The former New Haven RR main line is operated by Metro North Commuter Railroad, which, unlike is sister Long Island Railroad (this is also operated under the umbrella Metropolitan Transportation Authority), chose to ruin two of the most interesting stretches of classic signaling in the country by replacing forests of searchlights on overhead gantries with a waysideless CSS with 3-aspect dwarf signals at interlockings.
Ironically Metro North did a fairly good job of preserving all of the closed interlocking towers. One of these, SS44 in South Norwalk, was of the brick walled mechanical variety and after being boarded up was eventually sold to a preservation group in the mid-90's who painstakingly restored the tower as a museum. It is probably the only preserved tower with a substantial mechanical lever frame in North America, and a must visit for signal enthusiast visiting the New York City area. Here is a front view of SS44 taken from a passing train.
The museum makes most of its money be selling a truly excellent book about itself, so if you want any further information put and order in and help support the museum.
Signaling Station #44 was built around in 1896 before the "classic style" New Haven tower design came into effect with the pioneering overhead AC electrification project of 1906 and second phase of 1918. These later towers are square, cast concrete with or without brick and a hipped tile roof. Here are some examples.
While the square footprint NH "standard" towers were designed to take all power frames or electro-mechanical frames with lever operated points and miniature lever operated signals, the narrow rectangular SS44 had a 68 lever all mechanical frame made by the Johnson signal corporation. A more accurate term for this frame might be electro-enhanced mechanical as like later E-M frames, like the US&S style S, all the signals are power operated and governed by both track relay logic and mechanical interlocking logic. The frame was well organized with the red signal levers placed at either end sandwiching the blue and black point and FPL levers. All signal for eastward moves were on the west side of the frame and westward moves were on the east side of the frame.
The lever frame has been fully restored and disconnected from the electric-locking so that one can fully exercise the mechanical locking setting up routes and displaying signals. Unlike British practice all of the points are equipped with facing point locks because trains could operate against the current of traffic under train orders on a fairly regular basis. There almost seem to be more locks than point levers!
With all of the FPL's setting a route for a Danbury shuttle train to cross all 4 mainline tracks required an exhausting 16 lever operations, and I wasn't even having to actually bend the iron!!
SS44 was located at the junction of the Danbury Branch with the New Haven Main Line controlling a facing point ladder onto the branch along with crossover supporting the Norwalk Station complex which handled both main line intercity and commuter trains in addition to terminating Danbury Shuttles.SS44 also had a symbiotic relationship with the adjacent SS45 WALK movable bridge about 1/4 mile to the east and had to handle movements in and out of the west end of the Norwalk station 1/2 mile to the west. The (South) Norwalk station consisted of two side platforms serving the outer trains as well as two stub tracks for the Danbury shuttle trains. Trains on the center trains could make stops be means of crossovers at either end of the platform. West end points were power operated, but the lever numbering was unified with the main plant with signal levers 3,4,7,8 and 9 logically opposing 56,57,58 and60.
And main plant including the SS45 WALK bridge. The interesting symbiosis with SS45 is evident here. SS44's lever 54 was required to unlock the bridge and SS44 signals 68 and 67 were also operated on SS45s frame requiring both sets of levers to be pulled up. SS44 also operated the west derails to protect the movable bridge (the Danbury Branch switch 48 served as the derail on track 3). On the other hand SS44 did not have westbound reverse direction signals on tracks 2 and 4, relying on SS45's instead. SS45 could in theory clear a signal leading to open derails on track 2 ad 4 unless some sort of electric point detection was piped into the SS45 machine.
Signals were original of the suspended stub-semaphore type as discussed in this earlier thread. I do not know if they were changed to searchlight type signals before the tower was closed and control transferred to the NX machine in the new WALK tower, which was then eventually closed in the 1990s.
All tracks were single direction Rule 251, with the Danbury Branch being train order manual block. SS44's #15 lever was in fact a non-interlocked mechanically worked manual block semaphore signal for trains entering the branch. If displaying a Clear Block trains would not have to stop for train orders, however most did, requiring the operator to run down, hoop them up, then run back to throw the 16 levers to clear the track for mainline moves All tracks had controlled approach signals in the main direction. There was one lever per signal and no call-on levers for the ground mounted subsidiary signals. Also per eventual British practice the New Haven used Y/Y for Advance Approach.
I mentioned before that this frame was designed with electric locking in mind. In the locking room you can see all of the electric locking for the mechanical levers. Other frames from this period typically have the electric locking as an almost bolt on option, but here you can see they are fully integrated.
All of the electric locking has been disabled so museum guests can play with the mechanical locking. Speaking of which the mechanical locking is visible below the lever bases which themselves are below the lever room floor. These connect in front to the contact spindles shown above and in back to the mechanical locking grid.
Here we see the vertically arranged locking bed located right behind the electric locks. The pipeline connections are then arrayed between the grid and the wall. For those unfamiliar with mechanical locking the unlocking catch that one squeezes against the main lever to free it for movement is actually what "checks" the mechanical locking. The big heavy levers are attached directly to the pipes and not the locking grid.
The final component of the lever room is this 1918 vintage power board to control breakers for the overhead catenary. The 11Kv 25Hz system was powered from the New Haven's own power plant in Cos Cob, CT. Built in 1906, by 1986 the plant was so run down and so insufficient trains needed to make special stops so that there would be enough power for others to move. The voltage drop was so severe out by New Haven that sometimes train air compressors would shut down. The old plant was closed about the same time the towers were taken out of service and replaced with a 60Hz grid supply.
The SoNoToMu is still located about 5 feet from the electrified tracks and allows open window photography of the passing Metro North and Amtrak action. Here a leased Amtrak P40 heads up an MNRR Danbury shuttle.
And an Amtrak corridor train wrong-rails it on track 1.
These photos were taken in two groups. The first set on a visit in 2008 and a second set on a visit in 2012. I am sure I could have gone into all sorts of details about the tower's operation, but without proper accompanying photos it would just end up as a wall of text. If you are interested in all the nitty gritty details on train order operation and running trains once again I highly recommend buying the book.