City of Truro's speed record

[Jamie]

Some of the malice directed at Nick would be better written in invisible ink TBPH.

[beast66606]

I think this thread amply demonstrates the glass half empty approach so prevalent in this country. As has been pointed out above any error need not have necessarily been on the minus side - the thing could actually have been doing 105mph...

 

That was my point Phil (as you obviously surmised), I wasn't supporting or denying the 102 claim, merely pointing out that a small error + or - would yield a significantly different speed.

 

In these situations we will never actually know, there is no-one alive who was there, we only have the writings from the day so they can either be taken as correct, or not - but neither 100% proves, or disproves, the claim, so imho we might as well accept what was said at the time.

[PhilH]

What I don't think can be in dispute is that it must have been by degrees exhilarating, terrifying and above all so satisfying to have been on the footplate that day.

[coachmann]

Debunking history is a popular TV pastime, as it sells! Afterall it is no used screening a documentary when everyone knows the tale off by heart. TV has to introduce a slant like "Custers Last Stand......WHY...?" "Did his mum run off with a Blackfoot?...... Did he have Deli Belly? ........Was his suit made by Cohens?". Todays presenters are ex actors (celebs) who present everything from the secret life of pavements to the golden age of damp cloths. Folk now question everything.

 

So did City of Truro do over 100mph? I was born 38 years after the event so who am I to question it? Records tell us the GWR was street ahead of the other companies...... It had the boilers capable of supplying steam enough for fast runs, long lap long travel valves, ample bearings and engineering second to none. Remember this was 1904 when the Midland was still running its express trains double headed and the LNWR had just built its first unsuperheated Precursor 4-4-0.

[Butler Henderson]

The Midland were still running double headed when 4472 did 100

[asmay2002]

The two later efforts listed above were generally thought to be irrefutable at the time as they were measured using the dynamometer car, which is positively archaic by todays standards.

 

The point about Mallard's speed is not that it was measured by a dynamometer car but that there were 3 independent separate sets of recordings. In addition to the dynamometer car there was the Flaman recorder on the loco AND chaps with stopwatches in the train (including C J Allen). The highest speed recorded was for a brief period on the Flaman recorder trace (a matter of yards) with both the stopwatch chaps and the dynamometer car giving lower numbers. Given three separate recordings Gresley's claim for 125mph was safe.

 

City of Truro's claim was recorded by 1 individual and unverified by either another timer with a watch or any other device. That of itself doesn't make it wrong - just uncorroborated.

[Peter Kazmierczak]

The point about Mallard's speed is not that it was measured by a dynamometer car but that there were 3 independent separate sets of recordings. In addition to the dynamometer car there was the Flaman recorder on the loco AND chaps with stopwatches in the train (including C J Allen). The highest speed recorded was for a brief period on the Flaman recorder trace (a matter of yards) with both the stopwatch chaps and the dynamometer car giving lower numbers. Given three separate recordings Gresley's claim for 125mph was safe.

 

 

 

Being slightly pedantic, C J Allen wasn't on Mallard's record run. He'd been invited, but was unable to attend. Bet he wished he'd changed his plans, but there was a deal of secrecy around this run so even that famous train-timer wasn't in the know.

 

The recording by the dynamometer car would've been the only reliable record. I wouldn't trust speedometers on locos.

[roythebus]

I suppose the analogy here could be the modern questioning of the centuries old belief that the earth was made in seven days and that it is flat.

[coachmann]

City of Truro's claim was recorded by 1 individual and unverified by either another timer with a watch or any other device. That of itself doesn't make it wrong - just uncorroborated.

 

The GWR, mindful of its safety record, kept the feat quiet and it did not appear in the main press or Railway Magazine. However it was published in a local newspaper, as a second person had also recorded the speed, but i think the identity of the loco was kept quiet. Full details came out a few years later.

[RJS1977]

I suppose the analogy here could be the modern questioning of the centuries old belief that the earth was made in seven days and that it is flat.

 

They're actually two completely different beliefs.... Contrary to what the media would probably tell you, throughout most of the Christian era it has been generally accepted that the earth is round - this didn't start with Gallileo & Columbus.

 

However, you do make a valid point in that ultimately nobody can conclusively prove anything that happened in the past without making certain assumptions that may or may not be shown to be incorrect at some future date, whether that be assuming that Rous-Marten's timings were accurate, or assuming that rocks are always formed with the same ratios of certain radioctive isotopes.

[The Stationmaster]

The GWR, mindful of its safety record, kept the feat quiet and it did not appear in the main press or Railway Magazine. However it was published in a local newspaper, as a second person had also recorded the speed, but i think the identity of the loco was kept quiet. Full details came out a few years later.

And not just that of course but there were public concerns about trains 'racing up from Plymouth' and the GWR clearly didn't want to add any fuel to those fires - even tho' its trains were not conveying passengers.

 

That apart I'm saying little - we have a contemporary record of events from an experienced timer who knew the route quite well and we know that 'fast running' (whatever that might mean) was the order of the day for the Ocean Mails trains hence the presence of Footplate Inspectors and we also know from records of other trains that some very fast running was taking place regularly both west and east of the Bristol loco change. The only debate then is down to the accuracy with which Rous Marten used his stopwatch or watches and that has already been explored.

[RJS1977]

...but back on topic (from me):

 

- Truro's speed wasn't a point speed, it was measured over quarter of a mile, during which the loco was still accelerating (Driver Clements closed the regulator and jammed the brakes on almost immediately after the mile post). So if the 102.3mph was accurate for the quarter mile, then 3440 was doing more than that at the time it passed the post. Likewise, if 3440 averaged less than 102.3 over the quarter mile it could well have still been doing more than 100 as it passed the post, even if it didn't average it over the whole section.

 

At around the time of the centenary run, I did some rough calculations regarding the acceleration required for 3440 to have done 100mph at the bottom of the bank from 80mph at Whiteball, allowing for possible errors in mileposts etc, and found that said acceleration was comparable to the component of the acceleration due to gravity down the bank. In other words, all Truro had to do was overcome friction and wind resistance and gravity would do the rest.

 

I also re-created the formation of the train on Microsoft Train Simulator a while back and re-created the run from Plymouth, hitting 80mph at the exit of Whiteball as recorded by Rous-Marten. With the regulator wide open, my speed at the bottom was.... 102mph! Now, of course this assumes that the simulation is accurate but the two factors together suggest to me that 3440 was at the very least capable of such a speed and as such I see no real reason to dispute the figure.

 

That said, there are several locos with prior claims of 100mph running, including this one in the Chicago Science Museum:

 

http://i1268.photobu...5_6585204_n.jpg

 

(apologies for camera shake).

[newbryford]

At the risk of being severely tortured and very

 

Surely the only way that kettles can do 100 plus is vertically downwards..............

 

Cheers,

Mick

[Peter Kazmierczak]

And a word from O S Nock, another leading train-timer, in his book "Speed Records on Britain's Railways" published in 1971.

 

He attempted a reconstruction of what actually happened using Rous-Marten's original data.

 

He concludes by saying "Although we shall never know precisely what happened, my own conviction is that with one exception of the time at Wellington station, Rous-Marten's published figures were accurate. I feel that a maximum of at least 100mph may be accepted on City of Truro's behalf."

[John_Hughes]

 

(snipped)

 

That said, there are several locos with prior claims of 100mph running, including this one in the Chicago Science Museum:

 

http://i1268.photobu...5_6585204_n.jpg

 

(apologies for camera shake).

 

Yes, and that particular one one really is a poor joke since the record claim was based entirely on station operators' telegraph signals and the time the train was logged 'OS' (On Sheet in the Train Register).

[LMS2968]

Surely the only way that kettles can do 100 plus is vertically downwards..............

 

Speed is a function of Power and Force Applied (Power = Force x Velocity) applied to the weight of the train, so the higher the power, the higher the speed. Since some steam engines have exceeded 3,000hp, 6229 Duchess of Hamilton exerting a calculated power output over 3,600hp - more than a Deltic, it's difficult to see why that would be so.

[Gwiwer]

Many of the salient points arising from the original topic have been covered. Distilled to a summary we shall never be able to verify beyond reasonable doubt the veracity of the claimed maximum speed for CoT on that run.

 

The historic and in some circles contentious claim of the top speed has been examined minutely over the years by the World's greatest and most proficient recorders of locomotive performance. We can apply modern technology to older records and suggest that perhaps the claimed maximum was not achievable in the circumstances (load, weather, known previous runs with the same driver / fireman for example) but what we have is simply one log compiled by one recorder with one stopwatch probably with 0.1 second accuracy.

 

That would have been perfectly adequate back in the day and considered the best recording available. Locomotives were not fitted with speedometers and the digital age was not even dreamt of. There are all manner of possible variables in terms of milepost sighting (and indeed siting since far from all are / were at precisely the correct location - albeit wide variations were generally well documented) and consistency of observation. What worked perfectly well at more typical speeds of the day (perhaps 60 - 75mph) might not have proved so reliable at 100mph. The merest fraction of a second adrift in clicking the stopwatch could give a variance between 91 and 108mph with a 0.1 second piece. The rise and fall of speed must be compared over consecutive (not alternate) quarter miles to achieve reasonable consistency requiring either two stopwatches or a rather up-market one which was seldom seen in those days as I understand it with two "stop" hands under independent control - such devices were more widely available much later and indeed I used one myself in a brief flirtation with train timing.

 

Today we have computer-derived data for acceleration, braking and power output for any modern class you can think of. Back in CoT's day there was little more than the theoretical EDBHP (equivalent draw bar horse power) figure which meant more to the engineer than the driver. What we can now analyse however is the likely rate of acceleration given the known load and weather records showing wind speed and direction plus likely railhead conditions. These were not entirely in CoT's favour.

 

Recent examinations of the claimed record including one in Railway Magazine a few years ago have suggested that all things considered the maximum would have been not more than 99mph but given the margin of error which was inherent in the recording method then any speed between 96 - 102 mph would have been theoretically possible but is not verifiable by any means.

 

As such the claimed record is regarded as non-authenticated but not non-authentic. It is certainly possible that CoT attained the claimed speed or at least exceeded 100mph as a brief maximum - possibly even over successive quarter-miles. The one consistent theme emerging over many years and many re-examinations of the matter is that we shall never know for certain. But we also should not deny the Old Lady her place in history based on suspicion, doubt or the fact that 100 years on there are extremely precise recording methods unheard of back in the day.

 

As a postscript may I add that I also once had a high maximum speed cast into doubt. I recorded the 03.20 Victoria - Brighton passenger + News one night towards the end of its days (as the short-lived hourly all-night EMU service had just been introduced) with a 73/1 and around seven Mk1-type coaches and vans. A lively performance throughout was capped by what I recorded as 102mph at Tinsley Green based on nocturnal milepost observations and which appeared consistent with a 98mph through Gatwick Airport station and a sharp braking to 85mph for Three Bridges. All of those speeds were and are above the permitted maxima. The 102mph was queried by a recorder far more experienced than I who showed by means of a power : weight graph that the 73s simply didn't have the known capacity to accelerate the given weight by even those 4mph over that short distance. I accepted the point and that the likely maximum was nearer the level "ton", and that I may have been a little hasty clicking the watch or possibly mis-sighted another lineside feature for the milepost.

[The Stationmaster]

It's interesting to compare the comments in this topic about stopwatch timing with what BR considered adequate for train timing and disciplinary purposes until radar guns and stop watch timing of track circuit occupancy came along - a stopwatch graduated not in just in seconds but in mph, and it was used for checking speedo readings. And note I included 'disciplinary purposes' (and that was very much the case with stop watch timing of track circuit occupancy which could very definitely lead to Drivers being disciplined or taken off for exceeding speed limits). It's also interesting to see how consistent experienced observers can be when comparing times taken on the same train however I would never deny that there is always going to be a margin for error with stopwatch timing (just as there is with loco etc speedometers).

[pointstaken]

Does anyone really care ?

 

Dennis

[beast66606]

Does anyone really care ?

 

Dennis

 

Those who contribute usefully to the topic perhaps

[Oscale]

Although unofficial, reports that the New York Central RR's loco number 999 reached 112.5 mph on 10th May 1893 would invalidate the Great Western's claim to be the first in the world to run a train over 100 mph anyway.

[roythebus]

They're actually two completely different beliefs.... Contrary to what the media would probably tell you, throughout most of the Christian era it has been generally accepted that the earth is round - this didn't start with Gallileo & Columbus.

 

However, you do make a valid point in that ultimately nobody can conclusively prove anything that happened in the past without making certain assumptions that may or may not be shown to be incorrect at some future date, whether that be assuming that Rous-Marten's timings were accurate, or assuming that rocks are always formed with the same ratios of certain radioctive isotopes.

Sorry, beliefs.

 

Also cast your minds back to early railway history when it was believed that people would suffer travelling at speeds of 30 miles per hour; horses would bolt and the earth will come to an end.

 

Meanwhile, I'm happy to believe that CoT exceeded 100mph on that day because there's nothing to prove without reasonable doubt the contrary. Similarly, I'm happy to accept that my fast Deltic run in 1978 was 114mph, not the 120-odd I seemed to remember it was because someone has proved my memory wrong.

[MarkC]

What I don't think can be in dispute is that it must have been by degrees exhilarating, terrifying and above all so satisfying to have been on the footplate that day.

 

Quite so

[Andy Kirkham]

And then there was the surprisingly little-discussed exploit of 2903 Lady of Lyons in May 1906, running light between Swindon and Stoke Gifford.

 

Among those on the footplate was C.B.Collett who later affirmed that a speed in the region of 120 mph was attained. Indeed the speed calculated from the times recorded by the signalmen at Little Somerford and Hullavington was 135 mph!

 

(see Tuplin - Great Western Saints and Sinners)

[roythebus]

Muckfee, how on earth did they stop it from that sort of speed?