The NS Bridge Line PTC Adventure

For years concerns of PTC interoperability drove all manner of decision making at freight and passenger railroads. For example's CSX decision to isolate itself from SEPTA's Regional Rail network, NICTD choosing not using the cab signal codes present on its line because Metra Electric wanted to use the freight-centric ETMS and MARC dumping ACSES for reasons. However one common thread is that when push comes to shove, equipping locomotives with multiple PTC systems is not a big deal (although it certainly isn't free).

Case in point are the SD60E locomotives that are always leading certain Norfolk Southern intermodal and manifest trains traveling on its New England Bridge Route between Harrisburg and Ayer, Mass. Between Harrisburg and Sunbury its on ETMS, then its off PTC entirely all the way to Binghamton. Then it on CP's ETMS all the way to Mechanicville, NY. From there it hits the former Boston and Main which is again PTC-less, but at Wachussetts it enters MBTA territory which uses Rule 562 cab signals and ACSES the last few miles to Ayer. These SD60E's are dual equipped for PTC and ACSES and although less needed on the NEC due to Amtrak dual-installing ETMS, they found a new home on this run. If I ever get close to one I'll see if I can get a photo of the antenna. 

Anyway, I heard that due to the shift of NS New Englande route internodal trains to the former Conrail Boston Line, this unique PTC situation will soon be obsolete as manifest freight might terminate at East Deerfield or something. If you're a fan of oddball leading equipment quirks, get your photos while you can.

Velcorp Gems - A New Signal Supplier Enters the Fray

While out riding the new MBTA Green Line Extension I noticed a new corporate brand stenciled onto the back of a cheap looking transit type LED signal head.

My original assessment that  Velcorp is the company and GEMS is the brand name of their rail signaling equipment turned out to be incorrect as Velcorp was actually Virginia Electronic & Lighting LLC and GEMS was their subsidiary General Electronics Mechanical Services, which I guess does all the rail stuff? Anyway, as you can see below the product looks to be on the low end of the build quality scale with exposed nuts on the front, lots of hard angles and what appears to be a non-locking access door on the rear.

 

The mounting equipment is branded as Harmon, which may be doing business under the Landsay brand now. Each signal also has a pair of mounting brackets on the top that look a bit like owl tufts. From Velcorp's website it looked like they had previously focused on LED modules before suddenly getting the contract for the GLX wayside signals. Velcorp isn't local so maybe its a Veteran owned small business or something.

Despite their appearance, the signals seemed to work well enough. Still, I have not encountered them on any other transit system. Velcorp is one of several entrants into the rail signal space to have offered up products competing against the legacy brands of US&S and GRS (Alstom) who have the capability to make larger cast aluminum and iron housings.

MBTA Re-Signaling Project Reaches Lowell

An update for my previous reports on MBTA's re-signaling efforts on Boston's north side commuter lines.This project consists of installing cab signals and Rule 562 operation on all or part of the North Side lines as well as the general replacement of GRS SA-type searchlight signals. In fall of 2020 the project had already commenced, but there was no sign of it at CPF-BY in Lowell when I stopped by for a visit. 

In fact I even documented ongoing maintenance work on what appeared to be brand new replacement SA heads.

Well recent photos indicate that the re-signaling work has no only reached CPF-BY, but also also replaced the GRA SA searchlight dwarfs with L&W LED searchlight dwarfs, which I guess is better than Safetran cube stacks.

At this point there is no information about CPF-LO, CPF-WA and CPF-NC located beyond the end of MBTA operations at Lowell, but before the end of MBTA ownership at CPF-NC. I suspect this might become a signaling sanctuary as CSX would want to avoid needing to run cab signal or ACSES equipped leaders here and the MBTA would want to hold out for Federal rebuild money to extend service to Nashua.

CPF-NC in late 2021 showing no signs of change.

Additional reports indicate that CSX has dropped new signals at CPF-309 and/or CPF-307 which would be in line with their plans to assimilate the old Guilford territory.  No word if the new signals are CSX standard hoods or Guilford/MBTA targets and also if CSX is planning to run Rule 562 as all Boston Line locomotives will be cab signal equipped and multiple sections of the old Freight Main Line will have MBTA cab signals.

CSX Bags Guilford But When to Expect Change?

CSx is set to complete its purchase of the former Guilford Rail System (currently branded pan Am Railways) on June 1, 2022.  However does this mean to immediately expect the end of NORAC Rules, searchlight signals and bracket masts? Well according to some initial reports the community will enjoy at least a slight reprieve before CSX has the opportunity to go to town on the Boston and Maine's legacy.

Guilford searchlights and the Lowell Wye.

As of now CSX plans to make no changes to former Guilford operations until October, 2022 due to the existing collective bargaining agreements and delays to the sale of the Pan Am Southern joint venture to a G&W subsidiary.  This means NORAC Rules and signal indications will remain in service until that point and it is unlikely that CSX will embark in any large scale re-signaling investments. CSX will also need to improve/signal the line between Worcester and Ayre to actually connect the former Guilford Freight main Line with its former Conrail Boston Line.

Boston Line CP-45 at Worcester

In the longer term, use of Rule 562 cab signal without fixed wayside signals on both the former MBTA territory as well as the Boston Line will likely keep the former Guilford territory under firmly under CSX's legacy "Conrail" signal rules, even if the operating rules change. How PTC is integrated into the new territory remains to be seen as MBTA lines that share the former Guilford Freight Main Line route around Lowell, Ayre and Haverhill, will be ACSES and cab signal equipped. It is entirely possible that CSX will choose to complete the look and install 562 between Worcester and Ayre and as part of any re-signaling projects on the Freight Main Line, including the Downeaster corridor north of Haverhill. 

Boston Line CP-187 with Conrail Small Target Searchlights

 As has been observed on the Boston Line, Darth Vader type signals have been slowly supplanting those of Conrail vintage, however this process is not complete after 20 years due to the young age of the vintage Conrail signaling. Fortunately the former Pan Am Southern covers both the Freight Main Line to Mechanicville, NY and the CT Valley Line used by Amtrak. The latter was recently re-signaled in the Guilford style with the remainder getting a mix of Darth Vaders and Guilford signals in any re-signaling projects.  I suspect the orphan nature of this route will further stunt investment, hopefully prolonging the life of the remaining B&M vintage searchlight equipment and US&S pulse code CTC .

MBTA Putting Cab Signals w/o Waysides on Guilford Main Line

 I had previously reported on the conversion of at least some North Side MBTA lines to a system of cab signals without wayside signals as part of the ACSES PTC project.  However for some time the Guilford Rail System had been resisting this as they were not required to install PTC and they did also not utilize cab signals on their system.  Therefore imagine my surprise when I discovered that the Guilford Freight Main Line between CPY-WF and the end of passenger service at Wachusett.  

 

Technically the portion west of CPF-AY in Ayer is part of the NS Pan Am Southern joint venture and with CSX still trying to purchase the Guilford, two cab signal users would dismember the Guilford and would have equipped locomotives available to lead on the freight main line.  Still, dealing with cab signal islands is a major headache and it is further puzzling that waysideless cab signals (NORAC Rule 562) would be the preferred method between the back-to-back  CPF-AY and CPF-WF where the MBTA trains exit towards Boston.  Perhaps the plan is to be able to dive NORAC Rule 280a, Clear to Next Interlocking, bor unequipped movements. 

 

Regardless, we have seen with SEPTA that it seems easier to equip two types of PTC systems than mixing trains equipped and unequipped with cab signals.  CSX literally SEPTA-rated itself from SEPTA to avoid a situation similar to what the Guilford is acquiescing to. The good news is that Guilford style signals including target heads and bracket masts are being used in this project.  Unfortunately it is likely that fairly new Guilford intermediates with offset heads and double green clear indications may be removed prematurely. 

In an interesting turn of events, Guilford or the MBTA have decided to spring for genuine US&S NR-1 target type signal heads instead of an off brand modular approach. No way CSX or any other potential owner would do such a thing.

Cab Signals Come to Boston's North Side

Well the mystery is over, it appears that at least some of the North Side MBTA lines (former Boston and Main) are not only getting the ACSES PTC system, but also the Rule 562 cab signaling arrangement that also comes with it.  Moreover it is triggering the replacement of searchlight signals that were considered safe only a year ago like those that used to be at WINCHESTER interlocking on the New Hampshire Route Main Line.  

At this point the cab signals are in service between some point north of North Station (likely SOMMERVILLE interlocking) and WINCHESTER interlocking in Winchester, MA.  While the MBTA has actually fitted some of its searchlights with 562 'C' boards, the ones in Winchester got the LED tri-light treatment. While this line segment had been recently re-signaled, the section between WINCHESTER and the Anderson Regional Transportation Center featured at least two locations with bi-directional, twin head searchlight masts that would display the rare Double Green Clear signal aspect. 

 The spread of Rule 562 across the MTBA North Side could mean the extinction of this once popular signal aspect.  The good news is that the joint Guilford freight trackage should preserve some populations of wayside intermediate signals and the MBTA has shown a willingness to preserve some legacy searchlights.  Fingers crossed.  I will hopefully be able to get up to the Boston area in the March 2021 time frame to document whatever remains.

MBTA Installing New Searchlights in Lowell

I know this is the third MBTA post in a row, but I was preparing for a trip there, which led to some discoveries, and then actually went on a trip there, which lead to further discoveries.  In this instance the news is wholly positive as when I was taking a little walk around CPF-BY south of the Lowell MBTA station I noticed that MBTA signal crews were in the process of installing new replacement GRS SA searchlight signals.

Here on this dwarf signal you can see the brand new mounting hardware, base and signal cable.  However I know this is rather weak evidence of the "newness" of searchlights, but I actually showed up when the signal crews were part way done installing the refurbished searchlight dwarfs.

Hey, break time is break time, even if you're only half way through your work task.  They literally dropped what they were doing leaving the searchlight signal housing wide open.  If you look at the full resolution you can see a 1980's style GRS identification plate.

Anyway, I hope to get back to the Lowell area soon.  Lots of interesting signaling there that appears ready to stick it out in the long term.

MBTA Cab Signal Project to Include All South side Lines

I previously reported on the Rule 562 cab signaling project on the Boston Line that extended the cab signaling from CP-21 in Framingham to the Amtrak division post at COVE.  It now appears that the need to install cab signaling for the ACSES PTC system is resulting in the same treatment being given to the Needham and Franklin Lines.

NEED Interlocking eastbound mast.

As we saw with the Boston Line, existing interlockings are being left unaltered, except for the addition of Rule 280a "Clear to Next Interlocking" lamps, as seen here at NEED interlocking on the Needham Branch during the summer of 2019.

New Franklin Line interlocking in Norfolk, MA

 An exception to this is on the Franklin Branch where several additional miles of double track are being added with the eventual goal of the double track extending all the way to Franklin/Dean College.  This is resulting in new interlockings with new cantilevers and new Safetran scallop shells arranged in a target formation.

Franklin Line Signal 284.

Most of the signals appear to be legitimate GRS G-Head signals, installed in the 1980's to replace the original New Haven signaling although the Franklin Branch will also be losing searchlight intermediates at mileposts 11.7 and 13.1.  Additional color light signal locations presumably being lost are mileposts 16.9, 22.1, 23.5, 25.9 and 28.4 on the Franklin Branch and mileposts 7.1, 9.6 and 10.6 on the Needham Branch.

Franklin Line signal 302

Uncertain are the 12.6 and 12.7 automatics around Needham Center and the 302 automatic at the Forge Park/495 Franklin Branch station where terminal operations make wayside signals somewhat useful.  As of Aug 2019, the holdout signal at CP-HEIGHTS on the Needham Branch did not have a 'C' board mounted.

Stoughton Branch CP-PORTER

Needless to say this should not have come as any surprise.  Not only were all three of the 90's/2000's Old Colony Lines built with complete Rule 562 signaling, but the short Stoughton Branch off the Amtrak Main Line at Canton Junction was 562 as well.  Moreover, the Dorchester Branch, cab signaled in the 80's during its time as Amtrak's route into Boston during the Southwest Corridor rebuild, lost its famous rectangular signals during a late ~2000 562 re-signaling project.  Ironically, this leaves Amtrak's Shore Line, the one with 150mph speeds and ACSES installed since 2000, as the only south side MBTA route to retain its intermediate signals.

Former Conrail Boston Line Completes Cab Signal Conversion

Sometime over the winter of 2019/20 the MBTA cut in the last section of Rule 562 cab signal without fixed wayside signal territory on the former Conrail Boston Line between the Amtrak division post at COVE and CP-21 in Framingham.  This completes the cab signal conversion project that was imitated by Conrail in 1988 and carried out in three distinct phases over the following 32 years.

Rule 280a 'C' boards are up at CP-3 (Photo Credit Fred G.)

In 1988 the Conrail Boston Line, originally built as the NY Central affiliated Boston and Albany (B&A), was showing its age.  The two track, Rule 251 ABS signaled line was an expensive albatross in post-industrial New Englande. Seizing the opportunity, Conrail decided to rebuild the line and in the process set a new standard that continues on to this day, most notably under under NS.  At the time the state of the art for a Rule 251 ABS conversion was a mix of CTC and single tracking.  Conrail decided to take this one step further and installed cab signaling without fixed wayside signals to compliment the adoption of CTC and single tracking on most of the B&A's 200 mile long main line. 

CP-147 with Conrail standard target signals and legacy SA searchlights now serving as Clear to Next Interlocking lamps.

The first part of this rebuild stretched from CP-187 at the Post Road Branch junction to CP-33, midway between Framingham and Worcester.  While this system had been tested on the PRR's Conemaugh Line in 1948, the Boston Line project would mark the first use of cab signal only operation by a post-deregulation freight railroad.  More surprising is how the former B&A was well away from Conrail's existing cab signal territory on former PRR routes and signaled a commitment. by Conrail, to deploy cab signaling as standard equipment on its full fleet of road freights.  Conrail would later repeat the cab signal rebuild process on the Morrisville, Fort Wayne and Cleveland lines before the 1999 sale and breakup halted further expansion of cab signal territory. The project also involved the use of color tri-light signals, a departure from the small target Michigan Central style searchlights Conrail had briefly favored during the 1980's.  The color tri-lights would remain Conrail's default signal up to the 1999 sale and beyond via the Shares Assets Operations. 

Clear to Next Interlocking lamps at CP-21 turned to await a cab signal extension that would take 22 years to complete.

Halting the cab signals at CP-33 in 1988 allowed the MBTA commuter operation that ran between Boston South Station and Framingham to avoid having to cab signal equip whichever trainsets that on the line.  Conrail did eliminate the remaining single direction ABS between CP-33 and COVE and also preserved the line as fully double track.  Nine years later, the MBTA was expanding and the Rule 562 cab signal equipped Old Colony lines would generally eliminate the desirability for non-cab signal equipped trainsets running out of South Station.   In 1996 the second track was restored between CP-33 and CP-43 east of Worcester with the decision being made to extend the cab signals through to CP-21 Framingham.  While 'C' lamps were installed on the eastbound masts at CP-21, they were turned out of service as the recently upgraded CTC signaling between there and COVE was seen as not worth replacing.

New signals at the new CP-6

 In 1999 CSX purchased 48% of Conrail including the Boston Line, which quickly became an operational headache as CSX did not otherwise employ cab signaling except for the former Richmond, Fredericksburg and Potomac.  As CSX owned the line all the way to the Amtrak division post at COVE in order to serve the Beacon Park yard and intermodal terminal and has little interest in commuter operations, service on the MBTA Framingham/Worcester Line began to suffer.  In 2011 the state on Massachusetts offered to purchase the line and yard real estate east of CP-45 in exchange for land in Worcester for a new CSX intermodal facility.  This would allow the MBTA to improve both service and the physical plant with the first major project being the elimination of a single track bottleneck that existed between CP-3 and CP-4 to support the former yard.  By 2017 this project grew to encompass a new full crossover interlocking (CP-6) and, the extension of the Rule 562 cab signaling all the way to COVE.

Milepost 6 intermediate signals..

Milepost 7 intermediate signals.

Milepost 8 intermediate signals.

Milepost 10 intermediate signals.

 This unfortunately has meant the elimination of 4, bi-directional searchlight automatic signal locations.  Each of these 16 signals were equipped with two heads per mast to support a 4 block signaling arrangement that was necessitated by the short, 1.4 mile signal blocks between CP-11 and COVE.

God Bless the Guilford - Part 2

Back in Part 1 I used the example of the new Wachusett MBTA station to highlight how the Guilford Rail System was bucking the trend of sterile Darth Vader signals with not only a commitment to target style tri-lights, but also oddities like bracket masts and doll arms.  Well, a few additional examples from their Freight Main Line have tumbled my way.

First we have this new bracket mast near Cumbermand Center, Maine and not only is it a bracket mast, but it also shows us that the Guilford is still employing the antiquated Double Green Clear signal aspect from the old Boston and Main days!

Although unfortunately not target signals, the nearby CPF-185 is also sporting a new cantilever/bracket hybrid for movements off the Brunswick Branch (now used by Downeaster trains).

Speaking of the Downeaster, check out this new doll arm equipped bracket mast protecting a crossover just east of the Lawrence Station on the MBTA Haverhill line.  Not exactly a Guilford  purchase, but don't think that they probably don't have at least a little input.

Well that's it for now.  Hopefully we will see more wacky stuff like this in the future, as opposed to NS style Darths and cantilevers.

CBTC is a Scam and the MBTA Backs Me Up

Communications Based Train Control promises higher capacity at lower costs thanks to the magic of WIRELESS TECHNOLOGY!  However almost every real world situation that makes use of it seems to wind up costing a ridiculous amount, having major reliability problems or both.  It turns out that with signaling there is no free lunch, but when faced with overcrowded subway trains, planners can't help but get seduced by those lovely braking curved.  I mean fixed block, that's so 1890, surely we can do better!

In 2016 the MBTA was conducting a capacity study for the Red Line, which currently has a somewhat anemic throughput of 13tph in the peak period.  With new rolling stock on order, the (T) would literally have more cars than it could run.  The current signaling system made use of fix block audio frequency cab signals installed in the 1980's.  This is similar to many other transit systems such as the CTA, WMATA and BART.  Of course CTBC is the to go technology for capacity expansion and the study quickly confirmed this.  Oh wait, it didn't.

• A detailed analysis assuming a moving
block CBTC system on the Red Line was completed.

• Analysis found that a CBTC system would produce
an improvement of just one train per hour beyond
the improvement from the new cars and minor
system changes.

• Major Red Line capacity improvements can be
achieved without implementing very costly CBTC. 

• Long dwell times in the downtown area and close
spacing of stations limit CBTC as much as they
limit fixed block systems.

That's right, just like the costly NYC Subway L Train CBTC system only increased capacity by 2 trains per hour, applying CTBC to the Red Line would only improve capacity by 1 train per hour over a fixed block alternative.  Past a certain threshold capacity is limited by dwell time and the efficiency of terminal interlockings. The study also found...

• The shorter the block length, the closer the
system is to the ideal CBTC (moving block)
braking distance

• MBTA block lengths in the central subway already
average less than 500 feet (6 car trains are 416
feet long)

It's nice to see that for once a transit agency actually ran the numbers and decided that CBTC just wasn't worth it.  It turned out the best way to increase the capacity was simply to allow the new rolling stock to use updated braking curves that will result in later braking and more aggressive cab signal speed stepdowns.  Also the 1980's audio frequency cab signal system will have its components replaced with digital versions that have faster reaction time and thus allowances for less conservative block progression. 

Vanishing NEC Pneumatics (and other News)

The NEC continues to see a wide scale reduction in the number of pneumatic point machines. Within the last year BIDDLE and OAK interlockings on the southern end have been replaced by electric, BAY interlocking has been half replaced, LANDOVER interlocking is en-route to be decommissioned entirely and just recently FAIR interlocking in Trenton has started seen selective replacement of its still impressive pneumatic plant.

BIDDLE interlocking with new M3 point machines.

The HAROLD re-signaling project in support of East Side Access is not largely complete, however some track and switch work is ongoing for the physical connections to the new lines.

On the Shore Line a new interlocking, LIBERTY, has been commissioned west of the Kingston, RI station to support the new third track and island platform.

Around Boston, the ACSES PTC system is being installed on North Side MBTA lines, although it is not clear if this is in conjunction with cab signals or not. Normally ACSES is designed to work in conjunction with cab signals and ATC, but modifications to allow operation without cab signals is within the real of possibility.  Also notable is thatACSES transponders have not appeared in the Guilford Rail System territory, which is generally exempt from the PTC requirement and has demonstrated hostility towards installing it for the Amtrak service if not required to.

For some updates regarding recently reported stories, the Rule 562 'C' boards are up in both directions at OAK interlocking, although not in service and all of the PRR pedestal signals on the SEPTA trunk line between Suburban Station and 30th St station have been replaced by the new ersatz variety.

God Bless the Guilford

In this age of Darth Vader signals and shiny metal structures, it's nice to find a railroad that isn't afraid to stick with tradition, especially if tradition means thinking outside the box.  It wasn't long ago that signal departments would customize their hardware based on local circumstances or what they had sitting around the shop, as opposed to whatever some subcontractor is influenced to buy.  

Take the new interlocking at the west end of the new Wachusett MBTA station on the Guilford's Freight Main Line.  The eastbound mast signal has been installed across the opposite main line track requiring a doll arm.  If this isn't rare enough the Guilford decided to use a blue marker light instead of a blue reflector and even then they went with a GRS marker searchlight instead of something current.

If that wasn't odd enough look at the Westbound signal.  Instead of a cantilever or signal bridge the Guilford went with a three track bracket mast. I'm not sure I am aware of a similar structure in North America.  The rightmost signal is an automatic for the opposite main, the center the adjacent main and the leftmost, the station track.

Of course it doesn't stop with signals as one can see with the second hand standard cab GE's. :-)

Signs! Signs! Everywhere a Sign! - Eastern Passenger Roads

In Part 1 of my look at railroad station signs I covered the East Of Mississippi Class 1 freight railroads, NS, CSX, CP, etc.  Here in Part 2 I am going to be covering the passenger roads in the northeast, Amtrak, SEPTA, NJT, LIRR, Metro North, etc.  Surprisingly, as time has gone on the passenger roads have become significantly less labeled than their freight counterparts.  This could be due to cost cutting, a compact territory that makes getting lost less likely or simply a desire to hide operating practices from the general public. 

Amtrak operates its own trackage as part of the Northeast Corridor, Springfield Line, Harrisburg Line and, for a time, the Atlantic City Line.  Inheriting the infrastructure from bankrupt roads that would be later folded into Conrail, Amtrak would often just leave the old, typically Penn Central, sign in place.

The first thing Amtrak decided to properly brand were its manned interlocking towers where they

adopted a white on blue motif that would last through the present day. 

For remote interlockings constructed during the early NEC Improvement Project era, the Government dollars didn't really cover signs so Amtrak had to settle for stenciling on the relay hut.

The next standard that appeared around 1990 was a totally-not-Conrail white letters on blue background sign which also appeared on the Atlantic City and Springfield lines that were re-signaled at that time.

In the late 1990's Amtrak decided to add a touch of flare with a colorful sign that really showed off the old pointless arrow logo.  These appeared in just a few locations.

Meanwhile, further north Amtrak experimented with a white on black sign.  These are mostly seen on the Boston to New Haven segment and in northern New Jersey.

Which leads us to the present standard which I would call "low observable".  Not sure why Amtrak doesn't want to advertise it's interlocking names, but at least they kept the white on blue.

All Askew - Remaining Users of Offset Auto Signals

Back in the day, setting the heads of a multi-headed signal on opposite sides of the mast was an effective way as marking a signal as an automatic.  Although the presence of a number plate was an accepted and inexpensive way of doing the same thing, reflector technology wasn't as advanced as it is today.  Some railroads even went as far as placing markers on single headed automatics simply to make them more visually distinctive.

However as time went on this practice, like many, was seen as a luxury that did little for safety.  Since the 1980's most railroads have placed their signal head in line, regardless of automatic status.  However there are still a few that have stuck with the old ways.

Canadian National / Canadian Pacific

The CROR signal ruleset is perhaps the more strict when it comes to offset head placement as it is the only option to designate a signal as automatic as number plates can also appear on absolute signals (on absolute signals plates are used to denote the lever number).  On single head signals left hand placement is used to provide the distinction in addition to absolute signals always having two or more heads.

Unfortunately, as far as I can tell this policy does not apply to CN and CP's United States operations, although some vestiges exist like these somewhat modern unilens signals on the former D&H.

Flordia East Coast

Regional operators often become museums of signaling practice and in this regard the FEC has preserved the practice of offset head placement.  The FEC also uses a robust cab signaling system so this is even more interesting single they could probably eliminate waysides entirely if they wanted to.

Former Boston and Maine (Guilford Rail System / MBTA)

Public transport agencies are another place where traditional signaling practices can live on and combined with a regional freight operator we have the former Boston and Main system as our final holdout on the use of offset signal heads. Some of the newer heads are a bit less offset than others, but it's clearly still a thing.

Well that's all the ones I am aware of at this point.  There are probably others (I'm omitting the Reading and Northern cause that's somewhat of a special case). Please let me know if you know of any that I have missed.