This week's interlocking walkthrough takes us to the first of the three Jamaica interlockings. While it's the first alphabetically, it just so happens to also be the simplest of the three.
DUNTON interlocking sits to the west of Jamaica, on the Atlantic Branch approach to the Jamaica complex. Below is a diagram of that area, but note that there isn't all that many switches in DUNTON interlocking. Be sure to pay special attention to where the interlocking starts and ends (look for "INT DUNTON" and an arrow). Here's a bird's eye view of the location.
DUNTON gets its name from a very old station that doesn't exist anymore, called Dunton. It was opened in 1869 and closed in November 1939. It sat right around where DUNTON tower is now, to the east of Boland's Landing station and to the west of Jamiaca.
There have been a bunch of different former stations in this immediate area that have gone by a bunch of different names, but only Boland's Landing remains toady.
Like I said earlier, DUNTON is the most basic of the three Jamaica interlockings. HALL is a doozy and JAY is just a madhouse, but DUNTON's not all that bad.
Coming east from Atlantic Terminal, the two Atlantic Branch tracks first exit the Atlantic Avenue tunnels and then proceeds east into DUNTON. The first switch is a crossover that goes from Atlantic Branch 2 to Atlantic Branch 1, so that trains from Atlantic Terminal in Brooklyn can access the lower station tracks at Jamaica, or dart over to the Montauk Branch for the long way into the Jamaica plant.
The two Atlantic Branch tracks then split into four tracks, two eastbound and two westbound. The two eastbound tracks are there to allow the trains to glide easily into the upper station tracks at Jamaica station. Could the same task be accomplished without the need for a second redundant track through the area? Probably. But the second track's always been there, so they might as well use it.
Likewise, the double westbound track merges into one at the same location. The westbound tracks collect trains off the different paths through JAY, the interlocking immediately to the east.
There is also one more switch that branches off Atlantic Branch 3 and connects into the Morris Park lead tracks. If you kept going off on this switch you'd end up merging into the Montauk Branch which eventually turns into tracks 10 and 11 that bypass Jamaica south of the station. This switch isn't used very much at all, but it's there just in case.
All of the other switches in the diagram above are either part of JAY interlocking, or are hand-thrown. All of the switches in the Morris Park Facility right next door or the Richmond Hill Yard a little to the north are hand-thrown and are not controlled from DUNTON interlocking.
DUNTON has the traditional hodgepodge of the various types of position light signals. There are signals on gantries, pedestals, floating magically in mid air, the works.
|DUNTON interlocking, looking west, on a cloudy day.|
The switches were remoted to the JCC on the first weekend of that big Jamaica Cutover outage a couple years ago.
DUNTON tower is now mainly reserved for maintenance workers who will camp out there when necessary. There are also some computers or something like that housed inside the tower building itself that relay information to the switches, but none of the actual switching is done from DUNTON tower anymore.
The nearest interlockings are ENY to the west near East New York station and JAY interlocking, a couple hundred feet to the east further into the Jamaica plant.
That just about wraps up this weeks interlocking walkthrough. When we visit JAY and HALL interlockings in June we'll take a closer look at how Jamaica "works" so brilliantly. But for now, we will press on with FOX interlocking seven short days away.