Cathedral Express 23rd May

I have to admit I always take speed records with a pinch of salt. This is not to doubt the accuracy of the speed but just that unlike other speed records there seems no universal criteria and the UK ones at least very much appear to rely on the run being down hill. Hypothetically any body with enough money and a loco could break the speed record if they being could build a straight enough track on a steep enough hill!

In terms of speed I would like the record to be earned by a loco that ran the fastest pulling a minimum set load on a flat track, possibly averaged over a set length rather than a loco peaking for a second running downhill. Thus any speed was down to the loco rather than anything else. I appreciate that this can not really happen due to the nature of railways and you can not really build a test bed at Salt Lake. It still maybe the A4 in the UK but I would like an idea of what was basically the fastest loco on the flat and what sort of speed it could be reasonably expected to achieve and maintain.

 

I assume you are referring to the Southbound run as there was no conductor on the Northbound.

 

Indeed.

PS: Also on 23rd May 1959 60007, after achieving achiving 112mph down stoke, again reached the full 100mph but on level track just beyond Tempsford. I'm not sure how many other times an authenticated UK 100mph has been attained (i.e. not just maintained) on level track - but I bet its not many! Some on York - Darlington maybe.

 

No idea about blast tip area.

But the loco was originally built, (as a tank loco!), to operate a high speed Berlin - Dresden service. But WW11 stopped that.

And was rebuilt to test high speed coaches in the eastern block! Running up to 180 km/h on a several occasions, plus that one 190 km/h run whose details I still cannot locate.

So I think a steam loco that has demonstrated a 112 - 118 mph capability was probably equipped with 7 foot six inch driving wheels for a reason!

Plus a good blast tip area no doubt!

PS. How often has a 5 foot 10 inch driving wheel loco, (with a good blast tip area of course), got up to 118 mph? Only asking. But in my research into high speed steam loco running I have seen some real rubbish claims!

 

110mph with two cylinders, dial in the improved balancing of a 3 cylinder design and who knows what would be possible. The Americans were far better at designing the mechanical side of locomotives than their British contemporaries. 18 201 is first generation steam and so is very limited, interesting, but limited none the less. Driving wheel diameter should be no larger than it needs to be, after all a 75mph design can be produced around driving wheels of 4' 2" in diameter. So why was 18 201 fitted with 7' 6" drivers? The designers didn't know better, this was part of the state of play at the time but only for some.

 

I guess you are right re the design history of 18 201. But it has proved itself to be a very fast steam locomotive. So whatever the shortfalls in design, the basic technology does work!

Re the USA. Some outstanding steam locomotives. But also one enormous problem. A real shortage of proper data from virtually all of the so called fast runs. "Should be taken with a pinch of salt", used above most certainly applies to almost any USA report of high speed steam runs.

I've come across this time and time again in my search for the first steam loco to reach 100 mph, (highly likely in the USA), and also the fastest steam loco ever, (a possibility in the USA). Mileposts were notoriously inaccurate and serious timing was not a USA hobby. Some of the claims made are simply ludicrous. Some based on average speeds calculated from times written down, (mainly to the nearest minute), at passing locations by staff stationed there!

So I've had to chase the work done by serious European timers who went to the USA, (such as Baron Gerard Vuillet), and research done by such as John Clay and Brian Reed.

I've not checked to see if the Forum has a thread on the two subjects I mentioned above, (first steam loco to 100 mph and fastest ever steam loco). If not I may start one, to avoid cluttering up other threads with off topic information.

 

The very nature of the steam locomotive, imperfect it all too often is, but it works and sometimes it works well, very well. I must agree with you that obtaining accurate, reliable performance data can prove to be difficult if not nigh on impossible. For the N & W it appears that the company were truly interested in what their engines could actually achieve. They were "their" engines too in the main, they designed and built their best designs in house. It also appears that they did not shout too loudly, not many people know that the class A articulated produced just as much power as the larger and later UP "Big Boy". Then you look further at the shed facilities that supported these designs, this country had nothing that compared. If you cannot maintain a machine easily it tends not to be maintained at all.

A large number of designs witha high speed potential never realised their full potential. Gresley was sure the A4s could achieve 130+mph, the Chapelon compound pacifics ran at 110mph while engaged in pantograph testing but were never extended, maybe E41 will be restored and make it to Poland. The future holds the chance for fresh records, we live in hope.

 

I' have now opened a thread under STEAM TRACTION for those who want to continue this interesting subject.

Well. It is interesting to some of us!

http://railways.national-preservation.com/viewtopic.php?f=28&t=19834&p=295726#p295726