HAWK Thread

[Dirt Roads]

Speaking of Hybrid Beacons and railroad crossings... what about them actually being used at a railroad crossing, either in tandem with existing signals or as the actual warning devices? Two examples I can think of:

W Jefferson Ave and Zug Island Rd in Detroit MI - there are no actual railroad (level) crossing signals here, the hybrid beacons ARE the actual level crossing signals. Past GSV suggested they replaced traditional RYG signals on the mast arm around 2017. Wonder if their sequence is very similar to how the United Kingdom and Ireland does their level crossings. Example of what I mean for a sequence:

https://www.youtube.com/watch?v=7KVOPU5MQrw

These appear to function more like a traditional railroad crossing signal than a HAWK -- there is an added yellow phase before the alternating flashing reds, but there is no flashing yellow or solid red phases.  Maybe some genius from the county or city Design department got involved.

The bigger issue I see:  Am I nuts, or are both gates on the wrong sides of the road?

You're nuts. You missed that this is in the UK or Ireland..

To be fair, the "another train coming" sign is on the wrong side of the road. You'd never see a sign like that on the left side of a 2-lane road in the US, would you?

You are correct, that the "Another Train Coming" sign would be placed on the right side here in the United States, but the placement of that sign is to warn someone running around the gates (in the opposite lane not to enter the crossing.  Assuming that the offending vehicle is passing a string of traffic waiting at the extended gate, it is placed and aimed correctly.  But I strongly believe that any "Another Train Coming" sign that is placed on the opposite side of the road should be aimed at the second car behind the gate (ergo, about 30 feet in front of the gate tip).  After many years of discussion here in the United States, the "Another Train Coming" sign is finally getting formalized in the most recent MUTCD changes.  (I haven't bothered looking this up yet, but this subthread has got my attention).

[SignBridge]

Re: the earlier above photo of the HAWK installation in Detroit, I discovered that the MUTCD does permit (Sec. 8C.09.01) traffic control signals to be used instead of flashing light signals at industrial grade crossings and other locations where train movements are very slow such as switching operations. The crossing in the photo may fit that description.

But so far I haven't seen any provision specifically authorizing HAWK beacons or Emergency Vehicle Hybrid Beacons at railroad crossings. But they might fall under the Manual's general category of traffic control signals; so who knows? Stay tuned. 

[Dirt Roads]

Re: the earlier above photo of the HAWK installation in Detroit, I discovered that the MUTCD does permit (Sec. 8C.09.01) traffic control signals to be used instead of flashing light signals at industrial grade crossings and other locations where train movements are very slow such as switching operations. The crossing in the photo may fit that description.

But so far I haven't seen any provision specifically authorizing HAWK beacons or Emergency Vehicle Hybrid Beacons at railroad crossings. But they might fall under the Manual's general category of traffic control signals; so who knows? Stay tuned.

I wonder if this is a test application.  One of the issues at many urban grade crossings is that a railroad employee (typically the brakeman, sometimes the conductor) needs to manually flag the crossing.  In some cities, it has been difficult for the [flagger] to step out into traffic because of aggressive drivers who don't want to wait (and know that they don't have to if they get in the crossing before the [flagger] that just got out of the locomotive (or caboose, in certain cases).  In that case, a HAWK signal serves the purpose of protecting the [flagger] and once the train is on the move, the HAWK signal is irrelevant.  In gentler cities where traffic was light enough, the [flagger] simply rode out on the front of the locomotive and waved traffic to a stop before the train crossed.

[jeffandnicole]

To be fair, the "another train coming" sign is on the wrong side of the road. You'd never see a sign like that on the left side of a 2-lane road in the US, would you?

Well, it's on the "other" side, not the wrong side.

You wouldn't also see white lines separating the flow of traffi in the US, or gates just on the "wrong side" either.

Although we have so many signs here I'm the US on the wrong side anyway, sometimes it's tough to tell.

[Revive 755]

Re: the earlier above photo of the HAWK installation in Detroit, I discovered that the MUTCD does permit (Sec. 8C.09.01) traffic control signals to be used instead of flashing light signals at industrial grade crossings and other locations where train movements are very slow such as switching operations. The crossing in the photo may fit that description.

But so far I haven't seen any provision specifically authorizing HAWK beacons or Emergency Vehicle Hybrid Beacons at railroad crossings. But they might fall under the Manual's general category of traffic control signals; so who knows? Stay tuned.

From FHWA's interpretation ""4(09)-2(I) - Hybrid Beacons Adjacent to Grade Crossings":

A Hybrid Beacon is defined in Section 1A.13 as a "special type of beacon" rather than a special type of traffic control signal. Therefore, neither a Pedestrian Hybrid Beacon (PHB) nor an Emergency-Vehicle Hybrid Beacon (EVHB) is considered to be a traffic control signal.

[Scott5114]

The railroader in me wants to remind everyone that the flashing railroad signals is meant to represent the left and right [stops] of a wig-wag, which simulates a railroad flagger swinging a red lantern back-and-forth.  Which indeed, both the wigwag and the flagman use constant red signals.  But you'all are entirely correct, the flashing red signals should have a consistent aspect (interpreted meaning):  "stop while flashing".

Maybe the correct solution, then, is to use LEDs to create a wig-wag-like animation for railroad crossings, where the light moves in an arc like a wig-wag does.

[US 89]

To be fair, the "another train coming" sign is on the wrong side of the road. You'd never see a sign like that on the left side of a 2-lane road in the US, would you?

Well, it's on the "other" side, not the wrong side.

You wouldn't also see white lines separating the flow of traffi in the US, or gates just on the "wrong side" either.

Although we have so many signs here I'm the US on the wrong side anyway, sometimes it's tough to tell.

Do we? The only signs I routinely see on the left on two-way streets in the US are the "no passing zone" ones and those yellow signs with chevrons/arrows that they use on sharp enough curves.

Re: the earlier above photo of the HAWK installation in Detroit, I discovered that the MUTCD does permit (Sec. 8C.09.01) traffic control signals to be used instead of flashing light signals at industrial grade crossings and other locations where train movements are very slow such as switching operations.

If you're looking for a real-world example of this, there are at least two of them in Salt Lake City.

[wanderer2575]

Speaking of Hybrid Beacons and railroad crossings... what about them actually being used at a railroad crossing, either in tandem with existing signals or as the actual warning devices? Two examples I can think of:

W Jefferson Ave and Zug Island Rd in Detroit MI - there are no actual railroad (level) crossing signals here, the hybrid beacons ARE the actual level crossing signals. Past GSV suggested they replaced traditional RYG signals on the mast arm around 2017. Wonder if their sequence is very similar to how the United Kingdom and Ireland does their level crossings. Example of what I mean for a sequence:

https://www.youtube.com/watch?v=7KVOPU5MQrw

These appear to function more like a traditional railroad crossing signal than a HAWK -- there is an added yellow phase before the alternating flashing reds, but there is no flashing yellow or solid red phases.  Maybe some genius from the county or city Design department got involved.

The bigger issue I see:  Am I nuts, or are both gates on the wrong sides of the road?

You're nuts. You missed that this is in the UK or Ireland..

My bad; I thought this was the Zug Island Road crossing.  The Google Maps link wasn't working for me at the time.  I withdraw my comments.

[mrsman]

I find it incredibly irritating that the "old style" LA crossing isn't the standard for signalized crossings everywhere: no blank displays, no stupid wig-wags, no enormous signs explaining everything; just regular phasing that everyone understands and would see on a regular basis.

The fact that the HAWK won out over this is astounding to me. Even LADOT is installing HAWKs now, even though they are already invented a far superior design decades ago. It's this kind of stuff that truly makes me question some engineers. Or whoever is running the show.

The L.A. signal is probably the best implementation of pedestrian signal. 

As stated above, easy to understand and definitely meets expectations.

These are only installed in mid-block (or equivalent)* situations.  A full intersection should get a full signal to avoid confusion with respect to side street traffic.

They are fail-safe.  To the extent that they are not a standard RYG, and to the extent that a driver may be confused, the confusion will cause a driver to wait until the green.  Delaying traffic, not injuring pedestrians.

My one recommendation would be to start with a brief, 5 second, solid red phase.  Many of these are so old that I believe the technology didn't allow for a solid red sequence followed by a flashing red sequence.  Technology now certainly allows it, as we can see with HAWKs, so these signals should also be modified to allow for a brief solid red at the beginning of the pedestrian crossing.

* Equivalent situations.  Treated as mid-block but still have some element of cross-traffic to be concerned with:

https://www.google.com/maps/@34.0572807,-118.2404379,3a,75y,255.22h,81.02t/data=!3m6!1e1!3m4!1st1kDYE-8PyhJyRgIVGtQOg!2e0!7i16384!8i8192

Spring St at US 101 NB exit ramp.  On Spring Street, just south of the crosswalk, there is an exit ramp from the freeway that meets Spring.  All traffic from the exit ramp faces a stop sign and all must turn right.   Having used this ramp, I can tell you that a full signal would be helpful to give the exit traffic a protected phase.  It is difficult to make this right, and the stop and go  feature of the flashing red actually makes it harder for cross-street rights, since the available gap time is shorter.


https://www.google.com/maps/@34.0885889,-118.3778148,3a,37.5y,64.29h,85.65t/data=!3m6!1e1!3m4!1siFGNYZlF8RAAePSP0YPKYA!2e0!7i16384!8i8192

West Knoll Dr at Santa Monica Blvd.  While this is in West Hollywood, the signal operates in a simila fashion to the LADOT standard.  Again, we have a cross street that only allows for RIRO, that is just after the cross walk.  So with respect to SM Blvd traffic, this is a mid-block location, and the side street, being downstream from the crosswalk, doesn't really interact with the pedestrians that are crossing SM Blvd.  So this is an appropriate way to turn a T intersection with a small street into an intersection that is appropriate for the (better version of the) HAWK signal.  Obviously, West Knoll Dr has less traffic than the US 101 off-ramp, so I don't believe there is any general warrant for a signal here, other than for pedestrians.

I would even venture to say that more intersection should be designed this way.  If the main street has significant pedestrian draw, certain side streets, that don't warrant a vehicular signal, should be transfomed into RIROs (especially at T-intersections).  Provide a cross-walk that is upstream from the side street, and have the crosswalk controlled by an LADOT Ped XING signal.  You provide a safe crossing at every intersection, while avoiding major delays that would be induced on the main street with a full signal at every intersection.  You also minimize side street interaction, which HAWKS and LADOT Ped XING signals are not really designed to address.

[mrsman]

go to 178 in bakersfield they have a HAWK the first one in bakersfield and in kern county

Well, that was vague.

Here is the specific location:  https://goo.gl/maps/kWQoVka4t4pyXoSQ6

Take a look at this intersection of 24th/Pine in Bakersfield.  One thing that should be pointed out is that the pedestrian crossing is a Z-shaped crossing.  You cross the south side of 24th on the west side of Pine, then walk "across" Pine along the 24th median, and then cross the north side of 24th on the east side of Pine.  If the southside of the intersection were reopened (GSV currently shows a cul-de-sac), it would ensure that the right turn movements of Pine onto 24th would all be downstream of the pedestrian crossing.  So the crosswalk would not interfere with any side street movements.  So other than the general problems with HAWKs, this is a good design for a pedestrian crossing signal, even if there is no warrant for Pine street auto traffic.  [My prefernce is the L.A. style RYG signal.]

The bus on GSV reminds me that this would be a great place for a bus stop.  If someone lives in this neighborhood and is taking the bus, they will have to cross 24th street at least once (either on  their outgoing trip or on their return trip).  A bus stop necessarily will create a pedestran crossing demand and bus stops should be placed in locations where pedestrian crossing is made safer.

[SignBridge]

I still can't believe the FHWA is okay with dark traffic signals, when they were prohibited since the year one. Oh wait, these aren't traffic control signals as defined in the Manual. They are Beacons which are a different set of rules.

Yeah right; like the average driver knows the technical difference......

[kphoger]

Oh wait, these aren't traffic control signals as defined in the Manual. They are Beacons which are a different set of rules.

Yeah right; like the average driver knows the technical difference......

This is further reason that they should only be used mid-block, but drivers encounter dark beacons away from intersections all the time.  Think of a stoplight warning sign with an attached double yellow beacon:  some of them remain dark until the light is about to change.

[SignBridge]

Oh wait, these aren't traffic control signals as defined in the Manual. They are Beacons which are a different set of rules.

Yeah right; like the average driver knows the technical difference......

This is further reason that they should only be used mid-block, but drivers encounter dark beacons away from intersections all the time.  Think of a stoplight warning sign with an attached double yellow beacon:  some of them remain dark until the light is about to change.

Kphoger, the difference is that the stoplight warning beacon is just an advisory/caution beacon. Whereas the HAWK is a regulatory signal just like a normal traffic light, so in my opinion the FHWA shouldn't be calling it a beacon. They define it as a beacon because it doesn't meet their definition of a traffic control signal which operates continuously alternating the right-of-way between at least two approaches.

And again if the Feds think the average driver is going to make that distinction between different types of traffic lights, well good friggin' luck. It'll be interesting to see how many drivers stop at dark HAWK signals at night thinking it's a defective traffic light that's completely out.

[hotdogPi]

And again if the Feds think the average driver is going to make that distinction between different types of traffic lights, well good friggin' luck. It'll be interesting to see how many drivers stop at dark HAWK signals at night thinking it's a defective traffic light that's completely out.

Around here, people don't stop at dark signals if it's clearly the priority road.

[cjw2001]

Oh wait, these aren't traffic control signals as defined in the Manual. They are Beacons which are a different set of rules.

Yeah right; like the average driver knows the technical difference......

This is further reason that they should only be used mid-block, but drivers encounter dark beacons away from intersections all the time.  Think of a stoplight warning sign with an attached double yellow beacon:  some of them remain dark until the light is about to change.

Kphoger, the difference is that the stoplight warning beacon is just an advisory/caution beacon. Whereas the HAWK is a regulatory signal just like a normal traffic light, so in my opinion the FHWA shouldn't be calling it a beacon. They define it as a beacon because it doesn't meet their definition of a traffic control signal which operates continuously alternating the right-of-way between at least two approaches.

And again if the Feds think the average driver is going to make that distinction between different types of traffic lights, well good friggin' luck. It'll be interesting to see how many drivers stop at dark HAWK signals at night thinking it's a defective traffic light that's completely out.

A new Hawk signal went in at a trail crossing near my house, which was the first in the immediate area.   On Nextdoor from the chats you thought it was going to be the end of the world.  However once it was activated the controversy disappeared, the drivers quickly adjusted, and the crossing is now working well.   Before the Hawk went in there was a constant issue with pedestrians crossing without yielding to oncoming traffic and with cars suddenly stopping at the trail crossing for no reason.  Now everybody is happy.  These things actually work.

[kphoger]

As far as I can tell, the downsides presented on here come in two forms:

(1)  Some people stay stopped longer than they actually need to, because they don't realize they can proceed against a flashing red.  This unnecessary stoppage would likely still exist with a standard R-Y-G signal, because the flashing red phase would just be part of the solid red phase instead.  Also, pedestrian signals are installed for safety reasons, and people not going right away presents no danger to a pedestrian.  Furthermore, this issue should dwindle with time:  as more and more drivers see someone proceed against the flashing red, they'll realize it's permitted and do likewise.

(2)  Some people stop at them even when they're dark.  I suspect this phenomenon is exceedingly rare, to the point that the objection is meaningless.  For one thing, as |1| pointed out, a whole heck of a lot of people don't even stop at dark signals at intersections.  But for another thing, I've never once seen a driver stop at a dark HAWK signal beacon signal.  Even if it actually were common–which it isn't–what's the worst that would happen?  People would get annoyed and honk their horns.

[mrsman]

Before MD adopted the HAWK signal, they used these emergency signal type displays for ped crossings.  [These are pretty common around fire stations.]  Many are still out there.

THe default phase is having the bottom signal flash yellow.  The bottom signal is usually 8", while the other signals are 12".

After a ped pushes the button, the bottom signal flashes faster as a warning that the signal has been activated.

Then, the middle signal, which is a solid yellow comes on.

Then, a solid red comes on, while the pedestrians are permitted to cross.

Here's an example:

https://www.google.com/maps/@39.0241262,-77.0182096,3a,75y,140.7h,91.68t/data=!3m6!1e1!3m4!1slObc4XTFixNlR09UDBibnw!2e0!7i16384!8i8192


IMO, this is the worst of all worlds.  The lack of familiarity by using a unique signal combined with a solid red that keeps drivers waiting even when pedestrians have cleared.  Another down side is that many drivers go by and only see the flashing yellow, so even if they drive down the street many times, they may not be aware that the signal can come to life each time that a pedestrian pushes the button.  I have seen too many cars just run through these things, even when the red light comes on. 

Occasionally, DOT will put in a warning beacon ahead of this ped crossing.  The following beacon will flash when the upcoming emergency signal has been triggered.

https://www.google.com/maps/@39.0389018,-77.0416349,3a,75y,320.57h,76.39t/data=!3m6!1e1!3m4!1s5O1jVT3zYBpirfHPOkBWKQ!2e0!7i16384!8i8192

[baugh17]

Does anyone know of any HAWK signals erected by New York State DOT, especially on Long Island? I haven't seen any yet and I'm wondering if NYSDOT is embracing this concept with the same zeal as flashing yellow arrows which they're putting up all over the place.

My native Nassau County DPW so far has not put up any HAWK's that I know of, and so far they don't seem to be using FYA's either. They stick to the KISS principle, (Keep It Simple Stupid) which I kind of agree with.

There's probably one somewhere.

You will not see new HAWKs in Region 3 (Central NY).  Region 3 has determined other safety measures are more effective, per my understanding.

I am a big fan of FYAs.

I think the general public has adapted to FYAs because of their widespread use.  But I digress.

The only HAWKs I know of in New York are in the Buffalo area.  There are maybe a half dozen including a NYSDOT install on NY 324 in Amherst (http://newyorkroutes.net/images/photos/routes/324/324-10.jpg).

Then you have these (http://newyorkroutes.net/images/misc/watkins.JPG) which I'm guessing is more of a beacon.  I know of two...this one in Watkins Glen and another in Malone.

Does R3 share the same general sentiment as the rest of the state?

[Rothman]

Does anyone know of any HAWK signals erected by New York State DOT, especially on Long Island? I haven't seen any yet and I'm wondering if NYSDOT is embracing this concept with the same zeal as flashing yellow arrows which they're putting up all over the place.

My native Nassau County DPW so far has not put up any HAWK's that I know of, and so far they don't seem to be using FYA's either. They stick to the KISS principle, (Keep It Simple Stupid) which I kind of agree with.

There's probably one somewhere.

You will not see new HAWKs in Region 3 (Central NY).  Region 3 has determined other safety measures are more effective, per my understanding.

I am a big fan of FYAs.

I think the general public has adapted to FYAs because of their widespread use.  But I digress.

The only HAWKs I know of in New York are in the Buffalo area.  There are maybe a half dozen including a NYSDOT install on NY 324 in Amherst (http://newyorkroutes.net/images/photos/routes/324/324-10.jpg).

Then you have these (http://newyorkroutes.net/images/misc/watkins.JPG) which I'm guessing is more of a beacon.  I know of two...this one in Watkins Glen and another in Malone.

Does R3 share the same general sentiment as the rest of the state?

I don't know about other Regions' stances on HAWKs.

[Scott5114]

Oh wait, these aren't traffic control signals as defined in the Manual. They are Beacons which are a different set of rules.

Yeah right; like the average driver knows the technical difference......

This is further reason that they should only be used mid-block, but drivers encounter dark beacons away from intersections all the time.  Think of a stoplight warning sign with an attached double yellow beacon:  some of them remain dark until the light is about to change.

Kphoger, the difference is that the stoplight warning beacon is just an advisory/caution beacon. Whereas the HAWK is a regulatory signal just like a normal traffic light, so in my opinion the FHWA shouldn't be calling it a beacon. They define it as a beacon because it doesn't meet their definition of a traffic control signal which operates continuously alternating the right-of-way between at least two approaches.

And again if the Feds think the average driver is going to make that distinction between different types of traffic lights, well good friggin' luck. It'll be interesting to see how many drivers stop at dark HAWK signals at night thinking it's a defective traffic light that's completely out.

Nobody expects the general public to care about the beacon/signal thing. The HAWK was intentionally designed to fall under "beacon" rules because if it fell under "signal" rules it would be subject to signal warrant requirements. Those warrant requirements are, I believe, precisely why a lot of cities couldn't install standard R-Y-G ped signals before the HAWK was invented (around here, the only places I've seen them are immediately adjacent to schools).

I'm guessing either Los Angeles doesn't care about the signal warrants because they have the political clout to not particularly care what FHWA/NCUTCD wants, authority granted by the state of California or the California MUTCD to ignore the federal signal warrants, or enough traffic to more consistently meet the signal warrants than other cities do.

Obviously the real solution is to correct the signal warrants to make R-Y-G signals for pedestrians easier to legally install, but hell, we're, what, a year overdue as it is for MUTCD 11e now?

[SignBridge]

Scott5114, the reason I bring up the issue of the public not understanding beacon vs. traffic control signal is because different driver conduct is expected when approaching a dark signal depending on the type.

Drivers are expected to treat a malfunctioning dark traffic signal like a stop sign. But they are permitted to drive thru a dark HAWK. So if they don't know the difference between the two types, how will they know what to do when they approach a dark HAWK signal. They may stop thinking it's a defective traffic control signal and maybe get rear ended for trying to do the right thing.

[Hobart]

Oh wait, these aren't traffic control signals as defined in the Manual. They are Beacons which are a different set of rules.

Yeah right; like the average driver knows the technical difference......

This is further reason that they should only be used mid-block, but drivers encounter dark beacons away from intersections all the time.  Think of a stoplight warning sign with an attached double yellow beacon:  some of them remain dark until the light is about to change.

Kphoger, the difference is that the stoplight warning beacon is just an advisory/caution beacon. Whereas the HAWK is a regulatory signal just like a normal traffic light, so in my opinion the FHWA shouldn't be calling it a beacon. They define it as a beacon because it doesn't meet their definition of a traffic control signal which operates continuously alternating the right-of-way between at least two approaches.

And again if the Feds think the average driver is going to make that distinction between different types of traffic lights, well good friggin' luck. It'll be interesting to see how many drivers stop at dark HAWK signals at night thinking it's a defective traffic light that's completely out.

Nobody expects the general public to care about the beacon/signal thing. The HAWK was intentionally designed to fall under "beacon" rules because if it fell under "signal" rules it would be subject to signal warrant requirements. Those warrant requirements are, I believe, precisely why a lot of cities couldn't install standard R-Y-G ped signals before the HAWK was invented (around here, the only places I've seen them are immediately adjacent to schools).

I'm guessing either Los Angeles doesn't care about the signal warrants because they have the political clout to not particularly care what FHWA/NCUTCD wants, authority granted by the state of California or the California MUTCD to ignore the federal signal warrants, or enough traffic to more consistently meet the signal warrants than other cities do.

Obviously the real solution is to correct the signal warrants to make R-Y-G signals for pedestrians easier to legally install, but hell, we're, what, a year overdue as it is for MUTCD 11e now?

Wouldn't it have been a lot easier to just add a line to the 2009 MUTCD that made HAWK-eligible crosswalks warrant a traffic signal? That's always what's bothered me about them.

[kphoger]

They may stop thinking it's a defective traffic control signal and maybe get rear ended for trying to do the right thing.

Has this actually happened, anywhere, ever?  Or are you inventing a hypothetical problem that doesn't really exist?

Rear-end crashes happen all over the place, of course, and HAWK locations are no exception.  But are you aware of any rear-end crash at a HAWK crossing that was due to the specific reason you stated?  Even if such has happened, the benefits provided by having the signal dark until activation may outweigh that.

Meanwhile, the FHWA asserts:

Pedestrian Hybrid Beacon Guide – Recommendations and Case Study

Because PHBs remain dark until activated, they can help increase driver attention to pedestrians crossing the roadway, and can reduce rear-end collisions. The pedestrian hybrid beacon's red signal indication removes any judgment from the motorists and requires a complete stop.

A preliminary report from back when HAWKs were introduced in Phoenix indeed showed a reduction in the total number of rear-end crashes and basically no change in the total percentage.  Details are shown below:

Safety Effectiveness of the HAWK Pedestrian Crossing Treatment – July 2010

Rear-end is the most common crash type for all types of intersection control, representing between 40 and 60 percent of the crashes for a given type of traffic control at the intersection. After rear-end, the most common crash types were left-turn and angle.

The dataset shows rear-end as the most common manner of collision for the HAWK intersections in both the before and after periods (illustrated in figure 7 and figure 8). The distribution of IR crashes at the HAWK sites before the HAWK was installed included rear-end (55 percent), angle (13 percent), left-turn (15 percent), and pedestrian (5 percent) crashes. After the installation, the greatest changes in the distribution of crash type were an increase in angle crashes to 19 percent and a decrease in pedestrian crashes to 1 percent.

[...]

A preliminary review of crash type at the HAWK sites indicated a reduction in rear-end crashes, which is not typical when a higher level of control is implemented at an intersection. A potential reason for the reduction in rear-end crashes is that drivers behind the initial vehicle that has stopped for a crossing pedestrian can view the traffic control device without needing to see the pedestrian, who may be obscured by the lead vehicle. Additional research to investigate the changes in crash patterns at the HAWK sites should be considered.

https://www.fhwa.dot.gov/publications/research/safety/10042/10042.pdf

[jakeroot]

They may stop thinking it's a defective traffic control signal and maybe get rear ended for trying to do the right thing.

Has this actually happened, anywhere, ever?  Or are you inventing a hypothetical problem that doesn't really exist?

I'm personally sold on the opposite problem: virtually no one stops at dark HAWK signals (because they shouldn't). This is good, of course, as they shouldn't. But is it potentially training drivers that not all dark signals require a stop? And when I say "signals", I mean things that are overhead or on the edge, and that light up with colors to indicate what to do...I assume that's how most drivers interpret it, anyways.

[kphoger]

I'm personally sold on the opposite problem: virtually no one stops at dark HAWK signals (because they shouldn't). This is good, of course, as they shouldn't. But is it potentially training drivers that not all dark signals require a stop? And when I say "signals", I mean things that are overhead or on the edge, and that light up with colors to indicate what to do...I assume that's how most drivers interpret it, anyways.

I don't like the dark signal rule anyway.

For example, if a new signal is going in, most agencies either turn the signals away from the road or put bags over the signals.  However, if I'm driving at 55 mph after dark, then it is not apparent if the signal is turned, bagged, or simply not functioning.  (And yes, this came up for me.  There's a specific signal I'm thinking of in my area that was recently installed along a 55mph stretch of road, and I couldn't tell until I was practically right under it.)