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Delays after TRTS

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Delays after TRTS 16/05/2018 at 06:20 #107972
jem771
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A common delay in the real world is when the station staff operate the TRTS, signaller then sets route and then the train "just doesn't move" !
next thing is the station get on to you asking for the signal to be replaced for whatever reason, no guard, passenger delay, door problem or whatever. you then have to wait for the die-out which causes all sorts of problems espcially at busy stations.
could this be a delay feature for SimSig perhaps?

Jezz
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Delays after TRTS 16/05/2018 at 23:07 #108000
JamesN
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jem771 in post 107972 said:
A common delay in the real world is when the station staff operate the TRTS, signaller then sets route and then the train "just doesn't move" !
next thing is the station get on to you asking for the signal to be replaced for whatever reason, no guard, passenger delay, door problem or whatever. you then have to wait for the die-out which causes all sorts of problems espcially at busy stations.
could this be a delay feature for SimSig perhaps?
Proposal gone on bug board as Mantis 20474 to look at ways of making this more realistic.

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Delays after TRTS 17/05/2018 at 19:14 #108012
chrisdmadd
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this may not be the best place to reply but i would like to see all trains issued with a rating in relation to power. In real life we know every train brakes and accelerates differently.
Id love to see the timetable writers or just as a default setting to have all trains rated 95%-100% power available. This was you will see a more varied and unpredictable train service.

Also random minute or two unexplained delays at stations, for things like late comers or doors sticking etc. Not a reportable fault just a slight delay.

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Delays after TRTS 17/05/2018 at 19:39 #108013
58050
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Trying to sort out the way locomotives perform on a daily basis would be pretty damn difficult to re-create. You'd have use the performance charts for every type of traction unit that ran on the railways. All of the diesel locos built from Cl.56 onwards have only 1 weakfield stage[term used for diesel eletric locos changing gear]. Whereas diesel locos built from the 1955 modernization plan have all got different numbers of field divert stages on them & thus perform differently irrespective of the weight being pulled. Yes you can have low power problem caused by a large number of reasons such as if a field divert doesn't come then the loco would struggle to increase speed despite the amps staying low & the engine on full chat. I tend to create train types with the best options we currently have such as very low acceleration rate for a loaded train & the weight set to heavy & for an empty train low acceleration rate & weight to light. Where this falls down is the acceleration rate of a Cl.47/4+7 coaches would be significantly higher to that of a Cl.31+7 coaches, yet on SimSig when you look at the 'F2' screen both trains accelerate at the same rate. I suspect it's a case of obtaining the performance rates of all the varied locos & units that run or have run on our railways.
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Delays after TRTS 17/05/2018 at 21:26 #108016
Steamer
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58050 in post 108013 said:
Where this falls down is the acceleration rate of a Cl.47/4+7 coaches would be significantly higher to that of a Cl.31+7 coaches, yet on SimSig when you look at the 'F2' screen both trains accelerate at the same rate.
Wouldn't setting them to "Medium Light" and "Medium Normal" approximate this (for example)?

"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)
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Delays after TRTS 17/05/2018 at 22:38 #108018
58050
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No Steamer it wouldn't. I had a chat to a mate of mine the other day about the very ssmr thing. I was upfsting a couple of timetables I wrote 4 years ago for a couple of forth coming sims & needed to bring them up to date. I asked hi9m with regards to a single Cl.90/1 compared to a pair of Cl.86/6s as he is a driver based at Crewe for Freightkliner. I suggested that a freightliner train loaded & being worked by a pair of Cl.86/6 locos would accelerate faster than a single Cl.90/1 & he said yes even thhough alot of the Cl.86/6 locos running in pairs have traction motors isolated. So in view of that I altered tghe acceleration rate of the 2 train types to Low(standard freight) for a pair of Cl.86/6 locos & very low for a single Cl.90/1 even though the Cl.90 has a higher horsepower than a single Cl.86.
I remember getting off a sprinter at Crewe during 1988 whilst going for a TOPS course at Webb House at Crewe[BR training school] & as I walked along P5 in came a Cl.31/4 with an inter-regional service to Plymouth. The train had approx. 9 or Mk.2 coaches on it & a Mk.1 buffet. I waited for the train to depart as I knew there was no way on earth the type would keep time vice a type 4. The Cl.47/4 had obviously failed somnewhere as the train was being worked by a single Cl.31/4. Despite the driver opening the loco to full power from a standing start you could tell that the type would struggle to get up to the trains normal running speed.
The same sort of thing works for freight trains. I remeber very vivldly one morning booked on duty at 04.15 as I was rostered the 2ndman on the Dunstabler cement. Usually you'd travel passenger to Luton & use the type 4(Cl.45/1 or Cl.47/4 in the north end bay off the newspaper train. But on this occasion the train was running from Easrles Sdgs instead of Northfleet. 45007 was on the front & when we rerleived the Toton men off it the engine shut down. The driver off the loco indficated that she had low oil pressure & due to the cant on the Up Fast Line we couldn't get the engine re-started. So we had to go over to the holding sdgs to fetch a Cl.31/1 off to drag the demic Cl.450 off ^ then re-engine the train. I ended up doing the driving to Luton & with approx 12 loaded PDA bogie tank wagons the power handle on the Cl.31/1 was on full power from the moment we departed Bedford all the way to Leagrave station. I don't think we went over 30mph. Now had the Cl.45/0 been on the front we'd have been doing at least 15mph more than what the type 2 prouced & that's where the variation comes in despite the train being heavy. Needless to say the driver didn#t even bother tel;ling me to set back to run round, he got off & went to the north end bay & got the Cl.47/4 onto the back of the train & we ended up going top n tail to the cement works at Dunstable. I stayed om the Cl.31/1 pushing at the rear whilst the driver was on the Cl.47 at the front. Only time I top n tailed up that line. But again that's downb to the peformance aspectg of each type of loco * how well they perform under full power.

Last edited: 17/05/2018 at 22:39 by 58050
Reason: corrected spelling mistake

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Delays after TRTS 17/05/2018 at 23:38 #108019
postal
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I think the real problem lies in the fact that there is a mismatch between the real world understanding of terms like Light or Heavy and Low or High acceleration rates and now the SimSig core code applies them.

Pascal (58050) obviously brings a wealth of real world experience to the table but unfortunately that does not align with what needs to be done in SimSig world to make some trains run to time. He clearly identifies what happens if a train is underpowered for its TT with his examples of Cl. 31 vice Cl. 47 but that is only half of the story as it does not consider trains which have an excess of power. For example, Pascal's comments about double headed Freightliners do not allow at least one sim TT to produce trains that run to time. I think it is a reasonable assumption to make that things like Freightliners would have a TT that was achievable in practice. On sims that have some heavy gradients, the only way in SimSig to make the trains run to time is to set their weights to Light and their acceleration rate to Inter-City.

I believe this is because of the way that SimSig computes the acceleration if my memory of a conversation with Clive some time ago is correct. The core code links the acceleration of the train to the maximum speed given in the train type so that the acceleration tails off as the train gets nearer to its maximum speed as if the train just had enough power to run at maximum speed. In reality, a double headed Freightliner would have ample power to run on the flat far quicker than the 75mph maximum speed and so is still in the steep part of the acceleration curve when it hits 75mph. This means that the train is effectively accelerating far quicker than the core code calculates it should when based on a 75mph maximum speed. In the same way the core code assumes that uphill gradients immediately cause the train to decelerate as it is already running at maximum power to hit its top speed on the flat. With things like a double-headed Freightliner there is still some surplus power so the deceleration can be put off during part of the climb by pushing the handle forward and using more of the available power. The SimSig core code does not allow for that. As far as I am aware the whole rationale for double-heading the Freightliners was not to change their maximum speed but to make their acceleration nearer to that of an Inter-City service in order to maximise line capacity.

Therefore the actual words used in the SimSig world about loads and accelerations do not bear any relation to how some of the trains in the TT would actually run as the core code has no way of seeing how much power the train has available. TT writers need to be aware that real world performance is not replicated by the words SimSig uses and need to consider what the TT hopes to achieve before setting the parameters for a train type.

“In life, there is always someone out there, who won’t like you, for whatever reason, don’t let the insecurities in their lives affect yours.” – Rashida Rowe
Last edited: 17/05/2018 at 23:53 by postal
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Delays after TRTS 17/05/2018 at 23:54 #108020
GeoffM
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It is true that the acceleration curves used in SimSig cannot cater to all the real world scenarios. The problem is getting reliable data for every single train type, consist, and arrangement of stock. That is virtually impossible, especially when the manufacturers show no interest in releasing what they consider to be sensitive information - yes, I tried it for the real world simulators and was denied every single time.

Given a long enough train, the arrangement of wagons within makes a difference too, or at least when gradients affect the train the most (heavy up front or heavy at the rear). Even if we did take that into account, how many of us accurately know every single train that ran that day to know how it was loaded.

Suffice to say there is too much we don't know to be 100% accurate.

What I will say is that we'll look into "over powered" trains. This might be as simple as having an effective maximum speed (based on what it could achieve) and a permitted speed (as per now). That should mean acceleration near the permitted speed is higher than the current method of tailing off.

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Last edited: 17/05/2018 at 23:57 by GeoffM
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Delays after TRTS 18/05/2018 at 00:16 #108021
postal
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Or even just tick in a box for "high-powered train" which could then adjust all of the acceleration rates by a similar proportion. Bit like having a double chain-wheel on a bike with a derailleur block at the back. It would allow for quite a bit of fine tuning by the TT writer to get as near to expected performance as possible.

Without the information which the manufacturers keep close to their chests it would be as difficult to guess a theoretical top speed as it is to calculate an actual expected acceleration rate.

“In life, there is always someone out there, who won’t like you, for whatever reason, don’t let the insecurities in their lives affect yours.” – Rashida Rowe
Last edited: 18/05/2018 at 00:25 by postal
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Delays after TRTS 18/05/2018 at 00:38 #108022
GeoffM
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postal in post 108021 said:
Or even just tick in a box for "high-powered train" which could then adjust all of the acceleration rates by a similar proportion. Bit like having a double chain-wheel on a bike with a derailleur block at the back. It would allow for quite a bit of fine tuning by the TT writer to get as near to expected performance as possible.

Without the information which the manufacturers keep close to their chests it would be as difficult to guess a theoretical top speed as it is to calculate an actual expected acceleration rate.
But what is a "similar proportion"? You could have a permitted maximum of 40mph for one train and 60mph for another train, but weight/distribution/length/overall power identical. If the code decided 25% was a good figure then the effective maximums would be 50mph and 75mph respectively which wouldn't work in this scenario.

True, we may not know whether setting an effective maximum of 90mph would be suitable... so playing about with it may be the only answer, just like gut feelings for acceleration rates and weights are now (cue furious debate over EMU characteristics).

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Delays after TRTS 18/05/2018 at 00:53 #108023
postal
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GeoffM in post 108022 said:
But what is a "similar proportion"? You could have a permitted maximum of 40mph for one train and 60mph for another train, but weight/distribution/length/overall power identical. If the code decided 25% was a good figure then the effective maximums would be 50mph and 75mph respectively which wouldn't work in this scenario.
Whatever the final outcome, the TT writer is probably going to have to fine tune things anyway and we may still end up with some cases where the words don't appear to match the reality. "Similar proportion" was a first stab as throwing ideas onto the table. In the interests of the fine tuning it would probably help if all of the 5 acceleration rates where enhanced for a high-powered train but after that it's a case of trying to find the best compromise. Best of luck.

“In life, there is always someone out there, who won’t like you, for whatever reason, don’t let the insecurities in their lives affect yours.” – Rashida Rowe
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Delays after TRTS 18/05/2018 at 01:38 #108024
Sidestick Priority
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Interesting discussion.
Would it be feasible to implement an optional user defined acceleration profile with a number of segments between 0 and max speed that can be adjusted and saved to a TT, to be imported by the sim as required?

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Delays after TRTS 18/05/2018 at 03:05 #108025
Chromatix
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Here's my take on the issue. As credentials, you might like to know that I've implemented some of the better physics models for Railworks DLCs - so I know what's what. Obviously SimSig warrants a much simplified model of train performance, but I think useful improvements can be made quite easily.

Fundamentally a train has a given weight, total power-at-rail, and peak total tractive effort. These three figures are readily available (at least approximately), and if considered alone, offer a reasonable approximation for acceleration curves on level track for modern types. Simply calculate the tractive effort corresponding to the rated power at the current speed, and if that's higher than the peak tractive effort rating, use the latter instead. Divide the tractive effort by the train weight to get acceleration. Just make sure your units are consistent.

To further improve this model, we should consider drag and gradient forces. Gradients (both up and down) simply subtract from (or add to) the calculated tractive effort proportionately to the weight of train on them and their steepness. Drag can be calculated as the square of the speed, scaled by a constant reflecting how streamlined the front of the train is, plus speed scaled by the train's weight to account for axlebox friction; subtract this sum from the available tractive effort. The net available tractive effort may be negative, in which case your train will lose speed.

Yet another improvement to the model comes if you add the "voltage limited speed". This is where the constant-power regime (tractive effort inversely proportional to speed) ends and is replaced by the constant-voltage regime (tractive effort inversely proportional to the *square* of the speed). For electric traction, often the constant-effort regime turns directly into the constant-voltage regime, which is why they appear to accelerate strongly to some speed and then rapidly taper off.

The above calculation raises the possibility that trains may actually stall on gradients. To avoid blocking the sim completely in such cases, I suggest treating the gradient function as zero below some minimal speed, eg. 5 mph. This will allow the train to creep up the hill and eventually clear the line.

Leaf-fall season requires also considering the "adhesive weight" of the train. For modern locomotive-hauled trains, that's simply the weight of the locomotive, assuming all axles are driven. Most multiple-unit trains have a proportion (<50%) of axles driven, eg. a 3-car Class 101 has four out of twelve, and you can estimate the adhesive weight from that. Choose an adhesion factor, and clamp the peak tractive effort to that factor multiplied by the adhesive weight.

So what about failures? Traction faults resulting in loss of power may occur in several ways, resulting in different combinations of modifications to the model parameters. The train weight remains the same in all cases.

Diesels may suffer casualty to the prime mover, eg. stuck injectors, ailing fuel pump, blown turbo, overheating. Steam locos may have bad coal, clinkered-up firegrate, clogged tubes. The result is a reduction in rated power.

Diesel-electrics and EMUs may lose weak-field. This alters their voltage-limited speed, so they still have full tractive effort and power at low speeds, but have less power above say 30-40 mph.

Diesel-electrics and electric traction may have isolated traction motors. This doesn't really affect rated power, but does reduce peak tractive effort and adhesive weight.

Diesel trains with multiple engines might suffer both power and effort disadvantages simultaneously from a common cause. Deltic is an exception, since both prime movers are wired into the same electric circuit. HSTs, double-headed trains, DMUs and the Type 4 diesel-hydraulics (which have one engine and one transmission per bogie) may simultaneously lose some fraction of both their power and tractive effort.

And, of course, we have the classic case of the entire loco failing and being substituted by one of lesser capabilities. A 'duff' being replaced by a 'ped' was especially common, and probably influenced those particular nicknames. For a less extreme example, replace a 2500hp '47' or 2700hp '50' with a 2000hp '40' or a 1750hp '37'. This is the only case in which the train weight does actually change.

To account for all the above, it's probably wise to simply list one or more complete sets of "degraded mode" performance data for the train type alongside the normal rating. The above guidelines should help TT authors to work out what adjustments are plausible for their trains. For common types, I could draw up a researched list of characteristics to crib from.

Last edited: 18/05/2018 at 03:12 by Chromatix
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Delays after TRTS 18/05/2018 at 12:58 #108034
58050
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Geoff if you are really interested in obtain figures of 'Power at Rail' Tractive Effort & also at what speeds each loco has a field divert & more I've got all this in upteen different official BR publications & drivers fault finding manuals. Also the same for some DMU & EMU classes. E-mail me or contact me on SKYPE if you are interested in looking at this type of data.
Last edited: 18/05/2018 at 12:58 by 58050
Reason: corrected spelling mistake

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Delays after TRTS 18/05/2018 at 14:04 #108035
58050
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The other thing not mentioned which also affects the way the train behaves is braking. There is a big difference between vacuum braked & air braked trains. Air braked trains tend to apply & release the brake much more rapidlythan vacuum braked stock. In all mainline diesel lcos of the BR era with the ecxception of Cl.56, Cl.58 & Cl60 loco inside the engine room was a rotatory switch with the option Air Pass/Vac Pass/Air Goods/Vac Goods. We always tended to leave the switch to either Air Pass or Vac Pass. That determined how fast the brakes would apply & release. Air brakes operate much faster than vacuum, but with the switch set to 'Pass' you get both compressors(Air) or both exhausters(vacuum) running at the same time providing the air or vacuum to apply the brakes & obviousluy replenish the system once the train brake valve was set to running or release. Whereas in the Goods option only one compressor or exhauster would be working. Even in 'Vac Pass' mode the brakes would take longer to release than in the train was air braked & THE SWITCH SET TO Air Pass. I've had experience with this several times driving the TPO or Newspaper trains as they were both vacuum braked stock during the mid 1980ss & once you'd slowed down & then started to run on clear signals very often you'd end up over-charging the brakes so they'd release a bit quicker, but that wasn't necessary on air braked stock as it was much more rapid.
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Delays after TRTS 18/05/2018 at 14:43 #108037
Chromatix
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Well, I deliberately left out any discussion of braking as it's less relevant to this particular game. However, there are a couple of effects that may be visible to the signalman:

1: After coupling a train together, it takes time to connect and charge the brake system, and prove its continuity. This is already accounted for in the coupling task timings.

2: Having applied brakes, it can take time to release them. This means that a train braking to a stand at a signal can't react instantly to it being pulled off, and will lose some more speed before being able to accelerate. The effect is minimal for modern multiple-unit trains (which have EP brakes), amounts to a few seconds' delay on air-braked passenger trains, and can be much more substantial on freight and vacuum-braked trains. especially if steam-hauled (as less pumping/exhausting capability is available). The delay for brake-piped trains is roughly proportional to train length; in general, releasing brakes after an emergency application also takes significantly longer than after a light or normal application.

3: To correct for the above point, drivers typically release the train brakes in advance of moving off, holding the train on the locomotive "straight air" brake instead; the latter takes only a second or two to release. This optimisation only applies if the driver has a reasonable expectation of moving off in the immediate future, so could be influenced by the "call back in X minutes" phone replies.

4: Trains equipped with WSP and/or sanders will be less affected by leaf-fall season in braking than those without; they can safely carry a bit more speed when approaching a known restriction.

Graphs showing real braking performance, including timing effects, are available in odd places. A simplified model could I think be worked out for SimSig without delving too deeply into the nasty details; just scale the train length by 0 for EP-braked trains, or some positive value for others, to obtain a brake release delay. Brake application delays are much less relevant to the game.

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Delays after TRTS 18/05/2018 at 16:53 #108043
58050
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Yes you are correct regarding the use of the straight air brake once the train has stopped. I can't ever re-call during my time on the footplate where the train brake & striaght air brake were used together apart from when passing out on the MP12(drivers course) when you'd say to the inspector I know you are supposed to leave the train brake applied when going onto the signal post telephone, so you'd leave the train brake in Initial & the Straight Air Brake on full. Once you had brought your train to a stand whether freight or passenger you usually put the straight air brake to maximum & release the train brake. As Chromatix says the straight air brake would release immeadiately & then you'd apply power to get the train moving.
On modern locos such as Cl.66/Cl.67 & Cl.70 as well as the Cl.59 those locos have Dopler radar systems which control the sheelslip on the traction motors to reduce wheel slip & it isn't as prevalent as it was on Cl.56 or Cl.58 locos when as soon as one axle slipped the power would immeadiately go to zero which resulted in severe lurching back & forth when on a wet rail or during leaf fall season.

Last edited: 18/05/2018 at 17:45 by 58050
Reason: corrected spelling error

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Delays after TRTS 18/05/2018 at 17:38 #108044
GeoffM
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Well I appreciate the insights but most of what has been said already happens in SimSig. I often wonder when we put features in like coasting instead of accelerating, only to brake a few seconds later, whether anybody notices!
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Delays after TRTS 18/05/2018 at 18:23 #108048
Peter Bennet
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A slightly different point, sometimes the unit used on a train is of higher spec than the train is diagramed for. For example, in the McSims quite often a 170 will go from a 100mph dash across the E&G to a train timed for a 156. So the train characteristics of the unit do not necessarily meet the requirements of the diagram. It was a conundrum when writing the timetables as to whether to set the train characteristics for the unit or the train, neither seemed quite right. Also, I presume that if a 170 is running late on a 156 timed path the driver will seek to recover time where permissible using the additional speed.

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Delays after TRTS 20/05/2018 at 05:02 #108105
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Quote:
I often wonder when we put features in like coasting instead of accelerating, only to brake a few seconds later, whether anybody notices!

Well, that sounds like something that would make very little difference to train timings, so it would only be noticeable to people who watch the Train List like a hawk. I'm sure it's a very nice little tweak, and such attention to detail is appreciated.

But when I *do* watch the Train List, I see things like trains slowing to 15mph on approach to the signal following one they passed at Yellow (a new Defensive Driving rule, apparently), and even if that signal cleared to Green minutes ago with a banner repeater on the way, the train only speeds up once it's actually passed the signal, not when it should be able to see that it's cleared. That makes a much bigger difference to timings, which are what *should* be visible to the player.

I also see HSTs running under Loss Of Power flag only being able to make 83mph, ie. two-thirds of their normal service speed. In reality they can comfortably make 100mph on one power car (actual speed capability with both power cars being somewhere north of 140mph), and probably more if they were allowed to. With a failed power car, their maximum speed is restricted for reasons of braking distance rather than power, since normally the brake pipe is vented from both ends while applying, but that can't happen if the multiple-working system is down. As a result, a LOP-afflicted HST makes much more of a mess in SimSig than it would in reality.

FWIW, with required power scaling roughly with the cube of speed (all else being equal), losing half power and tractive effort should still leave the train capable of about 80% of its normal speed, though it'll take longer to get there. Applying that simple rule to the HST's service speed happens to give 100mph, though that's actually a coincidence.

But many trains would tend to lose much less than half their power at a time - which is what I was trying to convey above - and in ways which don't necessarily affect their top speed at all, only their acceleration. So far as I can see, there's currently no way to set that up in SimSig.

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Delays after TRTS 20/05/2018 at 10:31 #108106
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The depth of knowledge (and the willingness to share it) among users of this Forum never ceases to amaze me. I really do enjoy picking up on all the new information and insights that I've found on the Forum over the years. I always used to think it was a sad day unless you had learnt something new until a friend reminded me it was an even sadder day if you hadn't managed to teach somebody something new.
“In life, there is always someone out there, who won’t like you, for whatever reason, don’t let the insecurities in their lives affect yours.” – Rashida Rowe
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Delays after TRTS 20/05/2018 at 12:22 #108109
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postal in post 108106 said:
I always used to think it was a sad day unless you had learnt something new until a friend reminded me it was an even sadder day if you hadn't managed to teach somebody something new.
You must have had a few smiles on your face in the past then, because on several occassions you have taught me something new.

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Delays after TRTS 20/05/2018 at 13:13 #108114
58050
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Chromatix states in an ealier post quote:-
I also see HSTs running under Loss Of Power flag only being able to make 83mph, ie. two-thirds of their normal service speed. In reality they can comfortably make 100mph on one power car (actual speed capability with both power cars being somewhere north of 140mph), and probably more if they were allowed to. With a failed power car, their maximum speed is restricted for reasons of braking distance rather than power, since normally the brake pipe is vented from both ends while applying, but that can't happen if the multiple-working system is down. As a result, a LOP-afflicted HST makes much more of a mess in SimSig than it would in reality.'

I definately don't agree with what he says here. I'd like what footplate experiewnce has he had & if so on what route? When I was on the footplate between 1985-1988 on the midland mainline HSTs running on 1 engine would probably at best erform like a type 4 diesel hauling 9 or 10 coaches. The midland mainline has some steep gradients which would be a challenge to an ECML?MML HST set with 8 Mk.3 coaches & a dead power car at the front or rear. RAIL H.P. AT CONT. RATING FULL ENGINE OUTPUT IS 1320KW. Now the other thing you need to remember that applying the ETS on a train drains that figure down. So on the Midland Mainline you'd be lucky if you got to 90mph with one power car running. Any loco fitted with ETH & has that switched on loses an percentage of power that the loco can apply to the traction motors. Maybe on the Great Western mainline a HST set running on 1 engine may make 100mph as that line is very flat except via the Berk & Hants route to Wesrtbury, but you can forget that on the Midland mainline or the ECML. Those of you who ever witness HSTs running or starting up at terminus's the reason why the rear power car is running at higher revs than the front one is because drivers always set the trains ETS off the rear power car & the reason for that is if that power shuts down for any reason the driver only has to reset the ETS to be provided from the power car he's driving from. Furthermore Cl.43 are Bo-Bo & as a result aren't as good as Co-Co in the sense of pulling power, but to compare a Cl.45+9 coaches or a Cl.47+9 coaches is similar to a HST set running on 1 power car is way out of reality So to say an HST would reach 100mph I've never seen or heard of it. I remember once speaking to a RES driver travelling to King's Cross to work a postal service north & the booked traction for the train was a Cl.67(Bo-Bo again) & I asked him f he was able to get to 100mph with his train over the ECML & he said not a prayer. He said even on full power you'd get in the ninetoes but you'd never get to 100mph unless you were travelling on a downhill gradient. When I was a loco controller Arsenal was playing a match at Old Trafford against Manchester United. There were a couple of special trains arranged to take supporters to the game. One train was booked to depart St. Pancras with a Cl.47/4+10 Mk.1 coaches & the other was booked to depart 10 minutes later from King's Cross, but with a Cl.67+10 Mk.1 coaches. Some of us on the power desks had a bet as to which of the 2 trains would reach Dore triangle first. My money was on the Cl.47 on the MML whereas other bet on the Cl.67 via the ECML to Doncaster & then towards Sheffield via Swinton with a slight higher speed & the linspeed being higher on the ECML. Well needless to say the Cl.47/4 off the MML got there before the Cl.67. There wasn't a massive difference in time something like 10 minutes.
Another anomaly with loco power output is that you can have other problems going on inside the engine room yet the power output is very good. On another occasion in 1986 hen Glendon North Junction (north of Kettering) was beuing re-modelled for Leicester PSB to take over I was booked on an engineering train as secondman. We arrived at Wellingborough by staff car & our loco was 47004(back then she was an Eastfield(ED) engine in BR blue livery). I did the driving that night & we had 44 vacuum braked 2 axle hopper wagons to collect spent ballast & spoil. However there were some fault lights in the engine room signalling High Water Temperature & Low Lub Oil, yet during the 8+ hours I drove her she was one of the best Cl.47 locos I've ever driven for giving power. We heard a few days later that she failed at Market Harborough with the Toton men that relieved us going back off site.

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Delays after TRTS 20/05/2018 at 20:42 #108126
Jan
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889 posts
Chromatix in post 108105 said:
But when I *do* watch the Train List, I see things like trains slowing to 15mph on approach to the signal following one they passed at Yellow (a new Defensive Driving rule, apparently), and even if that signal cleared to Green minutes ago with a banner repeater on the way, the train only speeds up once it's actually passed the signal, not when it should be able to see that it's cleared. That makes a much bigger difference to timings, which are what *should* be visible to the player.
Good find - it looks like unlike the default built-in rules, custom defensive driving rules don't properly account for a signal's sighting distance. Reported it as #20507 on Mantis.

Two million people attempt to use Birmingham's magnificent rail network every year, with just over a million of them managing to get further than Smethwick.
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Delays after TRTS 22/05/2018 at 07:05 #108135
jem771
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102 posts
Are there plans to put in features like coasting? I have noticed geoff's point.
slightly unrealistic for a train to acccelerate right up to its permissive speed only to slam on the anchors again.
approach control sigs are an example there.

Jezz
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