[markus_GE]

Since nobody has started a new wishlist for March yet, I´m doing so, and I´ll add a new item right away :)

A better simulation of the brake system would be appreciated, as the current system does not seem to take into account that Distributed Power Units (DPUs, RC locomotives in the middle (or at the end) of the train) will also supply brake pipe charging air. Thus, on long trains, brake release time currently is longer than it is in reality.

Original description of the problem was brought up by Lindsayts here. I myself can realte to the problem too, though I have only run trains with a maximum of 150 cars in ORTS so far (which amkes the issue less apparent, though brake release still is noticeabley slow - slower than what some websites suggest for similarly long trains)

Cheers, Markus

PS: To the admins: Could anybody please correct the typo I made in the title. Title should be "ORTS Wish List -- 2014-03"
Sorry, I should have looked that I can do this myself... It was a hard week :sign_thanks:

[dforrest]

Can you correct the name of the thread!!!!

[railguy]

The other thing that OR probably does not simulate is the FRED or rear DPU units dumping the air when a emergency brake application is made.

[steved]

I would like to see transparent driver aids with mileposts.
Other than that, this is great work. I remember trying OR several years ago, or right after the first releases, I don't remember.
I went back to MSTS and I was happy.
I just installed both v0.9 and the latest X release this weekend and WOW!
Anyone interested in buying some well used MSTS disks?
Just kidding.

Steve

[ATW]

Would be nice when a coupler is broken for train to go into emergency where angle cock air is opened and dumped till a stop is made.

[Lindsayts]

markus_GE, on 01 March 2014 - 06:47 AM, said:

Since nobody has started a new wishlist for March yet, I´m doing so, and I´ll add a new item right away B)

A better simulation of the brake system would be appreciated, as the current system does not seem to take into account that Distributed Power Units (DPUs, RC locomotives in the middle (or at the end) of the train) will also supply brake pipe charging air. Thus, on long trains, brake release time currently is longer than it is in reality.

Original description of the problem was brought up by Lindsayts here. I myself can realte to the problem too, though I have only run trains with a maximum of 150 cars in ORTS so far (which amkes the issue less apparent, though brake release still is noticeabley slow - slower than what some websites suggest for similarly long trains)

Cheers, Markus

To be accurate the problem of braking on long trains with locos in the middle was actually first discussed quite some time ago so the problem was already known.

Its actually quite complicated as the driver appears to have independent control of the other locos in the consist. If one say is going over the crest of a hill the driver can have the leading locos at low throttle with the brakes being applied but the second set of locos still on notch 8 with released brakes as they are still pulling 15,000 tons up a grade.

Lindsay

[markus_GE]

True on that, Lindsay... but for starters, I´d suggest getting every loco to supply air. If that´s not done, how could one want to control every loco individually?

Cheers, Markus

[eric from trainsim]

I'd like ORTS to play nice and open up .T files which are *not* compressed....

Today, the route will load, but it fails to read the terrain, and also drops all forests to zero altitude...

[railguy]

Lindsayts, on 02 March 2014 - 10:48 PM, said:

To be accurate the problem of braking on long trains with locos in the middle was actually first discussed quite some time ago so the problem was already known.

Its actually quite complicated as the driver appears to have independent control of the other locos in the consist. If one say is going over the crest of a hill the driver can have the leading locos at low throttle with the brakes being applied but the second set of locos still on notch 8 with released brakes as they are still pulling 15,000 tons up a grade.

Lindsay

I think that Lindsay is discussing two different things. With Distributed Power (US version), the engineer can independently control the throttle setting on each set of DP units--for example, the mid-train ("swing") DP units and the rear DP units. Under normal operation, they will follow the engineer's throttle setting in the lead loco. But, if the engineer is, for example cresting a steep grade with a long train, he/she can "build the fence" (as it's known in US railroad jargon) and control the DPU's independently of the lead units. Thus, the engineer can have the lead units already descending the downhill grade with the front part of the train in dynamic braking, while having the swing and rear units still shoving the rear part of the train that is still going upgrade. For the record, the Run8 simulator does allow the engineer to build the fence in those situations, so it can be done in a simulation.

The braking system is another matter, as it responds to the pressure throughout the train line, from front to rear. What the engineer can do with a DPU (or EOT device, the "FRED") is to dump the air from the DPU's and/or FRED by command from the lead loco. This causes the train line to lose pressure more quickly and not just move from front to rear, as the air is exhausted from more than just the lead locos control stand.

Two things that I have not been able to really determine to date:

First, on MU'ed engines, all of the compressors (that are running) should contribute air to recharging the brake system, so a train with 4 locomotives should recharge its air faster than the same train with just 2 locos. I think that is the way it works with MU'ed units in OR, but I'm not sure, and I don't think that DP units contribute now in OR.

Second, some locomotives have air compressors where the air compressor is mechanically powered off of the crankshaft, thus producing more air at higher throttle settings. This MSTS engine parameter recognizes this: " AirBrakesIsCompressorElectricOrMechanical( 1 )" Many EMD locomotives have mechanical compressors, while most GE's are electric. I doubt that OR takes advantage of this to increase the CFM of air flow when mechanical compressors "throttle up" with the diesel prime mover.

Can any of the developers answer definitively how this stuff works (or doesn't) in OR? Thanks.

[Genma Saotome]

railguy, on 03 March 2014 - 11:00 AM, said:

With Distributed Power (US version), the engineer can independently control the throttle setting on each set of DP units--for example, the mid-train ("swing") DP units and the rear DP units. Under normal operation, they will follow the engineer's throttle setting in the lead loco. But, if the engineer is, for example cresting a steep grade with a long train, he/she can "build the fence" (as it's known in US railroad jargon) and control the DPU's independently of the lead units. Thus, the engineer can have the lead units already descending the downhill grade with the front part of the train in dynamic braking, while having the swing and rear units still shoving the rear part of the train that is still going upgrade. For the record, the Run8 simulator does allow the engineer to build the fence in those situations, so it can be done in a simulation.

It gets complex... the above is for modern locomotives but what about earlier times? Seems to me OR should provide for the above and (1) in multiplayer (if not already done) provide for more than one locomotive crew to control independent helpers as well as (2) investigate the feasibility of the AI software doing the above as-if there was other crews in the helpers. By "doing the above" I mean situational differences in control settings between the locomotive(s) controlled by the player and those controlled by AI.