Alaska Railroad GP 40 Lights
by Dave Blazejewski

I have a question about the lights on the front of a GP 40. I know the ditch lights and headlights, but are the red lights on the nose called class lights or marker lights? How about the vertical two white lights on the cab? I know those wigwag back-and-forth like the ditch lights when the horn is blown, but I'm not sure what there technically called. Thanks for your help!

The oscillating lights are called Mars lights or Gyralight. The former is a company name and the latter is a brand name made by Pyle National. I am not 100% certain but I believe the ARR's are the latter. As for the nose lights, now they are just marker lights. In the old Train Order days they would have been called class lights. Some railroads such as CP had both. I have an old DRGW nose light that was used only as a marker in recent years but was designed as a class light. It has a little lever with the ability to change the color from white (extra train) to red (rear end marker such as on a helper set) or green (second section).