[Matej Pacha]

Recently the voices has been heard and the adhesion model is tuned now (since v1664). You should be able to use the full throttle for a train start, even with a sander. The adhesion limit corresponds to Curtius-Kniffler adhesion data in both advanced and simple mode.
I've tested this with Marias Pass - Noon Mixed Freight activity and on the most "devil" grade I got "coupler overload" message right behind the third engine - be careful and watch your tractive force or you could loose the train :) (ergo how MSTS designed their activities and did their models...)

Matej

[_o_OOOO_oo-Kanawha]

Interesting development. Where do you get that message, on one of the Shift-F5 screens? Or is it displayed amongst the control information messages?

Do couplers actually break and make the train go into emergency, like in Trains 12's Mohave/Tehachapi route?

[copperpen]

Matej

Thank you for sorting this out. My test train on my chosen test route behaves as predicted by power and train weight, can even run in notch 8 in the snow with sanders now. I did have to change the sanding speed in the MSTS eng file though to achieve it.

[captain_bazza]

Quote

I've tested this with Marias Pass

The MSTS default MP is infamous for its inaccurate grades in the ++3%> range. The Settle & Carlisle would be better, IMO.

Cheers Bazza

[Matej Pacha]

_o_OOOO_oo-Kanawha, on 23 June 2013 - 01:39 PM, said:

Interesting development. Where do you get that message, on one of the Shift-F5 screens? Or is it displayed amongst the control information messages?

Do couplers actually break and make the train go into emergency, like in Trains 12's Mohave/Tehachapi route?

the information was hidden in the force info view due to high number of cars. With the new locomotive info I can see the most loaded coupler - right behind 3rd locomotive. Going into emergency depends on the menu setting. It was just an interesting observation of the original MSTS activity on the original route.
The ENG file setting of the sander max speed also doesn't make any sense to me. Usually in real world the speed is measured on wheels. If it would be like in MSTS, when you get the wheel slip, indicated speed could be above this limit and disable your last chance of getting the wheels under control.
Just let me know if the changes of the adhesion are a step forward.
Thanks,
Mate

[copperpen]

To me, this adhesion model is the best one yet, and probably will not need further tweaking.

My test route is Crawford Hill which includes a good stretch at 1.73% and my test train is 49 mixed cars at 5700 tons plus two dash9s on the head end. The Al Krug calculator states that 8800HP will take this train up a 1.73% grade at about 14mph. I reduced the HP figure to 85% of the full figure to allow for internal friction and other causes. The train climbs the 1.73 sections of the route at between 12 and 13 mph.

Now sanding. In the real world when wheelslip occurs the first thing you do is close the throttle to stop the wheelslip. Then if needed apply sanding and open the throttle again. Sanding becomes ineffedtive at high speeds because the sand gets spread far thinner on the railhead, so is only really useful at slow speeds. OR does read the Sanding line in the MSTS eng file, so I have my speed set at 15mph. Over this speed the effectiveness of sanding is greatly reduced so requires greater attention to be applied to the handling of the train when climbing hills. To me, this makes running the sim much more interesting than setting the throttle and sit back to watch the train chug over the hill.

[Matej Pacha]

This sanding thing - I understand the sanding loses its effect with speed, a kind of linear or quadratic dependency. This is already programmed but it's suspended because the settings require nonstandard ENG entry. With the new OR definition file it will be re-enabled.
Thanks for testing...
Matej