Tornado hits 100mph

[S.A.C. Martin]

Reported all over the news today. Tornado hit 100mph on a test run last night. Just brilliant. Opens the doors for 90mph running behind her. Well done to the ladies and gents of the A1 Trust and Network Rail. Phenomenal achievement.

[richard]

Yes the press release was waiting in my mailbox this morning. Looks like the test results need to be analysed and certification processes to complete, but they hope this will be done before the end of 2017.

[Hatfield Shed]

So long as they have a supply of firemen with the neessary stamina. A power stoker would be a sensible item to put on the P2 while it is building.

[Nova]

Wow! my first thought when I heard the news was "Holy ****"

what a triumph for steam in the 21st century and showcasing the credibility of the original Peppercorn design! no doubt other 8P locos such as the A4s and Duchesses will be able to keep up though I can't help but wonder if smaller or less powerful locos like the FS, the two Royal Scots, Jubilees, etc. especially the P2 with it's smaller driving wheels will be able to attain such a speed and hold it. might be worth the P2 SLT investing in an electrical firing system like on those swiss locos during WW2

[richard]

Hatfield Shed: My understanding is that when the tender was made it was modified from the original design so that an oil tank could be easily fitted if need be. I assume this is still possible.

[Trestrol]

There will be a documentary about the run on BBC1 next month apparently.

[Mickey]

Don't know to much about the technical aspects of steam locos but whenever anyone on here makes a comment about running preserved steam locos above the 50mph speed limit someone else points out about the wear & tear on the locomotive and the higher costs in money & maintenance involved at running at higher speeds!!. So maybe higher speed running isn't a issue anymore?.

Mickey

[Hatfield Shed]

The Pepp A2, Bulleid and Riddles pacifics were all built with the same nominal 74" wheel diameter as the P2, and would all manage a sustained 90mph.

Maintaining high speed requires sustained power delivery, and that capability is directly proportional to grate area, all other factors being equal. Narrow firebox types effectively hit the limit of what is practical within the UK loading gauge in the 1930s.

There's calculation required for the trade off between higher speed and greater maintenance spend consequent on more wear. If there's extra net income resulting from operating at higher speeds, sufficient to meet or exceed the increased maintenance spend then all is well.

Hatfield Shed: My understanding is that when the tender was made it was modified from the original design so that an oil tank could be easily fitted if need be. I assume this is still possible.

I believe it is. But it don't smell like burning coal, nor do any nice fireworks result at night. Modern turbine tech would likely deliver yet more power for any given steam supply too, but then it wouldn't chuff. Determinedly atavistic original steam experience man here, cinders, smoke and all. I want to hear once again the deep whum, whum, whum fundamental bass note of a fast approaching three cylinder loco with steam on: that was the marker of a train that was really moving on the ECML...

[JASd17]

I do not believe the A1 was necessarily designed to run at such speeds. Clearly it can.

The post-war track and many other considerations made hauling long trains at relatively high speed, say 60 to 70 mph for a 600 ton train more of a design priority.

As far as I recall there was no return to the 1935-9 streamliner times, for steam locos.

And may I add, the average East Coast and GN Area Express, even in the late 1930s, did not require very high speed.

John

[manna]

G'day Gents

Not a lot heard about it over here, but Congratulations to Tornado anyway. Could some of this high speed running, be down to pathing, especially on the ECML !!!!!!!!!

manna

[Mickey]

These days the actual condition of the p.way right across Network Rail has probably never been better and of a higher standard and probably well suited for high-speed running with long welded rails and deep ballasting being the order of the day and even on secondary lines the standard of the p.way is much better than it use to be as well so there's probably never been a better time for high-speed running.

Compared to days of old of running fast down Stoke bank on short lengths of jointed rails with ordinary ballasting with the loco cab swaying about!!.

Mickey

[greenglade]

It's great to see this but I doubt if it will become a regular thing...yes the P.W today may be far better than days of steam but part of that will be due to the fact there is no steam. Add steam expresses going at 90+ and the resulting hammerblow (something today's P.W doesn't have to deal with) the P.W will soon need more maintenance to keep things ship shape.
It would be nice to see regular ton up steam expresses but I doubt that it will happen...

Pete

[richard]

I assumed the instrumentation that is talked about looked at things like estimating hammer blow (not sure how they'd measure it, but I'm sure Network Rail would be very interested before signing off on such runs).

[Hatfield Shed]

There are techniques using load cells under the rails to assess dynamic loading if required. With standard traction in the regular traffic moving yet faster, and thereby causing greater rate of change in loading, I doubt the occasional steam loco is much of a problem to the current rail and track standards.

There is however another problem inherent to the reciprocating direct drive steam loco. The drive cannot be completely dynamically balanced, and the use of wheel weights to partially balance reciprocating masses are a particular difficulty. It was observed in the 30s that steam locos pressed to speeds in the 120mph range were capable of lifting tyres sufficiently clear of the rail that the flange would no longer be effective. The machine essentially 'gallops'. The flange is not actually working on normally aligned track for high speed, but it is the safety check should something go awry...

One solution is not to balance for reciprocating mass at all, only the rotating cranks, which can be done adequately. Too late in the day for this technique to come to maturity, but it is suggested that this balancing resulted in a propensity to slipping at high speed. The unbalanced reciprocating forces are absorbed on the locomotive frame. This was probably not going to trouble the cast steel frames latterly used on North American locomotives, especially given their relatively short service life expectation. Quite how it would work out on plate frame construction is another question without a definite answer.

[Trestrol]

Tornado TV programme Monday 15th May 19:30 BBC1. Nort East/Cumbria/Yorkshire/Lincs only. Probably get it on iplayer.