Steam Engine exhaust with closed throttle

Locomotive chuffing volume is controlled by the following formula, it is proportional to the effort the engine puts up at a time:

Variable2 = Math.Min(CylinderPressurePSI / MaxBoilerPressurePSI * 100f, 100f);

This variable is closely related to the actual steam locomotive physics calculations. In MSTS the steam physics is completely different, and probably partly broken. Thus replicating the behavior here is nearly impossible. This was discussed on ET, and based on the discussion I would mark this bug report as "Won't fix" status.

Regardless of the formula and regardless of whether MSTS is right, wrong or broken, when you close the throttle on a steam locomotive the exhausting stops. Period. Such should be the action in ORTS, and it is not.

Herb Kelsey
In God We Trust

-----Original Message-----
From: <email address hidden> [mailto:<email address hidden>] On Behalf Of Peter Gulyas
Sent: Thursday, November 20, 2014 12:08 PM
To: <email address hidden>
Subject: [Bug 1393270] Re: Steam Engine exhaust with closed throttle

Locomotive chuffing volume is controlled by the following formula, it is proportional to the effort the engine puts up at a time:

Variable2 = Math.Min(CylinderPressurePSI / MaxBoilerPressurePSI * 100f, 100f);

This variable is closely related to the actual steam locomotive physics calculations. In MSTS the steam physics is completely different, and probably partly broken. Thus replicating the behavior here is nearly impossible. This was discussed on ET, and based on the discussion I would mark this bug report as "Won't fix" status.

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https://bugs.launchpad.net/bugs/1393270

Title:
  Steam Engine exhaust with closed throttle

Status in Open Rails Tracker:
  New

Bug description:
  When you close the throttle on a steam locomotive in ORTS the exhaust
  continues as though it were open and pulling. I have discussed this
  issue on the ET forum but it is time to memorialize it with a bug
  report.

  Steam locomotives DO NOT chuff with the throttle closed and coasting.
  MSTS properly stops chuffing when the throttle is closed but OR does
  not. Some folks have found a workaround by altering a locomotives
  .sms file, but this is a compatibility issue with MSTS and the users
  shouldn't have to restructure every .sms file in their Trainset folder
  to work around an OR glitch.

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Peter Gulyas:

I am Andre Ming, a long time follower of OR progress, a recently added Team Manager, as well as a life-long railroading enthusiast/employee. I have been in and around US railroading since about 1970, first mainly as a ground crewman. In as early as 1980 or so, I became involved with a steam powered tourist operation. My involvement with the tourist operation at first consisted of assisting in any way I could as a crewman and/or event organizer/director. By the mid 1980s in addition to working as a ground crewman, I was firing steam engines as well as running steam engines as a paid employee. I regularly operated three types of steam powered trains: Coal fired, oil fired, and wood fired. From that point on I continued to work as a railroader part time until I made the decision in the mid-2000s to go full time in order to secure a railroad retirement. I am currently a Certified Locomotive Engineer and have worked week in and week out in railroading as an Engineer for many years now running anything from switch engines to 1.5 mile long freight trains, to passenger trains in mainline service.

I say the above to quantify the input I'm about to share.

As Herb Kelsey has pointed out: OR does NOT handle sound sms files in a way that is ACCURATE or REALISITC for North American steam railroading. All North American steam locomotives that I have either run, ridden, or observed, in various parts of North America do NOT chuff when the throttle is closed and the engine is drifting with throttle off or nearly off. If OR purports itself to be a SIMULATOR and strives for acceptable replication of known railroading practices/etc, then this issue NEEDS TO BE ADDRESSED. No one that is reasonably knowledgeable about the operation of steam engines will accept such sound behavior as "realistic" in a supposed railroading SIMULATOR. This should be a BASIC function that steam sounds perform reasonably REALISTICALLY within a simulated environ. Anything less is to detract from the effort and reduce its effectiveness as a sincere effort at creating a railroading SIMULATOR.

Sincerely,

Andre Ming aka "Coonskin" at Elvas Tower

I remember seeing the discussion on ET but can't find it. What was the thread called, please?

Try this one http://www.elvastower.com/forums/index.php?/topic/23560-steam-locomotive-sound-vs-driver-rotation/page__hl__chuff__st__110

And http://www.elvastower.com/forums/index.php?/topic/22676-or-steam-exhaust/page__st__160__p__159494__hl__throttle__fromsearch__1#entry159494 Page 17 in particular.

Herb Kelsey
In God We Trust

-----Original Message-----
From: <email address hidden> [mailto:<email address hidden>] On Behalf Of cjakeman
Sent: Sunday, November 23, 2014 9:15 AM
To: <email address hidden>
Subject: [Bug 1393270] Re: Steam Engine exhaust with closed throttle

I remember seeing the discussion on ET but can't find it. What was the thread called, please?

--
You received this bug notification because you are subscribed to the bug report.
https://bugs.launchpad.net/bugs/1393270

Title:
  Steam Engine exhaust with closed throttle

Status in Open Rails Tracker:
  New

Bug description:
  When you close the throttle on a steam locomotive in ORTS the exhaust
  continues as though it were open and pulling. I have discussed this
  issue on the ET forum but it is time to memorialize it with a bug
  report.

  Steam locomotives DO NOT chuff with the throttle closed and coasting.
  MSTS properly stops chuffing when the throttle is closed but OR does
  not. Some folks have found a workaround by altering a locomotives
  .sms file, but this is a compatibility issue with MSTS and the users
  shouldn't have to restructure every .sms file in their Trainset folder
  to work around an OR glitch.

To manage notifications about this bug go to:
https://bugs.launchpad.net/or/+bug/1393270/+subscriptions

I have accepted (triaged) this report as a bug ready to work on, provided the work meets the post at http://www.elvastower.com/forums/index.php?/topic/25541-compatibility-with-msts/page__view__findpost__p__165903

I.e. The "chuff" when coasting with a closed throttle is silenced when the checkbox "Enhanced compatiblity with MSTS" is checked and otherwise obeys the SMS file.

It would seem that Peter has found the solution. See http://www.elvastower.com/forums/index.php?/topic/25541-compatibility-with-msts/page__pid__166006#entry166006 post #8.

Well done!

Adjusted formula in r2671.