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SF Rotating Light - Gyrating Warning Lights


SF Rotating Light



This rotating light (see photos) has a plate on which 2 bulbs (clear and red) bulbs are mounted. The plate has a middle section which is perpendicular to the axis of rotation. On each side of this middle section, the plate is inclined inward. It is on these inclined sections (on either side of the perpendicular middle section), that the bulbs are mounted. There are 3 of slip rings or bands in this unit, one being a common, or ground connection. The other 2 provided for selective energization of either the clear or red bulb.

In conversation, it has been called a Mars, a Pyle, and even a "homemade" light. It was only seen used on the Santa Fe Railroad in the era of the F7s and PAs. (It should be noted that the D&H PAs were repainted SF units). The light is composed of a Delco (GM) motor, a Pyle-National red glass lens over one bulb, and a Pyle ring bulb mount for the clear bulb.

US Pat. 2,446,333 (Mars) shows an oscillating light with a circular beam pattern. This patent describes how the power to the bulb is transferred using slip rings or bands on the shaft.

US Pat. 1,772,499 (RotoRays) shows 3 sealed beams being rotated to produce a circular beam sweep. These patents were in effect at the era in which SF was using their oscillating light. (Patents are good for 20 years)

Mars and Pyle oscillating lights designed for mounting in an F or E unit had a knob attached to a shaft which made possible the lowering of the light for service or bulb replacement. The light used by the Santa Fe did not have this provision. It was secured to the pedestal framework by 4 bolts which held the motor base. The motor supported the whole light system. There was no gearbox in the Santa Fe unit. A 72 volt 1/6 HP motor supplied the torque to spin the bulb plate. The motor had the appearance of a clothes dryer motor (as commented to me). of the type evidently manufactured by the Santa Fe (according to various sources in modeler's publications I have seen in years past).

Kevin V. Bunker
Assistant, Administration and Museum Store- CSRRM


Russell Lee Crump of the Santa Fe Railway Historical & Modeling Society (Eastern Archivist) told me that Richard Scholz rescued ATSF information from a dumpster in Topeka. I contacted Richard. In correspondence with the Kansis State Historical Society and Museum, Blair D.Tarr - Curator, also contacted Richard Scholz and told him of the light information I was looking for. Luckily Richard was able to find documentation explaining the origin of the rotating light in the SF (which light was subsequently found in the D&H PAs).

The following 2 letters reveal that the light was designed by a SF electrician and was used on an experimental test basis from 1954-1958. This was a shop-made rotating headlight. The letter of 12-2-1958 states that no further testing of the light was necessary and that authorization was granted to use this light in all future replacements but not in new applications.


In a letter:

Chicago, October 12, 1954

H.F. Mackey
P.J. Danneberg (mech. supts.)
O.G. Pierson

Regarding test on rotating headlight locomotive 87 lead.

A rotating headlight has been devised by a Santa Fe electrician and applied to locomotive 87 Lead. The rotating light consists of a motor equipped with three externally mounted slip rings and a wing arrangement on which a white and red standard sealed beam lamp is mounted and fastened directly to the shaft. There are no reciprocating parts on this headlight, the only movement in the entire mechanism is the rotation of the motor armature.

All ASDEs observing this device in operation should advise regarding its merit and shall appreciate Messrs. Mackey, Danneberg and Pierson transmitting any comment from Road Foremen and others concerning the effectiveness of this light. Any difficulty encountered in operation of this device should be promptly reported to this office and maintenance terminal.

Please acknowledge receipt.

E.N. Chastain - Gen Supervisor - Diesel Engines

In another letter:

Chicago, December 2, 1958
XF 869.24

V.L. Marlo
P.J. Danneberg
O.G. Pierson (all Mech. Supts.)
A.J. Harman
H.F. Mackey

Please refer to my system letter of June 17, 1957 (not found) above file, concerning shop made rotating headlight.

This is to advise that it is no longer desired to follow the rotating light as test material.

Authority has been granted for the use of this light in all future replacements but not in new application.

It is advised that my system letter of June 17, 1957, with attached wiring sketch be retained in order that proper repairs and maintenance can be made.

M.B. Adams
Supervisor - Diesel Engines




The headlight you write about was an experimental one that was designed by a Santa Fe shop electrician (probably at San Bernardino) and first applied to 87L. The E2s from which the 87L came had a single headlight and shops were to add the Gyralite or similar arrangement. Other letters indicate the F7s were getting Gyralites. I've seen reference to Mars Lights elsewhere.

Apparently the experiment lasted from 10/12/54 to 12/2/58 and no doubt other units that were to have rotating or oscillating headlights applied got this experimental one. However, not all units got them. When I was working in Barstow and San Bernardino (1961-1964) many had Pyle- National ones. The ones that originally had no second headlight got theirs when they went to the backshop for class in the 1950s and 1960s (Passenger units).

As far as drawings are concerned, since this was designed in the shops I see a reference made to a wiring sketch which tells me that if any drawings were made it was done in the apprentice school therefore shop use and was not a full blown engineering drawing. In addition, new units back then applied by the Santa Fe shops on per letter to save costs/time. I don't have drawings I don't have records of which units were all equipped with the experimental light but I suspect it would be on the 6/17/57 letter by Mike Adams - Supervisor of Diesel Engines dated 12/2/58 (above).

Richard E. Scholz



A.S.D.E. (also written as ASDE in above letter--) stands for Assistant Supervisor of Diesel Engines. This was the title given to a diesel maintainer who was called out of a certain home terminal like Argentine or Newton, KS to repair or troubleshoot diesel locomotive problems that occurred while the locomotive was pulling a train. He was on a monthly salary and no longer an hourly union mechanic (electrician or machinist). He was called either by the dispatcher, roundhouse maintenance mechanic, etc., so had to answer to the Mechanical Dept. Supervisor as well as General Supervisor of Diesel Engineers in Chicago. The next promotion for a person with this title would be a foreman job somewhere.


The 87L was rebuilt from a model E2 locomotive by EMD a McCook, IL and came out with a model designation of E8M. Each single E2 locomotive unit that went to EMD came out as a single E8M model unit. The 87L came from Locomotive unit No. 9, for example.


Richard E. Scholz


I had initially contacted the Kansas State Historical Society and Museum for information on this light since BNSF stated that this sort of archive material was held at that location. The museum archivist said they had no information that SF had ever made this rotating light. (They never had received the information, as ATSF was set on disposing of the archive material.) If it was not for the dumpster rescue of the material by Richard Scholz, the origin of this light would have remained a mystery. There was no other source for this information. Now that the connection of information of Richard Scholz has been made with the museum, other aspects of the ATSF may also be revealed. In another correspondence, Richard stated that some of the information on this light came from the estate of an A.S.D.E. who worked out of Newton, KS.


Years ago I saw the D&H PA units when they were still pretty new to D&H. I noted that the Mars Lights were never in the same position - almost as though they were meant to rotate. I clearly saw one tilted at a 45 degree angle.

I don't believe there were any alterations to the Mars Lights when the units arrived D&H and were put into service.

Scott J. Whitney


The SF rotating lights were left in-tact on the PAs when they came from the Santa Fe in 1967 to be used by D&H. They were, however, replaced with 20585 Gyralites (red-white) during their rebuilding at MK in 1974-75. see Gyralite Use page

Bill Kaufman