It is a manual valve switch that can isolate the air brake or cut off air in a particular railroad car. A bad anglecock can vibrate loose in transit and cause a air brake to malfuntion and cut off air brake control to the rest of the train.
Most anglecocks actually lock in either the open or closed position. Changing them requires specific actions not usually duplicated by a car running down the railroad.
That’s not to say that it couldn’t happen, but it would be extremely rare.
But it happened to the Federal Express arriving Washington DC shortly before the Inaugural of Dwight D Eisenhower in 1953.
Freight railroad cars have forces not duplicated anywhere elesSlack action,rail joint,hunting trucks,Humping ect. Can cause havoc… freeze thaw cycles ext ext. one even knows how hard it is to turn on the valve for the spinkler system in the spring after a long winter… There are thousands of grain cars that sit idle and anglecocks are a complicated thing so making sure that each work to haul winter wheat on a cold frosty spring morning in Minnisota is life work
Indeed. Never say never…
In many/most cases the handles are held in place by gravity. The right bounce and vibration could result in a closed anglecock.
My Dad had been called to DC for Inaugural duties and brought the entire family along to visit with family in Baltimore. He took me into the basement of WUT to see the wreckage of the GG-1 being readied for removal - all the while its presence there was hidden from the general public by a false floor errected over it.
The GG-1 in question (4876) also wound up being among the last ones in service on the New York & Long Branch between Penn Station and South Amboy.
The story behind this, I found fascinating. Lloyd’s of London was the insurer, and they determined that cutting the carbody into 10’ pieces (I believe to suit the crane size and reach to get out of the hole) would be less expensive than ‘totaling’ and building a new locomotive. The seams from reassembly are still quite evident on 4876, which sat in preservation for some time in the old PSE&G power station’s yard near my house in Englewood, and is preserved today (although not in great shape) outside the B&O museum in Baltimore…