[steamer_ctn]

Genma Saotome, on 19 March 2016 - 10:59 AM, said:

Ok... was able to track down what I think is going on: Missing value for ORTSUnbalancedSuperelevation ( ). No default value supplied by the software?

The default values have been checked. There was no default for freight stock, and this has now been adjusted in #3481.

[Genma Saotome]

Thanks Peter. This has been driving me nuts for some time... seeing a string of 60t cars fail a 250r curve at 20mph. It made no sense. But then I suppose not having any Unbalanced Super Elevation margin of safety will do that.

[Genma Saotome]

Peter, this came thru the STMFC list on yahoogroups:

Quote

Taken from an NKP Center of Gravity Diagram book - date unknown - presume 1930 to 1935

Tank Car - 10,000 gallons - mty wgt 46,064 lbs - CoG = 48.25 inches
loaded with 10248 gallons of gasoline - actual wght 105,862 - CoG 72.187 inches
loaded with 10,248 gallons of mineral oil - actual wght 125.656 - CoG 75 inches

Coal Hopper - 50 ton - mty wght 39,600 - CoG = 39.0625 inches
loaded with a 10 inch heap - actual wght 140883 - CoG = 70.625 inches
loaded with a 30° heap - actual wght 151,632 - CoG = 63.125 inches

Gondola - 50 ton - mty wght 44,100 lbs - CoG = 33.125 inchesg
loaded with coal - 10 inch heap - act wght 143341 - CoG = 63.75 inches
Loaded with coal - 30° heap - actual wght 157445 - CoG = 68.5 inches

Boxcar - 40 ton - 3736 cuft - mty wght 46450 lbs - CoG = 56.0625 inches
loaded with oats - actual wght 136000 - CofG = 84.75 inches
Loaded with corn - acyual wght 136000 - CoG = 69.0625 inches

Reefer ARTCo blt 1926-1927 - 40 tons - mty wght 52362 - CoG = 61.5 inches
mty car with 9615 lbs of ice in bunkers - actual wght 61977 - CoG = 69.03 inches


Super elevation back prior to the FRA, and when cars were not as tall was 7 inches max where passenger trains were operated, and the speed & radius required it. For frght only lines the max was 4 to 5 inches max.

Generally 1.5 inches of underbalance was - and still is - a safe maximum for frgt cars. Passenger trains normally operated at 3 inches of underbalance. Underbalance is how many inches a pendulum deflects while going around a curve. Envision an equilateral triangle with 56.5 inch side set up inside a car. A pendulum attached to its upper junction point. On straight track the pendulum hangs straight down at the zero point on the scale. Then we head into curve with no superelevation, the pendulum deflects outward 1½ inches. If that same curve had 1½ inches of superelevation, and the train was moving at the same speed as above, the pendulum would stay at zero. Hint - the triangle uses legs that are the same length as track gauge.

Even today's taller hicube cars when stopped on a curve with 4 inches of SE, still need a good crosswind - say 60+ MPH - before there is a likelihood of an mty car blowing over. Loaded cars would take tornado like winds to blow them over. Today you would need about 20 inches of superelevation to reach where a car would tip over. The actual angle would be determined by a triangle formed with a base of 56.5 inches and the other two equal legs of the length from the gauge point to the CoG elevation on the centerline of the car. When the CoG point tips far enough so that it is outside to the gauge line, the car tips over.

Mark Landgraf
Albany NY
railroad office engineer

[steamer_ctn]

Hi Dave,

Genma Saotome, on 21 March 2016 - 08:04 PM, said:

Peter, this came thru the STMFC list on yahoogroups:

Thanks for that.

I am wondering whether some "rules of thumb" can be developed for CoG when it is not easily available.

For example, I use the centreline of the boiler on a steam locomotive as an indicative CoG for it.

Perhaps the information that you have sourced, along with the relevant wagon dimensions could be used to develop some rules.

WDYT, and are you willing to have a go at it?

Thanks

[Genma Saotome]

I think some CoG numbers can be produced for some pre-1960 North American freight cars but I'm doubtful beyond that. That will be better than nothing.

I also have a large amount of data on both empty and loaded freight cars and so using the examples above I can easily extrapolate numbers for all sorts of other situations... but again, my expertise -- and data -- is very limited in scope. But as I said,certainly better than nothing.

My math skills are fairly mediocre... CoG is a median number, not an average. I can see my way into figuring out where the median CoG is relative to the floor, I have a couple of hundred commodities with average carload weight on hand... not to hard to use google to locate density and, being ignorant of any clever solution, I suppose one could use a spreadsheet, a typical floor area, and run a set of numbers by the inch to see how much cubic inch of stuff, spread across the floor, will weigh... then how many inches above the floor for many commodities on up to typical lading weight. I suppose the median should be easy to figure from that.

Or is there an easier way... or do you suggest using the tried and true WAG (I expect this may be only an American acronym but the last letter is for guess)?

[Genma Saotome]

As an example, here are average lading weights for a couple hundred commodities, data from two different years.

ICC	Commodity	1947	1956
Code	Class Name	Tons/Car	Tons/Car
1	Wheat	52	54
3	Corn	50	54
5	Sorghum	49	54
7	Oats	40	41
9	Barley	48	50
11	Rice	45	41
13	Grain NOS	36	33
15	Flour - wheat	38	32
17	Meal - Corn	34	32
19	Flour - edible	36	27
21	Cereals	23	19
23	Mill products NOS	32	29
25	Hay	15	15
27	Straw	16	12
29	Tobacco	14	15
31	Tobacco waste	26	31
33	Cotton bales	22	16
35	Cotton -raw	21	22
37	Cottonseed	29	31
39	Cottonseed Oil cake	35	36
41	Cotton seed hulls	24	24
43	Soybeans	49	53
45	Soybean Oil Cake	37	40
47	Vegetable oil cake	34	30
49	Apples	20	19
51	Bananas	12	11
53	Berries	21	21
55	Cantaloupes	12	12
57	Grapes	17	16
59	Lemons	21	19
61	Oranges	23	22
63	Peaches	13	14
65	Pears	19	20
67	Watermelons	13	13
69	Fruit, fresh	14	13
71	Fruit, dried	36	35
73	Fruit, frozen	28	28
75	Coffee	31	26
77	Cabbage	13	14
79	Celery	12	12
81	Lettuce	12	12
83	Onions	15	15
85	Potatoes	21	19
87	Tomatoes	13	12
89	Vegetables, fresh	13	13
91	Beans, dried	37	39
93	Vegetables, dried	33	24
95	Vegetables, frozen	32	30
97	Peanuts	26	22
99	Sugar Beets	39	48
101	Malt	42	43
103	Flaxseed	47	49
105	Seeds NOS	28	28
199	Other produce NOS	22	24
201	Horses	12	12
203	Cattle	11	11
205	Calves	14	10
207	Sheep - single deck	8	7
209	Sheep - double deck	10	10
211	Swine - single deck	9	7
213	Swine - double deck	13	12
215	Meat, fresh	13	12
217	Meat, cured	20	17
219	Packing House Products	20	22
221	Margarine	22	25
223	Poultry - live	7	7
225	Poultry - cooked	17	18
227	Eggs	16	13
229	Butter	17	18
231	Cheese	21	19
233	Dairy products	23	21
235	Wool - greased	16	17
237	Wool	12	12
239	Hides	32	29
241	Leather	20	23
243	Sea food	19	21
245	Fish oil	27	25
299	Animal products NOS	28	31
301	Anthracite Coal	57	57
303	Coal to washeries	63	63
305	Bituminous Coal	57	62
307	Coke	36	39
309	Iron Ore	65	67
311	Aluminum Ore	58	61
313	Copper Ore	57	61
315	Lead Ore	53	66
317	Zinc Ore	54	56
319	Misc Ores	56	62
321	Barytes	46	50
323	Clay	42	50
325	Sand - Industrial	56	61
327	Gravel and sand	57	61
329	Stone, Crushed	55	59
331	Fluxing stone	63	66
333	Stone, rough	46	50
335	Stone, finished	28	22
337	Petroleum	36	38
339	Asphalt	37	37
341	Salt	40	42
343	Phosphate	50	62
345	Sulphur	58	65
399	Products of mines NOS	52	58
401	Logs 	34	35
403	Posts or Poles	29	28
405	Wood - fuel	35	38
407	Ties	34	33
409	Pulpwood	40	43
411	Lumber	34	32
413	Box materials	25	21
415	Plywood	38	33
417	Rosin or Turpentine	27	28
499	Wood, NOS	23	23
501	Gasoline	27	30
503	Diesel Fuel	32	33
505	Lube Oil	26	24
507	Refined Products NOS	28	25
509	Gases	25	33
511	Cottonseed oil	30	30
513	Linseed Oil	28	30
515	Soybean Oil	31	31
517	Vegetable or Nut Oil	30	28
519	Oil sediment	27	34
521	Oil foots	28	31
523	Rubber	38	37
525	Rubber goods	20	14
527	Chemicals	32	37
529	Suphuric Acid	53	57
531	Acid, NOS	36	38
533	Soda	44	49
535	Alcohol	27	28
537	Blacks	27	31
539	Fertilizer	45	46
541	Insecticide	25	29
543	Tar	42	42
545	Tanning Material	33	30
547	Paint	28	25
549	Plastics	21	30
551	Cellulose	14	13
553	Drugs	25	20
555	Aluminum Bar	51	49
557	Aluminum Ingot	27	22
559	Copper Ingot	54	54
561	Copper or Brass, NOS	34	38
563	Lead or Zinc Ingot	52	48
565	Lead or Zinc, NOS	25	25
567	Magnesium	35	42
569	Alloy for Steel	54	51
571	Metal Alloys	37	50
573	Pig Iron	54	58
575	Steel, billet or bloom	56	60
577	Steel Bar, Rod, or slab	52	58
579	Steel, NOS	55	60
581	Steel, Nails or Wire	27	29
583	Steel, Manufactured	37	43
585	Iron Pipe	28	30
587	Pipe fitings	32	38
589	Tanks	15	18
591	Farm tools	16	13
593	Farm Parts	24	22
595	Machinery	19	21
597	Machine parts	24	25
601	Office machines	12	14
603	Railroad cars	30	34
605	Railroad car equipment	22	27
607	Railroad car parts	31	33
609	Railroad track	49	44
611	Vehicles	12	11
613	Cars	7	7
615	Trucks	8	10
617	Vehicles, NOS	16	17
619	Military Vehicles	30	57
621	Non Motorized Vehicles	20	22
623	Auto Parts	18	16
625	Aircraft parts	10	11
627	Tires	17	16
629	Guns	21	21
631	Explosives	26	36
633	Cement - natural	46	53
635	Cement - other	31	36
637	Brick, common	44	43
639	Tile	28	36
641	Brick, refractory	43	42
643	Fake stone	33	34
645	Lime	38	43
647	Plaster	33	29
649	Sewer Pipe	22	20
651	Brick, broken	45	46
653	Woodpulp	46	45
655	Paper, scrap	19	21
657	Newsprint	29	28
659	Paper, printing	29	27
661	Paper, wrapping	29	27
663	Paper, bags	26	23
665	Paper, NOS	18	15
667	Printed matter	32	22
669	Cardboard	27	31
671	Wallboard	30	29
673	Paper, roofing	30	27
675	Insulation	16	13
677	Woodwork	24	23
679	Building Material	16	16
681	Houses	19	20
683	Asbestos	16	16
685	Electrical Goods	24	24
687	Furnaces	15	14
689	China Fixtures	18	15
691	Misc. Hardware	21	21
693	Glass	36	35
695	Glassware	18	16
697	Glass, bottle or jar	22	19
701	China	20	15
703	Woodenware	21	18
705	Household utensils	14	12
707	Refrigerators	11	10
709	Laundry equipment	11	11
711	Stoves	13	11
713	Flooring	23	22
715	Furniture	9	8
717	Furniture Parts	16	14
719	Tools	20	12
721	Abrasives	23	26
723	Burlap bags	21	22
725	Cotton bags	21	19
727	Cotton fabrics	14	23
729	Cotton products	14	13
731	Nylon	19	21
733	Cloth	17	21
735	Rope	22	17
737	Boots	14	15
739	Luggage	11	9
741	Sports gear	19	16
743	Games	13	14
745	Liquor	24	27
747	Wine	29	29
749	Beer	29	30
751	Beverages	32	41
753	Ice	27	27
755	Syrup & Molasses	36	34
757	Molasses	45	49
759	Sugar	44	43
761	Candy	25	22
763	Food Products	32	30
765	Frozen food	22	33
767	Starch	33	30
769	Soap	28	23
771	Matches	17	15
773	Animal feed	30	27
775	Cigars	23	29
777	Cigarettes	25	26
779	Empty Cans	10	10
781	Wood boxes	11	11
783	Cardboard Boxes	19	17
785	Containers	12	12
787	Containers, returned	18	15
789	Scrap metal	41	46
791	Scrap borings	44	50
793	Slag	57	57
795	Waste to melt	37	40
797	Waste	34	49
799	Other Mfgd Goods	20	21
950	Forwarder Freight	19	11

FWIW, having data in hand like this may help explain, in part, why I think lading weight belongs somewhere besides .wag files. Let Mass() in .wag's be for empty cars. Let's put the lading (name and) weight somewhere downstream, maybe .con... or as part of the set of activity files. Would greatly simplify what people have in the \trainset folders.

[sim-al2]

The AAR Circular for Closed Cars specifies that:

Quote

Combined center of gravity of rail car and contents must not exceed 98 inches above top of rail.

It appears that individual railroads allow higher COG in some cases, BSNF for example 110 inches, but with the warning that:

Quote

the 110” maximum restricts train handling and operations

[steamer_ctn]

Genma Saotome, on 21 March 2016 - 11:28 PM, said:

Or is there an easier way... or do you suggest using the tried and true WAG (I expect this may be only an American acronym but the last letter is for guess)?

I think that we can do a bit better then a WAG, perhaps an EG (educated guess).

My thinking in order of priority is:
i) any published figures readily available
ii) use a combination of the method described in the AAR circular for cars, and your approach to calculate the load height and density based upon the weight carried, etc
iii) the simplest approach is probably to use the mid point of the load area. For example, a box car the mid point of the "box", for a tanker, the centreline of the tanker.

Option iii) will nearly always provide a "worst case" scenario, and should be quick and easy to calculate. However, if more accuracy is desired then option ii) could be used, as it will provide a more accurate result.

[lateagain]

Updated my version to 3477 today and the issue is still not resolved.

Ridiculously fragile, makes driving a train almost impossible. This cannot be realistic. If it was Railroads would all be rusting rails hidden in weeds and crossed by tumbleweed by now :rolleyes:

Whilst the vast improvements in physics are to be welcomed until a utility to fix MSTS stock is developed I'd suggest some sort of compromise setting to switch the physics used? Finding two pieces of MSTS stock with the same physics is hard enough and if EVERY eng and wag file has to be edited "longhand" that'll be a massive disincentive for folk to use it?

At the very least you should be able to take a curve within the route's speed limit? The fact that not all routes have correctly flagged speed limits is itself an issue but whilst OR depends upon the vast heritage of MSTS content it has to compromise to some extent. If it doesn't it ceases to be a viable Train Sim for most folk? :ermm:

[Genma Saotome]

lateagain, on 23 March 2016 - 07:29 AM, said:

Updated my version to 3477 today and the issue is still not resolved.

Not recent enough... IIRC you need 3482.