Mars Signal Lights

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The Mars Signal Light was a warning light developed in 1937 by the Mars Signal Light Company, with the assistance of the Chicago & North Western railroad. The Mars company had already been producing a warning light for fire departments to use on their fire engines, making the emergency movement of fire engines in traffic safer.

The Mars light included a motorized mechanism that moved the light and reflector causing the beam of white light to swing in arcs similar to a figure eight. The intent was to catch the attention of motorists as they approached a grade crossing.

In addition to a white light beam, the Mars light also included a red light beam that was used to warn a train approaching from the opposite direction, that a train was stopped ahead. There was also a version of a Mars light that was used on the rear of a train that displayed only a red light beam, to warn a following train that it was approaching a train that was stopped.

On Union Pacific the use of Mars signal lights began 1946 in response to the successful avoidance of a fatal collision on the Chicago & North Western near Nevada, Iowa, in which the 16-car westbound Los Angeles Challenger had a derailment due to a broken rail, causing an emergency brake application. The engineer immediately turned on the Mars signal light's red emergency light, which was seen by the 11-car eastbound San Francisco Challenger, allowing the eastbound train to safely stop before colliding with seven derailed cars on the westbound train. The red emergency light surely prevented numerous injuries and possible deaths. The incident at Nevada, Iowa, took place on June 29, 1945. (Chicago Tribune, August 19, 1945)

By the time of a November 1946 advertisement in Railway Age magazine for the Mars Signal Light Co., the company stated that 28 railroads were using the company's signal light. Some advertising used the phrase "The Light From Mars" due to the warning light's red color.

Mars Signal Lights on UP

Vertical-Beam Lights

Union Pacific first used a vertical-beam light on its Streamliner passenger trains in 1934-1937 time period to warn motorists at grade crossings that a high-speed train was approaching. The vertical-beam light was meant to reflect off low clouds or fog, illuminating a larger area than a standard headlight. This early light was mounted in the locomotive's headlight enclosure and was known as a "vertical-beam light."

On the earliest turret-cab locomotives (M-10000, M-10001, M-10002), delivered to UP in 1934 and 1936, the vertical beam light was part of the headlight enclosure, and was furnished by Pyle-National.

The following comes from the February 3, 1934 issue of Railway Age magazine, as part of its 13-page article about the new M-10000 train.

The double-beam headlight used on the Union Pacific streamlined train was developed by the Pyle-National Company, Chicago, to conform to requirements of the railroad. It comprises both horizontal and vertical light beams, the horizontal headlight performing the normal functions of a locomotive headlight, and the vertical headlight serving as a distinctive marker.

The vertical marker beam will be seen plainly from a distance, and serve to herald the approach of this unusually high-speed unit from a great distance, and more definitely than would be the case with the standard horizontal headlight alone. The vertical beam will be visible off to the sides of the right of way, while the horizontal beam is confined to a comparatively small area forward.

The vertical headlight has a 10-in. silvered glass reflector, and the horizontal headlight a 12-in. reflector of the same type. Both headlights use special 75-volt lamps, the upright light having a 100-watt lamp and the forward light a 250-watt lamp.

The four new UP streamliner locomotives with automobile styling delivered in 1936, numbered as M-10003, M-10004, M-10005, and M-10006 were all initially equipped with a "vertical-beam" signal light that shined upwards. These locomotives were equipped with a larger headlight mounted on the leading edge of their nose, and the vertical-beam light was mounted on the roof, above the center post between the two front windows.

(M-10004 later became LA-4, and was rebuilt in 1939 as the CD-06C cabless booster unit)

(M-10003 became CD-07; M-10005 became CD-05; M-10006 became CD-06, all in 1939)

On its folio diagram sheet for the City of Denver locomotives (S-32; updated to 2-15-43), Union Pacific called this original signal light the "Vertical Beam Light."

The two EMC E2 locomotives, delivered as LA-1 and SF-1, were each equipped with a vertical-beam light. The Railway Age of December 18, 1937, reported that each locomotive was equipped with "a special d.c. driven, a.c. output, motor-generator set. This generator delivers 32 volts alternating current for the illumination of the vertical-beam headlight distinctive to all Union Pacific Diesel locomotives."

(Research using photos of these two locomotives, in which the roof is visible, finds no evidence of a rooftop light and does not support the above report in Railway Age.)

(At some point after mid-1947, and before mid-1948, when each of the two E2 locomotives were sold to SP (SF-1) and C&NW (LA-1), each had been equipped with a Mars signal light installed in the nose in place of the headlight, and the headlight moved lower on the nose below the Mars signal light.)

The EMC E3 (LA-5) delivered in 1939 was equipped with a vertical-beam signal light.

Mars Lights Replaced Vertical-Beam Lights

The rooftop vertical-beam lights on the City of Denver units were replaced in 1946 by a large Mars signal light facing forward, mounted in a large enclosure on the roof.

Within a year, these roof-mounted Mars lights were moved down to a new location on the locomotive nose, below the headlight. Moving the Mars light from the roof, down to the front of the nose may have been in response to the need for access to maintain or repair the internal workings of the Mars light, which would have been difficult in the roof-top location. Also, the crews possibly found the light shining on the top of the large nose to be distracting and unsafe, since the light was only on when approaching a grade crossing (white) or in an emergency (red).

On its folio diagram sheet for the City of Denver locomotives (CD-05-AB, ex S-32; updated to 12-31-46), UP called the nose-mounted light, the ""Mars Signal Light White & Red 480 Watt."

"Originally the COD units were equipped with a vertical headlight as well as the usual horizontal one. When the Mars oscillating headlight was developed, they were initially installed on the cab roofs in the interest of greater visibility. (The vertical ones were removed.) Fortunately the Mars lights were later moved down between the grilles on the prow of the units, below the regular headlight. In this location they did not spoil the sleek graceful lines of these handsome units. These Mars lights were of 480 watt capacity and housed both white and red lamps." (Kratville, Union Pacific Streamliners, page 140)

The roof-top, facing forward position only lasted about a year (1946-1947), at which time the signal lights were moved to the nose of the locomotives below the headlight. When the locomotives were retired and scrapped in 1953, the signal lights were in this later location.

A review of dated photographs suggests that UP applied Mars signal lights to the nose of the COD Streamliner units between May and September 1946, at the same time as they installed similar Mars lights on the 4-8-4 800-class Northerns, along with smaller versions on the Alco PA passenger diesels.

CD-07 (ex M-10003) had its nose-mounted light by July 1949

The model of Mars Signal light used on UP's diesel locomotives was the Model WR-5000. The version used the FEF-class steam locomotives was the Model R-250 (18 inches diameter).

A review of an index of engineering drawings shows the following drawings and the dates they were created:

UP Timeline

1939 -- EMC E3 was delivered as UP LA-5, without a signal light, but received a Mars signal light mounted to the nose above the regular white headlight in the 1948-1949 period.

1940-1941 -- EMD E6s (8 units); two units, LA-4 and SF-4 were delivered with Mars signal lights; six units (7M, 8M, 9M) were delivered without signal lights, but each received a Mars signal light mounted to the nose above the regular white headlight in the 1948-1949 period.

"These [E6s, LA-4 and SF-4] were the first cab units delivered to the Road with built-in Mars oscillating headlights." (Kratville, Union Pacific Streamliners, page 228)

(June 1945 -- Collision of "Los Angeles Challenger" and "San Francisco Challenger" at Nevada, Iowa, prevented by C&NW's use of the Mars signal light.)

1945-1948 -- Fairbanks-Morse Erie-built locomotives were delivered with Mars signal lights. The first, UP 50M, was delivered in December 1945.

1946 -- EMD E7s (7 units) were delivered with Mars signal lights.

"By September, 1946 all regular passenger units were equipped with either oscillating or gyrating headlights." (Kratville, Union Pacific Streamliners, page 228)

1950-1953 -- EMD E8s, numbered as UP 925-942, were delivered with Mars signal lights.

1954 -- EMD E9s, numbered as UP 943-947 were delivered without signal lights.

1955-1963 -- EMD E9s numbered as UP 948-962 (1955), and UP 900-914 (1956-1963) were delivered without signal lights.

On Union Pacific, the rule covering when to use the red signal light did not appear in the operating rule book until 1954. But research suggests that the original change in rules likely came in the form of a Superintendent's Bulletin, distributed to all operating officers and operating personnel. But the date of such bulletin is not yet known.

Mars Signal Lights

May 15, 1937
"New Headlight on "400" -- A new type headlight, which casts a gyrating beam of light in the shape of a figure eight, is being given its initial tests on the '400' of the Chicago & North Western, operating between Chicago and the Twin Cities. The new light, known as the Mars light, is of 3,000,000 candle power, and its reflector is oscillated by a motor which causes the beam to swing in arcs similar to a figure eight. The field of gyration of this figure eight is about 800 ft. in diameter at a distance of 1,000 ft., and precedes the locomotive a distance of 1,400 to 2,000 ft. The light is canary yellow in color and in yard tests it has been observed at a distance of three miles. The light itself is located on the top of the smoke box directly in front of the stack, which places it directly above the regular headlight. The light is expected to be of value as a warning signal when a train approaches crossings." (Railway Age, May 15, 1937, Vol 102 Issue 20, p838)

January 27, 1945
The following comes from the January 27, 1945 issue of Railway Age magazine.

Distress and Warning Lights for Trains -- Several lights for use by trains which have been derailed, stopped unexpectedly or for signaling to approaching trains have been developed by the Mars Signal Light Co., Chicago, Ill. One of these lights, designated WR-5000, for use on high-speed. passenger trains, produces a 500,000 candle-power beam of white light which oscillates in the form of a horizontal figure eight and which can be changed to a red beam when necessary. The white light serves as a warning at grade crossings and the red one may be used by the engineer in the case of an emergency which may obstruct the opposite main track. The second headlight, available for locomotives other than high speed which do not require the white light, is made up with a red beam projector only. A third lighting unit for protecting the rear end of trains produces a powerful red beam which does not oscillate.

The headlight for high speed trains has two fixed outer reflectors and a movable 10-in. parabola reflector in which is mounted a 40-amp., 12-volt lamp. There are two such reflectors placed at an angle of 90 deg., one having a real lens for use as a distress or warning light. The reflectors are caused to oscillate by a 40-watt, 12-volt, 6,000 r.p.m. motor which is reduced to 8 r.p.m. on the oscillator shaft by a reduction gear. The control switch allows for bright, dim, and emergency red positions. There is also a push button switch for inching the light to a fixed position such as for use on curves.

The headlight for use on freight or lower speed trains employs a standard 250-watt, 32-volt locomotive headlight lamp in a 12-in. parabolic reflector. It produces a 350,000 candle-power red oscillating beam. The driving motor is rated 84 watts and 32 volts. The lights are furnished with pressed steel cases for use on Diesel-electric locomotives and for steam locomotives a cast aluminum case is used. (Railway Age, January 27, 1945, Vol 118 Issue 4, p240)

December 22, 1945
The following comes from the December 22, 1945 issue of Railway Age magazine.

Emergency Stop Warning Light -- A railroad safety development involving instantaneous and automatic operation of powerful figure-eight oscillating red lights at both the head and rear ends of trains making emergency stops has been developed by the Chicago & North Western, working in conjunction with the Mars Signal Light Company, Chicago. The purpose of the new development is to protect trains making emergency stops from rear-end collisions or, in the event of a derailment, from being sidewiped by trains on other tracks. The automatic operation of the lights involves a new principal of utilizing the sudden release of air brake pressure. They are so hooked up, however, that the engineman or flagman may also operate them by means of a switch.

Should a train with this equipment come to an emergency stop, either because the engineman has set the brakes or because the air hose between any of the cars has parted, oscillating red lights at both the head and the rear ends of the train will go into operation automatically. The powerful beams will serve as "stop" warnings to all other trains approaching from either direction. On clear nights, the red lights will be visible for several miles and have considerable penetrative power in rain or fog. They can also be seen over a long range in daylight. Obviously, the rear light does not take the place of the flagman who is required to perform his usual duties. The oscillating lights simply provide an additional
safety feature.

New equipment of the type described already has been installed and tested on the streamliner Twin Cities '400' with high satisfactory results. It is the fourth successful step in railroad safety research accomplished by the two organizations mentioned in the last ten years. The first came in 1936 when the Mars oscillating headlight, now a regular feature on many of the nation's fast trains, was developed and placed in operation on the original steam-powered '400.' In July, 1944, the railroad announced the second development - an oscillating headlight that would flash either a red or white light, whichever the locomotive engineman desired. In January of this year came the development of a portable red oscillating light for the rear of trains, preceding the latest innovation of automatic operation by less than a year. The North Western was the first railroad to adopt all of these innovations for its trains.

Method of Operation

The light on the '400' Diesel locomotive is a combination oscillating red-white light. The light on the observation car is an oscillating Mars red signal light only. The automatic feature of these lights is controlled through air-connected switches cut into the brake pipe:

One located on the Diesel locomotive to control the red-white light on the locomotive and one located on the rear end of the observation car to control the red light.

The automatic feature of these lights assures that, whenever the brake-pipe pressure drops below approximately 30 lb. for any reason with the Mars light operating, the light will revolve from white-oscillating to red-oscillating and immediately shut off the regular white headlight. When the pressure of the brake-pipe is pumped up above approximately 43 lb., the red light will turn out and automatically revolve back to white-oscillating, the regular headlight again lighting.

When operating by day with the Mars oscillating light not in use and all switches except the automatic switch in 'off' position, if for any reason the brake-pipe pressure should drop below approximately 30 lb., the Mars light will turn to red-oscillating and remain in this position until the brake-pipe is again pumped up above approximately 43 lb.

The Mars oscillating light on the rear of the train shows red position only and will operate the same as the one on the locomotive. Any time the brake-pipe pressure is reduced below approximately 30 lb., this light will start to operate and automatically shut off when the brake-pipe is again pumped up above approximately 43 lb. The automatic feature of this light in no way interferes with the regular manual operation.

The air switches are of the diaphragm type. Whenever the brake-pipe pressure is above the predetermined upper setting, the contacts on this switch are held open and the Mars oscillating white light is in operation. When brake-pipe air pressure drops to the low limit, the contacts of the air switch close, energizing the polarity-change relay, and the rotating motor will turn the barrel of the Mars light from white to red, at the same time energizing the power cutoff relay to the standard stationary headlight, turning this light out.

At all times when the red-oscillating light is in operation there is no other light displayed to an approaching train. When brake-pipe pressure is again built up to the upper setting, the operation is reversed. The red-oscillating light on the rear of the train shows whenever the red-oscillating locomotive light is operating.

The combination red-white light on the locomotive receives its power from a 64-volt battery through a 12-volt motor-generator set. The lamps used on the red and white positions are 480-watt, 12-volt, bi-post type. The red light on the rear end is a 250-watt, 32-volt standard headlight lamp, taking its power from the car battery.

Mars Signal Lights Patents

Jeremiah D. Kennelly was president of the Mars Signal Light Company, with headquarters in Oak Park, Illinois, a suburb of Chicago. Mars Signal Light Company began operations in Chicago in 1925 as a manufacturer of sirens.

"The Mars Signal Light Company began operations in Chicago in 1925 as a manufacturer of sirens. The firm was organized by the Mars Candy Company, therefore the derivation of the name, Mars Signal Light. The firm installed the first moving light on a Chicago fire truck in 1929, invented the first rotating beacon in 1947, and pioneered the development of the first oscillating safety light for railroads. They also initiated the use of sealed beam lights for standard locomotive headlights. Mars sirens for military use were adopted by the military during World War II. In 1973, the company moved its operations from Chicago to Naples. In addition to sirens, the company has developed and perfected signal lights for emergency vehicles such as police cruisers, ambulances, fire fighting apparatus and others. Currently, there are 21 persons employed." (Naples Daily News, April 24, 1983)

"The first light from MARS was manufactured in 1929 and patented in 1930. This was the first moving signal light. The first manufacturing venture into the signal light field by MARS was made by the MARS Candy Company, believe it or not." (Naples [Florida] Daily News, May 20, 1973)

"Named for His Backers -- Former Oak Park Policeman Jeremiah Kennelly made his first figure eight light a few years before the swift diesel streamliners caused railroads to look for oscillating signals. The initial product was a moving signal for use on fire, police, and emergency vehicles. The company was named after the late Franklin C. and Ethel V. Mars, friends and financial backers of Kennelly, and the first light was made in the candy company's machine shop. In 1934 Kennelly turned out a railway crossing light. A year later his first figure eight for locomotives was mounted on a North Western 400. In addition to these products, the company now makes stationary locomotive lights, moving rear train signals, controls for railway signal lights, and sirens." (Chicago Tribune, January 13, 1952)

(View the many signal light patents held by Jeremiah Kennelly)

In June 1949, the Mars Signal Light company sued the Pyle-National company for stealing its designs in order to offer its own similar signal light. (Chicago Tribune, June 23, 1949)

The Mars light operated in a figure-8 pattern. In later years, Pyle-National offered its Gyra-Light, which operated in an ellipse pattern.

Jeremiah Kennelly died in 1969, at age 69. Upon Kennelly' death in 1969, the company was sold to Oliver Burland, and the company remained as a Burland family-owned business well into the 1980s, after its move to Naples, Florida in 1973.

In May 1973 the Mars Signal Light company announced that it was moving its headquarters and production facilities from Chicago to Naples, Florida. At the time the company's major products were light bars and sirens for police and fire vehicles. The new factory was to be ready in September 1973, but production by 22 employees began in early June 1974. (Naples [Florida] Daily News, May 20, 1973; Naples Daily News, July 7, 1974)

In 1983 the Mars Signal Light company was sold to Sight and Sound Enterprises, Inc., with the Mars Signal Light name being retained. In March 1987 the company was sold to Universal Energy Systems, Inc., of Dayton, Ohio. At the time of the sale in 1987 the company employed only 10 people. Upon her death in 1989 at age 86, it was reported that Edna Burland was one of the founders of the company in Chicago in 1929. Her son, Oliver Burland, passed away 11 years later in March 2000 at age 74.

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