RR Signal Aspect Concordance

RR Signal Aspect Concordance


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RR Signal Aspect Concordance


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Please Kontact the Author for any komments, kritisizmz, and korrekshunz.


Purpose

After working on the signal diagrams, it became obvious that it could not be determined with any ease which of the signal aspects, if any, were consistent (had the same meaning) across roads, which ones were inconsistent, and to what degree this inconsistency existed or exists today. Thus, this aspect concordance was created.

Sort Order

Signals are sorted by color, with a particular sort order based on a "priority" system which I think makes some sense. Number or letter plates carry the lowest priority. Then in order of increasing priority are: a dark arm, red, flashing red, lunar, flashing lunar, yellow, flashing yellow, green, and finally flashing green. The 2nd and 3rd arm of a signal are ranked similarly under the respective color of the top arm.

As an example, a solitary red is the first signal in the list. Next is a single red with a number or letter plate. Next is red over dark, then red over red, then red over flashing red, etc., until all aspects starting with red are exhausted.

For the Nit-Pickers,
or,
Before You Complain ...

These signal drawings are generalized representations. They will not be exact for all railroads. The only meanings conveyed by the diagrams are: 1) the number of signal arms; 2) the color of the light on each arm; 3) the displayed colors' vertical location relative to one another; 4) their status as lit or unlit; 5) the presence or absense of modifying markers (and such markers are shown only on signals where such a modification was effected).

All other meanings that may be implied are hereby disavowed. The list of items which these diagrams are not meant to indicate is at least the following: 1) the shape of the signal face; 2) the number of lamps/lenses on the face plate; 3) the orientation of these lamps/lenses on the signal face; 4) the horizontal alignment of the face plates relative to the mast or to each other [with one exception]; 5) the precise RGB value of the color filter employed; 6) others?

Acknowledgements

Dave Pierson, for "hacking in" (by his own admission) the Boston & Maine aspects, and for much constructive criticism and maintenance of honesty :-).

Aspect RR Aspect Name
many Stop
many,
B&M
Stop-and-proceed
WC Restricted Proceed
CRORStop
SCL Stop-and-proceed
CRORRestricting
C&O
NORAC
Stop
C&O
NORAC
Stop-and-proceed
many Stop
CRORStop-and-Proceed

Note:
Staggered signal arms are significant here.
C&O Stop
many,
B&M
Stop-and-proceed
SOU,WC
RF&P
Restricted Proceed
CRORRestricting
many
B&M
Stop
many Stop-and-proceed
SCL Stop-and-proceed
SCL
CUS
RF&P
NORAC
Restricting
many
B&M
Restricting
SCL Slow Approach
SOU Diverging [Route] Approach Slow
many
B&M
Slow Approach
many
B&M
Slow Clear
SOU Diverging Clear
SOU Diverging [Route Clear,] Approach Limited
SCL
CUS
RF&P
NORAC
Restricting
SCL
RF&P
Restricting
WC Restricting
Restricting
SCL Medium Approach
SOU,WC Diverging Approach
C&O Restricting
many
B&M
Medium Approach
C&O
CUS
Slow Approach
CRORLimited Approach
SCL Medium Advance Approach
C&O Medium Approach
C&O
NORAC pre 19__
SCL
Medium Approach Slow
NORAC Medium Approach Medium
C&O
SCL
Medium Approach Medium
Diverging Approach Diverging
NORAC Medium Approach
SCL Limited Approach
SOU Diverging [Route] Approach Slow
CUS Slow Approach
WC Diverging Advance Approach
SCL Limited Approach
B&M Medium Approach Slow
SOU Diverging [Route] Approach Slow
C&O Limited Approach
CRORSlow to Slow (~= Slow Approach Slow)
CRORSlow to Medium (~= Slow Approach Medium)
CRORSlow to Limited (~= Slow Approach Limited)
many Medium Clear
CUS Slow Clear
SOU Diverging [Route Clear,] Approach Limited
C&O Medium Clear
many,
B&M
Medium Clear
CUS Slow Clear
SOU Diverging [Route Clear,] Approach Limited
CRORMedium to Slow (~= Medium Approach Slow)
[AAR] Limited Clear
CRORMedium to Medium (~= Medium Approach Medium)
CRORMedium to Limited (~= Medium Approach Limited)
many Limited Clear
WC Diverging Clear Approach Diverging
C&O Limited Clear
Limited Clear
CRORLimited to Slow (~= Limited Approach Slow)
CRORLimited to Medium (~= Limited Approach Medium)
CRORLimited to Limited (~= Limited Approach Limited)
WC Restricting
CUS
NORAC
RF&P
SCL
Restricting
RF&P
SCL
Restricting
RF&P
SCL
Restricting
many Approach
C&O
NORAC
Approach
many Approach
C&O Approach
many Approach
many Approach Slow
WC Approach Restricting
SCL
SOU
Advance Approach
C&O
CUS
Approach Slow
WC Approach Diverging
C&O Approach Slow
SOU Advance Approach
B&M,
CUS
Approach Slow
[AAR] Advance Approach
CROR Clear to Slow (~= Approach Slow)
Approach Medium
Approach Diverging
CRORApproach Limited
C&O Approach Medium
Y/G/G [AAR] Approach Limited
Approach Limited
C&O Approach Limited
Approach Limited
many,
B&M
Approach Medium
Approach Diverging
CRORApproach Limited
NORAC Advance Approach
SOU Approach Slow
NORAC Advance Approach
SOU Approach Slow
NORAC Advance Approach
SOU Approach Slow
Clear
C&O Clear
NORAC
Clear
C&O Clear
many
B&M
Clear
CROR Clear to Slow (~= Approach Slow)
CRORClear to Medium (~= Approach Medium)
CRORClear to Limited (~= Approach Limited)
G/Y [AAR] Advance Approach Medium
SCL Advance Approach Medium
NORAC
?NYC
Clear
NORAC
?NYC
Clear
NORAC Cab Speed
NORAC Cab Speed
NORAC Cab Speed


Mark D. Bej, M.D.
bejm@ccfadm.eeg.ccf.org
+216-444-0119
1996.11.15