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Max speed...

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Sean Emmett

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Flaman recorders were fitted to the Gresley A4s.

I have been timing trains for nearly 40 years and have recorded a few notable overspeeds, 117 mph (100 limit) with a class 442 at Shawford and 111 mph (95 loco limit) with a class 47 down Madeley bank spring readily to mind. A 4VEP at 80 mph through Twickenham (60 limit) was lively, in the course of recording an even time run between Ascot and Richmond. As for mainline steam...

Much rarer now, but in the early days of the IETs some drivers had difficulty in reining them in, especially when going over summits. A trip over Wrangaton (between Totnes and Plymouth) reached 68 after clearing the summit around the regulation 60, before a stiff brake application to get speed below 60. A couple of others with IETs were 108 vice 100 between Taunton and Bridgwater (twice, accelerated to 108, braked to 100 then slowly accelerated to 108 again), and 78 vice 70 between Ledbury and Hereford.

I use a Garmin GPS 78csx (about 10 years old) for spot speeds, and take passing times from the infrastructure (stations, bridges, crossings) and enter them into a spreadsheet to check average speeds. The GPS unit also records a track log for later analysis, which can be processed to remove obvious spikes e.g. entering and leaving tunnels, etc. Before that i used the mileposts, with all the problems of their visibility and accuracy.

Amusingly, GWR issued a cab ride video during the first lockdown, which appeared to show 131 mph on the descent to Little Somerford.

Unless a train had found its balancing speed on a gradient, I quote speeds to the nearest whole mph, tending to round down rather than up, as I don't think I can claim greater accuracy than that.

Sean
 
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scragend

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What year did you leave primary school? We never got taught anything like that

60 mph is 1 mile per minute
1 mile is 5280 feet (1760 yards)
5280 feet per minute = 88 feet per second

It doesn't matter what the units are, it's just maths!
 

Taunton

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Conversely however, if the record showed that a [French] driver had managed to recover time following a delay outwith his control, but without exceeding the loco or line speed limits, he would receive a corresponding financial bonus. All this made for a very careful and professional driving technique which was much admired by other railways around the world.
Sometimes. The payment of a bonus for recovering time seems to have been a uniquely French approach. It really came to the fore for overnight sleeper trains on the day in Spring when the clocks go forward. Drivers would attempt to recover as much of the 60 minutes as possible by morning. Back in the sleepers, which were normally timed somewhat sedately for comfort, very little sleep became possible round the curves and over pointwork.
 

LNW-GW Joint

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I know this has often been touted but I've yet to see ot mentioned in print. To say nothing of the fact it would require the cab signalling to be able to be somehow modified to allow a higher speed in such circumstances, as going over the limit would trigger a brake application. The French TVM will allow a 15km/h margin at high-speeds, the German LZB allows nothing, and indeed in articles references the ICE trains it was noted how the train always kept 2-3km/h below the limit.
For what it's worth, I was on a TI Frecciarossa train last week Turin-Milan, and again Milan-Bologna on the Italian AV lines rated at 300km/h (under ETCS).
The train's on-line moving map feed showed mostly 297-298km/h, though it did once touch the 300.
Presumably the on-line feed is more accurate than a smartphone GPS measurement.
The terrain is of course mostly bone-flat across the Po plain.
 
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hexagon789

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From 1901 onwards, a large number of French locomotives - steam included - were fitted with M. Flaman's patent speed recorders. These were highly accurate devices driven by a spool from one of the axles and recorded on a roll of graph paper not only the loco's speed at any given time, but also the level of driver vigilance by recording the time taken for the driver to react to the various automatic warning devices used over the years. The device was first patented in 1901 and by the outbreak of the first world war about 80% of French locomotives were fitted with them. They were first used by the Nord, Est, Etat and Paris-Lyon-Mediterranee companies, but following nationalisation in 1938 they were quickly adopted as standard by SNCF. The driver would hand in his recording roll(s) with his timesheet at the end of each shift and any overspeed - or loss of time caused by the driver would result in money being deducted from his pay packet. Conversely however, if the record showed that a driver had managed to recover time following a delay outwith his control, but without exceeding the loco or line speed limits, he would receive a corresponding financial bonus. All this made for a very careful and professional driving technique which was much admired by other railways around the world. Many other railways in different countries subsequently adopted the Flaman recorder, including some in Australia. I believe that the Germanic countries of Northern and Central Europe preferred the Swiss-made Hasler recorders - as also used for many years by CIE/Iarnroid Eireann - but I'm not certain whether these were suitable for use on steam locos. Someone on here will probably know!
The widespread use of speed recorders and the various bonus and deductions certainly seems to have made French drivers very disciplined. Even today, they are the leaders in defence driving - as soon as even a whiff of a cautionary aspect is sighted - in goes the brake.

No (Southern) Irish steam locos had speedometers except the GSR B1a/800 Class trio. No idea about Northern Ireland.

For what it's worth, I was on a TI Frecciarossa train last week Turin-Milan, and again Milan-Bologna on the Italian AV lines rated at 300km/h (under ETCS).
The train's on-line moving map feed showed mostly 297-298km/h, though it did once touch the 300.
Presumably the on-line feed is more accurate than a smartphone GPS measurement.
I doubt it, one trip on a Venice-Padua-Bologna-Florence-Rome saw us supposedly touch 397 and at various other times well over the 300 mark but never for more than a few seconds before recovering to more realistic figures of 240-245. This was on a Frecciargento train limited to 250km/h.
 

contrex

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What year did you leave primary school? We never got taught anything like that
I started primary school (infants) in 1957, and left (juniors) in 1963. I distinctly remember Mr Jones tapping each word out on his desk with a ruler 'Sixty miles per hour is eighty eight feet per second'. We all had to say it with him, and do exercises like how many yards do you go in two minutes at 80 miles an hour. I was in his class aged 10. Even if he hadn't, it is pretty obvious that 60 miles an hour is a mile a minute, and 5280 feet in a mile divided by 60 is a very easy division sum for 10 year olds, surely? (you can just knock the noughts off if you want) If you forgot how many feet in a yard, and yards in a mile, etc (which we had drummed into us) there were tables printed on the back cover of our exercise books.
 

Saj8

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We had a new operational notice on GWR today that one of the "features" of the new TMS update is that the speed limiter is now not able to be switched off, and will be set at 125mph, with the driver able to select a lower speed. As the speed limiter limits the train speed to 1mph less than the set speed, that means that GWR's IETs are now 124mph max. Of course, with the speed limiter receiving its feed from the GPS and the speedo being referenced to wheel rotations, the indicated speed will be anywhere between around 120 - 128mph on the speedo, depending on how worn the tyres are. I was once driving a set with the limiter set to 125mph (so 124 in reality) and the wheels were worn enough to make the ATP warble at an indicated 128mph!
 

snowball

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We had a new operational notice on GWR today that one of the "features" of the new TMS update is that the speed limiter is now not able to be switched off, and will be set at 125mph, with the driver able to select a lower speed. As the speed limiter limits the train speed to 1mph less than the set speed, that means that GWR's IETs are now 124mph max. Of course, with the speed limiter receiving its feed from the GPS and the speedo being referenced to wheel rotations, the indicated speed will be anywhere between around 120 - 128mph on the speedo, depending on how worn the tyres are. I was once driving a set with the limiter set to 125mph (so 124 in reality) and the wheels were worn enough to make the ATP warble at an indicated 128mph!
This has its own thread under Traction and Rolling Stock.
 

hexagon789

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We had a new operational notice on GWR today that one of the "features" of the new TMS update is that the speed limiter is now not able to be switched off, and will be set at 125mph, with the driver able to select a lower speed. As the speed limiter limits the train speed to 1mph less than the set speed, that means that GWR's IETs are now 124mph max. Of course, with the speed limiter receiving its feed from the GPS and the speedo being referenced to wheel rotations, the indicated speed will be anywhere between around 120 - 128mph on the speedo, depending on how worn the tyres are. I was once driving a set with the limiter set to 125mph (so 124 in reality) and the wheels were worn enough to make the ATP warble at an indicated 128mph!
Already being discussed here:
 

matchmaker

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The semaphore signalling on the Eastern side was the reason that Edinburgh-Polmont remained denoted in the Sectional Appendix as "75mph max (except Glasgow-Edinburgh High Speed Trains - 90mph) until the 1979 revision - presumably it was resignalled to colour lights by then.

The Western side (Polmont-Glasgow) intriguingly was 100 max, rather than merely 90, even though no traction was officially capable of such until the HSTs appeared on certain workings beginning in 1981 with the Sundays Only 0945 GLQ-KGX.
The push pull sets were signalled in the AB areas (Greenhill Upper to Haymarket Central, although Linlithgow - Winchburgh Junction and Queensferry Junction to Saughton Junction were TCB, using I think bells rather than describers) as 4-4. A system of double blocking was used whereby as soon as a 4-4 was accepted it was immediately offered on to the next box, instead of waiting for the entering section. The (outer) distants were all colour light in the semaphore signalled areas by this time (any inner distants, such as Bo'ness Junction, remained semaphore). Some quite short sections - Polmont - Bo'ness was just over 2 miles.
 

hexagon789

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The push pull sets were signalled in the AB areas (Greenhill Upper to Haymarket Central, although Linlithgow - Winchburgh Junction and Queensferry Junction to Saughton Junction were TCB, using I think bells rather than describers) as 4-4. A system of double blocking was used whereby as soon as a 4-4 was accepted it was immediately offered on to the next box, instead of waiting for the entering section. The (outer) distants were all colour light in the semaphore signalled areas by this time (any inner distants, such as Bo'ness Junction, remained semaphore). Some quite short sections - Polmont - Bo'ness was just over 2 miles.
I assumed that it was the two-stage disc air-braking allowed the sets to stop from 90 in the same distance a conventional tread braked vacuum train could from 75
 

peteb

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If you have a decent watch with stopwatch function, or can set a stopwatch on your phone, then 900 divided by the number of seconds for a quarter mile equals the speed, so 15 seconds = 60mph. Provided there are quarter mile posts to be seen and you are reasonably quick witted you can always tell the speed of a train in daylight hours. Mind you a slight error (human) could cock up the result significantly......however most speeding data is curiously absent from most magazine performance logs to protect the train crew I assume...? With virtually everyone having access to a phone with video capability the probability is that any long distance heroic speeds are likely to be recorded, only those momentary lapses are likely to escape censure.
 
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6Gman

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Most GPS units are accurate to +/- 1%

If you have a train running at 125mph plus the possible 3mph over, i.e. 128mph, adding 1% on to that gives 129.8mph which is very close to 131mph; so the GPS doesn't even need to be faulty to display 130mph and an extra 1mph is easily explained by the signal getting slightly interefered with - trees are a frequent culprit, as are tall buildings. A reflected GPS signal can confuse the receiving unit.
I have to say that whenever I've tried to use my GPS on a Pendolino it's simply refused to work so I can believe there can be issues!
 

GC class B1

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My iPhone gps speedometer is pretty good on class 800 on great western, as it shows a steady speed and doesn’t go above 124 MPH, but doesn’t work at all on voyagers or meridians as it can’t see the satellites. I have noticed a variable reading on one class of vehicles a few weeks ago, but I can’t remember which it was, I think it was a Hull trains Class 800. I suspect that the weather is a factor with satellite visivilify.
 

peteb

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GPS seems fairly accurate in a car, my passenger and I tried it out with them generally reading 1-2mph below my speedo reading. I have heard that all car speedos are a little optimistic, wonder why? On trains my gps works if phone is right against a window but not good otherwise.
 

JamesT

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GPS seems fairly accurate in a car, my passenger and I tried it out with them generally reading 1-2mph below my speedo reading. I have heard that all car speedos are a little optimistic, wonder why? On trains my gps works if phone is right against a window but not good otherwise.
The law on speedometers in cars requires them to never under read the speed so a driver can’t claim they were doing the limit according to their speedo but were actually going faster. Hence the manufacturers will make them read slightly optimistically as it generally doesn’t matter if you think you’re doing 70 when it’s actually 68.
 

peteb

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The law on speedometers in cars requires them to never under read the speed so a driver can’t claim they were doing the limit according to their speedo but were actually going faster. Hence the manufacturers will make them read slightly optimistically as it generally doesn’t matter if you think you’re doing 70 when it’s actually 68.
Ah interesting
 

DarloRich

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I think the medals go to the LNER and TPE drivers who reached 140. Plus all the drivers that initially trained 390’s that got them upto 140 as part of the training. Then there’s all the drivers that drive hst’s pre data recorders.
But other than that I guess you won.
they had them fancy modern electric trains. @43066 suggests he done it a 1970's lump powered by a submarine engine! Winner.

OFFICAL ANNOUCEMENT: In no way does RUK encourage or support such dangerous risk taking. It is not big, it isn't clever and it costs a fortune in diesel and lubrication oil.
 

matchmaker

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I assumed that it was the two-stage disc air-braking allowed the sets to stop from 90 in the same distance a conventional tread braked vacuum train could from 75
From "One at each end" by Nick Lawford;

"Detailed planning of a more practical nature started in Glasgow in 1968. Using a basic definition of 90 mph operation, rolling stock of minimum contemporary Mk.2 interior standard, a 30 minute interval service Glasgow Queen Street to Edinburgh Waverley was set, alternating non-stop to Haymarket and one intermediate call at Falkirk High. Routine permanent way renewal had already upgraded track standard (but not line limits) to 90 or 100 mph. There were no significant grades except for the 1 in 45 incline out of Glasgow Queen St to Cowlairs. The main limitation on route speed was on signalling. At the time 75 mph was blanket maximum speed in Scotland and resignalling was necessary to increase braking distances to allow 90 mph running. £ 600,000 was allocated to Cadder - Greenhill Jn - Falkirk area resignalling and just £ 200,000 for track work."

That resignalling was mainly at the western end - an NX panel in Cadder signalbox replaced all the conventional boxes between Cowlairs and Greenhill Upper. I don't know if much was done at the eastern end - possibly the distants were moved further out. The disc braking will certainly have improved stopping distances. These Mk 2s were the first loco hauled stock to be disc braked, as I understand it.
 

Efini92

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they had them fancy modern electric trains. @43066 suggests he done it a 1970's lump powered by a submarine engine! Winner.

OFFICAL ANNOUCEMENT: In no way does RUK encourage or support such dangerous risk taking. It is not big, it isn't clever and it costs a fortune in diesel and lubrication oil.
The lumps powering @43066 were more modern. Plus there was no mention of the ATP that achieved 160
 

Bald Rick

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I believe that on European high speed lines, higher speeds are permissible which are only used to recover late running, than are used in normal service. I suspect in this country, such a resilient capability which prevents people from missing connections would be dismissed as “gold plating”

typical French practice is to time services to operate at lower than linespeed, such that drivers Are often expected to travel at below linespeed, but can come up to linespeed to reviver minor delay.
 

Rheoman

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Another factor that stops a class 390 from high end over speeding is a software mod implemented some years back. Once you get to 125 mph the power starts to decrease and by the time you are doing 127 mph there is zero tractive effort being applied. The only way you will exceed 128 mph is on a very steep gradient or a dodgy speedo. The TASS would start shouting at 128 anyway and dump the brakes at 131 mph
 

43066

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Another factor that stops a class 390 from high end over speeding is a software mod implemented some years back. Once you get to 125 mph the power starts to decrease and by the time you are doing 127 mph there is zero tractive effort being applied. The only way you will exceed 128 mph is on a very steep gradient or a dodgy speedo. The TASS would start shouting at 128 anyway and dump the brakes at 131 mph

That’s a brave profile picture!
 

trebor79

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An inaccurate reading on your GPS is much more likely. It's also worth noting that 99.9% of drivers are highly professional people who wouldn't dream of speeding (and putting their career on the line) to make up time.
It certainly used to happen. Probably not any more withthe various monitoring and speed control systems, and the black box which will reveal any naughtiness if downloaded.
 
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