Call board safety video

From the “I forgot I had this” files (sometimes I have the memory of a goldfish). This is a short TriMet safety video about call boards and their use to protect workers in the right of way. Safety at rail is not a joke and it’s never taken lightly because of how severe the consequences of a lapse in safety can be. I think it’s a good thing for the public to see things like this because ordinarily they don’t get the opportunity to watch how much effort goes on “behind the scenes” to keep things running smoothly and safely.

Not your normal operating conditions

To date, most of what I’ve written about has been how things work under normal operating conditions because, well, that covers most of what people ask about since it’s what you encounter on a day-to-day basis (how fast do the trains go, what kind of signals do they use downtown, etc). But there are a lot of interesting things that go on outside of normal operations (e.g. manual blocks), and if you were riding the trains through the recent weekend maintenance work between Sunset and BTC or on the Yellow Line, you would’ve seen some unusual moves, wayside flags, and signal aspects.

For reference, these are wayside flags (here stored at the Elmonica yard)

If you missed it, it’s okay, other people went out and took pictures and are letting me use them, so thanks to them I’ve got some content for this post.

First off -

What was the maintenance work for, anyway?

As you may recall (and now that we’re heading into June, I expect this old entry to start getting more traffic if/when we get a heat wave), extreme heat conditions can adversely affect rail. In areas at risk for sun kink, which is a lateral slide in the rail caused by the rail buckling as it expands in the heat, slow orders (reductions in speed over a specified area) are issued.

10mph slow order in between BTC and Sunset

The expansion joints prevent this buckling by having gaps in the rail that give room for the rail to expand, thus absorbing the stress and force of the heat expansion. In order to put these expansion joints in, parts of the alignment had to be shut down.

So what does that involve?

Out of service, Yellow Line

When a track is out of service, double red wayside flags will be used – one in between the rails, one immediately next to them (also seen at Sunset on Pdxrailtransit’s blog). You do not proceed past double red flags for any reason.

Yellow/Red Wayside Flags

Double red flags will be preceded by yellow and red wayside flags like these. These indicate that a train will have to stop within 1000 feet. Here on Interstate, these were placed before the southbound platform at Lombard because trains were using the switches just north of the northbound platform to turn back.

Turnbacks

This train has already turned back and is now heading south on Interstate. Those of you with sharp eyes may have noticed a familiar signal in the last two pictures, with an unfamiliar aspect:

Yellow X on summary switch indicator 427

Time lock switch refresher time! These summary switch indicators on Interstate inform operators of the state of the time lock switches. Under normal operating conditions, these display a lunar which tells operators that the switches are aligned normal and are locked. Once the padlock for the switch has been removed, the summary switch indicator will display a yellow X, as shown above. For this work, operators stopped trains just past the 427 A and 427B switches, went back to what had been the trailing cab of their train, and crossed over to the southbound track to continue service southbound. Because the padlocks were off so that supervisors could throw the switches to enable trains to make this move, this summary switch indicator for the 427 switches displayed a yellow X.

Time lock switches were also used on the west side for turnbacks, as shown here at Beaverton Transit Center (also at Sunset for trains to go back east – sorry, no pics of those):

This series of pictures shows an eastbound train approaching BTC via the pocket track, which is normally the end of the line for westbound Red Line trains. This train is going to head west from BTC out of this same track, this time switching over to the westbound main. If you’re not very familiar with the layout here, it may help to see the overhead view – even though it takes a while to get a train through time lock switches, there’s not really any alternative to doing turnbacks from this side, and the time lock switches are still much faster than requiring trains to run reverse (which would involve restricted speed, no signal protection, use of island circuits to cross gated intersections, etc).

Similar to the first picture of the double red flags on the Yellow Line where you can see supervisors ready to throw the switches once the timer counts down, Pdxrailtransit got some pictures of supervisors at BTC who were on hand to throw these switches – remember that time lock switches are manual switches, not power switches, so they can’t be thrown from the cab of the train. Someone on the ground needs to manually throw the switch, and while operators can do it when necessary, it’s faster to have someone else taking care of it in planned situations like these.

So sure, some passengers were not happy with the additional travel delays, but for the people who like seeing some of the more unusual operations of the system, there were some nice examples of that over the last few weeks. Silver lining, right? And the expansion joints will make those areas safer in hot weather, so really this benefits everyone.

Types of track layouts

Know your pockets from your tails.

This post stems from some conversations I’ve had with readers lately about what a pocket track refers to, or where and what the auxiliary track at Gateway is. This is more of an alignment design topic, rather than a discussion of the physical differences between types of rail.

Pocket tracks are those sandwiched between mainline tracks, some of which are used more frequently than others. For example, Red Line trains always pass through the pocket track at Gateway to go west, and they end in the pocket track in Beaverton Transit Center, but the pocket track near Hollywood (linked photo not mine) is mainly going to be used for something like getting a disabled train out of the way and not as part of normal service.

Pocket track by the Fair Complex

Red Line in BTC pocket track

Pocket tracks are also found near the West Portal of the tunnel, near the airport,  and by SE Main Street.

A siding is a track diverged off to the side of the mainline that can be used for turnbacks or temporary storage.

Doubletree Siding with an out of service train- this siding had also been used by the Vintage Trolley

Another siding under the Broadway Bridge (linked picture is not one of mine) has been used for tripper trains. For example, some rush hour service trains that start from Hillsboro would go just past Interstate Rose Quarter, and then pull into the siding to swap cabs and go back west.

A tail track is a track just beyond the end of the line that can be used for storing a train.

Looking toward one of  the tail tracks at Cleveland Avenue

There are also several auxiliary tracks at different locations, such as Hatfield, Expo Center, and Gateway. The ones at Hatfield and Expo are functionally very similar: a third track diverging at the end of the line.

Borrowed picture of the auxiliary track (the snow-covered one with no train in it) at Hatfield a few years ago.

Gateway is actually pretty complex, so here’s a picture*, complete with my excellent MS Paint skills.

(like all pictures, click for larger version)

Okay, so this is not quite oriented the correct way, but it’s close (for a correct view without the color designations over it, go here). The platforms are the area near the upper left corner of the picture – Blue, Red, and Green Lines using the eastbound mainline (the bottom track that has all three colors on it), Blue and Green using the westbound, and Red using the pocket track to go west.

The most identifiable feature is the Red Line’s “fishhook” – a stretch of single track that connects the I-205 north alignment with  Gateway. A Red Line will diverge onto the fishhook to go to the airport, and will also come back up the fishhook to go into the pocket track, which is the only track they can access to go west. There’s no way for a Red Line to go directly from the fishhook into the westbound mainline – only Green and Blue Lines will use the westbound main at Gateway.

Notice how there’s a short section of the “eastbound” track that will actually be used by Red Line trains in both directions. This is why you might occasionally be sitting on an eastbound train at Gateway for a while – an incoming Red Line could have locked you out until it gets into the pocket track.

Then there is the one part of the track that doesn’t have a colored line over it, diverging off the pocket track and running between the east and westbound tracks out the bottom right side of the picture – this is Gateway’s auxiliary track.

The Gateway auxiliary track is never used in service to let passengers off the train since there’s no platform there. If an eastbound train needs to be moved into the auxiliary track to be stored, all passengers will exit the train in the Gateway pocket track before the train is moved there.

*This picture is accurate for most trains. Green Lines going from Clackamas to the Ruby yard or from Ruby to Clackamas will use the auxiliary track to get into the pocket to swap cabs and change direction; some Red Lines become Blue at Gateway so it’ll be a Blue coming up the fishhook into the pocket track; if there’s a disabled train in one of the tracks then the pocket can be accessed from either side to get around the broken train, etc, but for most of the service day this is essentially how it works.

Special events tracks - these are found at PGE Park westbound and Rose Quarter (which has the same kind of layout as a pocket track, though the westbound track is not pictured in the linked photo). As the name suggests, these tracks and associated platforms are used for increased service during special events in these locations.

Special Events track at PGE Park

There are also two stub tracks at the north end of the transit mall by Union Station that can be used to store a train. Even though a single-car train is pictured below, both have room to store a two-car train.

North Mall East Stub

To summarize, all of these different types of track layouts increase the flexibility of a rail system by permitting several kinds of train movements and (when necessary) enabling malfunctioning trains to either be temporarily stored out of the way or giving other trains a route to get around them.

System change

These have been around lately on the east side, due to the platform work done at Civic Drive and Rockwood. Pretty self-explanatory – they are a reminder that something fairly significant has changed in the alignment ahead, such as the opening of a new platform or changes to signals, so you can’t proceed through this area the way you have been accustomed to. Civic Drive, for example, is now an active platform instead of a closed platform that gets bypassed at 20mph, and Rockwood has a temporary platform and a slow order going through there, so the system change signs are a cautionary reminder of this work.

Guard rails

Question: What are the extra rails for?

Extra rails between the rails

EMS has already done this one, but I don’t remember where that post was – if I can find it I’ll add a link.

Passengers looking out the window will sometimes notice (especially along the Banfield) what looks like extra rail laying in the track. It looks a bit haphazardly placed along the Banfield so it’s not as obvious what it’s for as it is when you see it placed symmetrically, like in the above picture which is the overpass just east of Sunset TC.

These guard rails are placed as added protection in case of derailment in high speed areas. Granted, derailment isn’t good under any circumstances, but there are some areas where a derailed train would be more catastrophic than others. So you’ll see guard rails wherever trains go over an overpass, like above..

82nd Ave looking west

…or under them, like here at the NE 82nd Avenue platform. In both cases, derailments would be extremely dangerous and could potentially cause serious structural damage to the overpass – to say nothing of the damage to the people inside the train – so the extra rails are placed as added protection should the wheels leave the rails they’re supposed to be on. Derailment along flat terrain is obviously not ideal, but a train derailing into or off of a bridge is far worse.

Or doing this…

Looking out the trailing cab of an eastbound train at Beaverton Central

You can also see those extra rails placed around curves, like in this picture looking west from Beaverton Central, or like this picture I’ve already posted looking east at Gateway. All of these examples are in t-rail, not girder rail.

2008 derailment downtown, SW Morrison & 11th

Trains can still derail in girder rail, but guard rails aren’t used in that type of rail – I think both the physical structure of girder rail and the low speeds that trains travel through areas with girder rail wouldn’t benefit from adding in guard rails.