Wednesday, February 14, 2018

Saying Goodbye to Searchlight Signals

Mike Matalis,2009
By the time I started taking pictures of railroads, BNSF/CB&Q had already updated the signals in Downers Grove so I can't easily get pictures of the searchlight heads that CB&Q used for decades. Fortunately, Mike has lots of pictures before they switched to the new signals on March 28-30 2014. This photo shows the signals just west of Forest Avenue in Downers Grove. Downers Grove used to be a terminus for some of the commuter trains. The microwave tower that you see on the right is where the turntable used to be to turn the engines. And west of there was a coach yard. In Mike's photo you can see some of the crossovers that allowed access from all three main tracks to the yard. The crossovers and signals were controlled by Tower R on the south side of the tracks, which is out-of-frame to the left in this picture. You can see it peaking out behind a tree in the photo below.
20140607 0007
Those crossover switches had been removed by June, 2014. Note that the replacement signal is much less complicated. It has just the diverging route off of M1 (right-most or north main) into the yard lead. Also note that the old signal bridge leaves a lot of space to the left of M3. That is because there used to be a track that went south of the station and branched into team tracks and industrial spurs. The currently vacant bank property south of the tracks and west of Forest used to have a couple of industries with railroad spurs. The signal update program to meet the federally mandated implementation of Positive Train Control by the end of 2015 is erasing all evidence of the old tracks. (Update 2017: an apartment building is being built on the vacant land. And the deadline for PTC has been extended.)

Between the lamp housing and the lens of a searchlight is a spectacle. The spectacle is a turret that contains three colored roundels. The red roundel is in the middle and the green and yellow roundels are on either side of the red. The reason the red is in the middle is so red is the default aspect if the control electricity for the head is lost. This provides the fail safe feature that the most restrictive aspect will display if control is lost. A signal head uses either two pairs of lens or a single Fresnel lens. [RailroadSignals]

Robert J Della-Pietra posted a photo of some CB&Q searchlights in Naperville, IL in the fog. The fog shows the light is focused into a tight beam aimed at the engineers eyes. I've noticed when looking at the searchlights from a crossing that if I'm not close to the track, I can't see the light. That is another indication of how small the beam of light is. The reason for the tight beam is so that a low wattage bulb can be used since the bulb's output is concentrated on the engineer's eye. The use of a low wattage bulb is important in wilderness locations such as the mountains where the signals are powered by batteries.

1939 Aerial Photo from ILHAP
According to a Facebook comment, the Naperville signals in Robert's photo were removed in November, 2010. Again, notice the extra width under the bridge. Looking at an aerial photo, it appears there was a lead that went to a freight house and maybe a team track across the mainline from the passenger station. And there was also a lead on the south side of the mainline that went to the lumberyard part of a hardware store that is now a children's museum. I remember going to that lumberyard in the 1970s when we were doing home remodeling. Hardware stores and lumber yards have become as rare as industrial sidings around here. Back in the 1970s, there were six hardware stores and two lumber stores within a couple of miles of our home. Now ACE is the only store left. We now have to drive a lot further to a Home Depot, and it does not have the selection that the hardware stores had. Nor the classic "hardware store smell" that Mochels had.

Mike Matalis has photos during the transition at HinsdaleWestmont, Fairview, and Main.

Mike Matalis caught them taking down the old signal bride west of Fairview Avenue on 3/30/14. During the weekend of the cut over from the old to new signals, they did not remove the bridge, just the heads. As you can see in the "20140607 0007" photo above, the old bridge and shafts were left after the cut over near Forest Avenue. In these older pictures, note the line of "telephone poles" along the north side of the tracks. They are  called "code lines" and they carry the analogue currents that control the signals, switches, and crossing gates. They also carry information from sensors such as track circuits, hot box detectors, dragging equipment detectors, etc. You will see in the more recent pictures that they have been removed along with the old signal bridges and searchlights because the new signaling equipment uses digital information carried on buried fiber optic cables.

Mike Matalis caught them taking down the old signal bride west of Forest Avenue on 10/5/14. Note that the code line along the north side of the tracks is long gone. And he captured the old and new equipment at Westmont.

BNSF (source)
As per the federal mandate, BNSF has installed the PTC infrastructure on all 88 required subdivisions, covering more than 11,500 route miles and 80 percent of our freight volume. We are running hundreds of trains daily with PTC as we test operating in revenue service across our entire mandated territory.

Marty Bernard has a photo that shows Westmont had more code lines than Downers Grove did.

At the end of 2017, they removed the insulated joints that used to support the old signalling system.


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