Dallas Phasing

[Bryant5493]

^^

Yeah, got a lot of those here.


Be well,

Bryant

[US71]

We actually have those in Ohio...although they're unsigned.  I believe the locals up here call them "pot holes"

Iowa signs their potholes... at least on the dirt roads


So does South Dakota

[shoptb1]

Iowa signs their potholes... at least on the dirt roads

So does South Dakota

I am pretty sure that we would run out of signs here in Ohio if that was the case. 

[burgess87]

We actually have those in Ohio...although they're unsigned.  I believe the locals up here call them "pot holes"

Iowa signs their potholes... at least on the dirt roads

NY does something similar - we have regulatory-style signs (white BG, black legend) that say:

"Seasonal Limited Use Highway - No Maintenance NOV 1-APR 1"

[Michael]

Getting back on topic:

I'm still not sure what someone is supposed to do on a ball/arrow phase.  If only I lived in Dallas...

[rawmustard]

Getting back on topic:

I'm still not sure what someone is supposed to do on a ball/arrow phase.  If only I lived in Dallas...

Well, traffic intending to turn in a direction of a green arrow may do so regardless of the circular indication, whether in a Dallas display or a shared display. If the circular display is red, you can still proceed with any turn indicated by a green arrow. Generally, if you don't see an arrow and your lane isn't controlled by a dedicated turn signal, you do whatever the circular indication indicates.

[US71]

I've been doing a little research and it appears Dallas Phasing also appears in St Louis

http://www.stltoday.com/stltoday/news/columnists.nsf/alongfortheride/story/5F0930567EC485CE8625769E0011EDBD?OpenDocument

I wonder how many other towns do this (too many to count, I'd guess)?

[roadfro]

Getting back on topic:

I'm still not sure what someone is supposed to do on a ball/arrow phase.  If only I lived in Dallas...

It's really quite simple: If you have a green arrow, you go. If you have a green ball, you yield first before you go. If both are on at the same time, the green arrow trumps the green ball. It doesn't matter what the adjacent signals are showing, just the left turn signal head.

[rawmustard]

I've been doing a little research and it appears Dallas Phasing also appears in St Louis

http://www.stltoday.com/stltoday/news/columnists.nsf/alongfortheride/story/5F0930567EC485CE8625769E0011EDBD?OpenDocument

I wonder how many other towns do this (too many to count, I'd guess)?

It seemed to me that there're a lot of yellow traps in St. Louis based on that column, not necessarily Dallas phasing. The gist of this seems more to be Missourans' reluctance to enter an intersection on a permissive turn. I'm still scratching my head over what much of the commenters are saying. 

As for other locations for Dallas phasing, no jurisdiction that I know of in Michigan has ever done it, and considering the state was (somewhat surprisingly) a fairly early adopter of the flashing-yellow arrow and the 2009 MUTCD's outright prohibition on Dallas phasing, I highly doubt I'll ever see it here.

[Michael]

Getting back on topic:

I'm still not sure what someone is supposed to do on a ball/arrow phase.  If only I lived in Dallas...

It's really quite simple: If you have a green arrow, you go. If you have a green ball, you yield first before you go. If both are on at the same time, the green arrow trumps the green ball. It doesn't matter what the adjacent signals are showing, just the left turn signal head.

I get that, but I'm talking about a doghouse dedicated to a left turn lane, shielded from view of thru traffic.

[roadfro]

As for other locations for Dallas phasing, no jurisdiction that I know of in Michigan has ever done it, and considering the state was (somewhat surprisingly) a fairly early adopter of the flashing-yellow arrow and the 2009 MUTCD's outright prohibition on Dallas phasing, I highly doubt I'll ever see it here.

If I recall correctly, Michigan was one of the states that had developed a different display for PPLT. I want to say it was a 3-section arrow display, maybe with flashing red.  Dallas Phasing wouldn't have been considered then, because 5-section faces weren't used.

I'm still not sure what someone is supposed to do on a ball/arrow phase.  If only I lived in Dallas...

It's really quite simple: If you have a green arrow, you go. If you have a green ball, you yield first before you go. If both are on at the same time, the green arrow trumps the green ball. It doesn't matter what the adjacent signals are showing, just the left turn signal head.

I get that, but I'm talking about a doghouse dedicated to a left turn lane, shielded from view of thru traffic.

So am I.  The signal indications don't mean anything different just because they are in a separate face that only the left turn lane sees.

If it's any consolation, one of the primary reasons for switching to the FYA display is to eliminate confusion experienced by many drivers when encountering both arrow and circular indications simultaneously in a signal face--especially when a red ball and a green arrow are on at the same time.

[rawmustard]

If I recall correctly, Michigan was one of the states that had developed a different display for PPLT. I want to say it was a 3-section arrow display, maybe with flashing red.  Dallas Phasing wouldn't have been considered then, because 5-section faces weren't used.

Yes, Michigan was big on the flashing red ball for PPLT display. From what I've heard or read, it was always meant to be a yield and not necessarily a full stop despite the legal definition of flashing red. Five-section heads didn't really start appearing in the state until the mid-to-late 1980s. I can still recall that the Kalamazoo Gazette ran an article when the city of Portage introduced the doghouse to replace most of their intersections which had been using protected-only lead lefts (and a few years before that, those intersections were using flashing red lag lefts). I just marvel at how quickly Michigan decided to join the flashing yellow arrow trend, because they've been slow to catch on to other trends (e.g., the solid yellow arrow ).

[US71]

UPDATE:
Fayetteville, AR has NO interest in upgrading to Flashing Yellow Arrows. They see no need.

Bentonville will be upgrading several signals along AR 102 to FYA's, but probably not until next year.

[roadfro]

There's no requirement to upgrade existing signals to FYA. However, new signals are supposed to use FYA and signals are supposed to be upgraded to FYA is modified or reconstructed.  Existing 5-section heads can also remain if they aren't separate heads and the circular indications always display the same as the through signals.

For many jurisdictions, this likely means that there will be no immediate changeover to FYA from 5-section PPLT heads (mainly because Dallas Phasing isn't that widespread). I imagine many agencies will put off changing over for a while, as many older signal controllers either cannot implement flashing yellow arrow phasing or require software reprogramming to do so. Furthermore, changing to FYA requires a capital expense for new signal heads and controller cabinet modifications, money that many public entities are likely holding on to unless absolutely necessary.


With that said, it's good to see more agencies considering switching to FYAs. I've been told Nevada DOT is considering implementation of FYAs statewide.  It's an issue that they will have to work out with the various cities and counties, as those agencies are the ones that maintain traffic signals (even on state highways).  I believe Las Vegas and Clark County have been somewhat resistant to changing to FYAs, preferring a modified use of the 5-section doghouse in switching between protected and permitted modes.  The only installations of FYA I'm aware of in Nevada are two signals in Carson City (on Fairview Drive/Temp US 395-50).

[CL]

http://ow.ly/1nVUF

Although Salt Lake City has been experimenting with these for a few years, UDOT is now officially implementing signals with Dallas phasing.

[roadfro]

I posted in the SW section that Nevada DOT is looking at statewide implementation of FYA. No mention of the phase-in timeline or any immediate retrofit/upgrade plans.

[burgess87]

I've seen several FYA left turn setups in the Charlotte, NC area while I've been down here (for only about a week).

[AZDude]

Man, I'm glad I read this.  I would have thought that the light was malfunctioning.  I wouldn't have thought that I had a protected left turn though.

[realjd]

I've seen several FYA left turn setups in the Charlotte, NC area while I've been down here (for only about a week).

Last time I was stick in that dump of a town Fayetteville, NC, they had FYA's as well.

[roadfro]

Man, I'm glad I read this.  I would have thought that the light was malfunctioning.  I wouldn't have thought that I had a protected left turn though.

I think you mean permitted left turn, if referring to a green ball or flashing yellow arrow.

[AZDude]

Man, I'm glad I read this.  I would have thought that the light was malfunctioning.  I wouldn't have thought that I had a protected left turn though.

I think you mean permitted left turn, if referring to a green ball or flashing yellow arrow.

In a way, yes because I would have not thought of it as a green arrow. 

As stated by US 71, a driver thought they had a protected left turn (because they saw the green ball, thinking it was the same as a green arrow) and crashed into an oncomming car. 

If I were at that intersection at that time, I would have stayed there and waited as if it were a regular red light because I would have thought the signal was malfunctioning.

[florida]

This took me a little while to finish up, but I hope you all will find it helpful.  I've created a short video that explains in a graphic format the differences between the various forms of protected/permitted left turn controls, including Dallas Phasing.

By no means am I a whiz with video capture and online videos, so I hope it works okay. Here it is: http://www.youtube.com/watch?v=KPKjcPI5Sko

I did enjoy this video because it explained everything perfectly, as I've never heard of this type of setup before. Great job, roadfro! It's a good thing Dallas Phasing is not used down here.

[shoptb1]

This took me a little while to finish up, but I hope you all will find it helpful.  I've created a short video that explains in a graphic format the differences between the various forms of protected/permitted left turn controls, including Dallas Phasing.

By no means am I a whiz with video capture and online videos, so I hope it works okay. Here it is: http://www.youtube.com/watch?v=KPKjcPI5Sko

This video is very good as it helps explain the differences.  In my opinion, the Flashing Yellow Arrow (FYA) is the best visual descriptor to the driver to help them from confusing the green ball from the green arrow intentions. 

[florida]

There is a pseudo-variation of this in Fort Lauderdale, but it's only used at U-turn signals (dotted along US 1 mostly). The red phase will flash, and you can either come to a complete stop to wait for traffic to clear. If you're there too long, it will change to a solid green arrow to make your U-turn (opposing traffic will be stopped of course), then a solid yellow arrow, and back to flashing red.

[Kacie Jane]

I noticed a couple of FYA assemblies in Marysville, WA for the first time yesterday, not sure how recent a development that is.

The "variation" (if you can call it that) that I've seen most often in this part of the country doesn't use any special phasing. Rather, at several intersections where the intersecting street is only one side of the road (i.e. T-intersection), they just tack on a sign over the left turn lane that says "Stop on (red ball), then left turn permitted".  Still requires you to stop instead of yield, but it does the job.