Realistic Brake Pipe Charging Rate

[Shortliner]

What would be a realistic Brake Pipe charging Rate? I currently have mine set on the default 20 PSI/s, but I don't know if that's too slow or not. It does seem to take awhile for the brakes to charge up and I can move my train.

[mikeebb]

It should depend on the real locomotive's compressor output. Older locomotives would have a lower charging rate; newer ones generally higher. 20 is a compromise which is appropriate as a default. Unfortunately, in both OR and MSTS I can't be sure that all the locomotives on the train are actually charging the brake pipe; in fact, I suspect not, especially for distributed power, which is one of the reasons for using them in real-life (charge both ends of the train reducing release time).

OTOH, the default charging rate *does* release the brakes in a realistic time in OR for a model that's properly set up. MSTS releases much too quickly, consistent with "game" usage rather than true simulation. In real life, it takes a while to pump up a long train in the yard. For short and passenger trains, though, and for release of minimum sets, it does seem to take too long; again, depending on the particular model and the age of the prototype. My particular gripe in some models is the long time it takes for the engine brake to come completely off when reducing the independent brake or bailing off. Yes, .eng and .wag files can be adjusted and should be; in some cases, they may have charging rates and other brake parameters "unnaturally" tweaked to produce more prototypical action in MSTS, which OR then exaggerates.

A shortcut is to "initialize brakes" (shift /) if you're tired of sitting there watching the numbers slowly change. Also, if you've been switching, make sure all the brake hoses are connected and angle cocks set properly; an open brake pipe can be really hard to pump up, and a closed angle cock between the locomotives and the train or between cars mid-train can just ruin your whole day going downhill.

[R. Steele]

What would be a realistic Brake Pipe charging Rate? I currently have mine set on the default 20 PSI/s, but I don't know if that's too slow or not. It does seem to take awhile for the brakes to charge up and I can move my train.

In my estimation anyone with questions about physics in OR should start at these pages >>> http://www.coalstonewcastle.com.au/physics/ and especially for this thread >>> http://www.coalstonewcastle.com.au/physics/brakes/

I have been reading and studying these, lots of information. Now I've learned that train simmers can be a dang consarned opinionated bunch of knotheads at times. So however you agree or disagree with the parameters listed on these pages...they are IMHO one of the few places to start, for the present.


PetPeeve: Not many read the manual, lots of valuable stuff in there. After all these years with MSTS and hardly any documentation you'd think folks would be overjoyed having a REAL manual, updated and maintained!!

from the manual...
6.1.7 Brake pipe charging rate
The Brake Pipe Charging Rate (psi/s) value controls the charging rate of the main air brake pipe. Increasing
the value will reduce the time required to recharge the train (i.e. when releasing the brakes after a
brake application), while decreasing the value will slow the charging rate. See also the paragraphs on
the OR implementation of the braking system.
If this parameter is set at 1000, a simplified, MSTS-like braking model is implemented, providing for
faster brake release and being less influenced by incoherent braking parameters within .eng file.

Lots more in there about brakes.

And while I'm on this mini-rant (my apologies to Sean, nothing directed towards your post or yourself): An effort made to improve the physics parameters on eng and wag files will payoff in OR. The trains actually have WEIGHT, you can feel the tonnage, they take time to start, release brakes, reach speed, and take considerable time to stop. This is starting to become fun and hard, challenges your skills.

...and after wading through all my bothersome blather Sean ... Take Mike's excellent advice. But also read Peter's pages linked above.