SCL SD45 Gyralights : LUSENET : ACL and SAL Railroads Historical Society : One Thread

I would like to model a SCL SD45 as it appeared in 1975. I know that 2000-2009 were originally ACL units and the rest were acquired after the merger. All seem to have white and red gyralights (or is it mars lights?) on the cab, but some also had them on the long hood end of the locomotive. Which ones had the lights on the long hood, and how were they used? I assume that they always ran the white one, but what about the red one? Did they both oscillate? THANKS!

-- Chris King (, August 22, 1999


I found a photo of SD45 #2032 taken in 1974 showing the gyralight between the number boards with a white light on top and a red light on bottom. The nose light was, of course, a twin white light. All subsequent photos from the late 1970's through about 1983 shows all white lights (twin white gyralights above and twin sealed white lights on the nose below the cab). Most of the shots after 1983 show the upper light removed and covered with a steel plate.

-Tom Alderman (Marietta, Ga.)

-- Tom Alderman (, August 23, 1999.

All of the SD45s that were originally ACL had Pyle Gyralights on both ends, although I can't ever remember running one of those big "clydesdales" backwards on the point of anything. The ones on the rear protruded (like on both ends of ACL's GP7s), but the one on the front was recessed and occupied the space between the number boards above the windshield. Inside the Gyralight housing, two sealed beams were mounted on a single fixture. Both rotated/gyrated at the same time since they were both set in the same fixture, however only one of the two sealed beams was lit at the same time: either the one behind the clear/white lens, or the one behind the red/emergency lens. Operating rules required that the white signal light be operating whenever the headlight was illuminated on bright. When an emergency application occurred (whether engineer iniated or activated as a result of a parted airhose/ trainline), the red signal light came on and stayed on until normal air pressure was restored. There was also a selector swwitch located on the control stand which not only allowed the engineer to manually operate either one, but there was a toggle switch below it which made it possible to stop and aim the gyrating signal light to use as a backup headlight when the main headlight failed. The trouble with both the Mars Oscellating Light and the Pyle Gyralight was that the eletric motors which caused them to dance wore out, which is why I suspect that the ones on the rear of most SCL units were canabalized for parts and thus disappeared in the late 1970s. When the FRA issued an edict requiring all signal lights to work on locomotives so equipped, they began disappearing from the front of all SCL engines as well. It's a shame. They were replaced by flashing strobe lights which never seemed as effective or visible as the big beam of light that the Oscellating or Gyralights provided.

-- Doug Riddell (, August 23, 1999.

Moderation questions? read the FAQ