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First number is the blocking code
0 pure train
1 first alternate
2 second alternate
3 third ... etc.
To qualify as an alternate a block must:
1. arrive at the destination or connection point ahead of schedule
2. be destined for the terminal station of the basic schedule or an intermediate point where there is a high probability of having basic blocks to fill the train carrying the alternate block
3. not cause the basic schedule to be late at destination
4. not result in cars for the basic schedule to be delayed for lack of tonnage.
An alternately blocked train should move from the originating station at least an hour and a half in advance of scheduled departure time for each intermediate stop caused by the addition of an alternate block.
The second number is the section number.
The first group of two letters was the origin and the second group of two letters was the destination. See Origin Destination for these codes.
The last letter is the type of train.
|A B||Loaded Auto Parts|
|H J||Empty Auto Parts|
|E||General Service Empties|
|L||Loaded Unit Trains|
|N||Empty Unit Trains|
|Q||Sugar Beet Empties|
|T C||Trailers and Containers|
|Y Z W V||General Merchandise|
Thus the 01EPWCY
would be the first section of an El Paso to West Colton general merchandise train. It would not have any alternate blocks.
On Oct 13, 1985 the symbol system was revised. The first number is now the section number. The fifth letter (position six) designating the train type was changed. Thus the example above became the 1EPWCM.
|C||Unit Coal Train (Loaded or Empty)|
|G||Unit Grain Train (Loaded or Empty)|
|P||Paper or Unit Potash Train (Loaded or Empty)|
|S||Unit Sulfur Train (Loaded or Empty)|
|U||Other Unit Trains (Loaded or Empty)|
|X||Extra or Drag Trains|
The seventh position is the sequence number. This indicates a particular routing or schedule.
The eighth position is for special information.
|H||High wide or high value|
The last two numbers are the day of the month the train left its initial terminal.