The Bristol Railway Archive

On another thread Roy wrote:

the green mile wrote: Sat Apr 24, 2021 8:31 am I appreciate we have wandered completely off at a tangent here but let's take this discussion a step further.

When a loco disappeared off to Swindon Works for overhaul, I'm wondering if a replacement loco was slotted in to make up the allocation. And when the original loco was released from Works overhaul, did it go back to its previous depot or elsewhere, in effect, shuffling around to maintain numbers. I am talking here about what I would refer to as general purpose locos such as Halls and pannier tanks rather than the smaller classes which had specific duties. I suspect there will not be a definitive answer as I am sure some locos stayed at the same depot for many years.

The only way I can think of to research this easily would be the Irwell Press 'Book of....' series which I believe lists overhaul dates and shed allocations. Unfortunately, I cannot access mine at the moment as they all went into storage while I 'reallocated' myself to another county. I'm now a Western Region interloper on the Southern Region.

Of course, during the 1980's many loco and HST power cars stopped going off to Works for overhaul as we adopted the Level 5 Component Exchange Maintenance model where major components like power units and bogies were supplied to nominated depots to be swapped over.

Roy

The matter of which engines were allocated to which depot was a matter decided at a far higher level than at the individual depots concerned as many factors needed to be taken into account. These would have included:

ÔÇó The nature of the work that the depot had ie passenger, freight, expresses, secondary lines, shunting yard requirements etc
ÔÇó The numbers of each class of locomotive required to carry that work out
ÔÇó Known future changes (examples discussed below)
ÔÇó Maintenance requirements including main works overhaul and intermediate exams such as boiler washouts in steam days
ÔÇó The nature of the spares held at each depot for intermediate repairs

Going through that lot in reverse order, in a large depot such as Barrow Road, Bath Road or Old Oak Common it may have been possible to build in an element of slack for locomotives being stopped for repairs and even main works overhauls; in a small depot such as Yatton or Radstock or Templecombe it might not have been.

The nature of the work that a depot may have could have a seasonal element. For example, in steam days Crewe North dealt with all passenger work and Crewe South worked all freight. Allocation changes that appear in my allocations database shows that every spring there was a mass transfer of mixed traffic engines from South to North, and at the end of the summer timetable they were all transferred back again. More locally, towards the end Bath Green Park got an allocation of three 9Fs for the summer season, and this instruction was clearly written down somewhere because 3 were transferred there in 1963 when the reason for providing them, the heavy through passenger trains, had been diverted in the previous year.

There were of course some routes that required very specific classes of engines (eg something small, short and light enough to work the High Orchard line to Gloucester Docks or the china clay workings to Wenford Bridge), so these locomotives would certainly be returned to their normal depot after a major works overhaul.

However, if the locomotive was one of a common mixed traffic type such as a Hall or a Black 5, the likelihood would be that after a works overhaul the locomotive would have gone to whichever depot needed it the most, and not necessarily back where it came from.

Indeed, the same may have applied to some of the more specialised classes such as Kings ÔÇôif one came in to Swindon works from Old Oak and a substitute was sent to cover its absence, then when it came out again it could go to another depot that needed it.

Thanks for editing his out to a separate thread Robin.

Certainly in my time (blue diesels through to privatisation and beyond) each depot had a maintenance allocation. The availability target for service for each class was generally in the mid 80's percentage wise. As newer more efficient designs came along and maintenance practices improved, the targets were squeezed upwards. With some of the newer dmu's (Sprinters and Turbos) maintenance was encompassed within working diagrams with a time slot to complete the smaller exams and with the larger exams split into blocks of work known as balanced exams. On that basis, the number of units and number of diagrams were the same. It all sounded a bit theoretical to me but I think it worked reasonably well until a unit came out of service for maybe collision repairs for example.. It was probably a bit of a culture shock to the depots who had worked on the basis that once a loco/unit/set was stopped for maintenance, it was stopped for the duration until the work was finished. The focus of my job as a Maintenance Controller from the mid 80's onwards was to balance keeping on top of the maintenance programmes with having enough traction available for service. Trying to serve two masters as 'piggy in the middle' most of the time.

We also saw the concept of targets to complete routine maintenance. For instance, down at Laira we had two maintenance sets of HST trailer cars to cover the exam programme with one having to be released to cover a 'Friday Only' relief diagram, empty stock to Paddington to work one trip back to the West of England. For a time it ran for three days when we were providing a set for weekend Euston - Holyhead services. So production planning had to focus on completing an exam and the repairs arising between Monday and mid morning on Friday. There were also special event requirements where a maintenance set had to be released for the whole week. The two big ones which spring to mind are the very profitable Cheltenham race festival specials and Glastonbury, ferrying the 'Great Unwashed' to and from Castle Cary.

Roy

My reply dealt with what happened in steam days and up until 1976 when I left Bath Road. RoyÔÇÖs reply dealt with later years, and it is interesting to see how times have changed over the last 50 years.

Whilst it is true that locomotives were stopped for repairs for as long as it took, there would have been pressure from above of one was stopped too long without good reason. In the 60s with the transition from steam to diesel and the Beeching closures, it may not have mattered so much as the railway had more motive power than it knew what to do with, that situation rapidly changes, especially after the withdrawal of the hydraulics.

As I read RoyÔÇÖs account of repairs effectively being written into diagrams I was initially surprised but then remembered this sort of thing had been going on elsewhere for years. Some years ago I was watching a documentary on Routemasters, where a garage foreman said that these buses could go out in the morning peak, come in to the garage for an engine change, and be back out again in time for the evening peak. He also said that he couldnÔÇÖt do that with more modern buses because they had to take half of the back off to get to the engine... ÔÇ£ProgressÔÇØ is not always in the same direction

As a new thread has been started it seems only fair to wander off at a tangent again. One aspect which has intrigued me for years relates to what I will call 'transfer trips' by which I mean, if a locomotive is allocated to, say, Penzance and then is called into Swindon for a major overhaul or rebuild, how does it get there? If we are talking about a Hall or similar, presumably it could be put on a train - just double head something... but suppose the engine is 1338 working at Dunball Wharf near Bridgwater. Does some poor devil have to drive the thing from Bridgwater to Bristol say and get it serviced and then someone else drive it onwards the next day or would it have gone in a freight in light steam or what?

In approx 1959 or 1960 I visited Swindon Works where 2198, the last survivor of the B.P.& G.V.'s locomotive stud had just been outshopped and very smart it looked in BR black with the lion and wheel on the tank sides. On the way back to its home shed of Llanelly, it ran a hot box at Newport and was promptly withdrawn and scrapped. That means it must have travelled on its own wheels but doesn't say whether it was in steam or in a freight.

When 51218 was transferred from Bristol to Swansea, the rods were removed and it was included in the consist of a freight train.
The size of the tank prevented steaming that distance as a light engine movement.

On Wednesday afternoon trips round Swindon works, sometimes locos with just, three, two or even one digits were observed being overhauled. I don't remember road transport for locos back then, so presumably locos either worked or were towed to Swindon

51218 was indeed towed to Wales. It also ran a hot box and was stoppped at Gloucester for some time. All this was documented in the railway press bat the time.