SECTIONAL APPENDIX - YATTON


General and History

In 1841, the Bristol and Exeter Railway opened between Bristol and Bridgwater. The line was constructed as broad gauge. Near the village of Yatton, between Bristol and Weston-super-Mare, a station was build to provide service to the seaside town of Clevedon, this station was named Clevedon Road.
In 1847, a branch was build from this station to Clevedon, also as broad gauge, and the station was then renamed as Yatton. A new bay platform was added to the north side of the station to accommodate the branch trains.
Yatton became an even more important junction in 1869, when a branch was opened through the Cheddar Valley, to Cheddar and eventually to Wells. At Wells, this line connected to the East Somerset Raulway to Witham, providing a through route to Witham and beyond, e.g. to Frome and Trowbridge. This line, too, was constructed as broad gauge. Again a separate bay platform was created for the branch line services, this time at the south side of the station.
In 1876, the B&ER was amalgated into the GWR, and the GWR took over the running of the main line and the branches.
Between 1879 and 1882, all lines were rebuild to standard gauge.

As at so many locations, the decline came in the 1960s. The Cheddar branch closed to passenger traffic in 1963, and was closed completely in 1969. The Clevedon branch was closed in 1966. Both bay platforms were demolished.
The goods yard closed in 1965, and over time, all related tracks and pointwork was removed. The signalbox closed in 1972.

All that is now left is the station, as two platforms along plain track, and of all the intricate pointwork which existed earlier, only an emergency crossover now remains.

Adaptations
             
The simulation shows the layout as it was during the 1950s.
Note that pts. 76, 65 and 68 form a double slip. It is not possible to have simultaneous moves through 76 reverse and 68 reverse. Therefore, any route through 68 reverse requires 76 normal, and any route through 76 reverse requires 68 normal.
Lever 64 operated both the disk on the Middle Siding and the disk on the Cheddar Siding. In the sim, the latter is operated by lever 64A.
Lever 115 operated both the disk on the Up Main line and the disk on the west exit of the Up Sidings. In the sim, the latter is operated by lever 115A.
There were only very few track circuits in this area. The track circuits in the simulation are therefore not based on the real situation but have been set up such as to allow proper operation.

Local instructions
               
General information

The distance between Yatton West and Yatton East is very short.
As a result, on the Down line, the Yatton West distant is combined with the Yatton East Home. Therefore, for through trains, all signals at Yatton West must be cleared before TES from Yatton East is received to ensure the distant is cleared in time to avoid any unnecessary delays to approaching trains. For fast trains, it is advisable that the signals at Yatton West are cleared almost immediately after receiving the ILC request from Yatton East.
On the Up line, the OOS from Yatton East is received quite quickly after the train passes signal 118, and this signal must therefore be replaced to danger quickly after the train has passed to avoid an operator error. The distant signals combined with signals 120, 119 and 118 are controlled by Yatton East.

Shunt locations

At many signalboxes there were a number of locations in the area where trains could reverse for shunt workings, with permission to proceed to reverse provided not by signals but by instruction from the signalman, usually by showing a green flag. At Yatton, this applies for a number of locations as shown in the diagram. Permission for trains to proceed at these locations can be given through a series of buttons, displayed next to the levers. When a button is selected, a green flag is shown at the appropriate location, either the signalbox or the groundframe. Available routes from these locations and the related locking details are shown in the locking table. Note that these permissions operate in the same way as for signals, in that when permission is granted, all related switches are locked and other routes which would conflict with the permission are also locked.
For the flags controlled from the signalbox, these flags for the various locations are shown at different positions at the signalbox. It is possible for multiple flags to be displayed at the same time, except for the locations at the Cheddar Bay and the Middle Siding which are mutually excluding.


Fringe boxes

Distance to fringe boxes (distances from Yatton West box) :

Yatton East    :    48c
Huish Crossing : 1m 56c
Congresbury    : 1m 44c
Clevedon       : 3m 29c

General instructions

Rules to caution trains.
For semaphore signalling, the rule (rule 39A) applied that for a sequence of signals which had no intermediate or combined distant signal, if the last signal in this sequence could not be cleared, all preceding signals had to be kept at 'danger' at the approach of the train and could only be cleared if the speed of the train was sufficiently reduced. For the simulation, the speed must be reduced (to about 10 mph on approach). The speed while passing the signal must not exceed 15 mph.
See the locking details for the list of signals and conditions where and when trains must be cautioned. Note that the cautioning does not always apply for shunt moves which are wholly within the station area.

Locking rules.
For locking rules please see locking table.

FPL.
Facing Point Locks (FPL) have been provided where these were installed - see Locking information for details.
FPL's normally stand 'out', i.e. the normal position of these levers is 'reverse', in this position the linked switches are locked. To operate the switch, set the FPL lever to 'normal'. Once the switch is thrown, return the FPL lever to 'reverse'. FPL levers are locked in 'reverse' if a route is set over the switch on which they operate, or when this route is occupied. If an FPL is in 'normal' position, all routes over the related switch are blocked and signals can not be cleared.
Note that if an FPL operates on a switch which is part of a crossover, these rules generally also apply to the other switch of this crossover even if the FPL does not work directly on this switch; some shunt moves are exempt from this rule.

Notes on shunting
The 'shunt' command must be used if a train is to reverse at a particular signal. It is good practice to issue the shunt command before clearing the last signal which leads to the location where the train is to reverse, this in order to avoid 'overshoot' when the shunt command is issued too late for the engine to brake in time, which will result in the engine running past the reversal point up to the next signal.
The 'shunt' command can be issued for a train waiting to depart as issuing this command does not affect the timed departure of this train. However, the shunt command must NOT be used for a signal which is beyond a booked station stop before the train has come to a stand for that specific station stop. Setting the shunt command before the train has stopped will cancel out the station stop, and will lead to an error on missed station stop.
 
If an engine is to be attached to a train, it has to be terminated before it can do so.
If the engine is terminated in the same location as the train to which it is to be attached, it will stop short of this train. After the engine has terminated and is redescribed to a 0Z** number, it can be moved onto the train using the 'proceed' command, and can then be coupled to the train using the 'couple' command.
If the engine is terminated in another location and is moved onto the train while it already has a 0Z** number, it will move up to the train and can then be coupled using the 'couple' command.

Special locations

A number of additional timetable locations have been defined to allow better control of trains and shunt movements.
These locations are :

Turntable
Loop Siding
Spur
Middle Siding (between flag position and buffer)
Cheddar Siding
Down Goods (at signal 19)
Up Relief (at signal 121/122)

Section lengths

The list below details the lengths of platforms and sidings etc.
The length is defined in units, each unit equals an engine, a passenger coach, or 3 wagons.
             
Down Platform                                    : 7 units
Up Platform                                      : 7 units
Clevedon Bay (between buffer and signal 49)      : 4 units
Cheddar Bay (between signal 27/70/71 and pts. 63): 4 units
Cheddar Bay (between pts. 63 and buffer)         : 1 unit
Middle Siding (between pts. 63 and signal 64)    : 2 units
Middle Siding (between flag position and buffer) : 2 units
Cheddar Siding                                   : 4 units

Spur         :  2 units
Loop Siding  : 18 units
Turntable    :  1 unit

Shunt locations :
between sigs. 19 and LOS         :  4 units
between sigs. 2 and LOS          :  4 units
between sigs. 118 and 22         :  6 units
between sigs. 118 and 35         : 16 units
between sigs. 67/81 and 29/30/34 : not enough space for any unit
                                   for reversing at 81, 29/30/34 must be
                                   cleared
between sigs. 69/112 and 18      : 21 units
between sigs. 121/122 and 123    : 14 units
between sigs. 44/45 and 88       :  1 unit
between sigs. 48 and 14          :  2 units





Speed Restrictions

Main lines           : 75 mph
Cheddar Branch       : 35 mph (25 mph through Congresbury)
Clevedon Branch      : 45 mph
Down Goods           : 30 mph
Up and Dn Relief     : 30 mph
Points, sidings etc. : 10  15 mph
                                                  
Train Reporting Numbers

Train reporting numbers only came into use in later years, and also changed over the years. See timetable information for details.

Opening Picture

The opening picture shows an unidentified standard class 3 2-6-2 tank engine, bringing its Cheddar Branch train into the Up Platform. Note the signalman waiting to be handed the single line token.
The double signal on the left is signal 72/73, the line crossing immediately in front is the line to the goods shed. The signal further away in the distance is signal 10/74. The signal just above the luggage van is signal 29/30/34, and the signal just to the right of the engine is 120 with the Yatton East distant.                                                              
The picture was obtained through Colour-Rail (www.colourrail.com).

Acknowledgements

Thanks to PCRail-Test team for their help in testing this simulation, and as ever to John Dennis for providing the basic program for the heritage simulations.





             
