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Section 20: Indicators associated with Train Dispatch

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Special indicators to assist with train dispatch duties are often provided within station areas. Some of these indicators work in conjunction with signals, while others are operated by the guard or platform staff.


Indicators for the guidance of staff carrying out train dispatch duties may need to be provided on station platforms, if the platform starting signal is not visible from the dispatch position. From at least 1928, the Southern Railway provided indicators for this purpose, showing either "On" or "Off". The indicator would show "On" [20.1] while the relevant signal displayed a 'stop' aspect, changing to "Off" [20.2] when the signal cleared to a 'proceed' aspect.

[20.1] "On" Indication. Click Here for Photo
Area: Predominately Southern Railway   Usage: Medium   Status: Obsolescent
[20.2] "Off" Indication. Click Here for Photo
Area: Southern Railway (subsequently All Areas)   Usage: High   Status: Current

On both the LNER and the LMS, the equivalent of the Southern Railway's "On"/"Off" indicators (see [20.1 & 20.2]) was an electric repeater that displayed a green light [20.3] when the relevant platform starting signal was 'off'. No indication was shown while the signal was at 'danger'.

[20.3] Green Light Indication.
Area: LNER / LMS   Usage: Medium   Status: Historical

The LNER and the LMS provided indicators at or near certain platform starting signals, which the guard operated to inform the driver that station duties were complete and the train may depart. When operated, and provided the signal concerned was 'off', the indicator displayed an illuminated letter "S" (for 'start') [20.4], accompanied by a high frequency buzzer or bell.

[20.4] "S" Indication.
Area: LNER / LMS   Usage: Medium   Status: Historical

From 1942 on the Southern Railway, the "On" indication (see [20.1]) was deemed unnecessary and was removed as a wartime economy. In future, only an "Off" indication (see [20.2]) would be provided, the indicator being extinguished when the relative signal displays a 'stop' aspect. This subsequently became standard throughout British Rail.


"Off" indicators are often double-sided, in which case the rear-facing side may show an amber coloured indication [20.5]. This also applies to an "Off" indicator provided on the back of a colour light signal at places where a train may stand with the front of the train beyond the signal. In these circumstances, the rear "Off" indicator controls the starting of the train.

[20.5] Rear-facing "Off" Indication. Click Here for Photo
Area: All Areas   Usage: Medium   Status: Current

When a rear "Off" indicator refers to a signal that can display both main and subsidiary aspects, it may have associated with it an additional indication reading either "Main" [20.6] or "Sub" [20.7], as appropriate. Alternatively, the indicator may display just "Off" for a main aspect and "Sub" for a subsidiary aspect.

[20.6] "Main Off" Indication.
Area: All Areas   Usage: Medium   Status: Current
[20.7] "Sub" Indication.
Area: All Areas   Usage: Medium   Status: Current

An alphanumeric route indicator may be associated with an "Off" indicator to repeat the route indication displayed at the signal when a 'proceed' aspect is shown [20.8]. This most commonly occurs in the case of a rear of signal "Off" indicator.

[20.8] Route Indication associated with "Off" Indication (e.g. "F" = Fast Line).
Area: All Areas   Usage: Medium   Status: Current

A 'right away' indicator is used at places where the driver may be unable to see the 'ready to start' handsignal. The 'right away' indicators provided on the Great Western Railway (e.g. at Bath Spa station in 1947) displayed the legend "RA" when illuminated, the letters being arranged vertically, one above the other [20.9]. Later "RA" indicators had the letters laid out horizontally, in either amber [20.10] or white [20.11].

[20.9] "RA" Indication.
Area: GWR   Usage: Low   Status: Historical
[20.10] "RA" Indication.
Area: Western Region (subsequently All Areas)   Usage: Medium   Status: Current
[20.11] "RA" Indication. Click Here for Photo
Area: All Areas   Usage: High   Status: Current

'Right away' indicators displaying a single illuminated letter "R" [20.12] were used on the Scottish, North Eastern, Eastern and London Midland Regions. A rear-facing "R" indicator may show an amber coloured indication [20.13]. The two-letter indication "RA" was preferred on the Western Region, where the indication "R" was commonly used in alphanumeric route indicators (see Section 6) to refer to a 'Relief Line'. The "RA" indication (see [20.11]) became standard on all B.R. regions c.1990 and is gradually replacing the former "R" indication.

[20.12] "R" Indication.
Area: Various   Usage: High   Status: Obsolescent
[20.13] Rear-facing "R" Indication.
Area: Various   Usage: Medium   Status: Obsolescent

In 1973, a pair of illuminated indicators was provided on the post of the Down Main Home signal at Stourbridge Junction North, for use when an assisting locomotive had been attached to the rear of a train. One of these indicators was a "right away" indicator displaying a letter "R" (see [20.12]) and the other displayed the letters "RS" [20.14]. Illumination of the "RS" indicator was an indication to the driver at the front of the train that the assisting locomotive at the rear was ready to start. The "RS" indicator was illuminated after the secondman of the assisting locomotive had pressed a plunger located some distance in rear of the signal and only once the signal had cleared. On seeing the illuminated "RS" indication, the driver or secondman of the front locomotive was required to press a plunger situated at the signal which, after thirty seconds had passed, illuminated the "right away" indicator on the signal post, as well as a double-sided "right away" indicator provided 356 yards in rear. The train could then proceed. Similar equipment was introduced at Hamstead Tunnel in 1983, at signal NS283 on the Up Soho line.

[20.14] "RS" Indication.
Area: Stourbridge Junction North / Hamstead Tunnel   Usage: Low   Status: Historical

On a bi-directional line, it is necessary to specify to which signal or direction of travel an "Off" indication applies. A plate may be fixed to the indicator, stating the signal number [20.15] or the direction of travel (i.e. 'Up' or 'Down') [20.16] to which it refers. Alternatively, an "Off" indication, when illuminated, may be accompanied by an illuminated legend "Up" or "Down", which may be abbreviated as "U", "D" or "Dn" [20.17 & 20.18]. On the Scottish Region, the direction of travel was not specified, but instead an indication "N", "S", "E" or "W" (i.e. north, south, east or west) showed at which end of the platform a 'proceed' signal aspect was being exhibited [20.19].

[20.15] "Off" Indication (e.g. applies to signal number D142).
Area: All Areas   Usage: Medium   Status: Current
[20.16] "Off" Indication (e.g. applies to Up direction signal).
Area: All Areas   Usage: Medium   Status: Current
[20.17] "Off" Indication (e.g. applies to Down direction signal).
Area: All Areas   Usage: Medium   Status: Current
[20.18] "Off" Indication (e.g. applies to Up direction signal).
Area: All Areas   Usage: Medium   Status: Current
[20.19] "Off" Indication (e.g. "N" = applies to signal at north end of platform). Click Here for Photo
Area: Scottish Region   Usage: Medium   Status: Current

Inner and outer platform starting signals exist on Platforms 2 and 3 at Brighton station for departing trains. Separate "Off" indicators are provided for each signal, displaying "Off Inner" [20.20] or "Off Outer" [20.21], as appropriate.

[20.20] "Off Inner" Indication. Click Here for Photo
Area: Brighton   Usage: Low   Status: Uncertain
[20.21] "Off Outer" Indication. Click Here for Photo
Area: Brighton   Usage: Low   Status: Uncertain

If a station is at or near a location where a reversal of Down and Up directions occurs, an illuminated "Down" or "Up" indication at an "Off" indicator (see [20.17 & 20.18]) is of no use in specifying the direction for which a signal is cleared at a bi-directional platform. The alternative employed in such situations is for the indicator to display the (suitably abbreviated) name of an important place in the same direction as the signal that is "off", either as an illuminated indication [20.22] or on a plate fixed to the indicator [20.23].

[20.22] "Off" Indication with Illuminated Direction Indication (e.g. "KLY" = Keighley).
Area: Various   Usage: Low   Status: Current
[20.23] "Off" Indication with Direction Plate (e.g. "COL" = Colchester).
Area: Various   Usage: Low   Status: Current

After platform staff had given the 'ready to start' signal to dispatch a train with power-operated doors, there was a chance that the train might depart with something trapped in the doors. To help avoid such an occurrence, a two-stage dispatch procedure for trains with power-operated doors was devised, entailing the use of 'close doors' indicators at certain stations where platform staff are on duty. When operated by the platform staff, a "CD" indication is displayed [20.24], indicating to the guard (or driver of a 'driver only' train) that station work is complete and the train doors can be closed. A "CD" indicator is usually combined with an "RA" indicator (see [20.11]), in which case the "CD" indication will be extinguished when the "RA" indication is exhibited. "CD" indicators were first introduced c.1990. A rear-facing "CD" indicator may show an amber coloured indication [20.25].

[20.24] 'Close Doors' Indication. Click Here for Photo
Area: All Areas   Usage: High   Status: Current
[20.25] Rear-facing 'Close Doors' Indication.
Area: All Areas   Usage: Medium   Status: Current

On platform lines that are subdivided by mid platform signals, an "Off" indicator (see [20.2]) associated with a mid platform signal would not usually be allowed to illuminate unless the signal ahead (at the end of the platform) is also 'off'. At stations where it is necessary to indicate that the mid platform signal alone is 'off', a supplementary indication is required to accompany the "Off" indication. This takes the form of an illuminated indicator that displays the number of the associated mid platform signal [20.26]. If the platform end signal subsequently clears, the signal number indicator is extinguished, leaving just the "Off" indication illuminated. These indicators were provided at Edinburgh Waverley station in 2006.

[20.26] Illuminated Signal Number displayed with "Off" Indication (e.g. applies to signal number 456). Click Here for Photo
Area: All Areas   Usage: Medium   Status: Current