Traffic signal

[jakeroot]

But if they are for right turn signals, they are forward Utahs.

Such signals are standard design here, Sweden's full of Utahs. 

And that's a point I made in my original post: the so-called "side-by-side" in-line style is the standard style used across the globe. Centralising the red orb seems to be an American practice (not Canadian either, since Canada places all arrows and orbs in-line with each other, whether horizontal or vertical). In this way, Colorado, West Virginia (didn't know about this one), and places in New York are actually more normal with respect to other places across the globe.

As I mentioned before, I much prefer the "Utah" style since the arrows are "tacked on" to the correct side of the three orbs: if it's a left turn, they're tacked on to the left side of the three orbs; if for right turns, they're tacked onto the right side. In the end, it may not make any functional difference, but my OCD prefers this as it's just more logical. Plus I'm not really keen on the "peaky" look of doghouse signals. But that's entirely personal.

[jakeroot]

Okay, there's a lane split and no crossing on the main road.  Why does the main road have a signal with three signal heads?  Why isn't it just a green-T?

While the green-T is the most proper signal in this instance, it is not necessarily a bad thing to put up a regular signal.  Perhaps it was easier for the signal department to put up a normal signal.  Also, just because it is possible to signalize red and yellow, doesn't mean that it actually does.

I recall this signal in Washington DC at Pennsylvania and Constitution.

https://www.google.com/maps/@38.8917729,-77.0166988,3a,75y,103.53h,72.12t/data=!3m7!1e1!3m5!1smgFSWR76quUpmfR9xMPTLQ!2e0!5s20161001T000000!7i13312!8i6656

Notice that there seems to be no reason for straight traffic to ever stop.  For the longest time, that was in fact the case, and the signal showed green continuously even though it used a normal signal head.

So why does it turn red now?  When the median bike lanes were installed, they used the straight signals to control the bike lane traffic as well.  As these are in conflict with the left turn, they have to be red when the left turn gets a green arrow.  Could this be addressed with bike signals?  Probably, but given that the signals are all close to each other, a bike signal may be confused with the straight signal and should probably not be used in the interests of safety.  In a normal intersection, the straight signals could be kept on the right side with the use of mast arms, but given the direct view of the Capitol, mast arms are not allowed on Pennsylvania, despit the street's width, so that the view of the building is not impacted.

I've long found that intersection & signal very confusing. I know why it operates the way it does (because of the conflicts with the bike lane), but the advent of modern bike signals should preclude the operation as-is. Right now, I can't even begin to count how many cars I've seen run that light. There's no obvious conflict, no crosswalk or anything. Seems like most drivers assume it's a mistake or something.

They could have just mounted the bike signal below the other signals, as they do in Seattle. To keep from cluttering, backplates could be discarded on the bike signals, since they're low enough to not have to worry about sun glare.

[STLmapboy]

Unrelated
When I went to Memphis, I was taken aback by the age of some of the signals. I've heard there are more of these through the south (3/4 section original signals). Does anyone else know where more might be? I drove by one in Tuscumbia, AL, by the Hellen Keller birthplace, and the signal may or may not remember when she was alive.

[jakeroot]

I drove by one in Tuscumbia, AL, by the Hellen Keller birthplace, and the signal may or may not remember when she was alive.

I immediately started laughing, but you may actually be right

When I went to Memphis, I was taken aback by the age of some of the signals. I've heard there are more of these through the south (3/4 section original signals).

Definitely older signals in Memphis, although Memphis is much better at placing the signals than the rest of Tennessee.

As a side-note: TN also appears to be a user of side-by-side 5-section signals.

[STLmapboy]

I drove by one in Tuscumbia, AL, by the Hellen Keller birthplace, and the signal may or may not remember when she was alive.

I immediately started laughing, but you may actually be right

When I went to Memphis, I was taken aback by the age of some of the signals. I've heard there are more of these through the south (3/4 section original signals).

Definitely older signals in Memphis, although Memphis is much better at placing the signals than the rest of Tennessee.

As a side-note: TN also appears to be a user of side-by-side 5-section signals.

Noticed that too (also present in Nebraska), although many Memphian intersections (especially inside the 40/240 beltway) use the "homemade do-it-yourself" doghouse--two 12-inch arrows tacked next to an 8-inch standard RYG that's been there a while longer. Example. New York City seems to use this as well. There are none around me in St Louis, and also no differently-sized signal lights (no 12-8-8s, for example). At least that I know of.

[ErmineNotyours]

Okay, there's a lane split and no crossing on the main road.  Why does the main road have a signal with three signal heads?  Why isn't it just a green-T?

While the green-T is the most proper signal in this instance, it is not necessarily a bad thing to put up a regular signal.  Perhaps it was easier for the signal department to put up a normal signal.  Also, just because it is possible to signalize red and yellow, doesn't mean that it actually does.

[snip]

After I made my post, I realized they could put a red on the through direction to stop traffic for emergency vehicles.

[STLmapboy]

Check out this old gantry-mounted traffic light assembly in Daly City, CA.

[ErmineNotyours]

I may have posted this before: gantry sign and traffic light assembly, Oregon City, Oregon.

[US 89]

Here's a weird traffic light I recently saw on SR 209 in Sandy, Utah:



Until now, I had never seen a double red arrow in Utah, and I don't think I've seen a double red arrow on top of a FYA anywhere.

[jakeroot]

^^^^
That's gotta be a one-off, in terms of vertical alignment with a double red. TX has quite a few 5-section FYAs with double reds, but the whole signal is aligned horizontally.

[Rothman]

Here's a weird traffic light I recently saw on SR 209 in Sandy, Utah:



Until now, I had never seen a double red arrow in Utah, and I don't think I've seen a double red arrow on top of a FYA anywhere.

Right by my in-laws' house.

[jakeroot]

Right by my in-laws' house.

Congrats!

[Revive 755]

^^^^
That's gotta be a one-off, in terms of vertical alignment with a double red. TX has quite a few 5-section FYAs with double reds, but the whole signal is aligned horizontally.

Wouldn't surprise me if there's one someone in the Carolinas.  They do occasionally use double red arrow heads for protected only left turns.

[Amtrakprod]

^^^^
That's gotta be a one-off, in terms of vertical alignment with a double red. TX has quite a few 5-section FYAs with double reds, but the whole signal is aligned horizontally.

Wouldn't surprise me if there's one someone in the Carolinas.  They do occasionally use double red arrow heads for protected only left turns.

I was just going to say I've seen one somewhere in SC, in the Hilton Head area.


iPhone

[STLmapboy]

^^^^
That's gotta be a one-off, in terms of vertical alignment with a double red. TX has quite a few 5-section FYAs with double reds, but the whole signal is aligned horizontally.

Wouldn't surprise me if there's one someone in the Carolinas.  They do occasionally use double red arrow heads for protected only left turns.

I was just going to say I've seen one somewhere in SC, in the Hilton Head area.


iPhone

It's common all through the southeast, the T-shaped protected-only left. Here are some examples from Georgia. All four were installed after 2015. Admittedly, I've never seen a T-shaped flashing yellow, though seeing a T-shaped signal west of the Mississippi is in itself notable.

[Big John]

^^ Georgia has a policy of a minimum of 2 red arrows on a protected-only left.  The usual method is 2 3-section signals, but the T-shaped signal can be used if the former can't be used.

[jakeroot]

^^ Georgia has a policy of a minimum of 2 red arrows on a protected-only left.  The usual method is 2 3-section signals, but the T-shaped signal can be used if the former can't be used.

You learn something new every day.

Then again, by that logic, Georgia's single-lane FYA installations must use the double red arrow? Or have they all been two signals placed directly next to each other*?

* why exactly they end up next to each other, like in DE, rather than one centered over the lane and one off to the left, is beyond me. smh.

[Rothman]

Right by my in-laws' house.

Congrats!

Thanks!

[mrsman]

^^ Georgia has a policy of a minimum of 2 red arrows on a protected-only left.  The usual method is 2 3-section signals, but the T-shaped signal can be used if the former can't be used.

You learn something new every day.

Then again, by that logic, Georgia's single-lane FYA installations must use the double red arrow? Or have they all been two signals placed directly next to each other*?

* why exactly they end up next to each other, like in DE, rather than one centered over the lane and one off to the left, is beyond me. smh.

I would think that the reason would be cost.  In span wire jurisdictions, it is far cheaper to just hang another signal on the wire, then to add a signal on a pole in the far corner.  There may also be a concept of trying to align one singal face per lane. (And in that sense, it may throw drivers off to see the left arrow signal face over a lane that goes in the other direction.)

In many respects, the 4 aspect FYA signal is the 3 aspect protected only signal with a FYA added between the middle and bottom aspect.  Theoretically, every permutation of the 3 aspect protected only signal should be present with the FYAs as well.  So it is surprising in jurisdictions where the T-shaped 3 aspect protected only signal (with two red arrows) is common, taht the equivalent for the FYAs is not also common, like in the posted example from Utah.  Maybe the FYAs are generally installed in pairs so there are at least two FYA signal faces in the operating direction.

As Big John said, two red arrows are required in GA, in some way or fashion.  Two separate signal heads or at minimum two red arrows on the same signal head.  This is probably to ensure redundancy in case one of the red arrows burns out.  I wonder if the same rule applies in Utah.

I also wonder if there are any situations that use the T-shaped signal twice in the same direction.  In my experience, the T-shaped signals that I have encountered have all been the only signal face in that direction.  And based on the above, it would seem that if there are two separate left signal heads, there would simply be no reason for a T shaped signal.

[US 89]

As Big John said, two red arrows are required in GA, in some way or fashion.  Two separate signal heads or at minimum two red arrows on the same signal head.  This is probably to ensure redundancy in case one of the red arrows burns out.  I wonder if the same rule applies in Utah.

I also wonder if there are any situations that use the T-shaped signal twice in the same direction.  In my experience, the T-shaped signals that I have encountered have all been the only signal face in that direction.  And based on the above, it would seem that if there are two separate left signal heads, there would simply be no reason for a T shaped signal.

That rule almost certainly does not apply in Utah - in fact, I'd bet around half of all protected lefts in Utah have just one signal head with one red arrow. That's the only double arrow I've ever seen in Utah, and unless it's a dual left, there aren't that many intersections that have an additional signal head.

That wouldn't even be the reason for the double red, though - in this case, there is an additional signal head on the far side.

My bet is they want to put extra emphasis on the red arrow, maybe because there's been a history of red arrow-running crashes at that intersection. Utah does have a fair amount of intersections where there are double red lights, which UDOT uses on occasion at intersections where they want to minimize red light running or emphasize a red light. Most of them are along the Mountain View Corridor (like this one), but I've seen them scattered elsewhere around the state.

[mrsman]

As Big John said, two red arrows are required in GA, in some way or fashion.  Two separate signal heads or at minimum two red arrows on the same signal head.  This is probably to ensure redundancy in case one of the red arrows burns out.  I wonder if the same rule applies in Utah.

I also wonder if there are any situations that use the T-shaped signal twice in the same direction.  In my experience, the T-shaped signals that I have encountered have all been the only signal face in that direction.  And based on the above, it would seem that if there are two separate left signal heads, there would simply be no reason for a T shaped signal.

That rule almost certainly does not apply in Utah - in fact, I'd bet around half of all protected lefts in Utah have just one signal head with one red arrow. That's the only double arrow I've ever seen in Utah, and unless it's a dual left, there aren't that many intersections that have an additional signal head.

That wouldn't even be the reason for the double red, though - in this case, there is an additional signal head on the far side.

My bet is they want to put extra emphasis on the red arrow, maybe because there's been a history of red arrow-running crashes at that intersection. Utah does have a fair amount of intersections where there are double red lights, which UDOT uses on occasion at intersections where they want to minimize red light running or emphasize a red light. Most of them are along the Mountain View Corridor (like this one, but I've seen them scattered elsewhere around the state.

Interesting.  RR-Y-G lights for emphasis.  Kind of similar to the 12-8-8 that you see in some places, especially Canada, to emphasize the red signal.  I guess there is no standard larger lens than 12", so just place two reds instead.

[Revive 755]

Most of them are along the Mountain View Corridor (like this one, but I've seen them scattered elsewhere around the state.

I was wondering if anyone was actually using doghouse bicycle signals . . .

[mrsman]

Most of them are along the Mountain View Corridor (like this one, but I've seen them scattered elsewhere around the state.

I was wondering if anyone was actually using doghouse bicycle signals . . .

I was curious about that as well.  What could the 5 aspects possibly be, unless we are giving a protected left turn phase for bikes?

[US 89]

Most of them are along the Mountain View Corridor (like this one, but I've seen them scattered elsewhere around the state.

I was wondering if anyone was actually using doghouse bicycle signals . . .

I was curious about that as well.  What could the 5 aspects possibly be, unless we are giving a protected left turn phase for bikes?

I have no idea how those work, but there are a few of those on Mountain View. From what I've been able to tell driving by them, the indications appear to be:

-top: red bicycle
-top left: yellow bicycle
-bottom left: green straight arrow
-top right: yellow right arrow
-bottom right: green right arrow

[mrsman]

Most of them are along the Mountain View Corridor (like this one, but I've seen them scattered elsewhere around the state.

I was wondering if anyone was actually using doghouse bicycle signals . . .

I was curious about that as well.  What could the 5 aspects possibly be, unless we are giving a protected left turn phase for bikes?

I have no idea how those work, but there are a few of those on Mountain View. From what I've been able to tell driving by them, the indications appear to be:

-top: red bicycle
-top left: yellow bicycle
-bottom left: green straight arrow
-top right: yellow right arrow
-bottom right: green right arrow

That actually makes sense.  Straight bikes can go with the straight light, but not when the green left arrow for cars is lit.  Left turns will need a protective phase when bikes are stopped.  Bike right turns will need a protective phase when cars are stopped.

How many bikes do they expect through here give these signals?

Nexus 5X