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

[roadfro]

Just saw a right-turn FYA for the first time in Oregon on Monday <...> It's also opposite a standard left-turn FYA, and the two signals' flashing is out of sync.

I make the assumption that the flashing out of sync is more due to the phase activation in the cycle. I.e. the controller does flashes at a set rate (say 60 flashes/minute) and the flash starts at the moment the phase activates, so if the left arrow starts at 0 seconds and the right arrow starts at 1.5 seconds into the cycle, they are going to be half a second out of sync.

I've noticed differences in flashing between FYAs and flashing hands of pedestrian signals, which I suspect operate similarly.

[txstateends]

The first flashing yellow left arrow has been installed in Amarillo, as of late last month:
http://www.newschannel10.com/story/25095399/new-turning-arrow-to-help-traffic-flow-at-intersection-in-amarillo

[talllguy]

TLDR the entire thread, but 2011 MD MUTCD Section 4D.04 03E2: Flashing yellow arrow indications shall not be used in Maryland.

That pretty much settles that.

[Revive 755]

I took a look at the one in Nebraska on SB NE 31 at the EB I-80 ramps.  The four-section head is mounted horizontally, and uses the text version of the 'left turn yield on flashing yellow arrow' sign.

North Liberty, Iowa, appears to have recently installed a few more on Penn Street between I-380 and former IA 965.

[andy3175]

Saw the FYA in Idaho and Wyoming during my Yellowstone trip.  I really like the concept and wish PennDOT would adopt to replace all the doghouse signals in Philly.

I'm not sure if this had been mentioned already ... A recent reconstruction (ca. 2008-2009) of Wyoming 59 through Gillette resulted in the installation of several FYA's along Douglas Highway from I-90 south past several signalized intersections for about a mile through the commercial strip (past a Wal Mart, K Mart, and a variety of other chain stores).

Regards,
Andy

[KEK Inc.]

Just saw a right-turn FYA for the first time in Oregon on Monday--it is (*surprise, surprise*) in Washington County, at the intersection of NW Cornell Road and NW Evergreen Pkwy/179th Ave.  The right-turn FYA is a three-lens (as are most of the installations in The WC now) on the westbound Cornell approach, and replaced a McCain Fresnel that had been there since the signal was installed in 1995.  It's also opposite a standard left-turn FYA, and the two signals' flashing is out of sync.  The county had been installing a bunch of straight five-lens right-turn signals in the past year--this one might be an experiment, though as crazy as they are about the FYA (we have several hundred of them, and they're at probably 85% of all signalized intersections here now), I suspect there will be more.

I know Beaverton has had them on OR-8 since 2007.

[Revive 755]

It appears Kane County, IL, is hoping to install more FYA's on Randall Road around 2016, per this document (assuming they ever get around to getting the first batch installed on Randall Road).

[route56]

There's been a change at the first FYA installation in Lawrence.

When the intersection of 19th and Louisiana was re-done, they installed left turn lanes in each direction, with East-West traffic on 19th having a protected-only signal (with a circular red) and North-South traffic on Louisiana having a protected/permitted signal using the FYA design. Recently, the Protected-only signals were converted to protected/permitted -- so now, the intersection has FYA signals in all four directions.

[Eth]

GDOT has installed two FYAs in Forsyth County north of Atlanta in the past month and "FYA will now be Georgia DOT's preferred left turn traffic signal for eligible locations — those with high numbers of left-turn movements and resultant traffic back-ups and related accidents." http://www.dot.ga.gov/informationcenter/pressroom/PressReleases/SR9-3-6-14.pdf

On that note, I found one tonight on SR 124 at Pharrs Rd in Snellville. First one I've seen in the state.

TLDR the entire thread, but 2011 MD MUTCD Section 4D.04 03E2: Flashing yellow arrow indications shall not be used in Maryland.

That pretty much settles that.

Interesting. So does that mean the existing ones in Montgomery County have been/will be removed? I know there was at least one in place around 2010-11, I want to say on MD 117, at or near the intersection with either MD 118 or 119.

[txstateends]

This new mast-arm signal just north of downtown Dallas (which replaced a tacky span-wire) is one of the first signals to use a blinking yellow left arrow in Dallas.  Since it is new to most around town, I would think at least a temporary helpful sign next to that part of the signal would be there to alert them, as other cities and areas have done.  Nope.  Just the signal.  Maybe the unfamiliar have to guess, or they've possibly seen media or online reports about the yellow arrow.  Either way, here it is but sorry if it looks like it's not working--it is, I just didn't snap at the right second I guess.

[Tarkus]

I know Beaverton has had them on OR-8 since 2007.

Yes, and they were some of the first in the state, but those are left-turn FYAs.  Cornell/Evergreen is (to my knowledge) the first right-turn FYA in the area.

Just saw a right-turn FYA for the first time in Oregon on Monday <...> It's also opposite a standard left-turn FYA, and the two signals' flashing is out of sync.

I make the assumption that the flashing out of sync is more due to the phase activation in the cycle. I.e. the controller does flashes at a set rate (say 60 flashes/minute) and the flash starts at the moment the phase activates, so if the left arrow starts at 0 seconds and the right arrow starts at 1.5 seconds into the cycle, they are going to be half a second out of sync.

I've noticed differences in flashing between FYAs and flashing hands of pedestrian signals, which I suspect operate similarly.

I drive through that intersection with some regularity--several times a month--and it seems that there are some times when they are (seemingly) perfectly in sync, and others where they're blinking in alternation.  I'm guessing it probably has to do with phasing differences at different times of day, and possibly pedestrian usage (that intersection isn't pedestrian-heavy, but people do occasionally walk down there).  For reference, here's the intersection and approach in question.  The left-turn FYA had been installed by the time Google StreetView came through here, though the McCain fresnel is still in place for the right turn signal.

[Revive 755]

On SB Big Bend Road at MO 100/Manchester Road there is now a flashing yellow right turn arrow.

Side note:  the Missouri MUTCD does not allow FYA's for right turns - see http://epg.modot.mo.gov/index.php?title=902.5_Traffic_Control_Signal_Features_%28MUTCD_Chapter_4D%29#902.5.31_Signal_Indications_for_Permissive_Only_Mode_Right-Turn_Movements_.28MUTCD_Section_4D.22.29 (about 2/3 down from the top of the page)

[brickbuilder711]

I found several installs along Edgewood in Jacksonville, I believe, to have FYAs in a visit earlier this month

[US71]

Texas has a few, including a few along dedicate Left Turn Lanes.

[jakeroot]

Texas has a few, including a few along dedicate Left Turn Lanes.

^^^^

I don't recall ever seeing an electronic version of the "Left Turn Yield" sign...are you aware of why they chose said sign over a permanent "left turn yield on flashing yellow"?

[Tom958]

I am so confused.

While I was in Little Rock for a week, six intersections along Peachtree Road in Brookhaven had their signals redone, or so it appears because they all have the new gold-edged black backplates. All of them are T intersections with two-lane roads ending at Peachtree. The southern four of them have doghouses for left turns, but the northern two have the new (to Georgia) four lens, yellow flashing arrow thing. How was it decided to use two different signal configurations for what really appears to be six instances of the same condition?

[US 41]

What exactly is the problem with this design? Flashing yellow arrows may not be confusing to us, but to the average driver a flashing yellow means go, not yield.

[freebrickproductions]

IIRC, it's to try and eliminate the "Yellow Trap" that occurs with this style of cycle for signals:

[Revive 755]

I don't recall ever seeing an electronic version of the "Left Turn Yield" sign...

The Collinsville District of IDOT used to use those signs for some reason.

A surviving one on IL 161 in the Belleville area

Another in on IL 3 in Dupo

[vdeane]

IIRC, it's to try and eliminate the "Yellow Trap" that occurs with this style of cycle for signals:

I honestly don't understand why one would use that type of signal cycle.  If both directions have semi-protected turns, just give them their own phase.

[Billy F 1988]

There are two FYA signals in Missoula at Brooks Street and Dore Lane and that's all we have at present.

to the average driver a flashing yellow means go, not yield.

Not quite. Yellow, IMO, means go with caution.

[tradephoric]

IIRC, it's to try and eliminate the "Yellow Trap" that occurs with this style of cycle for signals:

I honestly don't understand why one would use that type of signal cycle.  If both directions have semi-protected turns, just give them their own phase.

Split phasing a signal so that the opposing approaches comes on consecutively (I.E. SB through & LT is followed by NB through & LT) is inefficient.  Imagine in the animation, that the left turn movements require 15 seconds to clear, while the through movements require 30 seconds to clear.  In the animation, it would take 45 seconds to service the queued vehicles (15 seconds for SB Thru & LT + 15 seconds for SB & NB through + 15 seconds for NB Thru & LT).  If the signal split phased, it would require 60 seconds to service the queued vehicles (30 seconds for the SB Thru & LT + 30 seconds for the NB Thru & LT).

[Revive 755]

^ Split phasing is even more inefficient if during a cycle there are only through vehicles present but no left turning vehicles.

If the question was more along the lines of 'why not have the left turns go concurrently, but separate from the through movements,' the likely answer is that the agency in charge of the traffic signals was trying to improve coordination and did not see any reason to go to protected only (left on green arrow only) lefts.  Having the NB and SB lefts at different times in the cycle allows the through green indications to be better timed for the respective through movements if said through movements do not arrive concurrently from adjacent signalized intersections.

[roadfro]

What exactly is the problem with this design? Flashing yellow arrows may not be confusing to us, but to the average driver a flashing yellow means go, not yield.

The average driver didn't learn it properly then... green means go, flashing yellow means proceed with caution.

[vdeane]

IIRC, it's to try and eliminate the "Yellow Trap" that occurs with this style of cycle for signals:

I honestly don't understand why one would use that type of signal cycle.  If both directions have semi-protected turns, just give them their own phase.

Split phasing a signal so that the opposing approaches comes on consecutively (I.E. SB through & LT is followed by NB through & LT) is inefficient.  Imagine in the animation, that the left turn movements require 15 seconds to clear, while the through movements require 30 seconds to clear.  In the animation, it would take 45 seconds to service the queued vehicles (15 seconds for SB Thru & LT + 15 seconds for SB & NB through + 15 seconds for NB Thru & LT).  If the signal split phased, it would require 60 seconds to service the queued vehicles (30 seconds for the SB Thru & LT + 30 seconds for the NB Thru & LT).

I was thinking "NB & SB left only, then just the green ball for both directions".  That's how these signals work where I grew up.