Category Archives: anatomy

Rock and rail

And now here’s an example of using the scanner for subjects other than fictional prostitute stings. By now you’ve probably heard about the incident a few weeks ago at about 5am when an eastbound train hit a large rock in the right of way near the Murray overpass between Beaverton Creek and Millikan Way.

I was asked on Twitter if this was something that the sweep train (the first trains through the alignment in the morning that run at a slower speed to check for debris, damage, etc) should have seen. However, the sweep train goes through there at about 3:30am, and four more trains follow it before the one that hit the rock, so it’s very unlikely that the rocks ended up there overnight and were somehow missed by five trains.

eastboundblueLooking east from the Murray overpass where this happened

Given the size of the rock (I think it took both the supervisor and the operator to get it out of the way) and my complete lack of detective abilities, I’m not sure if it was thrown from the overpass or whoever did it trespassed down in the ROW and left it there. Regardless, TriMet is looking for anyone who might have information and is offering a $1000 reward for information.

Coordination when things go wrong

When something goes wrong on a train, it can be very frustrating for passengers to not know what’s going on, why are we stopped, how long are any delays going to be, and so on. Generally speaking, operators are going to try to keep you as updated as possible because the last thing anyone wants to deal with on a stopped or broken down train is passengers redknobbing the doors and potentially getting hurt trying to leave! Unfortunately, sometimes the available information is limited and your operator doesn’t have any better idea than you do when things will be moving again.

Wait, let me say that one again: Unfortunately, sometimes the available information is limited and your operator doesn’t have any better idea than you do when things will be moving again.

Annnd, once more for luck: Unfortunately, sometimes the available information is limited and your operator doesn’t have any better idea than you do when things will be moving again.

Additionally, your operator isn’t just keeping all of the passengers informed, but he or she also has to communicate with Control, sometimes almost constant communication depending on the situation which means less time to convey information to the passengers. Consequently, it can seem like you’re sitting there wasting time while nothing is being done to fix the problem. This isn’t the case, it’s just that you’re most likely not going to be able to hear all of the coordination that’s done over the air to address the issue.

Because the rock incident happened very early in the morning, there wasn’t a lot of other traffic on the air and so the scanner got just about all of the related calls. I like this because it shows how the operator, supervisor, and controller worked together to get service going again with as little interruption as possible (also, no one was injured in this incident so I don’t think there is anything sensitive in any of the calls). Due to the relative simplicity of this event as compared to, say, the power issues from last week, the radio calls for this are pretty easy to follow along. If you’re interested in listening to how this played out but aren’t familiar with TriMet’s open air radio, you might find this radio refresher helpful – remember that when on the air, controllers don’t use an identifier, operators use the train number, and supervisors have four-digit call signs beginning with 95. In this incident, the train is 21, the supervisor is 9514 (both male voices), and the controller is the female voice.

Here are the highlights: The beginning of the incident is a little choppy (some problems with the radio where 21 couldn’t hear the controller), but the controller was able to understand that 21 hit an object in the ROW, so she called westside supervisor 9514, who is monitoring everything from Washington Park to Hatfield. 21 was able to get through with a description of what happened, and then relayed to the controller what problem indications he had in his cab (among them are friction brake faults – this will be important in a moment). Since this train was in service, the most ideal thing to do is to try to get it into Millikan Way where passengers can be safely offloaded if the train has to be taken out of service, and 9514 would meet up with 21 there to assist.

21’s follower, Train 22, is held at Willow Creek. This keeps the eastbound alignment from Millikan to Willow Creek clear, which would allow 21 to run reverse traffic (west in the eastbound alignment) if necessary back to the Elmonica yard. Meanwhile, 9514 meets up with 21 and sees a friction brake hangup in the A-truck of his lead car. For a quick refresher of what that means:

T3 & 1 brakes

These red lights on the outside of the train are located above each of the three wheel trucks (A and B at either end and C in the middle) in the Type 1s, 2s, and 3s. It’s a little different in the Type 4s, but I’m skipping that for now since this incident didn’t involve a 4. When illuminated, these tell you that the friction brake in that wheel truck is applied. You want this when the train is stopped, as in the above picture. You do NOT want this when you expect the train to be moving! So 9514 was able to see that the exterior brake indicator in the leading truck of the lead car was lit as the operator was trying to move the train into the platform, and he knew that this meant that friction brake was “hanging up”, or staying applied. The way to troubleshoot this is to pump off the hydraulic fluid from that brake and manually release it.

mru3MRU, Type 3

Each train car has an MRU, or “Manual Release Unit” where a friction brake can be pumped off. This is a fairly basic procedure that every operator learns how to do in training, but the standard procedure is for the controller to pull up a checklist to follow for consistency. After the train made it into the platform and passengers exited, 9514 was able to inspect the car for damage, including the leaking hydraulic fluid pictured above which explained the brake problem. If the only problem a train has is a hanging friction brake, it can continue in service with one brake pumped off, but you can’t do more than 30mph so it’s not really ideal. Any more than one brake pumped off and the whole train has to be taken out of service. In this situation, because the train had hit an unknown object and 9514 was still assessing damage, the train most likely wouldn’t remain in service even with the brake pumped off, but they needed to figure the best approach to getting it out of the way. The controller suggested that the best solution might be a dead car tow – that is, pump off all three of the friction brakes in the car and have it be pulled back into the yard by the other car.

9514 decided to begin pumping off the friction brake in the A-truck of the car – they’d have to do that anyway for a dead car tow, but it was possible that pumping off that one brake might be enough to get the train rolling. At this point in the radio calls, there is a lot of back and forth between the controller and 9514 as she read through the checklist and he carried out the procedures. After the brake was pumped off, 9514 confirmed that it was holding (i.e., it’s staying released), and the controller asked 21 to take a point of power from the eastbound cab. Although the train would be going back west to Elmonica, this is just a fast way to verify that the brake is no longer applied in that truck. She then told Train 1, the incoming westbound train at Beaverton Transit Center to hold there (remember that 22 has been holding back at Willow Creek, so this is leaving both the eastbound and westbound alignment clear from Willow Creek to BTC). 9514 said he’d ride back with 21 to see if he can find what had been hit.

runningreverseNot the train involved in this incident, but it’s a train running reverse – this one going east in the westbound at Willow Creek

Now 21 was running reverse back to Elmonica west in the eastbound alignment. If you want more info on what running reverse traffic means, I did a post on it a while ago, and other posts with related things you’ll hear if you’ve been playing the transmissions so far (such as needing to key-by a dwarf signal and running at restricted speed). 21 made a brief stop under the overpass to see what had been hit and try to clear it so that other trains could safely get through, and that’s when they found the rocks pictured above. They got them out of the way so that the westbound trains (Train 1 still holding at BTC) could get moving again. 21 then arrived at the yard limit and took the train into the yard so that normal train movement in both directions could resume. The whole thing took about half an hour from start to finish, though given the spacing between trains, it wasn’t a major impact to service.

But consider train 22 who was behind the incident train. They would’ve been around Fair Complex when this happened, and then holding at Willow Creek for about 15 minutes while all of this played out. If someone on 22 asked the operator when things would get moving again, there’s no easy answer to that – if you played through all the calls, you now have as much information as that operator did. There’s no secret operator-to-operator information service that gets additional information and a timeline out (though that would be cool). At best, the operator can explain the situation at a very un-detailed level because once you start getting into brake pump-offs and technical things, people’s eyes are going to glaze over. But if that procedure had failed or if there was serious damage to the train, or if 21 and 9514 couldn’t get the rocks out of the ROW, this would’ve taken longer, but there’s no way to know how things are going to go while the incident train’s operator, the supervisor, and the controller are working on it. So once again, unfortunately it’s very likely that your train’s operator isn’t going to have any better idea than you do of how long something will take to fix and get rolling again.

Overall I think this incident was a good example of what’s going on “behind the scenes” when something breaks down. Getting things moving as quickly as possible again is on the mind of everyone involved; no one’s doing this to get a kick out of passengers missing their (often infrequently) connecting buses (and on a self-interest side, no operator enjoys running late and losing part or all of a break due to delays!) There’s a lot of coordination between operators, supervisors, and controllers in every kind of service disruption, but unfortunately most of it is going to happen where passengers don’t see or hear it.

10 secrets, tips and tricks for cold-weather TriMet riders

type IV


Editor’s note:
 Guest post time again, this one via Michael Andersen of Portland Afoot, PDX’s 10-minute newsmagazine about buses, bikes & low-car life. It’s excerpted from the January 2012 cover story and republished here in case you missed it. For more stories like these or to get a one-time email notice when the newsmagazine for Portland transit riders will be available for free on mobile devices this spring, visit PortlandAfoot.org.

Rain? No sweat. But let’s confess: Portlanders don’t do cold well.

That’s why, last year, our 10-minute newsmagazine for transit riders put some of the smartest folks in town (including TriMet’s professional comfort geeks) in the hot seat and came away with a bunch of tips and secrets for doing winter better.

As a longtime MAXFAQs fan, I was proud to be asked to republish the transit-oriented ones here, and happy to help take the chill off the tail end of this winter. So read these, wipe that drippy nose and go catch some sun.

- Michael

Slim Jim stylus

slim jim color

Smartphone styluses start at $13, touchscreen-friendly gloves at $14. Beef jerky sticks, by contrast, are $1.30, and they work just as well when you want to check arrival times with gloves on. Try it.

In with the old

There’s an easy formula for temperature control on TriMet’s old high-floor Type 1 MAX cars, says TriMet rail equipment manager Mark Grove: “Stay away from the doors.”

Pressure heater

doors

MAX doors don’t actually matter nearly as much as they might. Here’s why: TriMet keeps air pressure inside its trains just a bit higher than Portland’s natural atmospheric PSI. That means opening doors send a burst of controlled air out – not a burst of cold air in.

Dead simple

Type 1 MAX cars have overhead forced-air heating and cooling powered by the same electricity that moves the train (it’s maybe 2% of the total system load). Two thermostats in the return air ducts, on the ceiling just behind each driver cab, aim for a Jimmy-Carter-approved 68 degrees year-round.

Winter radiance

max heater

Like movie franchises, Decemberists albums and mediocre dates, the four generations of MAX cars peaked with the second and third. In 1997, TriMet introduced one of the great joys of Portland winters by rolling out Type 2 MAX trains with floor-level radiators that kick on whenever outside tempeature drops below 55 and inside temperature below 66. On the coldest days, avoid the middle sections of Type 2, 3 and 4 cars – their facing seats still lack heaters underneath.

Everything’s relative

hvacandmore

Starting with Type 3 in 2003, new MAX cars have used an advanced thermostat in their overhead heaters that automatically varies the target inside temperature based on outside temperature. When outside temperature is below 60, the target inside temperature is 66, gradually scaling up to a max of 72 when outside temperature exceeds 72. That means less sweat when you’re in long johns and fewer goose bumps when you’re in shorts.

Backseat oven

Like other autos, TriMet buses get all the heat they need from their engines. This one pumps heat forward through a duct system above the handrails, but the back rows of the bus are always hottest, thanks to heat leakage, less crosswind and (on the new, low-floor buses) being closer to the ceiling.

Electric blessing

left-side heater

Cold feet? Try the seat immediately in front of the rear door on newer buses, and the one opposite the rear door on the very newest ones. Most of the buses without these small heaters were phased out last summer with TriMet’s big bus purchase.

Low-tech thermostat

bus thermometer

All TriMet buses are theoretically set at 72 degrees, but at their size it’s hard to keep to. Bus thermostats are tested in off-hours by a six-inch hand thermometer hung from the extreme front of the right handrail.

Platform warmth

type ii

Here’s a science-approved trick to use while waiting for winter trains: Play a game on your phone. In a 2011 study, a team led by Nicola Swain-Campbell of the University of Otago in New Zealand found that people playing a video game were less sensitive to cold water than people watching television. But gamers should hope the battery lasts until the bus arrives. “If they stop while still cold, it might seem more intense as all their attention switches to the sensation of cold they have been ignoring,” Swain-Campbell said.

Nothing to do then but eat your Slim Jim.

 

Forward, neutral, reverse, off

Oh good, a technical question. Plus an excuse to use a bunch of pics.

Question: What are those signs at Gateway that say “Reverser in Neutral” for?

signal78Example sign near Signal 78

First, a little bit of train anatomy. Here is what’s known as the “master controller” (no, not that one), this particular one is in a Type 2.

mastercontrollerThe master controller: reverser on left, motoring drum handle on right

When starting up a train, operators move the reverser handle first into neutral, rather than to forward or reverse. This essentially lets the train boot up properly. If I understand it correctly (this is getting into more maintenance than operations), there’s also a built-in daily failsafe in the trains that runs a computer check the first time a train is keyed into after midnight, which checks the track brakes and sand, so leaving the train in neutral while it runs this test prevents excessive sand dumping. Anyway, once that’s done, the reverser is used to select the direction of travel.

  • “Forward” is what the public is used to seeing, where the train’s headlights and cyclops (aka railroad light) in the front of the train are lit and the train is moving forward.
  • “Reverse” makes the train able to back up, and so this almost never done since you can’t see where you’re going. This is not to be confused with running reverse traffic, where the train is going the “wrong way” down the tracks but with the operator facing the same direction the train is moving. The only time passengers would be likely to see a train backing up is when cars need to be uncoupled on the mainline.
  • When the reverser is in “neutral” you can’t move the train in any direction, but the train still recognizes that cab as the active cab. The headlights & cyclops will go dark, and will be lit again when the reverser is moved to a direction of travel.
  • “Off” – turns the train propulsion systems off, but does not affect auxiliary power (this is how an operator can leave the train at the end of the line but the lights, HVACs, and doors will all still have power). Type 4s don’t have an off position; neutral serves the same function.

In both directions at Gateway, operators move the reverser into neutral while servicing the platforms. Here’s a westbound red line train coming into the pocket track at Gateway (reverser in forward) and then stopping at the signal to service the platform (reverser in neutral).

forwardneutral

Putting the reverser into neutral here is a communication to buses. The layout of Gateway has buses crossing the tracks on either end of the platforms, so putting the train in neutral darkens the forward lights and lets buses know that it’s safe to cross. Elsewhere on the alignment, operators will also put trains in neutral to let emergency vehicles pass (as well as funeral processions, but those aren’t as common).

neutral platformTrain in neutral at Pioneer Courthouse (not sure why, I’m assuming that an emergency vehicle was passing through). 

Not related to the reverser, but for those of you looking at the propulsion and braking modes in the second picture and are curious, the range of propulsion acceleration is 0.3 mph/sec in P1 to 3 mph/sec in P5. That would be a very rough start, so trains don’t leave platforms in P5. The braking has the same range of deceleration from B1 through MSB (maximum service brake, the highest level of braking used in normal service). On the bottom is the maximum brake, reserved for emergency stopping as it decelerates at a rate of 3.2 mph/sec. In the middle, MP is the minimal amount of propulsion you can use, coast is neither braking nor propulsion, and SM1-SM3 are similar to a car’s cruise control, designed to hold the train at different maximum speeds without going over.

MAX coupling

Not dead. Just resting.

Coupling Info and FAQs

This is going more in-depth on an old anatomy post where couplers were mentioned. The coupler at the end of each MAX car (with the exception of the A-end of a Type 4) allow for both a mechanical couple and an electrical couple between cars. The mechanical couple is what physically keeps the cars connected, and the electrical couple is what allows the cars to communicate. By design, both a mechanical and electrical couple need to be established in order for the train to move.

Although the Type 1s, 2s, and 3s are capable of being coupled into consists longer than two cars, MAX trains do not run in longer consists longer than that. There are rare exceptions to this (e.g. getting a disabled train out of the way), and yes, some 20 years ago trains were brought back into the Ruby Yard in longer consists but the length of city blocks downtown and the subsequent design of all the train platforms limit the length of MAX trains to two cars.

Note: There are several categories of TriMet employees who are qualified to couple and uncouple cars (operators, supervisors, mechanics, etc) but for simplicity I’m just going to go with “operator” in this post.

The Electrical Couple

The coupling process won’t make much sense without describing this first. At the top of the coupler is the electrical coupler head. Under normal conditions, this is either coupled to another train or covered, but occasionally one with the cover up will sneak through ground inspection without being noticed (or alternatively the operator will forget to switch it back after uncoupling cars).

Electrical coupler head on a Type 2 with the cover raised

There are two positions for the electrical coupler head – electronically isolated and electronically normal. If one or both electrical heads between coupled cars are in the isolate position, there will be no electric communication between the cars. When coupling cars, the first goal is to establish a good mechanical couple, and to do that the car doing the couple will be electronically isolated at the beginning of the process.

This switch inside the cab controls the electric coupling of the train

Coupling cars

First, as with just about everything else done with the trains, the operator will get permission from Control before coupling. Next, they’ll do a ground inspection of the car they will be coupling to in order to ensure there aren’t any safety concerns, such as personnel working on or around the car. They will also make sure that the car they are going to couple to is set to electronically normal. The operator will make three safety stops in the coupling process (because hey, you’re essentially about to drive one train into another train) – the first one car length away from the car being coupled to; the second about 10 feet away, and the third at about 3 feet away to ensure that the couplers of both cars are aligned. Then very slowly, the operator will bring their car forward and couple mechanically to the other car (this happens automatically).

The operator will then perform what’s called a “tug test.” As mentioned in the last section, the car that the operator is in is electronically isolated. When there is no electrical communication between the trains, the brakes will apply. In a tug test, the operator remains in the coupled cab and attempts to put the train in reverse and move. The test is a success if the cars do not move – this shows that the mechanical couple was correctly done because it’s holding the operator’s car (which should otherwise be moving backward) to the car with the brakes applied. If the operator’s train car moves backward, it’s either because the mechanical couple failed and the cars came apart, or the cars were not electrically isolated. A visual inspection of the couplers will also be done.

Next is the “trainline test” which is also done from the coupled cab. The operator will now set the car they are in electrically normal (remember that the car they coupled to is also electrically normal). Now there should be communication between the cars, and the easiest way to test this is to open and close the doors. In the yard, this will be done on both sides of the train, and the operator will watch to see that the doors in both cars open. On the mainline, this will only be done on the doors that are on the platform side for safety reasons. If the trainline test is successful, the coupled cars are ready to go.

The finished product: Two successfully coupled train cars. Note how the electrical coupler heads are raised and the covers are on top of the coupler. When the cars are separate, those will slide down over the electrical head.

Uncoupling Cars

A simpler process – again, always done with permission from Control. The operator will do a safety inspection and then press the “uncouple” button in the coupled cab (pictured in the first section of this post, it has a cover over it to prevent it from accidentally being pressed). Next the operator will back their car from the other one to separate the mechanical couple.

Mainline uncoupling

Uncoupling on the mainline is not preferable, but is sometimes necessary in order to cut a bad car and leave a “sportscar” train in service. The exception to this is, of course, the Type 4s, because they can only be fully operated from one end so they can’t be uncoupled on the mainline.

And then the 4s

The coupling and uncoupling processes above apply to the Type 1s, 2s, and 3s. The 4s are more complicated – as you can see in the above picture, they don’t match the coupler heads of the rest of the fleet. Under each Type 4 cab (the A-end) is  a fold-out mechanical coupler head which can be used to mechanically couple a 4 to any other car to be towed or pushed. Type 4s can’t be electrically coupled to the other types of cars, and are the only cars that have the step of connecting the canon plugs of the cables on either side of the mechanical coupler head to electrically couple.

Mechanical coupler head under the A-cab of a Type 4

COUPLER FAQS:

What’s that bag over the coupler head? (seasonal)

These covers basically work like shower caps and are put over the coupler heads in snow/ice conditions to prevent ice from building up on the couplers. Metal covers used to be used but I don’t remember how long it’s been since they were.

Why is a coupler off-center?

deformation tube bend

The coupler heads are designed to be able to bend around curves in the alignment, so if you see a coupler like this, it isn’t broken. They should be straightened out during a ground inspection, but sometimes one gets missed. The operator or a supervisor will move it back into place when they see it.

What happens if the train cars come apart?

If that were to happen, they stop – the default position for a train car is “stopped” and the loss of electrical communication will apply the brakes in the trailing car, much like how the tug test works. I’ve heard some people are not comfortable riding in the trailing car due to “runaway train” fears if the cars separate, but the purpose of the tests done after coupling is to ensure that that doesn’t happen, so this isn’t something passengers need to worry about.

Today I learned: The more you write the word “coupler,” the weirder it looks.

Sandboxes

This one was mentioned back in the anatomy post, but it comes up often enough in person that I figured it should get its own post.

Question(s): What are those boxes under the seats on the MAX trains? / What’s that buzzing sound?

These boxes sit above either side of the powered wheel trucks and are filled with sand. When the wheels spin or slide on slippery rail, sand is automatically deployed from these to improve traction. This is the source of the buzzing sound you will sometimes hear on the train. Sand is also released to help slow the train in emergency braking situations.