Locomotive headlights

[DET63]

Some Amtrak and freight locomotives have horizontally arranged headlights, while the lights on others are stacked vertically. Some headlights are placed on the nose of the locomotive, while others are high-mounted, centered above the windshield. Is there any particular rationale for using one arrangement or location as opposed to another?

I would think that, especially in terms of visibility, high-mounted headlights would be preferable to those only a little higher than the ditch lights. OTOH, on locomotives with a low nose (as most diesels are), would high-mounted headlights tend to shine on the nose itself, possibly creating a distraction for the crew, or are they always adjusted to cast their beam far enough down the track for that not to be an issue?

Also, didn't trains that had Mars lights or Gyralights have one headlight or set of lights on the nose, with the other mounted further up? (I believe the moving light would have been the one mounted higher.)

On double-decker cab-cars, used when a commuter or other push-pull train is pushed "backwards," is it customary to locate the headlights above or below the door (assuming the car has an end door)? It seems to me that the Amtrak California cab-cars have their headlights below the door (perhaps a strobe light is placed above the door, though).

 

[PetalumaLoco]

(2) strobes in bottom, (1) steady below door.

 

[Ryan]

It's all driven by FRA rules. Ditch lights are required now for visibility, in times past I think that strobes/gyralights were acceptable.

I'm not up on all the details, but this should give you a place to start researching.

 

[battalion51]

The location of headlights, number boards, and items of the like are able to be customized generally to the specs of each railroad. For example with a freight engine like the ES44DC railroads have the ability to have high mounted headlight or low mounted, and high mounted number boards or low mounted. So for the longest time CSX went with a low/low combo, NS went high/high, Conrail went high/low, BNSF went low/high, etc. But then CSX changed its mind with late orders for the ES44AC and went to a low/high style similar to BNSF. There really is a negligible difference as far as visibility is concerned, the way the headlights are aimed is what makes the biggest difference.

As far as cab cars go height, practicality, and ability to locate electronics has a lot to do with it. For example on a California Car there's no place to put the headlights above the end door, necessitating their placement below the door. But on a Bombardier Cab Car or Kawasaki Cab Car the door is so low that you have to go above the door in order to achieve the necessary height.

I'm sure somewhere in the FRA rules there is a height that your ditch lights have to be under, since the intent after all is to make the train more visible to folks in cars. Put them up too high and the purpose is defeated.

 

[tp49]

The ditch lights weren't strobe lights they're regular headlights with an alternating flick.

 

[Ryan]

They need to be greater than 36" above the top of the rail - no maximum height (although they have to be either 36" or 60" below the headlights, so there are some practical limitations).

More than you ever wanted to know about lighting on trains:

http://www.trainweb.org/gyra/dc_lts.htm