Dave’s
Glossary
of Commuter Rail (and related) terminology
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Dave’s Framingham-Worcester
MBTA Commuter Rail Blog
Date
this page last updated: 1/2/2017
By
popular demand, here is a glossary of railroad, MBTA, and Keolis
terms that are relevant to commuter rail operations. Let me know if
you have a term or abbreviation you need defined. It will always be a
work in progress.
These definitions are primarily intended for the
casual 'civilian' with an interest in railroad terminology, so I
have intentionally simplified some definitions. So if you're a
die-hard railfan
or someone studying for your NORAC
rules test, these definitions may not be sufficient for you. But
if I have made any errors, please let me know.
As always, I'm greatly indebted to the contributors
on railroad.net who made both direct suggestions
for this page and also indirectly contributed by imparting knowledge
onto me or piquing my curiosity to go learn more.
Don’t forget to visit Dave’s
Framingham-Worcester MBTA Commuter Rail Blog. Lots of
helpful info and commentary about the Framingham-Worcester line, but
also helpful info relevant to all MBTA commuter rail.
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Automatic
Block Signal System (ABS)
Control & Signal (C&S)
CTC
(1): Centralized Traffic
Control
CTC
(2): Control Trailer
Coach (see "Control Coach")
Heat
Restrictions,
Heat Kinks, etc.
Trainman: See “Assistant Conductor”
ACSES: Pronounced "access" or "ack-sess."
Advanced
Civil Speed Enforcement System. This is only used on the Northeast
Corridor / Providence line. It is a form of positive
train control which builds on the cab
signal concept to automatically control a train. Basically,
ACSES can initiate an automatic brake application within a set
amount of time if the engineer doesn't do what a speed
restriction or signal requires. ACSES was implemented when the Northeast
Corridor was upgraded
to accommodate high speed Acela service. As a condition
of being allowed to operate trains at speeds up to 150 mph, the
Federal Railway Administration required positive
train control and ACSES is the
system that was developed. It is used not only on the Acela trains
- all trains (freight, commuter rail, and Amtrak) operating on the
Northeast Corridor are required to have ACSES. The system uses
fixed equipment along the tracks and also special equipment on the
train in order to function properly. Due to the use of all
commuter rail equipment on any line (see this discussion for more details), all of the south
side equipment has ACSES - and the equipment is needed in
both the control car and the locomotive. Some control cars do not
have ACSES, and those control cars are kept on the north
side. The bad news is that the ACSES equipment is
understandably some of the most complex components on a train, and
having it breakdown can take a locomotive or control car out of
service. Wikipedia
article
here.
Alerter: see "Deadman
Switch" below.
Assistant
Conductor: A uniformed crew member who works under
the direction of the conductor. Depending on ridership loads and the
length of the train, different numbers of assistant conductors are
assigned to different train trips. Assistant conductors collect
tickets and operate the traps
and doors, but they can also assist with other functions, such as
brake tests, connecting or disconnecting train sets, or operating
manual switches. A train is not required (by law or regulation) to
have assistant conductors. The Commuter Rail contract between the MBTA
and Keolis requires 1 Conductor or Assistant Conductor per 300
passengers. Sometimes referred to as Trainmen or Brakemen (which are
both older, primarily freight train terms). Keolis Assistant
Conductors are members of the Transport Workers Union (an affiliated union).
Automatic
Block Signal System (ABS): To mitigate the chance of train collisions, an automatic block
signal system divides the rail line into discrete sections known
as blocks - each separated by a set of signals. The signal system
then displays appropriate signals to indicate where trains are -
without the intervention of a dispatcher. Between interlockings, the
wayside signals or cab
signals display lights that tell the engineer where another
train is (or what the next signal is). For example, let's imagine
a rail line with three blocks. The first block is occupied by a
train. Therefore the signal between block one and two will display
red - indicating to a following train that block one is occupied.
The next signal away from the first train (between blocks two and
three) will show a yellow signal - indicating that block two is
clear, but that block one is occupied and therefore the signal
between block two and one is red. A train passing this yellow
signal will know that they can expect a red signal at the next
block. How does the signal system know where the trains are? It
uses the axles of the trains to complete a 'track circuit' between
each rail to detect the presence of a train (see video at link
below for illustration of this concept). This is a gross over
simplification of ABS, but it illustrates the point without
filling up this page.
This system has been in use for many years, and has
proven to be reliable and robust (although nothing is perfect). On
the Framingham-Worcester line, the section from Boston to
Framingham is a wayside automatic block signal system (wayside
meaning that the signals are displayed on signal masts (towers)
next to the tracks). In this section, each block is 1-2 miles
long. From Framingham to Worcester, a cab
signal system is used. An interesting feature of the ABS
system is that because it is independent of the CTC,
the dispatcher can neither see nor control what the wayside ABS
signals are displaying. The dispatcher can only control the
signals at interlockings or control
points. ABS system
Wikipedia article here.
This is an old and corny video, but it does a good job illustrating the ABS concept (and
it's only two minutes long!). The automatic block signal system
was invented before traffic signals for cars, and when viewed in
that context, the yellow signal of the railroad ABS system makes
much more sense than the yellow signal on traffic lights. Since
trains are forced to follow a certain path (between switches), the
system can be configured to definitively tell a train what the
signals will be displaying at the next block. So a yellow ABS
signal meaning that the next signal is red makes much more sense
(at least to me) than a momentary yellow for cars at a traffic
light. But you can see how the railroad ABS system was adopted for
car traffic signals.
A wayside automatic block signal along the track is
referred to as an "automatic," and each is numbered with a decimal
number on a small placard under the signal lights: the digits
before the decimal number indicate the closest mile marker, while
the digits after the decimal indicate which track and what
direction. For example, "Automatic 10.2E (east)" is the automatic
block signal near mile marker 10 on track 2 for eastbound trains.
This automatic signal actually exists and is just east of
Auburndale station. You can actually see it on google maps street view from the Mass Pike. Engineers are required to verbally
(over the radio) state the condition ("name") of a signal that is
anything less than "clear," so you may hear an engineer saying
"approach at automatic ten, track 2, east" after which the
conductor will acknowledge the information.
Beacon Park: Former CSX freight yard in Allston. CSX sold the land to Harvard University in May 2003. The MBTA and CSX have perpetual rights to use the yard for railroad (commuter rail or freight) purposes. CSX relocated their freight operations to other locations such as Worcester and Westboro and their use of the Beacon Park yard for freight operations ceased in February 2013. See this post for references.
Bell (1): There is a warning bell on the exterior of the locomotive and
control coach. It must be rung to warn people of the train's
approach at certain places such as grade
crossings, stations, around track workers, and when someone
is observed near the tracks. Most of the warning bells are driven
by the compressed air system, and the engineer manually activates
the bell from the control stand. This bell has nothing to do with
the bell at each
control stand.
Bell (2): The backup communication system utilizing a bell at each
control stand (in the locomotive and
the control coach). See Brake
Test. This bell also rings in the case of a problem in the
locomotive - for example, if the HEP fails,
the bell will ring to make sure the engineer is aware. This bell
has nothing to do with the bell on the exterior of the locomotive
or control coach (see above).
Blind Coach (or car): a passenger carrying coach that is NOT a control
coach. All 'blind' coaches have three digit numbers. They are
formally known as "BTC" for Blind Trailer Coach. One or two digits
or numerals are added after the BTC abbreviation to designate
what 'model' or 'series' the coaches are from. A roster of coaches
is available here.
Boston & Albany: The Boston & Albany is one of the oldest rail
lines in North America, and we get to ride on it every day! The
Framingham-Worcester commuter rail line is the easternmost 45 mile
section of the former Boston & Albany railroad. The first
section from Boston to West Newton opened in 1834 - along the same
alignment used today! The line was fully operational from Boston
to Albany in 1841. It is also referred to as the "Boston
Subdivision" as this is what it (the entire line from Albany to
Boston) was called when Conrail and now CSX used it / owned it as
part of their network of national freight service. Wikipedia article here.
Boston Engine Terminal (BET): The old but most commonly used name for the
Commuter Rail Maintenance Facility (CRMF) in Somerville, where
most of the maintenance for locomotives and coaches is conducted.
This is the primary repair facility where the most complicated
work can be performed on trains, including changing engines on
locomotives, replacing wheel sets on locomotives or coaches, and
everything smaller than those tasks. Since it is on the north
side, trains needing repairs or maintenance that can't be done on
the south side must make the somewhat complicated trip across the
Grand Junction (see below) to get from the south side to the BET.
Back
to Top
Boston Landing station: new station slated to open in 2016. See this blog post and
then read this one.
Brake Test: Before departing from a terminal (beginning of a
trip), a brake test must be conducted to confirm that the
compressed air brake system is operating properly. A crew member
goes to the rear of the train (which could be the control car or
the locomotive, depending on the direction of operation), and the
engineer releases and applies the train air brakes from the
controls at the front of the train. The crew member at the
opposite end of the train can observe the compressed air pressure
in the brake system on a gauge and reports back to the engineer if
the system functions properly. This report can be by radio or by
using the bell system - there is a bell at the control stand
of both the locomotive and the control car that can be rung from
the other location. This communication method predates radios and
is still installed on passenger trains as a backup. You may hear
the bell being rung to acknowledge the brake test if you are in
the control car at the start of a trip (such as at South Station
awaiting departure). During the brake test, the train won't roll
away because the brakes on the locomotive are separate and remain
applied. The train may roll slightly during the brake test because
the couplers (actually draft gear) may 'stretch' or 'contract'
allowing the train to get slightly longer or shorter, making some
cars roll back or forward.
A brake test is also required after resetting the
brake system after any application of the emergency brake function
and also after coaches or locomotives are connected to
makeup a train set. When a train is connected to another train (for
example, to 'rescue' a dead set), a brake test would also be
required.
Bubble: The little office shed thing at the foot of track 10 at
South Station. It looks like a temporary structure, and is raised
off the ground and accessed by a small stairway. The trainmaster
(see below) works here.
Bustitution: Slang
term for substituting train service with buses.
Cab Signals: The next generation of automatic block signaling
(see above), cab signals move the display of signals from the
masts or towers along the tracks into the cab. A special display
in the cab of the locomotive (or control coach) gives the engineer
a continuous indication of the signal currently in effect in the
block (see ABS above) that the train is in. This system increases
safety because the engineer does not have to rely on memory to
remember the last signal passed - it is right there to see. And
changes in signal indication can be transmitted much quicker to
the engineer, without the delay of waiting for the wayside signal
to come into view. On the Framingham-Worcester line, the section
from Framingham to Worcester has a cab signal system in use (and
therefore there are no wayside ABS signals). Wikipedia article here. See also "ACSES" and "Positive Train Control."
CETC: Pronounced "see-tek" - Centralized Electrification and Traffic Control. Technically this is the formal name of the CTC (see below) system used by Amtrak for the entire Northeast Corridor. This system controls not only the trains on the Northeast Corridor via ACSES (see above), but also the electrical loads and electrical distribution associated with the Amtrak electrified train system. Since the dispatchers working the MBTA / Keolis south side lines share the dispatch theatre at South Station with the Amtrak Northeast Corridor dispatcher, the South Station dispatch theatre is commonly referred to as CETC, but this is not technically accurate, since "CETC" is technically a computer system. And since the Framingham / Worcester line doesn't have any electrification, nor is it owned or operated by Amtrak, the dispatch system for the Framingham / Worcester line isn't part of CETC. The newly renovated South Station dispatch theatre opened on June 26, 2015. Picture here. I toured the old dispatch theatre years ago. Photo here. This picture shows a dispatch screen and how to read it. The track layout at South Station has changed, but the theory of how to read the screen is still the same.
Channel: Railroads are allocated approximately 95 distinct
frequencies for communications. The AAR (Association of American
Railroads) manages the assignment of these frequencies. For
convenience, each frequency is assigned a channel number. Each
railroad radio has the capability to transmit and receive on
different channels, so when referring to channels, they are
typically referred to in a pair. Keolis
conductors and assistant conductors carry portable radios with a
digital LED display that shows what channels they are tuned to -
so if you look at the radio you will see "20-20" or something
similar. For the Framingham Worcester line, there are only two
primary channels that are in use:
"Worcester Line" dispatcher - channel 20/20,
160.410 MHz. In use from
Worcester to CP COVE near South Station.
"Terminal Dispatcher" - the Amtrak South Station
terminal dispatcher, channel 64/64, 161.070 MHz.
In use from CP COVE into South Station.
You may hear the train crew saying something like
'going over' on the radio as a reminder for all of them to change
the channel on their radio as they depart or approach South
Station near CP COVE.
Other channels that are of interest:
"Mechanical Help Desk" - channel 90/90, 161.460 MHz.
Usually referred to as just the "help desk." This is
used for train crews to talk to Keolis management engineers for assistance
troubleshooting problems with equipment. The help desk is actually
located at the CROCC in Somerville (see above).
"Framingham North Yard" - channel 64/64, 161.070 MHz. The CSX
freight yard in Framingham uses this channel for yard operations.
There is a yard manager in the office / operations building north
of the Framingham train station who coordinates yard operations
and goes by the call sign "Framingham North Yard." (Since it is so
far away from South Station, there is no interference with the
South Station dispatcher).
"Framingham Subdivision" - channel 21/21, 160.425 MHz. See "Framingham
Subdivision" below.
Dispatchers can talk to train crews across wide
distances because there are multiple transmit and receive antennas
across each train line. The dispatcher can control what antenna is
used to transmit and receive and selects an antenna based on the
proximity of the train. An antenna station is located at the
Framingham station - look for the big antenna at the east end of
the station! Communications can be sent to and from the antenna
stations and the dispatcher's desk via dedicated telephone lines,
a separate radio system, microwave signals, or dedicated fiber
optic cables owned by the railroad. I have no idea how the MBTA /
Keolis
does it.
More information on railroad frequencies here.
See "Dispatcher" definition below for more
frequencies.
Clock Facing: A schedule where the service departs at the same minute of each hour. For example, if a train left Worcester at 6:00 AM, 6:30 AM, 7:00 AM, 7:30 AM, 8:00 AM and so on, that schedule would be said to be 'clock facing.' The advantage is that a rider doesn't need to memorize a complicated schedule - only the particular 'minutes' that a train stops at their particular station. This kind of schedule can be setup with any interval, and the interval does not need to be even. For example, a schedule with trains arriving / departing at x:00, x:23, x:35, and x:50 would be odd but still be clock facing, as long as that pattern repeated every hour (for at least a couple of hours). Obviously most clock-facing schedules have equal intervals, not only to maximize the logic but also the distribution of train sets. Wikipedia article here.
Control Coach (or car):
a passenger carrying coach, outfitted with controls for the engineer
to be able to operate the train in "push-pull" mode (see below).
Similarly, they have headlights, a horn, and other features that
allow them to be used at the front of a train set. The control coach
also has red 'marker' lights that are illuminated to indicate the
location of the rear of the train when the train is being pulled.
When operated in the 'push' mode, the engineer is at the control
stand of the control coach and there is nobody in the cab of the
locomotive. Therefore note that the locomotive must have specialized
equipment to allow for 'remote' operation from the control coach.
All MBTA commuter rail control coaches have four
digits as the number of the coach, and the first digit is always
"1." Of course there is an exception to every rule: coaches 1600
through 1624 were originally control coaches but their controls
have been deactivated and are now just blind trailer coaches.
Control coaches are formally called "CTC" for
Control Trailer Coach. One or two digits or numerals are added
after the CTC abbreviation to designate what 'model' or 'series'
the coaches are from. A roster of coaches is available here.
Since every train set / consist needs a control car
(and usually each set only has one), each control car has an AED. For more information on why the MBTA added AED's to each
train, read this blog post, especially the last few paragraphs.
Control Coaches are sometimes deridingly nicknamed
'coffin cars' because passengers sitting in a control coach do not
have the buffer of a locomotive in the event of a collision.
Fatalities and injuries, therefore, are more likely to the
occupants of control coaches than coaches further back in the
consist (when the train is in 'push' mode and the control car is
in the front). For example, all five passenger fatalities aboard
the MetroNorth train 659 collision in February 2015 were
in the control coach. MetroLink,
in Los Angeles, implemented a policy of placing a locomotive in
front of all control coaches in response to a similar train vs. vehicle collision. NOTE that one of the contributing factors in the
MetroNorth
accident and the subsequent fatalities was the under-run third
rail, which is NOT present on the MBTA commuter rail system.
Also note that MetroLink
has MANY more grade crossings than the MBTA, and therefore is at
much higher risk for train-vehicle collisions. Remember that
train travel is VERY safe, and you're more likely to get killed
when you jaywalk across the street after you get off the train
in Boston. I sit in the control coach every day without worrying
about it. But you will notice that the MBTA only uses control
coaches for passengers during rush hour when the most seats are
needed. The control coach is the first coach to be 'closed off'
to passengers when ridership is lighter. Control coach Wikipedia article
here.
Control Stand: The console of controls used by the engineer to operate
the train. The control stand is on the right hand side (known as
the 'engineer's side') of the locomotive or control coach (as
viewed from the train operating forward). This means the train
is operated from the opposite side than a typical American car
(where the driver sits on the left).
Conductor: The person in charge of a train. On the commuter rail, the
conductor is a uniformed member of the crew, and also collects
tickets in the passenger coaches. However, their primary
responsibility is the safe operation of the train. No train can
operate without a conductor. The conductor must be qualified for
the rail line they are working on - qualifications involve
knowing the locations of signals, interlockings, speed limit
changes, and various other physical conditions of the line. Each
train set has one conductor. See also Engineer and Assistant
Conductor. Keolis
Conductors are members of the Transport Workers Union (an affiliated union).
Consist or Set: a combination of a locomotive and coaches that forms a
train.
CP: Controlled point. A location on the railroad where
the signals are controlled by the dispatcher (believe it or
not, the other signals are not controlled by the dispatcher -
see "Automatic Block Signal" above). On the Framingham Worcester
line, each CP also has crossover switches so a train can
change from one track to another. The controlled points along
the Framingham Worcester line are known as "CP XX" where "XX" is
the closest mile marker number, such as "CP 21." This is an
artifact of Conrail and CSX terminology that persists along the
Framingham-Worcester line. Other MBTA commuter rail lines have
actual names for their controlled points, such as "Forest,"
"Plains," "Thatcher," etc. The only exceptions on the Framingham
Worcester line are the two controlled points closest to South
Station. Just outside of South Station is controlled point
"TOWER ONE" and just west of that is controlled point "COVE"
(both of which are under the jurisdiction of the South Station
terminal dispatcher, so some would argue those controlled points
are not actually on the Framingham-Worcester
line). The locations of the controlled points on the
Framingham-Worcester line are shown on the map I created.
CP Yard: Name of the yard adjacent to the former General Motors
assembly plant (now Adesa car auction
facility) in South Framingham. CP stands for "Constructive
Placement," which is a term related to demurrage. After the GM plant ceased building cars, an autorack unloading facility near the CP Yard was
still used for offloading new cars from freight trains (and transloaded onto tractor trailers for final delivery
to dealerships). That freight service ended in 2009, with the
autorack service
relocated to the relatively new CSX autorack facility in
East Brookfield, MA. The switch from the Boston and Worcester mainline to the CP
Yard is just west of the Framingham station and within the limits
of the CP 22 interlocking. The CP yard is sometimes used for
'overflow' freight traffic when Nevins Yard or the Framingham
North Yard do not have capacity. The line leading to the CP Yard
was also known as the Holliston Industrial Track, since it led to
Holliston and eventually Milford. The rail line south of Whitney
Street / Eliot Street in Sherborn / Ashland has been formally
abandoned as a railroad, and portions of the Holliston Industrial
Track in Holliston and Milford are now the Upper Charles Rail
Trail.
At one time, the Holliston Industrial Track was
connected to the Framingham Worcester mainline with a 'wye' (see
below) connection. The west side of the wye is all that remains -
the east side of the wye connected to the mainline just west of
the original Framingham station building (now the Deluxe Depot
Diner). The right of way still exists between the parking lot for
Republic Plumbing Supply and the Town of Framingham commuter
parking lot. This Town of Framingham parking lot is actually on
the 'infield' of the wye - between both legs of the wye. Before
push-pull commuter train operations, MBTA commuter trains would
use this wye to reverse direction back to Boston.
CRMF: Commuter Rail Maintenance Facility in Somerville, MA. See
"BET" above.
CROCC: "Commuter Rail Operations Control Center." Located in
Somerville, this is where all the
MBTA/Keolis north side commuter rail
dispatchers are located (all of the south side line dispatchers
are located at South Station). The Mechanical Desk or "Help Desk"
(AAR channel 90/90) is also at the CROCC (for both north and south
sides).
C&S: Control and Signal department. This is the department or
division of Keolis that is
responsible for maintaining and repairing the signals, switches,
crossing gates, and other control type devices on the railroad
(where owned by the MBTA).
CTC (1): Centralized Traffic Control. A computerized dispatch system,
where a dispatcher controls the switches and some signals (see
"Automatic Block Signals" above) for a rail line. See "Dispatcher"
below. A CTC can be programmed to prevent the dispatcher
from aligning some switches and signals in an arrangement that
would cause a conflict (or collision) between trains. CTC is a
generic term (see also CETC above).
CTC (2): Control Trailer Coach (see "Control Coach" above).
Deadhead: See "Non-revenue" below.
Deadman Switch: With only one person at the controls of the train, something
is needed to mitigate the risk of a runaway train due to the
incapacitation of the engineer. Having a deadman switch that is continuously held down
(like the handle on a lawn mower) is not ideal, since it can be
defeated by leaning on it (and the leaning could be by an
incapacitated engineer!). So the deadman switch in use on modern locomotives and
control coaches is a button that must be momentarily pressed at
certain time intervals. The button begins by flashing to 'request'
a push, and if it isn't pushed in a certain amount of time, it
starts sounding a noise. Eventually, after it starts flashing and
then sounding, if it still isn't pushed, it sends a signal to the
controls of the train to stop the engine and apply the brakes to
stop the train. The deadman switch is
sometimes called an alerter, although technically speaking the
alerter is something connected to the deadman
switch system but different than the actual deadman switch. Wikipedia article here.
Defect Detector: A device at a fixed place on the railroad that monitors passing trains for problems with their equipment. They can be used to detect dragging equipment (something broken and dragging, which isn't good), or overheated wheel bearings, among other problems. There is one defect detector on the Framingham Worcester line just west of the Ashland station and another in Grafton. After a train passes the defect detector in Ashland (and there are no defects detected), a really corny automated voice comes over the radio and says "CONRAIL ASHLAND MASSACHUSETTS TRACK xx NO DEFECTS OVER." Even though CSX took over operation of the line from Conrail in 1999, and the MBTA purchased the line in 2011, the silly voice still says Conrail. If a defect detector detects a defect, the voice will transmit on the radio and tell the engineer to stop the train. The engineer is obligated to stop the train and have the crew inspect the train to identify (and correct, if possible) the defect. The advantage to railfans is that defect detectors are very useful to determine where a train is when listening to the radio via a scanner. Wikipedia article here.
Delay In Block: Have you ever seen those "D.I.B" signs near some stations?
That stands for "delay in block" (which is rule 504 in the current
NORAC rules). This is one of the more complex issues in this
glossary, and it took me a while to get my head around it. So
please read "Automatic Block Signal," "Home Signal," and "Distant
Signal" first. Delay in Block is a concept invented as a result of
a fatal train accident - the 1996 collision of a Maryland Commuter
Rail train ("MARC") with the Amtrak Capitol Limited. You can read
about that here. But to explain DIB, let's recreate the MARC
accident as a hypothetical situation on the Framingham Worcester
line. If you need to, use the map to get some idea of what we're talking
about.
First, the setup: CP 21 is the home signal in
downtown Framingham. West Natick station is within the block
between the CP 21 home signal and the automatic signals at
milepost 18 (westbound automatic 18 is therefore the 'distant'
signal to CP 21). Scenario:
A westbound passenger train passes the automatic 18
signal with an approach indication. This approach indication at
automatic 18 indicates that the interlocking at CP 21 is either
occupied or 'not ready' and a stop signal should be expected at CP
21. As planned, our westbound passenger train stops at the West
Natick station. Not being able to see CP 21 from the West Natick
station (it's around a curve and miles away), our westbound
passenger train departs West Natick and FORGETS that they had
passed an approach signal and accelerates to track speed. This
human error is somewhat understandable - if there hadn't have been
a stop, the train would have started decelerating after the
approach signal and the engineer's thought process would have been
continuous to the stop signal at CP 21. But the station stop
interrupts this thought process and the natural action after the
station stop is to accelerate up to track speed. By the time the
engineer sees the stop indication at CP 21, it is too late and the
train can't stop at CP 21. It passes through the CP 21 signal and
collides with a train within the CP 21 interlocking. Which is
generally a bad thing.
But wait! That can't happen! We have DIB! The Delay
in Block rule is exactly for this problem. Simply put, when the
Delay in Block rule is in effect, a train that makes a station
stop between a distant and a home signal must then approach the
home signal PREPARED TO STOP at no more than 40 mph.
So with DIB in effect, let's go back to our
scenario: our westbound train making the station stop at West
Natick is not allowed to accelerate to track speed leaving West
Natick, and is reminded of this by the yellow "DIB" sign just
after West Natick station - right where the engineer is sitting
during the West Natick station stop. If making the West Natick
stop, the train has to be prepared to stop before it reaches CP
21, no matter what the automatic 18 said. Problem solved.
If you understand this concept, you pass, you're an
official foamer (see
below).
Diesel-Electric: All MBTA commuter rail locomotives are diesel-electric locomotives. Unlike with a highway truck, where the diesel engine is mechanically coupled (via a driveshaft) to the drive wheels, a diesel-electric locomotive uses a combination of a diesel engine (the "prime mover") and electricity to move the train. The prime mover transmits rotational energy to a generator that produces electricity. This electricity is transmitted (via cables) to the electric traction motors that turn the drive axles of the locomotive. Note that the 'diesel-electric' type of locomotive does not refer to the electricity produced by the head end power (HEP) unit. A freight locomotive without a HEP is still a diesel electric locomotive, since the 'electric' in 'diesel-electric' refers to the electricity used by the traction motors. This website has many pages that go further into detail regarding the diesel electric locomotive.
Dispatcher: The individual responsible for managing the traffic flow of
a rail line. For the Framingham-Worcester line, there is a single
Dispatcher (for each shift) for the "Worcester Mainline" (more
details below). This Dispatcher sits at the CETC theatre in South
Station. From this position, the Dispatcher can talk to train and
maintenance crews via the radio system (see "channel" above) and
also operate switches and signals at interlockings. The Dispatcher cannot remotely control
or stop trains. The Dispatcher is not responsible for assigning
equipment and not necessarily responsible for determining what to
do when trains break down. The Dispatcher does NOT control
'customer service' related functions such as the LED signs at
stations, the T-Alerts text messages, or the @MBTA_CR twitter feed
(all of those are managed by the Keolis Customer Service department). Each
Dispatcher reports to the Assistant Chief Train Dispatcher and
Chief Train Dispatcher. In the case of out-of-the-ordinary
situations,
the Chief Train Dispatcher would collaborate with the Trainmaster, "Incident Commander," mechanical staff, and/or
the engineering department (depending on the particular situation)
to implement workarounds for managing train traffic.
The primary responsibility of each Dispatcher is
the safe movement of the traffic on 'their' tracks. The secondary
responsibility is the on-time movement of the traffic on 'their'
tracks according to the published schedule (actually the employee
time table, which is more comprehensive than the schedules we
see). Keolis, Amtrak, and Pan AM (PAR) train
dispatchers are members of the American Train Dispatchers Association (an affiliated union). See also "CETC" above.
The radio frequency that each dispatcher uses is
listed below - which have been updated as of 2/1/2016 when some
new channels were activated. See "Channel" definition above for
more information about radio channels.
<this
information
compiled from a variety of sources, including railroad.net and scan-ne.net>
South Side Dispatchers
There are a number of dispatchers at the CETC
theatre in South Station for the entire south side (and beyond),
as listed below. Each dispatcher is referred to as a 'desk.'
"Exclusive" and "inclusive" below indicates who controls a
particular interlocking.
"Amtrak Terminal" dispatcher: Amtrak employee. Responsible for South Station.
Limits of responsibility are on the Framingham-Worcester and
Providence / Northeast Corridor lines from CP COVE (inclusive)
into South Station and on the Old Colony and Dorchester branch
lines from TOWER ONE (inclusive) into South Station. Channel 54/54, 160.920 MHz
"Worcester Mainline" dispatcher: Keolis employee. Responsible from CP COVE
(exclusive) to CP 45 (exclusive) in Worcester. Channel
20/20, 160.410 MHz
"Old Colony" dispatcher: Keolis employee. Responsible for Old Colony
lines (Greenbush, Plymouth / Kingston, and Middleboro) lines from
CP CABOT (exclusive) southward. Channel 41/41, 160.725 MHz
"Corridor" dispatcher: Amtrak employee. Responsible for the Providence
line / Northeast Corridor from CP COVE (exclusive) to CP JUNCTION
(inclusive) (near Canton, MA). Channel 54/54, 160.920 MHz
"Main Line" dispatcher: Amtrak employee. Responsible for the
Providence line / Northeast Corridor from CP JUNCTION
(exclusive) to Cranston, RI (except coverage extends to Mystic CT
when "South County" is off-duty, which is Monday - Friday 3 PM -
11 PM and weekends as noted below). Channel 54/54, 160.920
MHz
"South County" dispatcher: Amtrak employee. Not on duty Monday - Friday 3 PM
to 11 PM nor on weekends. When not on duty, territory covered by
"Main Line" dispatcher. Responsible for the Northeast Corridor
from Cranston, RI to Mystic CT (obviously not dispatching
MBTA / Keolis trains, just included here for
completeness). Channel 54/54, 160.920 MHz
"Dorchester" line dispatcher: Amtrak employee. Responsible for
Dorchester Branch from CP TOWER ONE (exclusive) to CP
SOUTH BAY (inclusive) and also the Middleboro
Main Line (Old Colony) from CP TOWER ONE (exclusive) to
CP CABOT (inclusive). Channel 92/92, 161.490 MHz
"Branch line" dispatcher: Keolis employee. Responsible for the Dorchester
Branch from CP SOUTH BAY (exclusive) to Readville,
and also responsible for the Needham, Stoughton and Franklin
branches. Channel 54/54, 160.920 MHz
"Mass Coastal" dispatcher: Mass Coastal is actually a subsidiary of Iowa Pacific
Holdings. Iowa Pacific conducts dispatching of the Mass Coastal
lines from their central office (so obviously this dispatcher
isn't sitting at the CTEC in South Station). This dispatcher is
responsible for the Mass Coastal controlled lines which the "Cape
Flyer" uses to get from Middleboro to Hyannis. Mass Coastal also
dispatches the "Framingham Secondary," which includes the section
of track where the Foxboro / Gillette Stadium MBTA station is.
Channel 21/21, 160.425 MHz.
North Side Dispatchers:
Just for completeness, here is the list of
dispatchers for the North Side. Keolis dispatchers for the North Side are in
the CROCC (see above), while the Pan Am dispatchers are at the Pan
Am offices. Each dispatcher is referred to as a 'desk.'
"Exclusive" and "inclusive" below indicates who controls a
particular interlocking.
"Terminal" dispatcher: Keolis employee. Channel 87/87, 161.415 MHz. Responsible for:
1) Fitchburg main line from North Station to CP
SWIFT (inclusive)
2) Western Route (Haverhill line) from North
Station to CP FELLS (inclusive) - but see "Valley"
dispatcher below
3) Eastern Route (Newburyport line) from North
Station to CP READING JUNCTION (inclusive)
4) New Hampshire Route (Lowell line)
from North Station to CP SOMERVILLE JUNCTION (exclusive)
5) Grand Junction track (see "Grand Junction"
below)
"Valley" dispatcher: Keolis employee. Channel 14/14, 160.320 MHz. Responsible for the Western Route
(Haverhill line) from CP TOWER A (exclusive) to CP CPW-WJ
(Wilmington Junction) (exclusive). This desk is only staffed
from Monday-Friday 7AM-11PM. At other times, territory is
dispatched by "Terminal" dispatcher or "Boston East" dispatcher as
described elsewhere.
"Boston East" dispatcher: Keolis employee. Channel 14/14, 160.320 MHz. Responsible for:
1) Gloucester branch from CP READING
JUNCTION (exclusive) to Newburyport
2) Western Route (Haverhill line) from CP
FELLS (exclusive) to CPW-WJ (Weekends and 11PM-7AM daily)
"Boston West" dispatcher: Keolis employee. Channel 32/32, 160.590 MHz. Responsible for:
1) New Hampshire Route (Lowell line) from
CP SOMERVILLE JUNCTION (inclusive) to CPF-BY (Bleachery) (exclusive)
2) Wildcat Branch
3) Fitchburg Route from CP SWIFT (exclusive)
to CPF-WL (Weekends and 11PM-7AM daily)
"Fitchburg" dipsatcher:
Keolis
employee. Channel 32/32, 160.590 MHz. Responsible for Fitchburg line from
CP SWIFT (exclusive) to CPF-WL (exclusive). This desk is only
staffed from Monday-Friday 7AM-11PM. At other times, the
territory is dispatched by the "Boston West" dispatcher.
"PAR District #2" dispatcher: Pan Am Railways employee. Channel
70/94, 161.160 MHz/161.520 MHz. Responsible
for:
1) New Hampshire Route (Lowell line) from CPF-BY (Bleachery) to CPF-LO (Lowell)
2) Western Route (Haverhill line) from CPW-WJ
(Wilmington Junction) (inclusive) to CPF-273 (Plaistow / State
line)
3) Danvers Industrial Track
4) Medford Industrial Track
"PAR District #3" dispatcher: Pan Am Railways employee. Channel 70/94,
161.160 MHz/161.520 MHz. Responsible
for
Fitchburg line from CP CPF-WL (The Willows) (inclusive) to Wachusett
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Distant Signal: The 'last' signal before a home signal (see below) at an
interlocking. If there are no automatic block signals between interlockings, a home signal could also be a distant
signal for the next interlocking. This exact situation exists on
the Framingham Worcester mainline at CP 3 westbound, CP 4
eastbound, CP 21 westbound, and CP 22 eastbound (and maybe
others). A distant signal has a yellow sign with a black "D" on it
to indicate it is a distant signal. A distant signal designation
is used to indicate to an engineer that they are approaching a
home signal and certain conditions / considerations apply. See
also "NORAC" below and "Delay In Block" above.
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Double: Slang term for a bi-level coach. The different models of
bi-level coaches have from 173 to 185 seats, depending on exact
configuration and manufacturer. Kawasaki built the majority of the
doubles, with the first order of coaches entering service in
1990-1991. Hyundai-Rotem built the newest 'doubles' which have
all been delivered. However, some of the new "Rotems" are at Davisville, RI undergoing warranty modifications,
while some coaches are still due to rotate down to that facility
for the warranty modifications. The Rotems have been
widely criticized for shoddy workmanship, and the entire order was delivered very late. A roster of coaches is available here.
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Double Draft: Two trainsets coupled together and operating as one train.
On some lines, a scheduled double draft (usually non-revenue, see
below) is used to position equipment for the AM commute, either
because of a lack of layover space or some other operational
consideration. For example, a double draft would depart Boston
very early in the morning and upon its arrival at the end of the
line, the double draft would be split into two separate trains for
service back into Boston as two different trains. In years past, a
double draft has been used for this purpose on the
Framingham-Worcester line, but the current schedule does not
include any scheduled double drafts on this line. Double drafts
are also used / encountered when locomotives fail - typically the
next train operating behind the dead train will 'tie onto' the
dead train and push it along the remainder of it's trip. The problem with this is that if
both trains are carrying passengers, the double draft will
typically have to make two stops at each station, since the double
draft is too long for all the coach doors to line up with the
station platform.
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DTMF: Technically, DTMF stands for Dual Tone Multi Frequency. You
know it as the noises that your phone makes when you push the
different number keys. The radio system in use on the Framingham
Worcester line has DTMF capability. Each radio has a dial pad on
it, and it works just like your telephone - push the buttons and
the tones are transmitted over the radio. The reason this is
interesting for us is that the Concord Street grade crossing in
Framingham is manually controlled with DTMF tones in the eastbound
direction. As a train pulls into Framingham station headed east,
it will encounter a stop signal at the far east end of the
platform - before the Deluxe Diner Depot and before Concord
Street. This is actually CP 21. If the dispatcher has aligned the
CTC system properly, the engineer can enter a two digit DTMF code
into the radio to 'request' that the signal system close the
Concord Street crossing gates and then give the train a clear
signal at CP 21. The advantage to this is that the Concord Street
crossing gates can remain up and allow vehicle traffic to proceed
normally through downtown Framingham while the train is in the
station being loaded with passengers. And it eliminates the need
for the train crew to call the dispatcher and ask him or her to
activate the signal. Before the MBTA bought the line, the same
system existed, but without DTMF tones. There is a little box at
the east end of the platform (one for each track) with a push
button inside that has the same functionality. The push button
still exists and can be used as a backup to the DTMF method. Also
interesting to note is that once the sequence is initiated, the
train must proceed past the CP 21 signal within a set period of
time, otherwise the signal reverts back to stop. It then can't be
reactivated for a certain period of time (sometime called 'burn
down'). For this reason, the train crews are very reluctant to
stop the trains to pick up late passengers when leaving Framingham
eastbound.
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Engineer: the operator of the train. The engineer reports to the
conductor, who has overall responsibility and authority for the
train's operation. The engineer sits at the control stand of the
locomotive (for outbound trips) or the control stand in the
control coach (for inbound trips), where he/she uses the levers
and controls to operate the train. The engineer usually conducts
primary radio communications with the dispatcher. On MBTA / Keolis trains, the engineer does not wear a
uniform. Most engineers are conductors prior to being promoted to
engineers (after extensive classroom training and on the job
training). Each engineer must be qualified for each rail line they
work on, and those qualifications must be kept current and updated
periodically. Qualifications involve knowing the locations of
signals, interlockings,
speed limit changes, and various other physical conditions of the
line - essentially the engineer must memorize the entire
route. Keolis Engineers are members of the Transport Workers Union (an affiliated union).
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Engine Burn: Term used to describe damage to rail caused by wheel slip.
An extreme example
is pictured here(supposedly a freight train had the train brakes on but the
locomotive was allowed to operate). Typically the damage is much
less severe, such as this
example from an observant Worcester line rider. This
damage was on Track 1 at the Grafton station on 11/17/15. See
"wheel slip," "slippery rail," and "sand" definitions also.
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EOT or ETD: End of Train device. Not used on commuter rail services,
since the control coach provides the same functionality. The EOT
is used on freight trains as a replacement for cabooses. The EOT
provides information to the engineer in the cab of the train
regarding certain operating parameters such as brake air pressure.
Some EOT's allow the engineer to apply the emergency brakes to the
rear of the train at the same time as the front, enabling more
rapid brake application. Wikipedia article
here.
"F" letter
sticker / stencil on side of locomotive or coach designating the
front of the locomotive or car. Here is a picture of the "F" on a locomotive and here's a real old "F" on a control coach.
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Flat or Single: Slang term for a single level coach. The different models of
single level coaches vary in seating capacity from 88 to 127. The
primary reason for the wide range of seating capacity is because
the MBB (Messerschmitt-Bolkow-Blohm) manufactured single level coaches
have 2 seats on both sides of the aisle (2x2 seating), while the
other coaches have 2 seats on one side of the aisle and 3 seats on
the other (2x3 seating). The oldest coaches originally built by
Pullman-Standard in 1978-1979 were rebuilt in 1996. Other than
that, the rest of the singles were all manufactured between 1987
and 1990.
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Foamer: Term used to refer to a railfan,
usually with derogatory connotations. I wear my "foamer"
title with pride! Since many railfans
have detailed technical knowledge regarding the operations of a
railroad, they can be very effective spotters for safety issues and
anything out-of-place.
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Form D: During normal operations, the movement of trains is governed
solely by the signal and computerized dispatch system. However, in
some circumstances (such as failure of the signal system), an
alternate method of controlling the movement of trains is needed.
This is done with a system of 'warrants' - a warrant is filed for
the train and track in question and those warrants are kept by
both the train crew and the dispatcher. By referring to the
warrants in effect, the dispatcher and train crew have
confirmation of what track they are authorized to operate on.
Under the NORAC rules (see NORAC below), a track warrant is known
as a Form D. The form has specific numbered line items, which act
as a checklist for the dispatcher and train crew. Sometimes you
can hear a dispatcher give the required entries for a Form D to a
train crew - for example, in the case of a failed grade crossing
gate, a Form D may be required for the train to proceed past the
grade crossing, and the Form D will specify the slower speed or
other precautions that must be taken. The Form D is entered into a
computer at the dispatcher end, but that is not 'interlocked' to
the CTC (see above) - the dispatcher must manually insure that
adequate protections exist for whatever situation is requiring the
Form D. On the train crew end, the Form D is an actual piece of
paper that must be filled out, and it cannot be filled out while
the train is moving. If you hear a train crew refer to a delay
related to paperwork at a location 'out on the line' away from
South Station, chances are they are receiving a Form D from the
dispatcher over the radio. When departing a terminal to begin a
trip, you will typically hear the conductor tell the engineer: "No
D's, no changes, OK to proceed on signal indication." The
reference to "D's" is telling the engineer that no Form D's are in
effect for the trip.
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Framingham Subdivision: The freight line ( now owned by MASS DOT) that leads from Framingham through Sherborn to Walpole and
Mansfield, where it connects to the Northeast Corridor. The switch
off the Framingham Worcester mainline is just to the east of the
Concord Street crossing and within the limits of the CP 21
interlocking in downtown Framingham. There is currently one round
trip CSX freight train to/from Framingham and Mansfield on this
line. B731 departs Framingham around 11 PM and heads south to
Mansfield (and eventually to Readville via the Northeast Corridor). It returns
to Framingham in the AM, and usually heads west through Framingham
station to Nevins Yard between P506 and P508 (about 7:30 AM). It
holds south of Blandin Avenue until the Worcester Line
dispatcher gives it permission to proceed onto the main line (if
it pulled all the way up to near the main line, it would foul
(block) the Blandin Avenue grade crossing, tying up vehicle
traffic in South Framingham). Sometimes, if it is a short train
with not as many freight cars as usual, it will run up to Nevins
Yard between P582 and P506 (about 7:00 AM).
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Frequency: see Channel above.
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GPS: Global Positioning System. Each train has a GPS receiver
that is used to transmit it's position back to Keolis Customer Service via the PTIS system
(see below). Note that this GPS data is NOT used to dispatch and
control trains.
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Grade Crossing: railroad term for intersection of train tracks and
automobile roads. All of the grade crossings on the
Framingham-Worcester line are protected by gates and flashers, and
there are no 'quiet zones' on the line (quiet zones are locations
where trains do not blow their whistles as a warning at grade
crossings). The Framingham-Worcester line has only five grade
crossings over 45 track miles. Listed from east to west:
Bishop Street, Framingham (milepost 20.9)
Concord Street, Framingham (milepost 21.3)
Main Street, Ashland (milepost 24.2)
Cherry Street, Ashland (milepost 24.4)
Parmenter
Lane, North Grafton (milepost 37.4)
In the eastbound direction, the grade crossing at
Concord Street in Framingham is usually manually activated for
commuter rail trains. See "DTMF" above.
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Grade: Hill, slope, change in elevation. Because trains have
limited traction between the wheels and the rails, even a small
grade can be difficult for a train to traverse, especially if the
train has to go up a grade from a standing stop (such as at a
station). See "sand" below.
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Grand Junction: A single track rail line that connects the south side to the
north side, via the Beacon Park freight yard, a bridge over the
Charles River, and tracks that run through Cambridge (close to
MIT). The Grand Junction is used for regular freight service. It
is also used by Keolis / MBTA to reposition trains between the
south side and the north side, especially to get equipment to and
from the BET / CRMF (see above). Amtrak uses it to reposition
equipment from the "Downeaster" service (between North Station and
Maine) and their Southhampton
Street maintenance facility on the south side. There is no
passenger service on the grand junction, so you can't see it on
regular MBTA maps. The Grand Junction is under the jurisdiction of
the Keolis north side terminal dispatcher. You can
see the Grand Junction on this map.
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Head End Power ("HEP"): On a freight train, the locomotive only produces
electricity for the locomotive. There is no electricity
distributed to the freight cars. The brake system on the freight
cars uses compressed air, so there is a hose connection between
each freight car and the locomotive to distribute this compressed
air, but other than the actual couplers holding the train
together, the compressed air hose is the only connection between
freight cars on a freight train. However, on a passenger train,
electricity is needed in each coach (for lights, HVAC, etc.).
Locomotives used for passenger trains, therefore, have a separate
system to provide electricity to the coaches. This system is known
as the head end power. On older locomotives (such as the F40
types), the HEP is an actual separate diesel engine coupled to an
AC (alternating current) generator. On the newer locomotives (the
HSP-46 types), the HEP is just an inverter that takes the DC power
produced by the main engine and converts it to AC. [Actually, the
new HSP-46 locos have 6 inverters. 4 are used to provide AC power
to the traction motors, and 2 are used to provide "HEP" for the
coaches.] The electricity produced by the HEP is distributed
throughout the train via a "MU" (Multiple-Unit) cable (see below)
(passenger coaches also use compressed air for the braking system,
so there is also a compressed air hose connecting each coach and
the locomotive to the coaches).
The HEP system helps to explain some of the
different failure modes of the locomotives. If your train is being
pulled by an older F40 series, then the failure of the HEP system
does not necessarily prevent the locomotive from moving, since the
HEP is separate from the 'prime mover' engine. Likewise, failure
of the prime mover on an F40 does not result in a loss of lights
or HVAC in the coaches. However, for a train with a HSP-46
locomotive, failure of the prime mover diesel engine will disable
everything - the HEP inverter will have no power, and the traction
motors will have no power. But failure of the HEP inverter on a
HSP-46 will not prevent the traction motors from moving the
train.
The one big caveat to this theory is that the HEP
(on both older and newer locomotives) provides electricity for the
control stand in the control coach. So in push mode, where the
train is being operated from the control coach, loss of the HEP
may result in the train being disabled since the engineer will not
be able to operate the controls.
Head end power
Wikipedia article here.
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Heat Restrictions, Heat Kinks, etc.: See this blog post. Then, after you read that blog post, read this one and then this one.
Help Desk: See "Channel" above.
High Ball: Throwback term meaning 'clear signal.' An artifact of the
original way of displaying a clear signal to an oncoming train at
a manually operated signal - literally, a ball raised to the
highest point.
High Car Detector: Similar to a defect detector (see above), this device
detects an overheight
locomotive, freight car, or passenger coach before it can strike a
bridge. Years ago, the bridges on the Framingham - Worcester line
between Worcester and Framingham were upgraded to a higher
clearance primarily for autorack freight cars that were previously
unloaded in the "CP" yard in South Framingham. The Boden Lane
bridge just east of the West Natick station was not raised and is
therefore a height restriction for anything coming east from
Worcester (or points west). A high car detector (with a setting of
17' 2.5") is on an overhead structure in downtown Framingham -
just east of CP 21, right in front of the old Dennison
Manufacturing building. This high car detector is linked to the
flashing white ("lunar") wayside signal lights just west of the
West Natick station. If an overheight car is
detected, the flashing light will turn solid - and an engineer who
sees this must stop the train and then inspect the train to
determine why it is overheight.
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Home Signal: The signal controlling entrance into an interlocking. This
signal can be controlled by the dispatcher (as opposed to
automatic block signals (see above). A home signal typically has
no signs or markings on it (unless it is also a distant signal for
the next interlocking - see "Distant Signal" above). There are
specific rules for a home signal (as opposed to an automatic block
signal) - for example, all red at a home signal is a stop and go
no further while all red at an automatic block signal is "stop and
proceed." See also "NORAC" above.
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Interlocking: A set of signals that are interlocked to prevent erroneous
operation. For example, the signals in an interlocking can be
programmed such that they will not allow 'proceed' or 'clear'
signals to be displayed if switches are misaligned. In common
usage (especially on the Framingham-Worcester line), the term
"interlocking" refers to the physical collection of signals and
switches within each Controlled Point (see CP above), since each
interlocking is a CP, and also has a set of switches. The 'limits'
of the interlocking are the furthest points outside of these
switches, and marked with signals. The switches and the signals at
each interlocking are remotely controlled by the dispatcher (and
also automatically linked to the Automatic Block Signal system).
The Framingham-Worcester line is widely known for having an
insufficient number of interlockings. The number of interlockings was reduced while Conrail was the
operator, in an effort to reduce the complexity and cost of the
line. Also, the frequency of train traffic did not require a large
number of interlockings. More interlockings increase the flexibility of routing
trains.
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K-Car: Kawasaki built double level coach. See "double" above.
Lake Shore Limited: The name of the Amtrak train that serves the Boston to
Chicago route via our Framingham - Worcester line. Wikipedia article
here. Amtrak.com page
here. There is one trip daily (7 days a
week) in each direction. The train provides passenger service stops
at Worcester, Framingham, Back Bay, and South Station, and doesn't
stop at any other stations between Worcester and Boston. It is
possible to buy a ticket between Worcester and Boston, but not
between Worcester and Framingham or Boston and Framingham
(presumably since the MBTA offers Framingham service, Amtrak can't
or won't provide service on that 'commuter' portion). One could buy
a Boston to Worcester ticket and just get off at
Framingham...although this ' hidden city'
ticketing is against the Amtrak rules. A passenger could save
about a half hour by taking the outbound midday Lake Shore Limited
to Framingham or Worcester instead of P517 on the current MBTA
schedule. I've never tried it...
Another interesting note about this train is that
it actually has a "Y" type of route. The eastbound train from
Chicago is actually physically split at Albany with some coaches
(and passengers!) going south to New York City while some coaches
and passengers go east to Boston. Similarly, the westbound train
from Boston meets up with the northbound train from New York City
and joins to become one train set to Chicago from Albany.
This
train is sometimes deridingly called the "LATE Shore Limited," due
to its historically terrible schedule performance. For example, in
the 12 months from October 2014 to September 2015, it was on-time only 38% of the time ( click here for on-time performance metrics). Logically, the westbound departure from Boston
is usually on-time in our area, while the eastbound arrival from
Chicago is more likely to be late (due to the accumulated delays
of the long trip). The schedule as of April 2015 has the
following daily (including weekends) schedule in the Boston area:
Westbound from Boston to Chicago:
Depart South Station: 12:50 PM
Back Bay: 12:57 PM
Framingham: 1:25 PM
Worcester: 2:03 PM
Eastbound from Chicago (via Albany):
Worcester: 6:44 PM
Framingham: 7:12 PM
Back Bay: 7:52 PM
South Station: 8:01 PM
Layover: Overnight 'parking' for a train set on a dedicated siding
where it can be plugged into ground power. At the current time,
the Worcester MBTA yard has capacity to layover 4 train sets. No
trains currently layover in Framingham or anywhere else on the
line. Aerial photo of Worcester layover yard.
Mechanical Help Desk: See "Channel" above.
As long as freight trains are permitted to share
the line with the commuter trains, full high platforms (such as at
South Station and Yawkey)
are less likely, due to the complexity of the required removable
sections. Even at a station like Back Bay, where a full high
platform could be installed, it is unlikely to be installed due to
budgetary constraints.
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MU (Multiple-Unit) Cable: A short cable used to connect the locomotive to
the coaches and the coaches to each other. Spare MU cables can
frequently be seen hanging around the platforms at South Station.
The MU cable is used to transmit electricity from the HEP (see
above) in the locomotive to the coaches. The MU cable also carries
control signals to and from the control stand in the control coach
(or between two locomotives in the case of a multiple locomotive
consist). The sockets where MU cables connect can be seen next to
the coupler on the end of coaches or locomotives. An MU cable is
needed to hook up one train to another, and therefore each train
set is supposed to have a spare MU cable (and air hose) on board
in case connections need to be made 'in the field' (away from the
infrastructure and support of a terminal or maintenance facility,
which would probably have plenty of cables and hoses hanging
around). A missing MU cable (or air hose) from a broken-down train
and its designated rescue train contributed to the delay of a
third train on December 18, 2015. See here for the blog post about that story.
Non-Revenue: Movement of a train set from one place to another, BUT
without passengers. Sometimes also called a "deadhead" move. A
non-revenue move can be a regularly 'scheduled' move with specific
times, but it won't be on the public MBTA schedule (it would be
on
the employee timetable). Non-revenue moves also don't show up on the
GPS tracking apps. Non-revenue moves can also be 'extras' when it is
needed to move equipment from one place to another outside the normal
schedule.
NORAC: Northeast Operating Rules Advisory Committee. A consortium of various railroads developed common operating rules in an effort to improve safety and interoperability. Those rules are commonly known as the "NORAC" rules. The latest edition of the rule book is the 10th edition. The rules govern everything including employee conduct, the meaning of signals, speed limits, and the operation of trains on the railroad. See also Form D above.Wikipedia article here.
Northeast Corridor: Sometimes referred to as just the "Corridor," the Northeast Corridor is the Amtrak train line that stretches from Boston to Washington DC. From Boston to Wickford Junction (RI), the MBTA Providence line shares the route with Amtrak. There are a series of dispatchers (all Amtrak employees) at the South Station CETC (see "CETC" and "Dispatcher" above) responsible for the Northeast Corridor from New Haven, CT to Boston, and those dispatchers handle all traffic on the Corridor including commuter rail, freight, and Amtrak trains. These dispatchers sit in the CETC theatre in South Station - and the dispatch software and computer systems for the Corridor from New Haven CT to Boston are in South Station. An agreement between the MBTA and Amtrak allows Amtrak to use the Massachusetts owned rail line from the Rhode Island border to Boston for free, in exchange for Amtrak providing dispatch and maintenance services for the line. The Corridor has overhead catenary (power lines) for Amtrak trains, including the Acela Express. Along an 11 mile stretch from just north of Mansfield station to just south of Attleboro station, the authorized speed of the Acela is 150 mph. This is one of only a few places the Acela reaches its maximum speed - the fastest speed of any train in the United States. See also "ACSES" above. The Framingham-Worcester line parallels the Corridor from Back Bay to South Station (on the opposite side of the Orange Line tracks). Wikipedia article here.
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North Side: The network of rail lines originating from North Station.
Notch: Unlike a car's accelerator, which can be depressed in a
smooth continuous action, the throttle of a locomotive has eight
notches that correspond to the amount of electrical power applied
to the traction motors (with one being the lowest amount of power
and eight being the highest). Electronics in the locomotive speed
up the prime mover engine to provide increased power as higher
notches are selected. See also Diesel-Electric and Traction Motor.
Old Colony Lines: The Greenbush, Kingston/Plymouth, and Middleboro
commuter rail lines; so called because they were operated by
the Old Colony RR previous to being taken over by the New
Haven system. Largely abandoned in late 1950's and restored in
the 1990's as traffic mitigation for the Big Dig. These are
the newest lines in the commuter rail system, and they are
constructed for high speeds and the stations all have high
level platforms. Because they have all high level platforms,
the coach doors can be remotely operated from a single
position - like a subway car - so passengers can board at any
door, not only one with a conductor standing next to it. Only
some coaches are equipped with these remotely operated
automated doors, and those coaches are identifiable by the
lack of exterior door handles and a yellow 'D' after each
car's road number. Therefore train sets with all automated
doors remain assigned to the Old Colony lines and are not
usually interchanged with the other lines on the south side.
Automated door coaches are sometimes mixed in with other south
side line consists. Old Colony lines do not serve Back
Bay station.
Pax: common Twitter abbreviation for "passengers."
Penalty Brake Application: The automatic application of the brakes by the
locomotive / control coach electronics in response to a
failure by the engineer to respond properly to a signal or
some other operational consideration. For example, if the
engineer exceeds the speed limit for the signal displayed by
the cab signal (see above), the brakes will be applied. A
brake application as a result of not responding to the deadman switch (see above) is also
a penalty brake application. It is called a penalty brake
application not because some kind of disciplinary action is
taken against the engineer but rather because a certain set of
steps must be undertaken by the engineer to release the brakes
and resume normal operations. This may or may not involve the
train coming to a full stop. It should be noted that an
equipment malfunction can also cause a penalty brake
application - for example, if communication is lost between
the fixed 'track-side' cab signal system and the on-board
'train-side' cab signal system, a penalty brake application
could result. The penalty brake application system is designed
to be a redundant safety system. So not all penalty brake
applications are the 'fault' of an engineer.
Plate "X": Various
railroads have differing clearances around their tracks (such as
different bridge heights). In order to allow for a standard
reference among the different railroad companies, the
Association of American Railroads (AAR) adopted a uniform system
of classifying the 'loading gauge' of railcars using the "plate"
system. Rail routes can be designated by the maximum plate
clearance allowed, which allows for easy determination of the
suitability for a railcar over a particular line. All freight
railcars must be marked with their plate letter - some say
"plate x" while some just have the letter. The various plate
dimension diagrams are here. Wikipedia article here.
Positive Train Control (PTC): Another complex (and controversial) topic that
really requires its own page. But oversimplified to a
ridiculous extent, PTC is an automated system that prevents
trains from doing things they shouldn't do. Essentially it is
a backstop in the case of an engineer making a mistake. For
example, if a train (and train line) is equipped with PTC, and
the train were to pass a stop signal, the PTC system would
take control and automatically stop the train. The
Framingham-Worcester line does not yet have this
functionality, although it is mandated (by federal law) to be
installed by 12/31/2018 (for all trains everywhere). The MBTA
has announced plans to comply with this mandate (except the Providence line, which already has ACSES for
PTC (see above)). In late December 2015, the MBTA awarded a
$338 million contract to implement PTC on the entire commuter
rail system.
Press release here.
There is a good news report here about the implementation of PTC on the last section of
the Northeast Corridor that didn't have it - in Philadelphia.
The news report includes
a
demonstration of PTC / ACSES (see above) in the Amtrak
simulator.
PTC Wikipedia article here. Generally speaking, PTC is the highest form of signalling
and train control available. Over history, the progression of
signals and controls went generally like this, from oldest and
least complex to newest and most complex:
1) Track side employees manually changing
flags or some sort of signal at points along the line (see
"High Ball" above)
2) Automatic block signal systems (see above)
3) Cab signals (see above)
4) Positive Train Control
Prime Mover: The engine within the locomotive that produces the energy
needed to run a generator that produces electricity for the
traction motors. All MBTA commuter locomotives have a diesel
engine as the prime mover. See Diesel-Electric above.
Private Varnish: Privately owned rail car, used for chartered (or just the
owner's private) excursions. Private varnish railcars can
occasionally be observed at South Station where they serve as 'hotels' while their passengers
spend the day / weekend in Boston. Assuming they meet certain
Amtrak standards, private varnish railcars are typically towed
by regularly scheduled Amtrak trains from point to point.
Anyone can charter the private varnish railcars that are
available for charter (some are not chartered out by their
owners) - but the cost is not quite within reach for the
average family - see this article. However, there are some opportunities to purchase a single
'berth' / seat / room on private varnish trips. Most are
listed here. The American Association of Private Railroad Car Owners is probably the best source of information -
they publish a magazine about the private varnish 'industry.' Private
varnish Wikipedia
article here.
PTIS: Passenger Train Information System. This is the system that
transmits GPS data from each train back to MBTA / Keolis
Customer Service and also automatically out to all of the apps
and websites we use. It is also linked to the LED sign system
at each station, to the "Rail Radio" system (see below), and
to the on-board train announcements ("next stop is..."). The
on-board PTIS can be manually reset by conductors on the
train, but it is usually automated and does not require the
conductors to do anything (even when a train turns). This is
why trains arriving at South Station start saying silly things
like "the destination of the this train is Readville,"
even
when the train hasn't fully arrived in South Station. That's
the PTIS automatically resetting for the next trip. The
on-board PTIS can also be remotely reset by Keolis
from a central location. The PTIS system is NOT linked to the
dispatch system, so it is NOT used in the formal dispatch /
control system for trains. It is just for gathering
information so Keolis can share that info with
customers (either manually in the case of text / tweet alerts
or automatically in the case of app data). Keolis
actually uses a combination of PTIS data and dispatch
information to generate the text alerts and tweets about
delayed trains. Each control coach (see above) has a PTIS
system - that way each train has one PTIS since most trains
only have one (and only one) control coach.
Push-Pull Mode: In the old days, before control coaches existed, a train
could only operate in one direction. The train would have to
be turned around at each end of its trip to keep the
locomotive in front. Alternatively, a locomotive could be
attached to either end of the train. Both methods are
obviously very inefficient. The control coach solves this
problem by allowing the train to be 'pulled' out of Boston
with the locomotive in the lead and then 'pushed' back to
Boston with the control coach in the lead. Most commuter rail
systems and even Amtrak operate trains in push-pull
mode. Wikipedia article
here.
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QB: Prefix applied to all mileposts along the
Framingham-Worcester line from Boston to Worcester. Actually
the QB mileposts go across the entire former Boston &
Albany line all the way to near Albany, New York. Mileage is
measured from 0 at South Station, but the first mile of track
is within the Northeast Corridor and those mileposts are named
according to that system. The first named / referenced QB
milepost is just west of CP COVE (see Controlled Point above).
When Conrail owned and operated the line, mileposts were
simply referred to as "MP." When Conrail was dissolved and CSX
acquired the Boston & Albany line, the mileposts were
eventually renamed according to a CSX naming convention in
order to avoid the confusion of all train lines having "MP"
mileposts. All former Conrail lines were given the first
letter "Q" and a second letter that usually corresponded to
some historical name of the line - "B" for Boston & Albany
in our case. Hence the "QB" mileposts were born. Details here.
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Rail Radio: Low power AM radio transmitters at some stations that
transmit information about trains to waiting passengers.
It uses data from the PTIS system. More info here.
Passengers do use it - I've seen occasional complaints on
Twitter when it is out-of-service at particular stations.
Readville Switcher: Slang term for the overnight assignment of a work locomotive
to shuttle locomotives and coaches between the Readville
maintenance facility, the South Side Service & Inspection
Facility (near Widett
Circle), South Station, and the BET (see above) via the Grand
Junction. If you are at South Station anytime after the
evening commute, you may see the Readville
Switcher at South Station as it moves equipment around. The Readville
switcher occasionally ventures farther out (primarily to
Middleboro or Rochester) to deliver or retrieve equipment
to/from maintenance and/or storage facilities.
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Restricted Speed: the slowest, most conservative movement that is allowed /
defined by the NORAC rules (see above). Three conditions are
set out in NORAC rule 80 which govern movement at restricted
speed, and paraphrasing / simplifying them:
a) must be able to stop the train within half the
range of vision to avoid an obstruction or problem (so a train
might have to really crawl around a curve if the sight
lines are blocked);
b) maintain a lookout for broken rail and
misaligned track;
c) can't exceed 20 mph outside of an interlocking
or 15 mph within an interlocking (see "interlocking" above).
Riverside:
Most people think of Riverside as the end of the "D" branch of
the green line. However, the entire above grade portion of the
"D" line is just a former big 'loop' off of our Framingham
Worcester line (eventually known as the "Highland Branch."
Before it was used for trolleys, it was a regular rail line.
It started at a switch off of the main line at the location of
the present day Yawkey station. When the "Highland Branch"
was reconfigured to connect to the underground subway system
in downtown Boston, this switch was removed and a tunnel was
extended from Beacon Street to just beyond Miner Street where
the Green line tracks emerge to follow the "Highland Branch"
towards Newton. See this page for a good diagram showing the present day
path of the Green line near Yawkey
station.
The "Highland Branch" rejoined the main line
at a switch very close to the Charles River in Newton. That
switch, now known as the "Riverside" switch, still exists and
is between CP 11 (see Weston Switch below) and the Auburndale
station. The Riverside switch area has been used most recently
as a staging area for the construction crews involved in the
rail destressing project (see Heat Restrictions above). The
Riverside switch is actually a physical connection between the
Green line and the Framingham - Worcester line, and the rules
that regulate "light rail" (Green line) and regular commuter
rail equipment require that the physical connection be
interrupted. Various methods have been used to maintain this
separation over the years, including a pile of sand / gravel,
derailers, and other physical obstacles. A
locked fence gate now separates the Green line from the
Framingham Worcester line at the Riverside switch. The section
of track within the fenced area has overhead catenary
(electric wires) for Green line trolleys. That section of
track leads directly to the Riverside Green line station, and
is sometimes used for training, testing, or storage of
cars. You can see the fenced-in area with the overhead catenary
from the Framingham Worcester main line as you pass by the
Riverside switch. From October 23-25, 1996, a temporary platform
was constructed and used for special commuter rail train service
from Riverside to Boston after heavy flooding at the Fenway
portal closed the entire "D" branch. Here is a great photo of a green line trolley and commuter rail engine on the
same tracks. The Wikipedia article about
the
"D" line includes the entire history of the "Highland Branch."
Riverside was also a station on the Framingham
Worcester line, separate from the Riverside station we know
today on the Green line. You can still see the remnants of the
station if you look closely as the trains pass by the
Riverside switch. Just to the west of the switch on the south
side of the tracks are both a stairway leading down below
grade and a paved platform.
Rotem: See "Double" above.
Rule 241: This rule (see NORAC above) is used to allow a train to pass
a stop signal in conjunction with a radio conversation between
the dispatcher and the train. Use of this rule does not
require issuing a Form D (see above). Note that if a train is
issued permission to pass a stop signal under Rule 241, the
train must proceed at 'restricted speed' (see above) to the
next signal. There are other rules that you may overhear
referred to in radio conversations between the dispatcher and
the engineer or conductor, but this is one of the most common.
Sand:
Grainy stuff that gets in your beer at the beach. Also the
stuff that is stored inside each locomotive and dispensed via
small tubing onto the point of contact between the locomotive
wheels and the rail in order to increase the traction between
the wheels and the rails, especially in the case of autumn
slippery rails or slippery rails due to rain, snow, or ice.
Small piles of sand can sometimes be observed next to the
tracks within stations where too much sand was dispensed. The
sand can be dispensed automatically when the locomotive senses
wheel slip or manually by the engineer. Wikipedia article
here.
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Screamer: Slang term for the older F40PH locomotive type that had no
separate diesel engine to drive the HEP generator (see above).
The HEP generator on these locomotives was driven directly by
gear connected to the prime mover - and because the HEP needed
to be run at a constant speed to generate electricity for the
coaches, the prime mover needed to be run at a (high) constant
speed - hence these locomotives were always 'screaming.' The
last of these locomotives were taken out of service in 2015
when the new HSP46 locomotives were delivered and placed into
service. See the NETransit Roster
for more info on locomotive
inventory.
Set
or Consist:
a combination of a locomotive and coaches that forms a
train.
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Shoo
Fly:
Temporary track installed to provide a detour around
something else (usually to provide access / clear area for a
permanent construction project).
S&I:
Service and Inspection. Usually a reference to the "S&I"
tracks at the Amtrak Southhampton
Street Yard. You may overhear the "Amtrak Terminal"
dispatcher (see "dispatcher" above) talking to a train crew
and sending them to "S&I #3" or "S&I #4," which are
the storage tracks outside the Amtrak service buildings
(S&I #1 and #2 go through the Amtrak S&I maintenance
building). Through an arrangement with Amtrak, Keolis
/ MBTA uses some of the Amtrak tracks at their yard to store
trains during the mid-day hours. It's an obvious solution:
most of the Amtrak fleet is out on the road during the
middle of the day traveling to New York and Washington DC,
leaving those tracks empty and unneeded. But quite a few
MBTA / Keolis
train sets need storage in Boston between the AM rush and
the PM rush. At night, the condition is reversed - Amtrak
trains are being stored in Boston, while the MBTA / Keolis
trains are being stored at distant 'layover' yards awaiting
the AM rush. See this
document for
more about layover and maintenance facilities.
Single:
See "flat" above.
Slippery Rail: A
condition where the rails become slippery in the autumn due to
the breakdown of leaves on the rails. This can cause wheel
slip (see below) or in extreme cases, engine burn (see above).
It can also cause a train to slide past a stop. Slippery rail
can be enough of a problem to prevent a train from starting
from a stop, especially if going up even a slight grade. On
the Framingham-Worcester line, there is a slight uphill grade
leaving the Natick Center station, which can be problematic
during slippery rail season. The stations in Wellesley seem to
be more prone to slippery rail effects, certainly due to the
proximity and abundance of trees near the line. Keolis created acute little cartoon video describing
the
problem and the ' rail washer'
they use to combat / mitigate the slippery rail. Keolis
also published this brochure. Slippery rail Wikipedia article here.
See also "sand" above. People like to chuckle and think
slippery rail must be a joke, just because it sounds so
laughable that leaves could stop trains, but it isn't a joke -
it's a serious, legitimate problem on many railroads around
the world.
South
Side:
The network of rail lines originating from South
Station.
SRO:
Common Twitter abbreviation for "Standing Room Only" - as in
train crowded, all seats taken, passengers standing in aisles.
Starter:
The first signal departing the South Station platforms, at the
far end of each platform (away from the South Station headhouse).
Technically
this is a home signal for the "Tower 1" interlocking. You may
hear the South Station terminal dispatcher tell a train "OK
down to the starter" which means the train can start moving
out of the station since the signal will change momentarily.
Tower
1:
Interlocking (see above) just outside of South Station that
encompasses all the switches that allow trains coming from any
line to go to any platform in South Station. Each line that
comes into South Station has a signal to enter the Tower 1
interlocking, and sometimes due to trains crossing ahead, an
inbound train will be stopped at that signal for a few
minutes. On the Framingham-Worcester line, the inbound
(eastbound) Tower 1 signal is just past where the tracks start
to curve into South Station. The Tower 1 signals on the
Framingham Worcester line are at the same point as the Tower 1
signals on the Northeast Corridor, so trains from Worcester
and Providence are sometimes both stopped at Tower 1 right
next to each other. On Thursday, February 18, 2016, Tower 1 died and caused
enormous problems for all South Side commuters. I explained more
about Tower 1 and what happened in a blog post about the Tower
1 failure.
Adam Gaffin of universalhub.com
posted a couple of fascinating follow-up blog posts about the
history of Tower 1: post 1 here and post 2 here.
Trainmaster:
The Keolis manager responsible for
managing the fleet of commuter rail equipment. These
responsibilities include keeping track of which train sets
have sufficient fuel for their trips or shuffling train sets
in the case of break downs or problems. Conductors or
engineers will confer with the "trainmaster on duty" when they
encounter an issue at South Station and need a management
decision (or assistance resolving a problem). The trainmaster
at South Station sits in the bubble (see above).
Trainman:
See Assistant Conductor above.
Traction Motor: The
actual electric motor that turns the axles connected to the
drive wheels on a locomotive. All modern day locomotives
(freight and passenger) use electric motors to drive the
wheels. Most locomotives have one traction motor for each
drive axle, hence all MBTA locomotives have 4 traction motors,
since they all have four drive axles! The traction motors are
located at the axles, making them very susceptible to
ingesting snow (especially fine powdery snow). Once ingested,
the heat of the motors melts the snow into water, and water
and electric motors is not an ideal combination. See also
Diesel-Electric above.
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Trap:
the movable platform over the set of stairs that allows
passengers to climb onto and off the coach down to a grade
level platform. The trap is left closed when the coach is
aligned with a high level platform so passengers can walk
directly onto or off the coach. Federal Railway Administration
rules require traps and outer doors to be in the closed and
stowed position before a train can be moved. Those rules also
state that only train crew members can operate the traps. Back
in the good old days (prior to maybe 2004?) all the traps and
doors were left open and we passengers could embark and
disembark anywhere we wanted to. While it was convenient, I
observed some slightly scary 'near misses' related to
unsupervised boarding and exiting of trains - lots of people
would get off trains while they were rolling to a stop, since
you could walk right down the steps while the train was still
approaching the station. See also "vestibule" below.
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Turn: the
process of changing one set of equipment from an outbound to
an inbound (or vice versa) train.
Upgrade:
the change in the condition of a signal from a more
restrictive condition to a less restrictive condition. For
example, if an engineer approaching a signal sees it change
from "approach" (similar to a yellow traffic light) to "clear"
(similar to a green traffic light), that would be an
'upgrade.' Since the engineer is required to tell the
conductor the condition of any signal less than clear, using
the term 'upgrade' makes it clear that the signal changed to
something better. See also Automatic Block Signal above.
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Vestibule:
the unheated space at the end of each coach that contains the
trap (see above). As per Federal Railway Administration rules,
it is illegal for a train to be operated with passengers
occupying the vestibules, since the vestibules are designed as
'crumple zones' in the case of a collision.
Wayside Signal: A signal
post / tower / mast on the side of the tracks.
Weston Switch: Dave's
nickname for the set of switches / interlocking at CP 11. See
"interlocking" and "CP" above. CP 11 is in the town of Weston,
alongside Recreation Road and the Leo J. Martin golf course,
just west of Route 128, between Auburndale Station and
Wellesley Farms Station. This interlocking is a critical
element of the Framingham Worcester line because it is the
only set of cross over switches between Framingham and Boston
- therefore It provides the only place where trains can
switch from track 1 to track 2 which might be needed for a
number of reasons:
1)
Provide service to the Newton stations, which only have a
platform on track 2;
2)
Align rush hour trains on track 2 between Wellesley Farms and
Framingham;
3)
Provide a place for the two 'leapfrog' express trains (P582
and P583) to switch onto the other track in order to go around
parallel traffic; and
4)
Provide a place for trains to switch to another track due to a
disabled train (or flooded track, or blocked track, or broken
track, etc.) on one track.
West Station: new
station proposed to be built in conjunction with realignment
of Mass Pike in Allston. See this
blog post and
then read
this one.
Wheel
Slip: The advantage of trains and
railroads is the minimal steel to steel contact between the train
and the rail, which allows for very low friction - hence very good
efficiency (did you see the CSX TV commercial: Moving
one ton of freight 423 miles on one gallon of fuel? And do
you believe
it?). This advantage is also a disadvantage - it can be very
difficult to get a train moving, especially up a hill or with
'slippery rails' (see above). Because there is such low friction,
the locomotive wheels can start to slip and spin - see
this video for an extreme example.
Also notice in that video that you can see the middle axle on
the lead truck of the lead locomotive start to slip at the
beginning of the video - before the ridiculous spinning
sparking wheels. Wheel slip can lead to "engine burn" (see
above) if the locomotive doesn't move enough. Some locomotives
are equipped with automatic limiters which sense slip and
reduce power to the motors. Locomotives are also equipped with
sand to dispense onto the track to increase friction. See
"sand" above.
Wye:
An arrangement of tracks in a "Y" formation that allows for
the direction of a train to be reversed. Similar to a three
point turn in a car.
