the permitted left) on the tower or the doghouse signals for a protected left.

That is stupid.  The towers work just fine and don't seem to have the same problems, IMHO.  A green ball is already well known while taking any sort of drivers ed that it is for the permissive phase of all turns and straight, not the protected phase.  The fools who think a green ball is protected aren't going to suddenly think a flashing yellow arrow means anything different.

[froggie]

FHWA thinks otherwise...

[vdeane]

This is why other states should follow NY's lead and not use separate signals for left turn lanes unless absolutely necessary.  Most of the time there's no reason for one.  If all the lanes have the same signal except for arrows, it's a lot less confusing.

[Brandon]

Froggie, it says that "some engineers have had concerns that drivers turning left on a permissive circular green signal indication might inadvertently mistake that indication as implying the left turn has the right of way".  This means that some, not all, not many, but some think people get this mixed up.  I sincerely doubt many drivers mistake a green ball for a green arrow in states where green arrows are typically used with green balls for protected and permissive stages.  I would guess that the mistakes are mostly made by people who come from states with separate signal housings into states with tower or doghouse assemblies.  This is a drivers ed issue, not an engineering one IMHO.  If people are too stupid to understand the difference between a green ball and a green arrow, then they won't understand a FYA either as that will require education in states that use tower or doghouse assemblies.  We've used tower assemblies here in Illinois since the 1960s (from the signals I've seen) with great success.  I sincerely doubt IDOT (much less the municipalities) will change and start using the FYA.  They don't even use doghouse assemblies here (which I can see getting mixed up easier as the green ball and green arrow are next to each other).

Deanej, I agree.  In addition, I would suggest more use of permissive phase left turns and getting rid of protected phase only left turn signals.

[Brandon]

Reading through the actual study, it appears to be somewhat flawed.
http://wwwcf.fhwa.dot.gov/exit.cfm?link=http://trb.org/publications/nchrp/nchrp_rpt_493.pdf

The study areas were in Washington, Oregon, Michigan, Texas (2), California, Florida, and Delaware.  Of these, they break down the signal types as follows:

Michigan: 3 display signal, spearate left turn signal (flashing red ball).
Washington: 4 display signal, spearate left turn signal (flashing yellow ball).
Oregon and Florida: doghouse cluster of signals.
California: 3 signal display, separate left turn signal (flashing red arrow).
Delaware: 4 signal display, separate left turn signal (flashing red arrow).
Texas: 5 signal display horizontal.  One cluster was studied (see FL & OR) and only one tower was studied in a state that typically uses the horizontal arrangement.

In none of these was a tower studied in a state that typically uses towers (such as Illinois).  And other comprehension techniques were never looked at from what I can see.  Downstate, a lot of signals have a supplimentary sign stating "Left Turn Yield on {green ball}".  That seems to have never been looked at.

Judging from the implementation sites listed later, it seems as though the doghouse cluster of signals provides the most confusion and hesitation as to the meaning of the signals.  The tower signal in Tuscon, AZ had no hesitation nor confusion, but the doghouses in other areas did.  Looking at this data, I'd say that the doghouse style of signals has a big flaw, not the protected/permissive phasing of the ball and arrow.  I can see how confusion would happen when the ball and the arrow are directly next to each other.

There also seems to be a problem with the yellow trap created when opposing signals are phased differently.  The solution, IMHO, would be to eliminate the phasing creating it.  When opposing traffic has a green (while the subject traffic has a red) the left turns should not be permitted.

Personally, from the study, I would also suggest eliminating the doghouse signal from the MUTCD and using the tower exlusively.

[US71]

... it says that "some engineers have had concerns that drivers turning left on a permissive circular green signal indication might inadvertently mistake that indication as implying the left turn has the right of way".  This means that some, not all, not many, but some think people get this mixed up.

Does this look confusing to you?

[froggie]

Confusing and very much in error.

[Scott5114]

Not an error. That's "Dallas Phasing", which we have discussed before on this board.

[Brandon]

Not an error. That's "Dallas Phasing", which we have discussed before on this board.

To me, Dallas Phasing looks strange.  We don't use it here in Illinois.  Here, the ball would be red.

[SignBridge]

I'm not familiar with "Dallas Phasing" but I would be confused by that display in the picture. I had to look at it closely to confirm the left-turn signal was displaying a green-ball while the "thru" signals were red. I could easily see the mistake being made here that FHWA is talking about.  Under what circumstances would a green ball be appropriate for left turn but not thru lanes?

But even besides that example, in some cases the issue exists when just a 3rd standard R-Y-G ball head is used over the left-turn lane in addition to the usual 2 required heads. Brandon is correct that all drivers should know that you have to yield on a green-ball, but apparently there is confusion among some drivers when the signal-head is directly above the L/T lane. I don't understand it either, bit I think FHWA is right to try to address the issue in a way that works for the ignorant public to reduce accidents.

[realjd]

I'm not familiar with "Dallas Phasing" but I would be confused by that display in the picture. I had to look at it closely to confirm the left-turn signal was displaying a green-ball while the "thru" signals were red. I could easily see the mistake being made here that FHWA is talking about.  Under what circumstances would a green ball be appropriate for left turn but not thru lanes?

They show an unprotected left with red through lanes when opposing traffic has a protected left and green through lanes. This phasing was designed to eliminate the yellow-trap. I'm not sure about the setup in this picture, but in Dallas, the green signal is shielded so only the turn lane can see it.

[US71]

They show an unprotected left with red through lanes when opposing traffic has a protected left and green through lanes. This phasing was designed to eliminate the yellow-trap. I'm not sure about the setup in this picture, but in Dallas, the green signal is shielded so only the turn lane can see it.

The green is NOT shaded here (or wasn't when the photo was taken). It may simply be inattentiveness, but the blue Honda hit the white car a couple seconds later and drove away.

[agentsteel53]

yellow-trap.

what is this?

[froggie]

This.

[Brandon]

This.

IMHO, it should be completely prohibited, and the whole signal issue just fades away.  Minimal cost and effort.

[agentsteel53]

heh.  Whenever I see the light turn yellow, I assume the cars in the opposite direction also get yellow, and therefore are liable to floor it to beat the red.  

The only time I assume cars are slowing down is when I visibly see them slow down.  This gives me enough time to enter the intersection on yellow, and then I exit the intersection on red (which is perfectly legal - and just about the only possible way to make a left turn in Los Angeles, and various other places).

[realjd]

It depends on where you are. In Indiana (and other midwestern states), often several cars will enter while the light is green and turn when it turns yellow, but people almost always stop on yellow there. I learned quickly to break that habit when I moved to Florida since so many people run late yellow/early red lights. I'll sit at the line and wait for the protected left next cycle if I have to.

Of course, now whenever I visit family back in Indiana, I'll sometimes get honked at for not moving into the intersection!

[agentsteel53]

It depends on where you are. In Indiana (and other midwestern states), often several cars will enter while the light is green and turn when it turns yellow, but people almost always stop on yellow there. I learned quickly to break that habit when I moved to Florida since so many people run late yellow/early red lights. I'll sit at the line and wait for the protected left next cycle if I have to.

Of course, now whenever I visit family back in Indiana, I'll sometimes get honked at for not moving into the intersection!

yes, in the case of there being a wide median, I can move into it on the green, while still allowing opposing traffic to pass through the intersection at full speed.  However, on a typical LA city street, there is not enough room to do that - I can barely creep into the intersection, just enough to display my intent, but to actually start to make the turn would cut off the innermost lane of opposing traffic.

[Phudman]

They have been popping up in Tyler, TX for the past year.

[andytom]

They're all over Beaverton.  After 4 or 5 years of waiting, they finally put one at the intersection where I turn into my apartment community a couple of weeks ago.  It greatly reduces the time I have to sit at that signal to turn left.  They were using a 4 lamp signal for a while but are currently using a 3 lamp signal with the steady green and the flashing yellow arrows in the bottom position.

There shouldn't be a reason to reduce to a three-section display unless physical conditions require it.
[/quote]

With every level of government below federal scrimping for money anywhere they can find it?  Sounds like a good enough reason.

--Andy