Line Speeds

[CVR1865]

Hi Forumites,
Having read through the threads running here abouts relting to the Talisman and Elizabethan, they touched briefly on the difference in power delivery characteristics of steam versus diesel. Now my persona experience of the footplate is limited to milling around one does on preserved lines at 25mph so it is not a fair measure of the power delivery system of even a small tank engine, all stop starting and running round.

Anyway back to my point of starting a new thread, how does/ did a driver ensure that he kept to time and up to the line speed? I remember from reading about Mallard's record attempt that the LNER had a maximum line speed of 90mph at points on the ECML, was this a realistic cruising speed?

I imagine, and wonder if someone can confirm, that a good crew, as all the top link men surely were, would be able to balance the demands of the terrain and the needed line speed against keeping the fuel on and water topped up, through judicious use of the regulator. I have always been assured that blowing off is only a waste of steam so it works both ways.

A curseory look at the timings for top trains it would seem the Flying Scotsman under A1 power was timed to an average speed of 49mph with it later increasing to 60mph under A3/A4 power. This seems pretty fair with the need to slow to cruise through stations, reversing curves etc and then re-accelerating.

I realise this is just the cruising speed of the very top expresses and that the everyday would have been much slower barely getting above 30/40 for most stopping trains plodding around, however my curiosity was sparked by talk of the namers.

Thanks for any info or light that can be shed upon this.
Simon

[Blink Bonny]

Ay up!

Basically its all about the point-to-point times. From these the average speed would be worked out in the office and woe betide the driver if he was late for no good reason.

He could make up time in two ways: a higher maximum speed where possible or by accelerating faster. This is where the steam loco won out ovewr diesels. The timing office staff would have acceleration curves for the various types and loads produced following on the road tests and a lot of work with slide rules and they would know that to accelerate from the Peterborough slack (25mph) to line speed northbound (90mph) would take say 10 minutes at "average" working rates. By dropping the cut-off out by another 5-10%, more power is released from the cylinders and so acceleration is accerlerated. With diesels full power is just that and no faster acceleration is possible once full power is achieved plus with electric transmission, the amperage being fed to the traction motors has to be regulated or there is a flash and a bang from underneath and the whole thing comes grinding to a halt!

Out on the line, line speed, rolling stock speed restrictions and loco speed restrictions are the order of the day. While there was no official upper limit on most classes, drivers were expected to exercise due caution. Although 90mph is possible with a 9F and the engines were, apparently, willing to do so this is not good for the engine. High piston speeds lead to accelerated cylinder wear and excessive forces building up in the valve gear. Remember that both the LNER A4 speed record attempts led to serious damage to the engines concerned possibly due to engine overspeed. However, 100mph was within the capacity of any engine with 6' 9" drivers, all other things being equal, and for the sort of turn where this sort of speed was required would have been hand picked in any case unless there had been a failure.

The Streamliners pre war were timed to run at 90mph wherever the line configuration permitted it abd certainly "cruised" at that pace for mile after mile. Post War, things were slowed down a bit with the exception of the "Elizabethan" which ran at more or less Streamliner speeds but with a heavier load.

[2512silverfox]

Legend has it that Bill Hoole did not carry a watch and used to check the times from signal boxes en route. He then ran as fast as he could on the basis that could not then be late!

I had a girl friend once whose father was the guard on several of Hoole hauled expresses, and he told some stories about speed and being ahead of time!

[Blink Bonny]

Ay up!

There's a lovely story regarding Driver McCann of Stranraer shed. On a late running train, he'd been driving particularly fast to make up time. The Guard stomped up the the cab and said "Look, mon, I don't mind you makking up time, but can ye go roond the bends an' no' cut across 'em."

Driver McCann's response was not recorded.

[harvester]

Before the coming of the diesels and canned power I always thought the times would have been arrived at by passed experience of workings over the various sections with trains of known weight and the class of loco allocated, plus allowances for other traffic. I also imagine the drivers would have worked over the line many times before being in charge. as passed cleaners firemen ect. and would have a good feeling how hard to work the engine to keep the point to point timings. I also remember reading about Bill Hoole "run hard and the bobby will slow you down if you get too far infront"

[bricam5]

Apart from stabling and prepare link, every driver/past fireman had to learn various routes and to sign the route book when that route was thoroughly learned.
Timing could be done by signals or signal boxes sometimes by landmarks.
An experienced driver would know to within a quarter of a mile where he was at any given time and at what time he should be passing the salient points he had learned.
It was always good policy to push a wee bit faster on a stopping train as the guard would hold it in the station until departure time.

By the same token, an experienced fireman would be almost as well aware of the route and of his drivers technique i.e. when he shut off at junctions or dropped a couple of notches on the valve gear for inclines etc.
As an instance, going flat out from Hull towards Doncaster I would let the water drop below half a glass knowing that my driver would shut off for the facing points at Staddlethorpe junction. Blower on to clear smoke then both injectors on. When the regulator was opened again we would have a full glass and a full head of steam.

Team work, engine knowledge and route knowledge and knowing what you were pulling.

[Blink Bonny]

Ay up!

A chap, now sadly passed away well before his time, told me that there was a three man team. Driver, fireman and engine.

Trevor Owen of Lostock Hall - RIP

[StevieG]

Possibly of a little background interest Simon (OP-er), I'm not sure about the predecessor equivalent LNER 1947-issued books, but in the BR-issued Sectional Appendices for the whole country of (in a few cases, around 1958-)1960, the Table A pages, with locations listed vertically and the number and type of tracks shown alongside, showed a maximum permitted speed for (usually long-ish) sections of line (I think, hence the oft-mentioned term "linespeed") as a heading, and then listed the lower-speed local exceptions in appropriate places down the table, with mileages or some other words of description as to where and how they applied.

[manna]

G'Day Gents

I can give you an insight into a diesel working at the Cross one night, I was working on a Moorgate - Hertford train when the driver said to me , I'm going to see how far we can get ahead of time, well I soon found out, we came into every station, hard, the brakes were slammed on and we came to a screeching halt at the end of the platform, and that was only 'Barbican' and again at Farringdon St, didn't work so well at KX, but still ahead of time, we left KX a little early, after that it was the same at every station, hit the end of the platform and drop the brake, the guard didn't bother about right time as there was another train only a couple of minutes behind us, well we made it to Hertford North 10 minutes early but boy was it a rough ride, and not one complaint !!!

manna

[Mickey]

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[Bryan]

Broken rails and damaged sleepers being the main results.
And for the neighbours a disturbed nights sleep.

[Mickey]

Deleted

[manna]

G'Day Gents

Only time I've seen a driver drive that way, all of the others would slow down before the station and stop in the platform on a rising brake, the best were the engines fitted with a straight vacuum brake, ( and there were still quite a few about).

manna

[Blink Bonny]

Ay up!

I've seen Evening Star plus 5 stopped on the Worth Valley on a rising gradient using just the graduable steam brake valve.

[Mickey]

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