Class 13's
Were 12 wheels better than 6? The class 13's
One of the more unusual units to visit Barrow Hill was a Class 13. The British Rail Class 13 was a type of diesel-electric shunting locomotive. The type was designed in 1965 because of the need to provide more powerful shunters for the Tinsley Marshalling Yard. Because of Tinsley's status as a hump yard, it was not possible to use a single locomotive owing to the risk of grounding. So, to achieve the required power, a pair of Class 08 shunters were permanently coupled in 'master and slave' formation, with the slave unit having had its cab removed. Both units were then ballasted to improve traction. Initially coupled cab-to-cab, it was found more practical to couple master nose to slave cab.
The yards at Tinsley were home to the unique hump shunters, the class 13s. Being delivered in May, June and July 1965 they were converted from six class 08s, 1-D4188 (M), 1-D3698 (S), 2-D4190 (M), 2-D4189 (S), 3-D4187 (M), 3-D3697 (S) & renumbered to D4500 (1 & 1), D4501 (2 & 2) & D4502 (3 & 3). During conversion then renumbered again in 1974 to the class 13s. D4500 becoming 13003, D4501 was 13001 and D4502 – 13002.
The need for the locomotives was confirmed by trials carried out during 1964 utilising two class 10 shunters and a train of short wheelbase heavy wagons. The train was started on the 1 in 260 gradient in the reception sidings but, when stopped at the hump signal, could not always get the train moving again, which was by then on a 1 in 40 gradient. Several times the weight of the heavy train would push it backwards against fully braked wheels. This was when the decision was made to proceed with the conversions. The idea was for two to be in continuous use on the hump with the third kept as a spare against failures (which were few), routine maintenance time and visits to works.
These locos were basically two 08s coupled together on a semi permanent basis but with just one driving cab (the master) giving an 0-6-0+0-6-0 wheel arrangement. Adhesion improvements consisted of thicker & deeper buffer beams at both ends and weights added above each intermediate wheel putting the total weight up from 51 tons to 60 tons. Another modification carried out to the 13s was the fitting of a 4 link screw coupling between the units to relieve the stress on the fixed draw bars.
An interesting footnote to this article is that one of these units visited Barrow Hill Roundhouse in 1981 as can be seen in the recently discovered photograph below. We have no information about the reason for the visit and frustratingly we cannot see the number. We wondered if it was the 13002 which had failed and was awaiting either repair or transfer to Swindon, the timing is about right. Thanks to feedback from one of our readers, Aston, we now believe it to be 13001.
An extra fitting in the cabs was a radio to communicate with the main control tower and repeat signals of the hump aspects. Call signs for each unit as follows:-D4500 was ALPHA, D4501 was BRAVO and D4502 was CHARLIE. When first converted the driving cab was in the centre of the units which was OK when humping at 1.36 MPH but not very good for travelling back down the yard due to the visibility being very poor (like a class 20 running nose first).
This problem was emphasised by the buffer stop on the reverse spur being pushed off its mounts several times with the M&S being derailed. Improvements for this problem happened in 1966/67 when the master units were turned and the cab positioned at the furthest end from the hump. The jumper cables also had to be re-routed and this work was carried out by Doncaster works with D4501 done in October 1966, D4502 by the end of November 1966 and D4500 in January 1967.
The vacuum brake system was retained but rarely used, occasionally in action on enthusiasts specials that traversed the yard. As said earlier, failures of the 13s were rare but occasions did happen and when this did occur it would not be unusual to see a pair of 08s or, on at least one occasion a slow speed 47 being used. Now that was a sight!
The three units had always stayed together as pairs, not once did a swap around between either the masters or the slaves ever happen. Visits to works for overhaul and tyre turning were made for 13001 in 1969 and 1976 at Doncaster, for 13002 in 1970 and 1977 also Doncaster and for 13003 in 1972 at Doncaster & 1980 at Swindon.
Several months of use found tyre wear with several flats on the flange tips spreading and increasing in size. This was caused by continual running over the Dowty system in the yard. The decision to modify the tyre profile to give up a quarter inch wide flat and monitoring found it alleviated the build up of displaced metal on the tyre flange sides. This work was once again carried out at Doncaster with the 13s running to the works and back under their own power.
In April 1981 the main generator of 13002s slave unit failed completely which meant a visit to works but due to the downfall in freight traffic it was decided that two humpers would be sufficient and 002 was withdrawn from traffic and sent to Swindon as stored unserviceable. 13002 was later cut up on sight at the works, finally being no more by 13th October 1982. 13001 carried on working until withdrawn in January 1985 and sent to Swindon, being cut up by 15th May 1985, 13003 was sent to Doncaster in February 1985 and chopped by May of that same year.
So that ended the unique class 13s but I remember them well, spending many break times in the summer months watching the 13s go about their duties, day after day, week after week, plodding up and down the reception sidings with just the occasional foray and break from routine.
One that springs to mind is of an ailing class 46 struggling to restart its train on the gradient up from Treeton junction with a trail of sparks around every driving wheel. I think it was 002 that was sent down over the viaduct to give it a good old push up the backside all the way through the yard. The 46 finally coming on shed for attention. Another nice sight was again 002 at the head of an enthusiast’s special having taken over at Rotherwood sidings. So the answer to the title of this article is an astounding “YES”.
Phil Hodgkiss
Thanks to Brian Williams for this photograph