Wow. That sounds like it was the mother of all derailments!
SCLJim wrote:So browsing through the different threads on physics, I think the general consensus was 12-13% for a loadable/unloadable car, to average things out. So my question is, what percentage would you use for a flat out empty and load? I'm guessing the 12-13% still for the load but what would be a good figure for the empty version?
I think if you are going with different weights on MT and LD cars -- in which case I would suggest setting only one weight ("MASS") in the blueprint and leaving the cargo capacity weight setting at or near 0 -- you could use absolutely spot-on max braking force settings.
For example, you could pick Bill "TurboBill" Prieger's Pro Physics brake force settings from MSTS and use them as a starting point. Seeing that KRS and MSTS originated from the same software design studio, chances are that the underlying car physics calculations aren't all that different. So for example, a 27.5t car with cast iron brakes gets a 21.8kN max brake force with Bill's physics pack. For RW, that would get you a MaxBrakeForce% of 79%. A 100t car gets 39.4 kN max brake force, so that would be 39%.
In one of my old physics mod files from the wild MSTS days I also found some references that quote some AAR figures for maximum brake forces at 50 psi brake cylinder pressure: loaded cars mass*0.3 (0.39 for T/COFC) -- empties same as loaded, but not more than (empty mass * 1.2)
philmoberg wrote:That said, there could problems with a wide variety of passenger brake valve schedules in a single consist.
This is fascinating stuff, Phil! I'm afraid Railworks is much too forgiving to simulate anything like this, I've been running long trains with mixed extreme brake settings strewn throughout the consist, and it didn't seem to have any bad effects on train handling. Probably because the air doesn't propagate along the train.