Genma Saotome, on 25 April 2019 - 08:03 AM, said:
Minor comment. IMO MaxReleaseRate (6) is too low. I looked into this last year and concluding something in the range of 16-20 was likely correct. I asked and got numerous comments from engineers and many said what boiled down to almost instantaneously while others said a couple of seconds for the whole train. Based on that, I built a 60 car consist, set the brakes, released them (rinse and repeat) until the head of the train train took 5-6 seconds from showing released to hit zero. A fast release rate has no effect on how long it takes to pump up the line.
I recall reading your comment to that effect. Testing my values with a 60-car train, if I go to full service braking, it takes about 45 seconds for the last car's brake cylinder pressure to reach 64 psi. The first car takes about 11 or 12 seconds, which is about right given the 6 psi/sec MaxApplicationRate. As for release, it depends upon whether on not the Graduated Release Air Brakes box is checked in the options menu. If it's checked, it takes about 65 seconds before the last car fully releases (i.e. way too long). If it's not checked, which should be the case for freight trains, it takes about 16 seconds. This seems about right given the values I have. I figure about 11 or 12 seconds for the actual release, and about 5 seconds for brake propagation. Changing the MaxReleaseRate to something like 20 should get the brakes to release in under ten seconds. Also, you would probably have to change the TrainBrakesControllerMaxReleaseRate to something high enough to allow at least a 20 psi/s release rate. Based on a triple value ratio of 2.5, then means this parameter should be at least 8, not the 1.7 I was using.
That brings me to another thing I wish the Open Rails programming team would implement. A lot of people run both freight and passenger trains. For freight trains unchecking the Graduated Release Air Brakes box gives correct operation. For passenger trains the box needs to be checked. There should be a parameter in the .eng file which overrides this setting so you don't have to check it or uncheck every time you switch from passenger to freight. I suggest something like ORTSGraduatedReleaseAirBrakes. You would use ORTSGraduatedReleaseAirBrakes ( 0 ) for freight locomotives and ORTSGraduatedReleaseAirBrakes ( 1 ) for passenger locomotives.
EDIT:
I just tried changing MaxReleaseRate to 20 for both the freight cars and locomotive. I also changed TrainBrakesControllerMaxReleaseRate from 1.7 to 8. Now the brakes release on an entire 60-car train in about 6 seconds. That's probably about as fast as is possible unless you're using ECP brakes which transmit the brake signal electrically.