User:Rbaal/sandbox

Introduction
Russian railway signals are defined in the reference Ministry of Means of Communication of the Russian Federation, Instructions for Signalization on the Railways of the Russian Federation (Moscow: 2006)(in Russian) The purpose of railway signals is to guarantee the safety of movements, as well as the accurate organization of train movements and shunting operations. Railway signals may be classified as visual or audible. Most signals are visual, but audible signals are important in limited applications. Visual signals are principally light signals and wayside signs. Audible signals are principally the locomotive whistle and the detonator (torpedo). A second important classification is as fixed or movable signals. A fixed signal is anchored in the ground, and its position does not change. Hand and lamp signals are movable, as are locomotive and train signals. Temporary signals, though portable, should be considered as fixed signals. Locomotive cab signals are a special case; they are usually treated as fixed signals. They are used both as supplements to wayside signals, and as an independent signal system without wayside signals. Locomotives in Russia are equipped with headlights, which are illuminated by night but not by day (in the U.S. they are illuminated day and night). This permits the use of reflectorized signs, a very good idea. Pyrotechnic flares (fusees) are not used in Russia, although they would be very useful in snowy winter weather. The reason (as it is in Britain) is probably the fire hazard, though experience shows that this is minimal. A third classification is as day, night or 24-hour signals. Light signals are an example of the latter, while flag and lantern signals are used by day or night, respectively. Signals may also be divided into those which display more than one aspect, and those with only one aspect, which are essentially just signs.

There is some basic similarity to German practice, though the details are very different. The influence of American practice can also be seen in a few places. There is very little influence from British or French practice. Historically, German and American influence can be understood.

Automatic block was first installed in 1931, mostly with colour-light signals, and by 1937 was in service on 3,202 miles. At the end of the Second World War, most signalling and interlocking was still mechanical, but cab signals were introduced not long after, as well as centralised traffic control. Train movements are regulated by dispatchers. Buffers and link couplings have now been replaced by knuckle couplers.

Types of Light Signals
Russian signals are predominantly colour-light signals, called светофоры, "light-carriers", by analogy with семафоры. The lights are arranged in units of two or three lights, one above the other, with a black background. Relay (searchlight) signals are also found. One or more such assemblies make up a normal signal head. Signals have only one signal head. Multiple heads (as in the U.S.) or junction indicators (as in the U.K.) are not used. Signals may be on masts, as dwarf signals, on signal bridges or cantilevers. A signal stands to the right of the track it governs. There is no mention in the signal instructions of distinguishing a signal in an irregular position, either to the left, or beyond an intervening track. On double track, trains normally run on the right-hand line.

Where semaphores are preserved, they're aspects and indications are explained in the Instructions for the Movement of Trains.

The signal colours are red, yellow, green, lunar white and blue. An aspect usually shows one or two lights. Only one aspect displays three lights, the one that shows three yellow lights and indicates approach through a divergence to a red (stop) intermediate signal at not exceeding 20 km/h. Normally the lights are in groups of two, occasionally with a group of three on top. Flashing lights are used. Normally, a flashing light is less restrictive than a steady light of the same colour. A red light is always displayed alone, and always indicates stop. Flashing red lights are not used. Shunting signals display blue or lunar white. Blue prohibits movement, while lunar white permits it. There are both low and high shunting signals.

Signals are classified as to function as follows: entrance signals govern the admission of a train to a station; exit signals govern the exit of a train from the station to a block section; intermediate signals govern the motion of trains within a station; block signals govern the admission of a train to a block section, usually automatic block sections; covering signals protect crossings with other railways, tramways, and trolleybus lines, movable bridges and electrical conductors; barring signals, protect points of danger at level crossings, large engineering works and unstable areas, and barrier signals at structures for the inspection and repair of rolling stock in stations. There are also signals of the latter class resembling the German Gleissperrsignale, which are clearly analogous. There are also distant and repeater signals, locomotive (cab) signals, shunting signals and hump signals. Some signals may serve two or more purposes, such as entrance-exit, exit-shunting, exit-intermediate, etc. This classification is very similar to the German signal classification.

The fundamental aspects and their indications are as follows: one green light, proceed at normal speed; one flashing yellow light, proceed passing next signal at reduced speed; one yellow light, proceed prepared to stop at next signal; two yellow lights, the upper flashing, proceed at reduced speed on diverging route; two yellow lights, proceed at reduced speed on diverging route prepared to stop at next signal; one red light, stop and do not pass signal. The red aspect is shown alone and always means stop, though it may be modified by the call-on signal. Multiple red lights are never shown, nor red lights with other lights in aspects that allow the train to proceed. The green light is almost as positive in permitting a train to proceed.

signal that is not in service is marked by two boards forming a cross, and the lights are extinguished (Sec. 2.26). Automatic block signals are designated by numbers; all others by letters, or letters and numbers. In the illustrations in this article, the number plates are shown blank.

On double- and multiple-track sections, signs marking station limits (граница станции) are used, which may be lettered on both sides. On double-track lines, station limit signs are placed opposite the entrance and exit signals beside the other track. On single track, the entrance and exit signals mark the station limits. There is an important distinction between tracks in stations, and tracks between stations, in Russian signalling.

Entrance Signals


The entrance (входный) signal at a station gives the driver of an approaching train not only information on the state of the line ahead, but also whether the train will hold the main route or be diverted to a side track. If it is diverted, then the speed permissible in the turnouts should also be communicated. An entrance signal generally consists of two two-light units, the top displaying yellow or green, the lower red or yellow. It will be part of the automatic block system, displaying a green, yellow or red light depending on the state of the line ahead. One green light indicates that the next signal, which may be an intermediate signal or the exit signal, is not at stop, and at least two blocks ahead are clear. It also indicates that the main route is set. One yellow light (on the upper unit) indicates that the main route is set, and the next signal is displaying stop. One flashing yellow light indicates that the next signal should be approached at reduced speed, perhaps because there will be a divergence there. One red light, which will have been announced by the last signal in rear, means stop before passing the signal.

A yellow light will be shown on the lower unit if there will be a divergence on entering the station. If the upper unit shows a flashing yellow light, the next signal on the divergent route will not be displaying stop, and at worst may be passed at reduced speed. If the upper yellow is steady, this signal must be approached prepared to stop. If not otherwise specified, speed through the turnouts should not exceed 20 km/h. This speed is not specified in the rule book, but will be quite safe for a 1/9 or 1/11 turnout.

A greater permissible speed on the turnouts is indicated by green plates below the signal lights. A flashing green over steady yellow, with one green plate, indicates a divergence with a permissible speed of 80 km/h, with the exit signal clear (1/18 turnout). If there are two green plates, the speed is 120 km/h (1/22 turnout). A flashing yellow over a steady yellow with one green plate indicates the same speed, 80 km/h, on the divergence, but now the next signal must be approached with limited speed. If both yellow lights are steady, the speed must not exceed 60 km/h, and the train must proceed prepared to stop at the next signal.

One flashing green light indicates that the train will remain on the main track, but that the next signal (usually the exit signal) should be approached at not exceeding 60 km/h, expecting a divergence there.

The distinctive aspect of three yellow lights is used at certain stations as provided by special rules. It may be accepted only by multiple-unit (motor) trains, one-man locomotives, gasoline locomotives and track speeders. It allows them to follow similar movements with caution, and at not exceeding 20 km/h, on free track up to an intermediate signal displaying stop. This aspect may be displayed on entrance or intermediate signals. It is similar to the display of two yellow lights, except for the permissive characteristic, and the limitation to certain types of equipment.

A flashing lunar-white light displayed below the red light of a signal at stop, or below an extinguished signal, is a call-on signal that permits a train to pass the signal with caution at not exceeding 20 km/h prepared to make an immediate stop on encountering obstacles to further movement, up to the following signal, or to the boundary post on a route without an exit signal. Call-on signals may be used at entrance, exit (not group exit) and intermediate signals. Starting from a call-on signal at an exit signal is permitted only on double track with automatic block signals, and according to rule. The figure above illustrates the aspects displayed by entrance signals, for which the indications are as given above.

Intermediate Signals
Intermediate (маршрутные) signals are those between the entrance and exit signals on the route of a train within a station. The Russian name suggests the French marche-route, and a literal translation is "itinerary" signals, but this term is not used in American or British practice, where a "route signal" indicates which of two or more possible routes is selected. Intermediate signals display the usual single-light aspects with green, yellow, flashing yellow and red aspects with the normal meanings. Flashing yellow indicates that the next signal is to be approached at reduced speed, as usual. Two yellow lights, the upper one flashing, indicates that the signal is to be passed at reduced speed prepared for a divergence, but the next signal is off. Two steady yellow lights indicate that the signal is to be passed at reduced speed, prepared to stop at the station on a diverging track, with the next signal at stop.

lluminated route indicators at signals governing several routes are placed below the signal head. They may show direction by an inclined row of three white lights, or by a number or letter. Green lights displaying a number on a matrix below intermediate and exit signals give permission to proceed on the route indicated. For shunting movements, the lights are lunar white.

Exit Signals


The exit, departure or starting (выходный) signal authorises a train to leave a station and move into the block in advance. When the automatic block system is in service, the following aspects are used: one red light, stop, do not pass the signal; one yellow light, proceed prepared to stop at the next signal, one block clear ahead; one green light, proceed at normal speed, two or more blocks clear ahead. If speed must be limited on departure, two yellow lights are displayed. If the top yellow light is flashing, proceed at reduced speed on diverging route, next signal is off. If it is steady, proceed at reduced speed on diverging route prepared to stop, next signal is on. This recalls the German practice of using two semaphore arms to indicate proceed at reduced speed through turnouts, and one arm to indicate proceed on the main route.

The rule book does not specify the maximum speed for the divergence when the above aspects are employed, but a speed of 40 km/h (25 mph) would be safe with number 11 frogs (1 in 11). If the divergence can support greater speeds, the signals are modified by the addition of a green plate below the lights. Two yellow lights and a green plate specify a speed of 60 km/h (38 mph), appropriate for a no. 18 frog. This aspect also indicates to expect the next signal to be on, but it is no doubt used even when the next signal is off. If the upper light is replaced by a flashing green light, the speed is 80 km/h (50 mph). There is no aspect with a steady green light above a steady yellow light, which would seem to be appropriate when the speed is 60 km/h and the next signal is off.

If manual block is in use, the exit signal may be a two-aspect signal if no divergence is possible. A red light indicates stop, do not pass signal, while a green light indicates proceed at normal speed, block clear to next station. If a diverging route is set, two yellow lights authorise its use, and indicate that the block is clear as far as the next station. If the upper light is flashing, then the entrance signal at the next station is off, in addition.

Distinctive aspects are used where locomotive cab signals are an independent means of signalling. For straight-through movements on the main track, green over lunar white authorises a train to depart, with two or more block sections clear ahead. Yellow over lunar white authorises a train to depart, with only one block section clear ahead. Wayside signals are not used between stations, but block boundaries are marked with reflective numbers, and there may be telephones as well.

Where there are multiple tracks, or double track signalled in both directions, a train may regularly use a certain track. For example, with double track signalled in both directions, this may be the normal right-hand running track. When a train is signalled to leave a station on other than its normal track, green over green is used, and this guarantees that two or more block sections are clear ahead. If a train is signalled to cross over to the left-hand track on departure, the exit signal flashing yellow over lunar white is used, which prescribes a speed not exceeding 40 km/h through the crossover. If a train is to exit the station on a route without a block system, a single lunar-white light is displayed (in the lowest light). The driver must either have the train staff for this line, or a written permission to proceed. The aspects displayed by exit signals are shown above.

Block Signals


These signals are classified as проходные, which could be better translated as "running signals". They are the signals used between stations, governing the occupation of blocks, so they are called block signals here. They may be normally dark, illuminating on the approach of a train, and extinguishing after the train passes.

Where the automatic block system is in use, these are the familiar three-aspect automatic block signals, displaying aspects with a three-light head. Yellow is on the top, red on the bottom and green in the middle. Searchlight signals are also used. one green light, proceed at normal speed, two or more blocks ahead are unoccupied; one yellow light, proceed prepared to stop at the next signal, one block ahead is unoccupied; one red light, stop, do not pass signal. A flashing yellow or green light warns of a divergence at the next signal. A flashing yellow indicates that the next (entrance) signal should be passed at reduced speed. This signal will display either a flashing yellow over yellow, or yellow over yellow. A flashing green indicates that a speed of 80 km/h (no. 18 frog) or 120 km/h (no. 22 frog) is allowed at the entrance signal, which will display a flashing green and one or two green bars. A plate with three inclined bars identifies these signals, as shown at "e" and "f".

The positions of the red and green lights may be exchanged for four-aspect signalling. one yellow and one green light, two blocks are unoccupied ahead (illustration "d"). The other three aspects are the same as in three-aspect signalling.

In case of insufficient braking distance in advance of a block signal approaching an entrance signal, the fact is marked by two white plates on the mast below the signal lights, displaying arrows. The signal in rear of this one has a single similar arrow plate, to warn of the limited braking distance. These arrow plates are illustrated above.

Two-aspect signals are used with "half-automatic" block, which seems to be manual signalling with track circuits. One green light (a) admits a train to the block and shows that the block is clear to the next block post. One red light (b) indicates stop, do not pass signal, as usual. The distant signal shows green (c) when the main signal is open, yellow (d) when it is closed. Flashing yellow (e) indicates that the next signal is open, but is to be approached at reduced speed, and the train will be received on other than the main track. These signals are also used as exit or entrance signals when this signal system is in effect.

Conditionally-Permissive (Grade) Signal
Automatic block signals on a steep climb may display a reflective transparent-white reflective T on a black background in the form of a square standing on a point. This permits freight trains to pass the signal when it displays a red light at not exceeeding 20 km/h with caution, and prepared for an immediate stop on encountering any obstacle to its progress. This aspect is illustration "b" in the Figure. This is useful with plain bearings, whose static friction is much larger than the moving friction, making it difficult to start a train again when it has been stopped on a heavy gradient. This is not important with roller bearings, whose static friction is not large. The origin of the "T" is not stated, but it may signify a word derived from толкач, pusher or banking engine.

Covering and Barring Signals


Covering (прикрытий) signals are two-aspect signals. One green light: proceed at normal speed; one red light: stop, do not pass signal. These are preceded by a distant signal displaying yellow or green. Covering signals and their distant signals are exactly like two-aspect manual block signals. These signals are used to protect crossings at grade with other railways, tramways or trolleybuses, as well as movable bridges and other points of danger. These signals are illustrated above to the left. These signals are called Deckungssignale in German.

Barring (заградительный) signals have a single light in a square black background in the shape of a square standing on a point. This light is normally extinguished, and then the signal has no significance. When illuminated, the signal gives its specific indication. One red light: stop, do not pass signal. One yellow light: proceed prepared to stop at barring signal in advance. When one green light is shown, the signal is a repeater for the next exit or intermediate signal with a special use. The masts of barring signals are distinguished by diagonal white and black stripes. In German, these are Gleissperrsignale, though with a very different appearance. Repeater signals do not have distinctive masts.

These signals are illustrated at the above. Examples "a" through "c" are barring signals, while examples "d" and "e" are repeater signals. The unlighted aspects are shown for each type ("c" and "e"). These aspects represent a divergence from American and British practice, where a light signal not illuminated must be interpreted as displaying its most restrictive aspect. Here, it is simply ignored.

Distant and Repeater Signals
Distant (предупредительный) signals are used to govern the approach to entrance, block and covering signals where automatic block signals are not used. A green light indicates proceed at normal speed, main signal is off. A yellow light indicates proceed prepared to stop, main signal is on. A flashing yellow light indicates proceed at normal speed, entrance signal is off, but must be passed at reduced speed; train will be received on a side track at the station. Distant signals are two-light signals with green on top, yellow on the bottom, as illustrated above for manual block signals.

Repeater (повторительный) signals displaying one green light indicate that the exit or intermediate signal is off. Normally the lights are extinguished in these signals, and then they have no significance. A passenger train having a stop in a station may be started only if a green light is displayed in the repeater signal. If the green light cannot be displayed because the repeater or exit signal is faulty, written permission is necessary to pass the signal, as provided for in the regulations. The reason for this is that conditions may have changed during the time of the stop, and signals that were clear may now stand at danger. A repeater signal has a square background standing on a point.

Locomotive (Cab) Signals
Locomotive cab signals have five lenses in a vertical column, which can display the colours green, yellow, yellow/red, red and white, in that order from top to bottom. A green light indicates proceed, and the wayside signal also shows green. A yellow light also indicates proceed, and the wayside signal shows one or two yellow lights. A yellow/red light indicates proceed with caution, while the wayside signal ahead shows a red light. In case the red wayside signal is passed, the cab signal shows a red light. A white light indicates that the locomotive apparatus is functioning, but information is not being received from the track. The driver must proceed only as permitted by the wayside signals. The cab signal shows green also when the wayside signal displays a flashing green light, a flashing yellow light, or one green and one yellow light. It shows yellow when the wayside signal shows a flashing yellow light above a steady yellow light. When the cab signals form an independent means of signalling, the indications are somewhat simpler. A green light indicates proceed at normal speed, two or more block sections ahead are clear. A yellow light indicates proceed at reduced speed, one block section ahead is clear. A yellow/red light indicates proceed with caution in the block section, the block section ahead is occupied. The red light is shown if the train passes into an occupied block. The white light indicates that the system is working, but information is not being transmitted from the track to the locomotive. The train must then be governed by the wayside signals.

Shunting Signals


These signals permit or forbid movement on certain tracks within a station. They do not authorize train movements on main tracks. A train movement cannot ignore these signals, and cannot accept them for movements outside station limits. They are not used in American or British practice, where their functions are performed by ordinary signals, perhaps as low (dwarf) signals. The principal idea is to guarantee that they are not confused with running signals on main tracks, and do not distract drivers of trains. In American and British practice, this is done by placing them low, so they cannot be easily seen at a distance, and perhaps by using purple lights instead of red.

In Russian practice, blue and lunar-white lights are used, and exist as high as well as low signals. One lunar-white light permits shunting movements, while one blue light forbids them. Shunting movements may be permitted at intermediate and exit signals by displaying one lunar-white light, the red light being extinguished. In Russian practice, a red light may not be passed except in special circumstances (for example, with the flashing lunar-white call-on signal). With electrical illumination, blue lights can be made quite bright, but when oil lamps were used, blue lights were distinctly dim.

Group shunting signals govern more than one track. For example, one signal, located beyond the point where several tracks converge, may control movements from any of the tracks. These signals may display their aspects in one or both directions. Of course, if movements are possible on more than one track, some way of identifying the movement to which the signal is to apply must be provided. Normally, hand signals can serve this function. Recall that running signals always apply to only one track.

On single-track lines, as well as double track lines signalled in both directions, a shunting signal on the mast of the entrance signal may authorize shunting movements as far as the station limits with a lunar-white light.

On secondary railways, in cases of necessity, shunting signals may display red instead of blue lights. At stations with centrally electrically-controlled switches and signals, if necessary the aspect of two lunar-white lights may be used, indicating that shunting movements may proceed on the track protected by the signal, and that the track is unoccupied.

In the absence of shunting signals, passing exit or intermediate signals displaying a red light by shunting movements must be authorized by the assistant station-master or his designated shunting foreman personally, by radio, a two-way communication device or by a signal given by a hand-signalling device.

Pushing on gravity sorting hills (humps) is governed by three-aspect signals exactly like block signals. From top to bottom, the lights are yellow, red and green. The red light indicates stop. A green light indicates push at greatest speed, a yellow light push at slow speed, and yellow and green simultaneously displayed, push at an intermediate speed. When the red light is shown together with the letter H illuminated on a 4 x 7 matrix of white lights, the indication is to draw back the wagons to the reception yard or the escape track. This signal is probably located at the top of the hump, where it can easily be seen at a considerable distance.

Protecting Signals


Protecting signals are signs used to control the approach where reduced speed or a stop are required. They display only one aspect, which does not change. They may be permanent or temporary. Temporary signals are usually on a pointed staff that can be held in the ballast, so that they may be placed where desired. In the illustration at the right, "a" and "b" are permanent, while the others are temporary. A red flag may also be used for the stop sign, and by night a red light is displayed instead.

Sections requiring reduced speed because of a danger are marked at their limits by permanent wayside signs consisting of a black circle on white background with a horizontal or vertical black bar, and reflective cat's eyes. The horizontal bar identifies the beginning, the vertical bar the end of the section. The two sides of the signs display opposite aspects. These resemble the Sperrsignal-type aspects mentioned above. These are permanent signs, not temporary ones used to protect work sites (yellow and green discs). A similar signal, but with a black square and horizontal or vertical black bar on a white background, labelled "карст" is also found, often on catenary supports. Karst is a limestone area with subsurface drainage that is subject to subsidence. There are also hazard signs that are black squares with a diagonal line on a white background. Above the diagonal line, a "!" is shown, and beneath it "газ" (gas) or "нефт" (crude oil). All these signs simply recommend increased vigilance in the danger area.

The arrangement of permanent protecting signals on single and double track lines is shown at the right. A = 800 m is adequate for passenger trains at 100 km/h, 1000 m for 140 km/h, and 1400 m for 160 km/h, on level track.

The temporary yellow warning sign is always used with detonators (torpedoes) accompanied by a flagman, when between stations. The point of restriction is marked with a red stop signal. Distances from the detonators to the stop signals is somewhat greater than with permanent signals. As usual, three detonators are used at a spacing of 20 m between them, two on the right-hand rail alternating with one on the left-hand rail. The reason for this extra precaution is that temporary restrictions, while often announced in bulletins, are always unusual and otherwise unexpected. Temporary whistle posts may also be used, where a stop is not required, for the purpose of warning workers on the track. On double track, this is done at a point opposite a restricted section on the other track. The green warning sign is on the reverse of the yellow one. If no speed restriction is bulletined for a yellow sign on other than the main track between or in stations, a speed of 25 km/h is applicable.

The rear of a train stopped on a main track may be protected by three detonators 800 m to its rear, spaced 20 m apart on opposite rails, accompanied by a flagman with red flag or lamp 20 m from them toward the train. The explosion of a detonator is always a signal to stop immediately. Similar measures are used to protect trains on a parallel track that may be affected by an incident.

Other Signals and Signs


Turnout and derail indicators are illustrated at the left. The turnout indicators have narrow and broad sides. When illuminated, the narrow side displays a milk-white rectangle and the broad side a yellow disc. There is no special indicator for slip switches; two ordinary indicators are used in this case, one at each end. If both show the same, the switch is set for straight-through movement; if different, for a diverging movement. Unlighted indicators use the rather American-looking arrow, which points in the direction of divergence, and is not visible when the turnout is set for the straight route. The third indicator is exactly like a German Sperrsignal. The translucent background may be illuminated internally. The bar is not movable, but is in a different position on two adjacent sides, so the aspect is changed by rotating the indicator, as in the case of the other two signals. Of course, when used at a buffer block at the end of a track, it is fixed showing a horizontal bar,and displays only on the side of the track. It is mounted on the right-hand side of the stop beam, as seen from the approach. A turnout indicator can also be used for this kind of signal, with the vertical bar on the narrow rectangular side and the horizontal bar on the wide circular side.

Fouling points at converging tracks are marked by concrete posts as illustrated at the right. Example "a" is the usual post, while "b", with a spiral painting, is used at main tracks and receiving tracks.

Flanger signs are temporary, erected during the snow season. Sign "a" in the Figure at the left advises that the flanger should be raised and the wings closed. For normal snowploughs, it is located 30 m from the point of the obstruction, usually a level crossing. For high-speed snowploughs, it is placed 50 m from the point of obstruction, and is preceded by the warning sign "c" at a further distance of 100 m. Sign "b" indicates that the flanger may be lowered and the wings opened. It is placed 10 m beyond the point of obstruction. In case the flanger must be raised at more than one closely-following points, a double signal like "a" is used. Snowploughs display two yellow flags by day, two yellow lights by night, above the level of the plough blade. If running on the wrong line, an additional red flag or light is displayed below the left-hand yellow flag or light. A locomotive preceding a snowplough displays the same flags or lights, but at the buffer beam. One might wonder what the purpose of these yellow signals is, since the vehicle is clearly a snowplough and similar signals are carried by nothing else. Perhaps they distinguish between a plough in service and one merely being moved. Train signals are very simple. Locomotives display a single headlight by night, which is extinguished by day. Also by night, a locomotive on a train displays two white lights near the buffer beam. If running against the current of traffic on double track, the left-hand light is red, and the lights are displayed by day as well as by night. Freight cars being pushed by day display no lights or flags on the front, but display a white lantern near the buffer beam by night. If running on the wrong line, an employee displays a red flag or a red lantern from the leading car. By night, a white lantern is displayed near the buffer beam. A freight train displays a reflective red disk as a marker at its tail. Passenger, postal and parcels trains display three red lights on the last car (two above, one low on the right). A locomotive pushing a train displays a red light near the buffer beam, on the right facing the locomotive. At a station, part of a freight train displays a yellow flag by day and a yellow lantern by night near the buffer beam.



The whistle post (предупредителный сигнал знак С), is erected approaching tunnels, bridges, railway crossings at grade and so forth. The "C" stands for свисток, "whistle", which must be sounded at that point. The lack of any mention of highway level crossings suggests that these matters are treated in special instructions.

Another signal of this same classification has "остановка локомотива", stop for locomotives, lettered in black on a white background with a black border. The track beyond this sign may not be used by locomotives for various reasons, usually because of construction or light structure. Lengths for automatic brake tests may be marked by square signs. A sign with a red border and red "HT" (начало торможения) marks the point where brakes should be applied, and a sign with a black border and black "KT" (конец торможения) the point where they should be released.

Water columns are still in the rule book. The horizontal delivery pipe is painted red. A lantern on top of the column displays red in both directions when the delivery pipe is perpendicular to the track, white in both directions when parallel to the track.



Electrical signs are placed on the catenary supports. The first two mark the location of a contact wire gap. The one labelled "begin" is opposite the gap, while the other is on the next support beyond the gap. The next three are concerned with the handling of the pantograph, and are: "a", prepare to lower pantograph; "b", lower pantograph; "c", raise pantograph. These are blue when temporary, protecting work on the contact wire, but have black backgrounds when permanent. The final three are concerned with handling of the main switch, and have a blue background even though permanent. "d" is switch out, "e" is switch in, and "f" is switch in for electric multiple unit trains. While "e" is located not less than 50 m from the end of the gap, "f" is not less than 200 m. The reason for this is that electrical multiple units usually have more than one pantograph, and they must all be clear of the gap before the main contactor is closed again, to avoid connecting the two sections of the contact wire. There is no sign announcing the end of the contact wire. There is also an illuminated signal for lower pantograph, used approaching insulated gaps in the contact wire on direct-current lines. If there should be a sudden loss of voltage in a section, a train must not be allowed to enter with raised pantographs. This signal is a flashing white bar in a square black background, standing on a corner, with a white border, mounted on the catenary supports or on separate posts. If the bar is not illuminated, the signal has no significance.

Hand Signals and Acoustical Signals
By day, a red flag held out at arm's length, and by night a red light, indicate Stop. If red signals are not available, a yellow flag, the hand or any object by day, or a lamp of any colour by night moved in a circle at arm's length has the same meaning. Yellow flags and lights held out at arm's length indicate Reduce Speed. If the speed is not specified in special instructions, not above 25 km/h. If yellow signals are not available, the hand or white light moved up and down at arm's length has the same meaning. The hand or white light moved up and down is a signal to the driver to apply brakes (for a static brake test); the driver responds with one short sound of the whistle. The hand or white light moved from side to side is a signal to the driver to release brakes, acknowledged by two short sounds of the whistle. To signal a train to start, by day a white target on a handle (or a furled yellow flag), and by night a green light, are held high in the right hand. The same signal is also made to a train passing without stopping. Red signals are used to stop a passenger, postal or mixed train at an unscheduled stop. The person with the duty of meeting and conducting trains at a station must wear a hat with a red top (the uniform hat is blue). The hand signal for "lower pantograph" consists in raising the left hand above the head, and moving the other one horizontally from side to side, by day. By night, the signal is given by a white lantern, first moved vertically, and then from side to side. This is answered by a whistle signal, as mentioned below.

Acoustical signals are expressed by the number and arrangement of sounds of different lengths. Their meanings by day and night are the same. Because they actively attract attention, they are particularly useful as emergency signals. They may be given by locomotive whistles and the equivalents on other stock, hand whistles, mouth horns, sirens, horns (hooters) and detonators (torpedoes), which are called петарды in Russian. The explosion of a detonator demands an immediate stop. Three short sounds is a signal to stop. One long sound is a signal that the train is departing. Three long sounds is a signal to apply brakes, and two to release them. These are given by the driver of the leading locomotive, and repeated by the driver of the second locomotive, when double-heading.

There are other signals for communication between the drivers of double-headed and pusher locomotives. Shunting signals are given with an unfurled yellow flag by day and a white lantern by night, and with a whistle or horn. A flag or lantern moved from side to side over the head is a signal to go forward; the acoustical signal is one long sound. If the flag or lantern is moved from side by side below the waist, it is a signal to go back; the acoustical signal is two long. The flag or lantern moved up and down at arm's length means go slow, gently, and the audible signal is two short sounds. For stop, the flag or lantern is moved in a circle at arm's length, and the acoustical signal is three short sounds. The sounds are repeated by the locomotive whistle. The "notification" (оповестительный) whistle signal is one long sound, or when moving against the current of traffic, long-short-long. It is sounded on approaching stations, passenger stops, portable or hand signals for reduced speed, whistle ("C") posts, cuttings, curves, tunnels, railway crossings, removable trolleys, removable repair derricks, track repair wagons, and other movable units; when approaching places of track work as previously notified in bulletins, independently of the absence of temporary signals; on receiving the hand signal "lower pantograph"; approaching groups of people or in other cases specified in instructions. Also, it is sounded when moving in times of mists, snowstorms and other unfavourable circumstances and worsening visibility, repeated occasionally.

The "vigilance" (бдителность) whistle signal consists of one short and one long sound. It is used approaching a block signal with a red light, on receiving a conditionally-permissive signal, and at a further movement into a block section; on passing a block signal with a red light, and also with an unintelligible or extinguished aspect, after a stop before the signal and further movement into the block section. It is also used at block and entrance signals displaying a lunar-white call-on signal, and all other cases of the arrival of a train in a station with a restricting aspect or extingished main lights in the entrance signal. It is sounded on the arrival of a train on an irregular track, in the absence of an entrance signal for this track. This signal must be sounded before further motion into the station throat.

Trains meeting on double track sound one long, the notification signal, while passing each end of the other train. In stations, the signalman or switchtender gives notice of the approach of trains by audible signals: one long sound for "odd" trains and two long sounds for "even" trains. Odd and even refer to the directions of trains (like "up" and "down"), and are specified at the particular station. Russia uses train numbers, like the United States, and even and odd numbers correspond to oppposite directions. On the Trans-Siberian, even is eastbound. The signalman or switchtender, hearing the whistle signal of a departing train, gives one long audible signal. The use of the whistle is restricted in designated locations of large population, near hospitals, and similar locations. Some signals are omitted, such as those for brake tests, while others are to be given softly. Vigilance and alarm signals are exempted from this restriction. Where whistle signals are not sounded by departing trains, some official provision is established for warning passengers.