Class 47 Acceleration and Braking

[Taunton]

And no, an SD40-2 can't do 100mph (officially) but I suspect some used to get well into the 80s (at least) on hotshot freights in the past, before speed traps and radar speed guns became commonplace.

Certainly on the Santa Fe across the desert from Albuquerque to Barstow, in the 1970s-80s.

 

[SolomonSouth]

Not sure an 86 or 87 could be faster than a Taurus. If someone wants to arrange it.. I'll bring the timing gear along!!

Tbh they might be a similar pace

== Doublepost prevention - post automatically merged: 23 May 2021 ==

Sorry to wade in. But I drive 16x on a daily basis and I thought I'd hand over my thoughts/experiences.

The TSW/TSClassic 16x are far too quick off the mark, but braking is about right. For realistic performance, you should be able to knock 10-20mph (depending on the speed you're doing) off in step 2, back to step 1 and see it in, providing you know the route well enough. Of course, you won't know it properly but you'll know it enough for the game if you drive it there enough. I also have braking zones for good weather where you brake later and leave it in step 2 a lot longer and still stop comfortably.

Acceleration and overall performance- well, here's where it gets fun. Our 165s are more spritely and go a bit better. The difference between a 2/4car 165 and a 3/6 car 166, or a 5car 165/166 is noticeable. I'm not a fitter but I'd wager this is down to the 166's aircon and its tendancy to sap power at every opportunity.

A bad set you'll barely hit 90 all day. I can take sets to Cardiff and never get anywhere near the good 5-10nins you should be sat at 90. Others you'll hit 90 between Yatton and Nailsea, which in Turbo acceleration terms is a quite short distance!
I'd say a good set should do 0-90 in about 4-5minutes, a poor set likely around 7-8. Average it out between 5and7 minutes.
Notch 7 by 10mph or you'll never get anywhere.

0-40 performance is usually fairly good, it's the 40+ speeds where the gears change over you'll notice if it's a sluggish one.
That said, some of the worst you'll know by 10mph you're in for a slog of a trip!

Thanks for your thoughts! You don't need to apologise for wading in.
In TSW2, tractive effort starts falling away at 20mph. The class 166 does 0-60 in 65 seconds and 0-90 in 3.5 minutes
In TSW2020, the class 166 tractive effort falls away past 10mph. 0-60 in 93 secs. 0-90 in 5 ming 48.

So the TSW2020 performance is about right from what you're saying?

Again, I thought it was agreed 165 and 166 struggle to reach 90mph on a level track.

 

[hexagon789]

Woah... faster than a DB BR 182 Taurus

No idea tbh

Thanx for the info, I knew it was a far few (20 was a wild guess) as I can remember it took a age before the driver stopped notching !
It was great to be asked to watch the traction motor ammeter's and "shout if it goes in the red lad".

You can go in to the 'red' briefly, but the ammeter needles should be allowed to fall well back into the yellow section before any further taps are taken. I believe the later thyristor 90s & 91s microprocessors will not normally 'notch' (so to speak) into the red, do theoretically you might get better performance off an 87 say compared to a 90.

That particular journey was a 47/8.

Those awful things...

(Did not have a good reputation by all accounts compared to other 47 subclasses.)

 

[Cowley]

Those awful things...

(Did not have a good reputation by all accounts compared to other 47 subclasses.)

They weren’t awful as such, although they were pretty hammered by the end of their days.
They plucked all kinds of locos into the twin tank program and some were definitely better than others!
There were some pretty good locos in the 47/8 range though that had been well maintained up until then (ex Stratford ones for example).

 

[hexagon789]

They weren’t awful as such, although they were pretty hammered by the end of their days.
They plucked all kinds of locos into the twin tank program and some were definitely better than others!
There were some pretty good locos in the 47/8 range though that had been well maintained up until then (ex Stratford ones for example).

The higher ETS index also sapped power though. They were noted for unreliability, more so than any other subclass.

Though as with anything I don't doubt there's an element of pepetuated perception to that. Everyone says they are bad, so they are led to perceive them as bad - etc etc

 

[Richard Scott]

The higher ETS index also sapped power though. They were noted for unreliability, more so than any other subclass.

Though as with anything I don't doubt there's an element of pepetuated perception to that. Everyone says they are bad, so they are led to perceive them as bad - etc etc

47/8s were standard 66 ETH index if I remember correctly. A few locos were upgraded for sleeper trains; can't remember numbers off the top of my head but were something like 47671 onwards.

 

[Cowley]

47/8s were standard 66 ETH index if I remember correctly. A few locos were upgraded for sleeper trains; can't remember numbers off the top of my head but we're something like 47671 onwards.

Yes, I can just about remember them in old money - 47616, 562, 586, 593, 595 and 617. All good well thought of Scottish machines apart from 616 from what I remember.

 

[hexagon789]

47/8s were standard 66 ETH index if I remember correctly. A few locos were upgraded for sleeper trains; can't remember numbers off the top of my head but we're something like 47671 onwards.

I must be thinking of something else or I'm confusing them with something.

 

[47827]

47/8s were generally not all that bad. I've enough miles on them to speak with some sort of authority and knew enough crews who drove them. Crewe's maintenance on them was a bit hit and miss and a small number of them had spells of being awful - plus one year at Crewe there was an oil contamination issue I seem to recall. Some diagrams were 800-900 miles in the final years of XC and they weren't even the turns that the most failures arose on. Most failures were at the prep stage at places like Saltley and not so many "en route" failures. Always worth looking at loco shortages in context. 47/8s were frequently called upon to cover for 86s, HSTs (both dragging and with hauled sets) and occasionally 158s plus dragging electric traction via diversionary routes. I've probably had no more than 8 to 10 complete en route (between station) failures in 10,000s of journeys over a decade or so on the XC fleet. Others were loco swaps en route or before departure owing to faults and even then probably only in the dozens of times.

I would say the Great Western Fleet in the last few years were probably among the more solid performers too, especially when most of the small fleet was needed some days to run the daytime trains that ran again around about 1999-2002 (especially if 57601 was not available for its weekday turns off Laira). I only recall experiencing 1 single complete loss of power failure en route (47830 on the evening sleeper in rural Cornwall). Virtually no other failures with the GW fleet even en route in many hundreds of journeys.

There is often the perception they were very unreliable (and they are compared to some modern trains) as focus tends to be on when they've failed and what's replaced one, even though many of the exotic classes to be sent out where on days 47/8s were out covering for other things too, or failure faults were minor technical issues that caused prep failure (everything from windscreen wipers to cab heaters or stiff cab doors that need a kick to open).

The RES/EWS 47 fleet was less reliable over that era (certainly on mail trains and charters). Possibly goes back to having Crewe as the base, not as well looked after as the 47/8s and the culture among "some" of the drivers who worked them sometimes not being as interested in keeping the job going as much as many of the XC drivers.

 

[SolomonSouth]

No idea tbh



You can go in to the 'red' briefly, but the ammeter needles should be allowed to fall well back into the yellow section before any further taps are taken. I believe the later thyristor 90s & 91s microprocessors will not normally 'notch' (so to speak) into the red, do theoretically you might get better performance off an 87 say compared to a 90.


Those awful things...

(Did not have a good reputation by all accounts compared to other 47 subclasses.)

47s? Unreliable? No they must be reliable or they wouldn't build 512 of them, BREL aren't dumb
Imagine the maintenance cost of 512 unreliable locos
Therefore they must be very reliable, they wouldn't even build loads of an unreliable design in the first place

 

[43096]

47s? Unreliable? No they must be reliable or they wouldn't build 512 of them, BREL aren't dumb
Imagine the maintenance cost of 512 unreliable locos
Therefore they must be very reliable, they wouldn't even build loads of an unreliable design in the first place

They have never been that reliable - they were permanently de-rated from 2750hp within a few years of being built. Obviously they didn’t think they would be unreliable otherwise they wouldn’t have built them, but the problems didn’t become apparent immediately. Essentially BR learned to live with them as they couldn’t afford to re-engineer them, either. Duff by name, duff by nature...

Oh and BREL didn’t exist when they were built. They were built by Brush and Crewe Works. Crewe at the time was a BR works as BREL didn’t come into being until the early 1970s.

 

[Ghawk2005]

Sorry to wade in. But I drive 16x on a daily basis and I thought I'd hand over my thoughts/experiences.

The TSW/TSClassic 16x are far too quick off the mark, but braking is about right. For realistic performance, you should be able to knock 10-20mph (depending on the speed you're doing) off in step 2, back to step 1 and see it in, providing you know the route well enough. Of course, you won't know it properly but you'll know it enough for the game if you drive it there enough. I also have braking zones for good weather where you brake later and leave it in step 2 a lot longer and still stop comfortably.

Acceleration and overall performance- well, here's where it gets fun. Our 165s are more spritely and go a bit better. The difference between a 2/4car 165 and a 3/6 car 166, or a 5car 165/166 is noticeable. I'm not a fitter but I'd wager this is down to the 166's aircon and its tendancy to sap power at every opportunity.

A bad set you'll barely hit 90 all day. I can take sets to Cardiff and never get anywhere near the good 5-10nins you should be sat at 90. Others you'll hit 90 between Yatton and Nailsea, which in Turbo acceleration terms is a quite short distance!
I'd say a good set should do 0-90 in about 4-5minutes, a poor set likely around 7-8. Average it out between 5and7 minutes.
Notch 7 by 10mph or you'll never get anywhere.

0-40 performance is usually fairly good, it's the 40+ speeds where the gears change over you'll notice if it's a sluggish one.
That said, some of the worst you'll know by 10mph you're in for a slog of a trip!

Please don’t apologise. Your input is very much appreciated. thank you!

 

[SolomonSouth]

They have never been that reliable - they were permanently de-rated from 2750hp within a few years of being built. Obviously they didn’t think they would be unreliable otherwise they wouldn’t have built them, but the problems didn’t become apparent immediately. Essentially BR learned to live with them as they couldn’t afford to re-engineer them, either. Duff by name, duff by nature...

Oh and BREL didn’t exist when they were built. They were built by Brush and Crewe Works. Crewe at the time was a BR works as BREL didn’t come into being until the early 1970s.

Oh it was brush? Thx mate! So the problems didn't become apprent immediately. I see.
It would be fascinating to know how quickly they would have accelerated pre-detune, they would have been absolute rockets.

Please don’t apologise. Your input is very much appreciated. thank you!

I know, very knowledgeable and nice to know even irl the 166 is good to 40mph. So its not entirely trash at accelerating. Also fascinating to know 165s go a bit better than 166s

 

[Richard Scott]

47s? Unreliable? No they must be reliable or they wouldn't build 512 of them, BREL aren't dumb
Imagine the maintenance cost of 512 unreliable locos
Therefore they must be very reliable, they wouldn't even build loads of an unreliable design in the first place

Interestingly the younger Brush equipped 46s were withdrawn long before the older Crompton Parkinson equipped 45s. I know some 45s were withdrawn before some 46s but by the time the 46s were all withdrawn majority of 45s were still in traffic. A 47 isn't too disimilar mechanically to a 46. Just some food for thought, maybe sheer numbers were on the side of the 47s?

 

[Railperf]

Interestingly the younger Brush equipped 46s were withdrawn long before the older Crompton Parkinson equipped 45s. I know some 45s were withdrawn before some 46s but by the time the 46s were all withdrawn majority of 45s were still in traffic. A 47 isn't too disimilar mechanically to a 46. Just some food for thought, maybe sheer numbers were on the side of the 47s?

Mechanically similar but the 47 performance was in a different league.
I recall reading an article comparing 47s and the much lauded 55 Deltics. IIRC the 47s were not embarrased in any way.

 

[SolomonSouth]

Mechanically similar but the 47 performance was in a different league.
I recall reading an article comparing 47s and the much lauded 55 Deltics. IIRC the 47s were not embarrased in any way.

Deltic does have a higher top speed than a 47

 

[Steve Harris]

Deltic does have a higher top speed than a 47

I think we are talking about pulling away from a station stop here !! Hence the "were not embarrassed in any way" comment kind of eludes to that.

 

[SolomonSouth]

I think we are talking about pulling away from a station stop here !! Hence the "were not embarrassed in any way" comment kind of eludes to that.

Deltic does also have more power than a 47 tho (3300 vs 2500)

 

[Richard Scott]

Mechanically similar but the 47 performance was in a different league.
I recall reading an article comparing 47s and the much lauded 55 Deltics. IIRC the 47s were not embarrased in any way.

Maybe compared to a 46 but a 45 could easily hold its own against a 47 due to its more sophisticated electrical systems. Five stages of field diversion in the 45 gave it the edge on acceleration and no point mentioning too much about weight as a 45/1 only 13 tons heavier than a 47/4 so pretty negligible.

 

[Cowley]

Maybe compared to a 46 but a 45 could easily hold its own against a 47 due to its more sophisticated electrical systems. Five stages of field diversion in the 45 gave it the edge on acceleration and no point mentioning too much about weight as a 45/1 only 13 tons heavier than a 47/4 so pretty negligible.

Yep. Pretty quick machines back in the day and good for a ton if pushed too...

 

[Steve Harris]

Deltic does also have more power than a 47 tho (3300 vs 2500)

But power and top speed isn't everthing.

For instance, If you have a 2 parallel railway tracks, both have a line speed of 90mph, a Class 55 with no sanding equipment and a Class 47 with sanding equipment on a rainy day, which one would win a race between the 2 ??

I think you would get a surprise !

Car racing is similar (less powerful cars win due to better handling, more stable braking, better tyres, less weight etc), having the most horsepower doesn't always mean you win. It's how you can use that power which determines if you win or not.

 

[SolomonSouth]

Maybe compared to a 46 but a 45 could easily hold its own against a 47 due to its more sophisticated electrical systems. Five stages of field diversion in the 45 gave it the edge on acceleration and no point mentioning too much about weight as a 45/1 only 13 tons heavier than a 47/4 so pretty negligible.

Oh ok. 45 and 47 accelerate the same in TSW2 so its feasible it could be the same IRL.

But power and top speed isn't everthing.

For instance, If you have a 2 parallel railway tracks, both have a line speed of 90mph, a Class 55 with no sanding equipment and a Class 47 with sanding equipment on a rainy day, which one would win a race between the 2 ??

I think you would get a surprise !

Car racing is similar (less powerful cars win due to better handling, more stable braking, better tyres, less weight etc), having the most horsepower doesn't always mean you win. It's how you can use that power which determines if you win or not.

Does the class 55 overload amps easily or something?
Also I wonder how a 66 compares to a 47.

 

[Steve Harris]

Oh ok. 45 and 47 accelerate the same in TSW2 so its feasible it could be the same IRL.

Does the class 55 overload amps easily or something?
Also I wonder how a 66 compares to a 47.

Have you tried researching that question ?

 

[SolomonSouth]

Have you tried researching that question ?

Oh.... I've just found something. I was researching it trying to find something and found this: https://www.kentrail.org.uk/Class 66.htm
The article says 0-60 in 23 secs. Interesting how it also says the engine cuts out at 77mph automatically - is this to avoid overheating? Presumably

 

[hwl]

the engine cuts out at 77mph automatically - is this to avoid overheating? Presumably

Or that they are limited to 75mph...
Brakes applying at 80 is the other subtle hint.

 

[SolomonSouth]

Or that they are limited to 75mph...
Brakes applying at 80 is the other subtle hint.

Yeah

 

[Steve Harris]

Or that they are limited to 75mph...
Brakes applying at 80 is the other subtle hint.

Indeed.

I think SolomonSouth may be a youngster, as I have noticed that the yoof of today seem to get taught always ask first, rather than getting taught to research first and if unsure, then ask (which is the way I got taught and can be rather more productive than the "modern" way).

I'm sure posters on here will help @SolomonSouth but a friendly word of advice Solomon, read what I have posted above as some people will get tired of a barrage of constant questions.

 

[SolomonSouth]

Indeed.

I think SolomonSouth may be a youngster, as I have noticed that the yoof of today seem to get taught always ask first, rather than getting taught to research first and if unsure, then ask (which is the way I got taught and can be rather more productive than the "modern" way).

I'm sure posters on here will help @SolomonSouth but a friendly word of advice Solomon, read what I have posted above as some people will get tired of a barrage of constant questions.

Thanks steve. I'm actually 15 so yeah I'm a youngster

 

[Richard Scott]

Thanks steve. I'm actually 15 so yeah I'm a youngster

But don't stop asking questions if you can't find the answers!

 

[SolomonSouth]

But don't stop asking questions if you can't find the answers!

I know Richard