Irish Chieftain wrote:In the New Haven Railroad days, the FL-9's could run on electric in both Penn Station with the over running third rail and Grand Central Terminal with the under running third rail and no adjustment of any kind was ever needed to do this
Per someone's Wikipedia article, the FL9 had "retractable shoes operated by pneumatic cylinders" to facilitate this...but how reliable were these in the long run? and do Amtrak's P32AC-DMs not have such a setup?
Considering that the New Haven Railroad was broke at the time and
maintenance was not always really good, these shoe and shoe mechs.
worked very well. If an FL-9 or pair of FL-9's were operating on diesel
in either Penn Station or GCT, it wasn't very often that the third rail shoes
or mechs could be blamed.
These FL-9 shoes were air lowered and spring raised. When they were
down, the shoe down magnet valve kept the shoe down cylinder charged
but when it came time to raise them, moving the third rail show switch in
the cab would release the air from the shoe down cylinder and at the
same time charge the shoe unlock cylinder to permit the shoes to raise to
the up position by the action of the spring. The shoe up position was a
spring loaded position and the switch would be held up long enough to
raise the shoes.
After Penn Central formed the Metro. region, the shoes were changed on
all of the FL-9's to stationery shoes like the New York Central used and
this made the FL-9's pretty much captive to the west end of the railroad
and they pretty much stayed on the Metro. region with the exception of an
occasional trip to Pittsfield where they were able to continue to operate.
By the time the M-2's showed up, all of the bridges, platforms and other
things that fouled the shoes when down had been modified and so the
thinking was that it was one less thing to maintain.
Noel Weaver