LSWR H16 tanks

Would this require more trains to be run than currently to accommodate the passengers carried or would it be possible to get the same capacity but in a lighter train?

 

The train I referred to earlier on has capacity for for between 200 and 250 people and has provision for wheelchair users and a rather disproportionate amount of 1st class accommodation as well. More third class would increase capacity. Two of the vehicles are saloons which reduces capacity in rather the same way as corridors and lavatories do in the heavy stuff. Certainly no weighty buffet vehicles. Coal consumption for an A1x, so I have been told, is around 1 ton per day. Whether such a capacity is adequate in all circumstances I could not say but all I am really saying is these issues require thought which IMHO they have not always received.

PH

 

A bit of thread resurrection / drift:

It was asserted earlier that Craven's engines were all scrapped very quickly after Stroudley took over, whereas those of other designers had much greater longevity. Wondering if this were true, I thought it would be interesting to make a comparison between Craven and some of his contemporaries, specifically:

James Cudworth, CME of the SER from 1845 to 1875
John Chester Craven, CME of the LBSCR between 1847 and 1870
James Hamilton Beattie, CME of the LSWR between 1850 and 1875.

The graph (below) shows the number of engines by each designer in traffic each year, that is the difference between the cumulative number built and the cumulative number withdrawn. It basically considers new builds and ignores any rebuilding, though in the early period that is a slightly grey area. It also ignores the distinction between locos built at the home works and built by external suppliers, simply looking at the total locomotive provision on the line in question.

Locos to the design of the specific person but completed after their departure are included, specifically a few Craven locos completed by Stroudley, and some JH Beattie locos completed under his son WG Beattie. However the Ramsbottom 2-4-0s built for the SER and delivered in 1876 are not included: it was the ordering of those locos by the Board behind Cudworth's back that precipitated his resignation.

Looking at longevity, a few things are apparent.

Firstly, the last locos to be withdrawn were 1905 (Cudworth); 1899 (Craven) and 1962 (Beattie). The relative longevity of some Cudworth locos is entirely down to two classes: the standard 0-6-0 goods and the standard 2-4-0 passenger engine, both classes built in large numbers. The longevity of Beattie's engines into the twentieth century is down to a group of outside-frame Beyer-Peacock Goods locos that survived to the formation of the Southern Railway; and of course the three famous well tanks.

Probably a better way to look at longevity is to see how long it took after the departure of the designer for their locomotive stock to be reduced to only, say, 10% remaining. The comparative figures are:

Craven: 203 locos; 90% had gone at some point in 1894, which is 24 years after his departure
Cudworth: 316 locos, 90% had gone by the end of 1901, which is 26 years after his departure
Beattie: 330 locos, 90% had gone by the middle of 1898, which is 23 years after his departure.

On those figures it is clearly wrong that there was a mass clear out of Craven locos by Stroudley: they lasted about as long as those of his contemporaries relative to his period of office. I haven't got the average ages, but I suspect there would be little to choose between Craven, Cudworth and Beattie, especially if the three obvious outliers are removed. In particular, I think if you just considered the locos of JH Beattie built up to 1870 (the year Craven resigned), the shape of the graph for LSWR and LBSCR would be very similar: Beattie of course had five years more engine building, so his designs lasted, broadly, another five years beyond Craven's.

I don't suppose anyone else will be interested, but I found the analysis interesting!



Tom

 

Easier perhaps to understand as a line chart, but yes, its very interesting. I think its very difficult to understand loco policy without doing that sort of exercise, and also of looking at what replaced what. Looks to me as if the Craven curve is distinctly skewed about 1863-1869, suggesting a sudden outbreak of loco building. An alternate presentation would be to line up the charts with the retirement dates together. If a glance serves me right, there's a suggestion that the main body of Beattie locomotives were if anything withdrawn a little faster than his colleagues products, but again that might be because he was active longer.

The fly in the ointment with the 19thC loco populations is renewals. I've done a medium sized study of the GW locos, and there are no hard and fast lines between new designs, significant rebuilds or simply repairs. Its often quite difficult to decide what was a separate class. In the case of the GW, which seems to have had a marked aversion to building 0-4-0T, their small number of absorbed 4 coupled tanks went through all sorts of manipulations, with one-good-from-two rebuilds, major changes, minor changes, custom boilers and goodness knows what, in some cases right up to the 1930s and even 1940s.

 

Tom, has the Bluebell ever hired in one of the well tanks, and was it any use? Your idea of a 50 ton 12,000lb 2-4-0 loco is roughly one of those with a tender; more powerful than a P or Terrier. For comparison a GWR 14xx is 13,900, so of a similar mignitude to one of those, and well up to 6 or 7 4-wheelers.

 

Here it is as a line graph, just for you. I've got an idea for re-plotting to show the relative rate locos were scrapped, but it will have to wait until after the children are in bed!

Totally agree with you re rebuilds, reboilering, renewals etc - a complete minefield!



Tom

 

I can't remember ever having a Well Tank. (Interesting incidentally that some of the Beattie Well Tanks spent a portion of their lives rebuilt as 2-4-0 tender engines!)

It's all a bit hypothetical at the moment, as you also have to balance carriage provision: at the moment we only have 3 four wheelers (or the Mets) though in probably 3-ish years that number might be 6; but I suspect it will remain 6 for a period after that while attention focuses on Maunsells and Bulleids. So really the ideal question would be "what do we need to haul 6 four wheelers on our gradients, but with capacity to pull a bit more in the long term?" Which is partly why I think we need something bigger than a P or Terrier, but not as big as the H, O1, C or E4. An ideal loco, and appropriate for the line, would be a Stroudley E Tank (cough cough) or, more realistically, a D tank which is basically a passenger variant of the E tank.

Tom

 

Ok, here's the graph that shows the relative rate that each designer's locos were scrapped. It is normalised to their total stock (i.e. expressed as a percentage, not in absolute terms) and the scale of the x axis is relative to the year that the designer left office, so year 0 is 1875 for Cudworth and Beattie, and 1870 for Craven.

It is striking that - give or take the fluctuations caused by individual years that would clearly be related to detailed policy and the financial health of each company, that Craven's locos were scrapped no quicker than Beattie's.

Interestingly, Cudworth had scrapped 20% of his own fleet while still in office! Which I guess is explained by his early start building locos: his first engines, constructed in the late 1840s, can't have continued in their intended role for much more than 10 years or so, and were mostly gone within 20, still within his time in office. From about 1860, the pace of development slowed, and locos started to have longer lives.



Tom

 

Nice work. I think we can acquit Craven of the charge of designing locos that were scrapped earlier than those of his peers.

 

Indeed. I think the charge of designing too many locos has to be set in context as well. It's true that the chronically poor repair performance of Brighton works led to Craven's dismissal. Part of that was due to the non-standardisation of locos, though the poor and constrained nature of the site can't have helped.

But the flip side of lots of standardisation is it can limit innovation and development. Cudworth lost his job because he was too wedded to his standard designs. As the traffic developed in the 1870s he ran out of options for incremental development (cylinder size, boiler pressure etc) of the standards, but wouldn't design anything bigger. The final straw was a chaotic traffic situation in the summer of 1874, which prompted the board to review the situation and then order some locos to the design of Ramsbottom, essentially similar to the LNWR Precedents.

So it's a double edged sword: too little standardisation and the board force your retirement. Too much standardisation and the board force your retirement! I can't help thinking that all their CME's were on a hiding to nothing due to the layout of Brighton works: had the board grasped the nettle and moved to a green-field site (as the LSWR did) then maybe Brighton locomotive affairs may not have been so chaotic.

Tom

 

Fascinating! And all this from a mess-room suggestion to combine bits of S15s left-over at Ropley and Grosmont to make an H16 tank loco! (thank you Martin for the idea...)

 

It is very interesting. However, Tom, I'm not sure I fully understand the x-axis of your most recent graph? Especially the negative numbers.

 

0 is the year the CME/Superintendent retired/resigned, so negative numbers are while he was still in office. So Cudworth's long career and the short life of may of his earlier designs is why the negative range is so much longer in his case.

 

It shows how quickly each specific designer's locos were withdrawn after they left office. The very similar slope of the line for both Beattie and Craven shows that the assertion that Craven's locos were withdrawn very quickly by his successor is not borne out by the facts: his locos were withdrawn no quicker than those of his contemporaries.

The negative part of the graph shows locos withdrawn while the designer was still in office. For Cudworth in particular who had a long tenure and started building locos very early, he had already withdrawn a sizeable number of his own locos while still in office, mainly locos built in the late 1840s and early 1850s that were no longer fit for purpose well before his resignation in 1875.

Tom

 

Understood. May I enquire as to your source for this information?

 

It's my aggregation and presentation from the data on individual build and withdrawal dates in the appropriate volumes of DL Bradley /RCTS histories of SER, LBSCR and LSWR locomotive history.

Tom