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| Train Type Characteristics 11/01/2021 at 08:59 #136225 | |
mjkerr
174 posts |
Train performance comparison I have now started this to compare : Carnforth - Carlisle non-stop Class 86/1 + 9 Mk3 + NEA 110mph Class 86/2 (110mph modified fleet) + 9 Mk3 + NEA 110mph Class 87/0 + 9 Mk3 + NEA 110mph Class 87/0 + 5 Mk3 (as comparison) Class 47/4 + 9 Mk3 + NEA 95mph Class 37 + 9 Mk3 + NEA 80mph My first has shown no or little difference between 86/1, 86/2 and 87, no matter the length The trains all arrived at Carlisle within 45 seconds! I was expecting the short formed 5 Mk3 to arrive considerably early, but it was just 45 seconds DELETED Log in to reply |
| Train Type Characteristics 11/01/2021 at 09:00 #136226 | |
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mjkerr
174 posts |
Reply by kbarber - As I'd expect really. An 86 is an 86. OK, an 87 has a few more horses, but line speed and traction/rolling stock speed are exactly the same, so the only difference will be in acceleration. On an Inter-City service with few stops (and, obviously, being held to time at each stop) that means almost no benefit from the extra power. An 86 was capable of handling any conceivable Inter-City load at line speed over Shap. The only time you'd really see a difference is on freight, where the acceleration from a stand would become significant. Always interesting when I was in the Brent on nights, to hear a long freightliner going by; they'd be turned straight out on to the down fast at that time of night so by the time the locos (86 + 87) passed the supervisors' office the tail end was just about over the points and the driver was notching up in earnest. You could really hear the power going down onto the rail, and the train (usually 30 flats) accelerated audibly as it passed! Great days! DELETED Log in to reply The following user said thank you: Guts |
| Train Type Characteristics 11/01/2021 at 09:06 #136227 | |
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mjkerr
174 posts |
Perhaps you missed the difference between the three types of Class 86? Class 86/2 - 100mph Class 86/2 - 110mph (86209 / 86224 / 86225 / 86231) Class 86/1 - 110mph } Class 87/0 - 110mph } These two are identical, and in the test they arrived at the same time The 110mph Class 86/2 should arrive between the two, as they have the higher maximum speed, but less power However, that is not what happens and they have the same as the Class 87/0 It is quite obvious on the Class 47/4, I assume this is a combination of 95mph and the diesel power profile Equally, even more obvious when using Class 37, with 80mph In 1988 there is a note in the West Coast Operations manual that if the 110mph Class 86/2 are used north of Crewe on a London Euston departure with 110mph Mark 3 coaches then an additional 3 minutes allowance is given per station stop, arrival in Glasgow Central of up to 15 minutes late can be expected DELETED Last edited: 11/01/2021 at 09:09 by mjkerr Reason: None given Log in to reply |
| Train Type Characteristics 11/01/2021 at 09:15 #136228 | |
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mjkerr
174 posts |
Steamer in post 136222 said:As for the latest problem, you'll need to change the Acceleration/Brake and Weight categories appropriately Length does affect performance, and is very obvious on longer trains It is even noticeable between a standard nine Mark 3 + NEA and The Clansman eleven Mark 3 + NEA With this longer set the Class 87/0 climbs Shap down and drops to 107mph DELETED Log in to reply |
| Train Type Characteristics 11/01/2021 at 09:46 #136229 | |
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Albert
1313 posts |
I think most passenger trains drop their speed somewhat on that section. Also, there are some speed limits due to the curves of the route anyway so don't expect 125mph all the way. A long train just takes longer to clear a speed restriction, and by the time it has fully cleared the restriction it may find itself on a slope, limiting acceleration. If there is a slope shortly following a speed restriction (which, I think, is very well possible on Carlisle) length can affect the speed of climbing trains. AJP in games Log in to reply |
| Train Type Characteristics 11/01/2021 at 11:27 #136230 | |
kaiwhara
584 posts |
There are limitations as to how detailed you can go with Train Performance within Simsig. This is especially apparent given we only have 5 acceleration profiles, and 3 weight categories. Apart from a 10mph difference in top speed between the loco subclasses mentioned, the difference would largely be negligible. In terms of how a 10 car train hauled by an 86 would behave vs a 5 car train hauled by the same loco, if a section of line is relatively high speed with very few interuptions to that ruling speed (for curves and grades), I'd still expect the difference to be negligible as the real difference is only in acceleration and braking. Once a train is at speed and is unimpeded, the length and weight will make little difference. Where it will make a difference is when the line has lots of curves and grades and therefore a variety of speeds being experienced, be that by the posted speed reductions dictated by the track, or the performance of the train itself. This is where the acceleration profile will be important as I would expect an 86+10 would fit a medium acceleration profile, whereas an 86+5 might make it into a high acceleration profile. As both trains are still very light, I would not expect to use a weight profile of anything other than "normal" (remembering that the hierarchy of weight profiles is rather counter intuitively named Normal - Light - Heavy in that order.) Both trains should have little trouble maintaining good speed up Shap. Remember, that in the UK, gradients are fairly generous compared to the likes of the US, Australia, New Zealand and large parts of Europe. As a rule of thumb, I personally only use Light on empty or known lightly loaded freight trains, and heavy for loaded. Of course, in the real world, there are a lot more variables than that. From experience as a Driver for example, I could haul 5 ex BR Mk2 Coaches with a DC class locomotive (about 1400hp available at the rail) up a 1:40 grade at 70kmph in notch 8 power provided I was doing at least that speed at the bottom of the hill and had no reason to stop. If I had to attack that same gradient from a standing start (and the grade I'm thinking of had 3 stations on it), I'd have no hope of ever making 60kmph, and a lot of the DC class wouldn't even make 55kmph. Simsig (currently) can't handle that granular level of train performance detail, nor is it really designed to. In short, I hear what you are saying, but for me my question is, does it really matter that much if performance does not exactly match the real world, when it does a fairly good job of approximating what is a wildly variable subject at the best of times? As long as a 5000T Coal Train crawls up the hill from Epping to Hornsby on the Main North Line out of Sydney at about 20kmph with 4 82 class on the head, I'm personally quite happy. Sorry guys, I am in the business of making people wait! Last edited: 11/01/2021 at 11:28 by kaiwhara Reason: None given Log in to reply The following users said thank you: DonRiver, kbarber |
| Train Type Characteristics 11/01/2021 at 11:44 #136231 | |
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Albert
1313 posts |
I believe the original Carlisle 79-80 TT had to be tweaked to achieve correct travel times, at the expense of realistic acceleration in the station area - although this has probably been improved somewhat in later sim or loader updates. That makes it somewhat hard to say which settings are 'right' for a certain type of train.
AJP in games Last edited: 11/01/2021 at 11:45 by Albert Reason: None given Log in to reply |
| Train Type Characteristics 11/01/2021 at 12:58 #136233 | |
Steamer
3921 posts |
mjkerr in post 136228 said:Steamer in post 136222 said:Hold on a moment. Your original post said:As for the latest problem, you'll need to change the Acceleration/Brake and Weight categories appropriately Quote: My first has shown no or little difference between 86/1, 86/2 and 87, no matter the lengthNow you're telling us the effect is "very obvious". Albert and Kaiwhara have given a comprehensive overview of the options available- as I said, you'll need to modify the acceleration/brake and weight characteristics if you expect to see a substantial difference in run times; though subject to the caveats they've described. EDIT: Where did you record the 107mph speed? The only section of the Down line south of Shap cleared for more than 105mph is Carnforth- Milnthorpe. Incidentally, a run of 6 miles at 107mph instead 110mph is a time difference of about 5 seconds. "Don't stress/ relax/ let life roll off your backs./ Except for death and paying taxes/ everything in life.../ is only for now." (Avenue Q) Last edited: 11/01/2021 at 16:33 by Steamer Reason: None given Log in to reply The following user said thank you: jc92 |
| Train Type Characteristics 11/01/2021 at 13:10 #136234 | |
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bill_gensheet
1314 posts |
At least on the passenger side there are not that many timing load values in the working timetable anyway. For WCML of the 1980's it is usually E455 or E595 with the occasional 210 and 315, and some trains noted as OK for 110mph. Makes sense as only a few train performance profiles would be fully calculated. So as long as all trains can meet the timings the driver could drive at less than 100% 'welly' on the slightly lighter ones (eg load 11 timed as E455). Bill Log in to reply |