Personally, I find the use of big tender locomotives on what were small branch lines totally unrealistic. I remember the West Somerset in the dog days of BR steam when the services were hauled by pannier tanks, so I was most disappointed on my visit to the preserved line to find everything being hauled by hulking great tender locos as though everything was a through service from Paddington. Not only does a tender loco pulling a short rake of coaches look totally unrealistic, but also the big locos are pulling nothing like the load they were intended to pull, and consequently sounding nothing like a loco working hard.
Again, on my recent visit to the Bluebell, almost everything seemed to be tender locos. I hope the management noticed just how popular Fenchurch seemed to be with the youngsters, compared to the boring black hulks. When I visited as a lad, Bluebell and Stepney used to be the stars of the show, but now they have been sidelined in favour of the big willy-wavers.
I was very pleased on my recent visit to the Llangollen to find that we were being pulled by a pannier tank that sounded like it was earning its keep, rather than some incongruously large tender loco sounding like it was taking a boring stroll round the park.
The issue is with running smaller engines is they tend to set more fires and they can’t haul as much. In the case of Fenchurch (and Stepney) the weight limit to East Grinstead is 85 tons tare, and even the B Set at this time of year is easily double that. The Ps are even lower than that, at 70 tons tare. You then have a Standard 4 Tank, which is 300 tons tare. You can see why smaller engines aren’t prioritised.
In the off season when the weather is not so warm, an engine like Fenchurch is perfect for a short and light B Set, but from about late March until mid October that would put a serious strain on capacity. The BR engines are also easier to run and maintain. It’s a difficult balance between nice to have, popular and practical.
Tank engines like the E4, the North London Tank, the H, the Adams Radial and (when it’s finished) the Standard 2 Tank are the perfect size for a B Set tank engine, but unfortunately they are all either out of traffic or under overhaul.
However, I do agree that the wide collection of engines the Bluebell has should be highlighted, rather than focusing on the 50s and 60s. Out of our 6 currently operational steam engines, 4 of them are in BR livery, although they have all been built or rebuilt post 1948. A far cry from the days when there were 14 engines in traffic, with a much greater variety of motive power.
Just quickly about Stepney and Bluebell - Bluebell is currently undergoing a rather costly overhaul as there were more issues than previously thought, and Stepney will need new frames at the least - the engine will need a very large sum of money spent, which the railway does not currently have. Perhaps for Bluebell 100

.