<<Are you speaking of MARKERS (rear end) or CLASSIFICATION LIGHTS...on the engine..Big difference but often confused >>
Pete raises an important distinction here.
Class lights/flags
Class lights/flags are displayed by the engine to which orders for the train have been issued. The class lights/flags, as previously discussed, define the train’s class as scheduled, extra section of scheduled, or extra.
A scheduled train with no additional sections will have no class lights/flags.
When multiple trains run as sections of the same schedule, all sections except the last will display green class lights/flags. The last section will have no class lights.
An extra will display white class lights/flags. Note that the lights flags should be displayed on the engine which has been used to identify the extra, for example, X 1234 West. Normally, the orders creating and identifying the extra refer to the lead engine in the consist. However, the engine referred to when creating the extra can be anywhere in the consist at the front of the train, _it’s class lights/flags will be displayed, while the engine on the point will carry no flags/lights. This could occur from time to time under various circumstances, including the engine intended to be the lead engine getting “buried” in the consist instead of at the head of the consist. Since the orders creating the extra had been created and distributed hours ago, and subsequent orders already written might refer to the extra as created under the original orders, it was easier to use the class lights/flags on the original engine than it was to take the time at the originating terminal to reshuffle the engines so that the identifying engine was the lead engine.
Markers
Markers denote the end of the train. On a freight they were hung on the caboose. On a passenger train they are displayed on the last car on a train. If you met a train, and looked back at the rear of the tain after you passed it and did not see markers, you should have been very, very careful, because somewhere out in the dark ahead of you is a caboose with one of more freight cars just waiting for you to run into them.
On a moving train, typically, red markers were displayed to the rear, with various colors displayed to the sides. When a train moved off the main, into a siding to allow a train to pass, the colors displayed to the rear and side were changed to indicate that the train was clear of the main.
Best regards,
Steve
Steve Haas
Snoqualmie, WA