Brighton Atlantic: 32424 Beachy Head

Just to correct that - I don't think it is remotely practicable to have "weather forecast specific" motive power decisions, even if sufficient spare locomotives existed to give a choice. Locomotives tend to work in blocks, which helps overall efficiency and reliability by keeping them warm for an extended period. After a period in service, a loco will come out for a washout (and any other attention needed) and be replaced by another loco of suitable size for the duties required.

Very occasionally, operational issues may require a loco to be steamed at short notice, but it is avoided where at all possible. We certainly wouldn't wish to steam a loco just because someone looked out of bed one morning and saw it was raining (even if as crew we might prefer a last minute switch from O1 to H!)

What that means for loadings is that each loco is given a load limit that is based on being able to haul the required loads in all conditions - those limits are necessarily lower than what could be achieved in optimum conditions, because they assume what can be safely hauled in poor rail condition, boiler nearing washout etc. The ability to restart a train on a 1 in 55 gradient is one of the limiting factors.

The limit for Beachy Head still needs to be incorporated in our rules, which I imagine will take place with a period of testing before being handed over to traffic. In practical terms, our normal regular train weights are up to about 220 tons which is limited by platform length: most locos of class 5 and above have a load limit in excess of that and therefore platform lengths tend to be the limiting factor on the trains worked. Locos smaller than a class 4 tend to have correspondingly lower weight limits and the locos themselves effectively become the limiting factor on train weight.

Tom

 

I must be out of my mind then as if I get any real slipping the first thing I'll do is slam the reg shut. After the slip has stopped, if not in full gear I'll probably wind it that way and open the reg carefully. I'm certainly not going to start fighting with a reverser on an LNER loco that will probably be wrenched out of my hands the moment I take the catch out If it is only a slight slip I might pull it up a bit but only a slight slip.

 

60532 Blue Peter, Durham, October 1994.

 

In fairness it's not quite a direct comparison - 60532 unique amongst preserved LNER express steam in having a multi-valve regulator. I don't know the exact ins and outs but I do know it's not the standard double seated Gresley affair (perhaps Steve could enlighten us - I think you have driven 60532 before?)

 

while I understand your points , in these times of 10 day LR forecasts it definitely is possible to make forecast based decisions . it would also be of use in deciding what class of loco to use .
if the weather suggests a class 3/4 will do the job with regard to expected passenger numbers ,keeping a fire in a BB does not make financial sense

I use them to plan my offshore angling trips , and supermarkets find them an invaluable tool in predicting what stock to order.

 

Yes, but having sufficient surplus locos available to give that level of choice - which by definition will end up under-utilised for much of the time - works out more expensive than sometimes running a loco that is a bit too big. Maintenance is far more expensive than coal, so the route to efficiency is high utilisation.

Besides, suppose you have two days of “class 2” traffic weather in amongst a week of “class 5” weather - better and cheaper to keep the class 5 in steam throughout than let it cool down then have to heat it up again two days later.

Tom

 

Yeah but, lets take the example of the Bear, because I have the numbers. The centre of gravity is approximately 15 feet in front of the radial axle, and there's 96 tons pressing down through that COG. She had a tractive effort of about 14 tons, coming through a drawbar about 3ft 6 off the ground. So the 96 tons is pushing down with a 5:1 mechanical advantage over the drawbar pull, and in any case the greatest weight transfer is surely off the leading bogie. I'll believe a real engineer if they show me the maths, but in the absence of the sums I cannot visualise a significant change in the adhesive weight on the driving wheels.

 

As I understand it, the driver was injured when, once he realised that he couldn't close the regulator, due to what we now know was massive priming, he tried to wind her back to mid-gear in an attempt to stop the slip. Once he took the lock off, he lost control of the reverser as it flew round.

 

I have driven 60532 on several occasions (as my avatar shows) and there is, indeed, a difference between the multiple valve regulator and an LNER double beat regulator. The multiple valve reg is more controllable but it seems to me that it gets harder to open the further you open it for reasons that I can't explain as I wouldn't expect that characteristic. I got the same impression when driving 71000, which also has a multi-valve reg. I don't think i ever had to control a significant slip when driving 60532. I have had fun and games with 71000 in trying to re-start it on the 1 in 49 at Darnholme (actually 1 in 42 at that point.)

As I understand it from the NELPG rep on the footplate at the time, the driver did not have the reverser lock in when the slip occurred. (He had already been reminded of this on more than one occasion.) The reverser handle started to fly around and hit the drivers arm. There was no attempt by him to shut the regulator and it was eventually shut by the NELPG rep but by that time the damage had been done. Now LNER pacifics have two reg handles, one on each side of the footplate but it had been deemed a good idea to remove the fireman's side one on safety grounds.
My earlier comment on LNER reversers referred to the fact that they generally had coarser lead screws than LMS & BR locos and, if not locked or firmly held, the reverser handle could easily start to spin back and forth if a slip occurs. That is certainly the case with the pacifics, B1, K1 & K4.

 

Good grief - that's even worse then, Steve. Wow.

 

I am in 100% agreement with you Steve. If the loco gets into a proper slip you immediately close the regulator. If you start fannying around with the reverser you run the risk of the slip becoming uncontrollable, with the consequent chance of damage occurring. If you feel a slight slip, then you can by all means shorten the cut off to mitigate it and, once the slipping has stopped, maybe put the sanders on for a spell.

 

But you wouldn't have class five vs class two weather, you would have more grippy vs less grippy loco weather, which raises the question of whether any loco is so prone to slipping that you wouldn't use them at all...and I would answer not. You might make sure the sands are full, but otherwise adapt your driving technique around the conditions. To give you an example Calbourne can slide when running round at Smallbrook if the rails are greasy, so go a bit slower

 

From personal experience, so can* the 38 stock when departing Smallbrook too enthusiastically from t'other side of the platform.

*that possibly ought to read 'could' by now .... it's been a while.

 

I'd be interested to see a comparison in fuel economy between a Bulleid with six on and something like a 4MT or even one of the smaller pre-nationalisation types (e.g. C-class, Q-class)... I remember Top Gear lapping a Prius flat out round the track with a BMW M3 loping along behind it, burning less fuel! Given Bulleids' legendary capability for producing steam, is it possible to get them to do the job on a thin hot fire, or make a thicker one last longer?

 

Part of ELRs rationale for purchasing 34092 is that it apparently uses no more coal than a 4MTT on like for like duties, albeit more to bring round from cold.
I've heard similar said of other wide box locos as they are extended less and it only takes as much to keep the grate covered thinly, producing enough heat, as a wedge fire on a narrow box.

 

This may be true but beware of big chufferitis.

PH

 

Another update:

http://www.bluebell-railway.co.uk/bluebell/locos/atlantic/latest.html

Firstly, some lovely sheet metal work making parts for the boiler cladding. These were done by an external contractor as training for their apprentices - I had a quick look this lunchtime (before an afternoon of firing) and they are beautiful to behold.

Followed by some more work preparing the boiler for a later hydraulic test.

Tom

 

As it goes, much as I admire both ELR and 34092, in the case of their proposed marriage I tend to agree with the phrase applies.

 

Al, its easy done, meadsted bank can be difficult in both directions in the damp conditions, I can remember Dave Fewin getting stuck on the first out of Alresford on 506, an engine that very seldom slipped, I was his fireman that day, and we was virtually down to walking pace but managed to keep going,