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Section 10: Special Shunting Signals and Indicators

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At York No.1 Down South Yard (Hump Sidings), a position light shunting speed indicator was provided (along with a double-sided repeater), applicable to the Hump Shunting Line. The "proceed to hump summit at normal shunting speed" aspect was three white lights in the upper quadrant, as per [10.10]. The aspect meaning "proceed smartly towards hump summit" was three white lights, vertically displayed (see [10.12]). The 'stop' aspect comprised coloured lights on either side of the white pivot light [10.18], as did the aspect meaning "set back from the hump summit" [10.19].

[10.18] Position Light Hump Signal showing 'Stop'.	[10.19] Position Light Hump Signal showing 'Set Back from Hump Summit'.

When Glasgow Central station area was resignalled in 1960, special stencil type banner signals were provided on all the platform starting signals. These normally displayed no indication. When the main signal cleared to a yellow aspect (see [2.93]) and the banner was illuminated [10.20], it signified that a miniature yellow proceed aspect (see [3.73]) was being exhibited at the next main signal. The banner indication helped to ensure quick clearance of the platform line, particularly if the movement was being propelled.

[10.20] Stencil Type Banner Signal (Glasgow Central).

From around the mid 1960s, changes in goods traffic patterns rendered the large mechanised marshalling yards redundant. However, there was an emerging need for the rapid loading and unloading of long trains for carrying minerals, especially coal. The trains concerned need to be fitted with slow speed control. Special signals evolved for use at terminals where loading or unloading takes place under these circumstances. Usually, a series of identical signals are located at intervals along the line used for loading or unloading, all displaying the same indication at the same time. The signals are positioned in such a way that the driver always has a clear view of at least one signal at all times under normal conditions of visibility.

To deal with the loading and unloading of "Merry-Go-Round" (MGR) coal trains, the Scottish Region initially used colour light signals with special meanings. A green aspect [10.21] means "proceed forward". The train may proceed within normal visibility limits. A yellow aspect [10.22] means "proceed forward with caution at ½ m.p.h.". Slow speed control needs to be engaged, and the driver must be prepared to stop. A red aspect [10.23] means "stop immediately, even though not at signal".

[10.21] Loading/Unloading Signal showing Green Aspect (Scottish Region).	[10.22] Loading/Unloading Signal showing Yellow Aspect (Scottish Region).	[10.23] Loading/Unloading Signal showing Red Aspect (Scottish Region).

At certain installations, signals may display a flashing red aspect [10.24]. When this is displayed, the driver must stop the train (if it is moving) and set back at ½ m.p.h. At Monktonhall Colliery, the flashing red aspect was followed by a short steady red aspect (see [10.23]) on which the driver took no action. This was followed by a flashing yellow aspect [10.25] lasting about 6 or 7 seconds, then a steady yellow aspect (see [10.22]). The train must then stop reversing and obey the yellow aspect. Not every signal is capable of displaying each aspect mentioned above.

[10.24] Loading/Unloading Signal showing Flashing Red Aspect (Scottish Region).	[10.25] Loading/Unloading Signal showing Flashing Yellow Aspect (Scottish Region).

A series of special 'creep' indicators was installed at Fiddlers Ferry Power Station (London Midland Region) to control the unloading of coal trains. These displayed a vertical line of white lights for 'proceed' [10.26] or a horizontal line of white lights meaning 'stop immediately' [10.27]. If it was necessary for the train to reverse, a blue letter "X" would be displayed [10.28].

[10.26] Creep Indicator showing 'Proceed'.	[10.27] Creep Indicator showing 'Stop'.	[10.28] Creep Indicator showing 'Reverse'.

By 1969, a standard form of indicator for loading/unloading was in use. Three white lights vertically displayed (see [10.12]) means "move slowly in the normal direction for loading or unloading". Three flashing white lights at 45° [10.29] means "move slowly in the opposite direction to that required for loading or unloading". Three steady white lights at 45° (see [10.10]) means "prepare to stop", and three horizontal lights (red-white-red) (see [10.18]) means "stop immediately, irrespective of distance from the indicator".

[10.29] Loading/Unloading Indicator showing 'Reverse'.

At certain installations on the Scottish Region, the position light loading/unloading indicators did not display a "prepare to stop" aspect, and three steady white lights at 45° (see [10.10]) instead had the meaning "move towards the loading/unloading facility". Three vertical white lights (see [10.12]) meant "move away from the loading/unloading facility".

At certain locations on the Scottish Region, an indication "P" may be shown for propelled movements [10.30]. No propelling movement must be made beyond the signal concerned unless the "P" indication is displayed.

[10.30] "P" Indication (e.g. associated with shunting signal and route indication "F").

In a few places on the London Midland, Western and Southern Regions, indicators in the form of a white light [10.31] are provided to control movements setting back into sidings. There is a series of indicators provided at intervals along the line. If the white lights are extinguished, the setting back movement must immediately stop. On the Scottish Region, an indicator displaying the words "Set Back" performed a similar function [10.32].

[10.31] Set Back White Light.	[10.32] "Set Back" Indication (Scottish Region).

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