Short turns and brake checks

[Tallguy]

So, I know that any passenger train changing directions at a terminal must test the brakes. Does a short turn require the same test? How about a non revenue turn, such as at SS, going out to Southhampton?

[MBTA3247]

A brake test is required anytime you change which cab you're operating from, to verify that the brake stand at that end is working.

[Tallguy]

Thanks

[CRail]

The brake test is to make sure the brake pipe pressure corresponds with what the automatic brake valve does at the other end. If the rear-most brake cylinder doesn't respond to the brake pipe pressure reduction from the control stand, the test fails and the train can't move until the cause is rectified and a successful test takes place. Every train in North America undergoes this test any time there's any change whether it be the operating stand or equipment added or removed to/from the consist, it is not limited to passenger trains.

[BandA]

Do trolleys & subway cars also require the same full brake tests? Trucks probably have a similar requirement. What do they do in other countries?

[CRail]

Multiple unit vehicles do not utilize the brake pipe to charge and control the brakes. While they do have a brake pipe to initiate an emergency application especially if the train splits, normal applications are an MU feature (an electric signal in the coupler tells each car what to do and each car does it itself). Railroad equipment that doesn’t run Multiple Unit (control cars don’t count since they are just remote controls and do not respond to their own throttles) rely solely on the pipe that runs end to end to charge and control brake applications. So it’s important to make sure the brake pipe is intact and functioning from end to end.

[Tallguy]

So, multiple units don't need a brake test when they reverse directions?

[BandA]

Just make coaches that are non-powered MUs then, with those MU electrically-coupled brakes. QED.

[CRail]

So, multiple units don't need a brake test when they reverse directions?

If referring to railroad MU equipment that still utilizes a "train air" system, then yes, they do. If referring to "straight air" equipment such as LRVs and subway cars, then no, they don't.

Just make coaches that are non-powered MUs then, with those MU electrically-coupled brakes.

Why would someone with such a profound concern of fiscal responsibility want to reinvent the wheel to develop a non-existent technology and convert existing equipment to use it at tremendous capital cost just to avoid a 15 second test at the beginning of a trip?

[Tallguy]

Because the need for brake tests that take 10 or more min to perform according to the MBTA on a route that is only 20 min each way.

[BandA]

I was under the impression from what I read in these forums that a brake test took about 10 minutes, clogging up platforms at South & North stations.

[nomis]

The approximate 10 minutes is more about: passenger movement, crew positioning, and schedule recovery & padding, than the actual time to perform the appropriate brake test.

[CRail]

Because the need for brake tests that take 10 or more min to perform according to the MBTA on a route that is only 20 min each way.

Cite your source please. Even if that were true, it's a federal requirement for all railroad equipment. It is not a problem that needs solving.

[BandA]

My personal automobile does a brake self-test in 5 seconds. Is there any rail equipment using hydraulic brakes? Of course hydraulic fluid is another source of ground water pollution.

[CRail]

Your automobile is not a train, nor is it comparable to one. The poster's question has been answered and I think the discussion is exhausted.