Signalling Flashcards
1
Q
What is the main principle of Absolute Block Signalling?
A
Ensuring that there is only ever one train in one section at any one time. This is to keep trains apart and prevent collisions.
2
Q
What are the limitations of absolute block signalling?
A
Long sections covered by absolute block which can make it difficult to increase capacity on these lines.
3
Q
What type of signals are relied upon within absolute block signalling?
A
Semaphore signals mainly but colour light aspects can also be used in sections of intermediate block signalling.
4
Q
How can you identify that a semaphore signal applies to you?
A
It should be red and white or yellow and black when facing the signal (not black and white as this is the colour of the back of the signal and will apply to trains on the opposite line). Signals that apply to you should also be pointing left with the signal post on the right.
5
Q
What is meant by a red and white semaphore signal that is in the horizontal position or featuring a red light at night?
A
Signal at danger/ stop.
6
Q
What is meant by a red and white semaphore signal that is tilted at 45 degrees and features a green light at night?
A
Proceed.
7
Q
Which signals within absolute block signaling will you also receive an AWS signal with?
A
Just distant signals, not stop signals. You will receive AWS warnings for both distant and stop signals within an intermediate block section.
8
Q
How far in advance of a distant signal will you receive an AWS warning?
A
180 metres before the distant signal.
9
Q
What is the purpose of a backing plate behind a semaphore signal?
A
To make the signal clearer.
10
Q
What are distant signals?
A
Signals that cannot show a stop/danger aspect or indication.
11
Q
What is meant by a black and yellow semaphore signal that has the arm in the horizontal position and features a yellow night at light?
A
Proceed at caution. Be prepared to stop at the next stop signal or other specified place to which the distant signal applies. Any associated stop signals that are controlled by the same signal box will be displaying a danger aspect.
12
Q
What is meant by a black and yellow semaphore signal where the arm is raised or lowered 45 degrees and a green light is displayed at night?
A
All associated stop signals worked by the same signal box will be clear (displaying a proceed aspect).
13
Q
How far from stop signals are distant signals placed?
A
Within service braking distance.
14
Q
What is service braking distance?
A
This is calculated based on line speed and the worst performing train’s braking ability.
15
Q
What should your actions be as a driver who has received a cautionary distant signal but upon approaching the stop signal the danger aspect changes to a proceed aspect?
A
You may proceed past this signal but you must be prepared to stop at the next stop signal that is controlled by the same signal box.
16
Q
In an area that a signal box controls, what is the name of the first signal?
A
The home signal.
17
Q
In an area that a signaller controls, what is the final signal before leaving that area called?
A
The Section Signal.
18
Q
What is the section between the home signal and the section signal referred to as?
A
Station limits.
19
Q
Can stations be included within a signaller’s station limits?
A
Yes but they don’t have to contain a station.
20
Q
What is the area between Signal Box A’s Section Signal and Signal Box B’s Home Signal called?
A
The Absolute Block Section.
21
Q
Who needs to give permission for a train to move into the Absolute Block Section and why?
A
Signal Box A must seek the permission of Signal Box B for a train to move into the Absolute Block Section. Whilst Signal box B doesn’t control the Absolute Block Section, they will be able to visually see whether the train in front has left the absolute block section and passed the clearance point.
22
Q
When a train passes the home signal, what is the signaller looking to determine? How does he do this?
A
Whether the train is fully within his station limits. He does by looking for taillights once the train has passed the Clearance Point.
23
Q
What is the clearance point?
A
400m or 1/4 of a mile past the home signal.
24
Q
Why does the signaller look for taillights?
A
To see that the train has fully left the section prior to his station limits. If there are no visible taillights, the train could have separated and part of it could be in the previous section.
25
How might the clearance point be used to prevent SPADs?
When a train is approaching the home signal, there may already be a train within that signaller’s station limits. The signaller can use the clearance point to determine that the train in front is definitely out of the way, in the event that the train behind passes the home signal at danger. This prevents collision.
26
When a signaller only has one stop signal within his station limits, is this considered to be the home signal or the section signal?
It is considered to be both.
27
Where there is only one stop signal within a signaller’s station limits that is considered to be both the home and the section signal, what would you expect to see before it?
A distant signal with AWS magnet to tell you whether this stop signal is displaying a danger or a proceed aspect.
28
If a danger aspect is initially showing on a single stop signal that then changes to a proceed aspect what does this tell you in terms of the signal itself and what are your actions as the driver?
When the single stop signal is initially showing a danger aspect, it is considered to be the home signal and you must stop at this. When this changes to a proceed aspect, the stop signal then becomes the section signal and you may pass the signal to leave that signaller’s station limits and enter the absolute block section.
29
What does it mean if a distant signal is on the same post as a stop signal?
The stop signal is worked by the signal box at that location and the distant signal is worked by the signal box ahead.
30
Why might a distant signal that applies to a stop signal ahead be located on the same post as the previous stop signal?
Because there is no service braking distance for the next stop signal so this is the only suitable location for the distant signal.
31
What does it mean if the stop signal is at danger (horizontal) and the distant signal is at caution (horizontal) on the same post?
You must obey the most restrictive aspect and stop at this signal. The stop signal ahead (and any associated signals) will also be showing a danger aspect.
32
What does it mean if the stop signal is at proceed (45 degrees) and the distant signal is at caution (horizontal) on the same post?
You may proceed past this signal but the stop signal ahead (and all associated signals) will be showing a danger aspect.
33
What does it mean if the stop signal is at proceed (45 degrees) and the distant signal is also at proceed (45 degrees) on the same post?
You may proceed past this signal and the stop signal ahead (and any associated signals) will be showing a proceed aspect.
34
What does a white diamond denote on a signal post?
That area is track circuited and the signaller knows of your presence even though he cannot see you from his signal box.
35
How long must you wait before contacting the signaller when stopped at a signal post displaying a white diamond?
Up to 10 minutes.
36
Where there are a number of junctions in and out of a signaller's station limits, how many home signals can there be and how many section signals can there be?
There is no limit to the number of home sections that can exist within a signaller's station limits but there can only be one section signal in the direction of travel to signify the end of the station limits (one per line if two or more running lines).
37
Explain how the home signals would work to allow one train from a running line into a station within the signaller's station limits whilst holding another train, joining from a junction, outside of the station?
The home signal on the main line would allow a train into the station. A separate home signal would then hold another train joining from a junction and prevent them from coming into the station as there is already a train within that section (one train in one section at one time).
38
What is the definition of an Intermediate Block Section?
The area from the section signal in rear until the intermediate block home ahead (where there is one intermediate block section) or the area from the intermediate block home in rear until the intermediate block home ahead (where there is more than one intermediate block section).
39
What is the purpose of Intermediate Block Sections?
As some areas of absolute block can be particularly lengthy, intermediate block sections allow for these to be shortened to allow more trains over this portion of line but whilst adhering to the principle of 'one train in one section at one time'. This allows for greater capacity on these lines.
40
How are Intermediate Block Sections controlled?
These sections are track circuited and are controlled by the previous signal box.
41
What type of signals exist within intermediate block sections?
Colour light signals.
42
Do intermediate block signals and any associated distant signals contain AWS magnets and would you receive any cab warnings for these?
Yes, both intermediate block home signals and associated distant signals will contain AWS magnets unlike signals within normal absolute block signalling where only the distant signals are fitted with AWS. As such, you will receive cab warnings for both intermediate block home signals and associated distant signals.
43
For any type of distant signal, how far in advance of the signal would the AWS magnet be located?
180 metres
44
Describe the signal post sign that denotes a signal is an intermediate block signal?
White background with black vertical line.
45
What signal post sign would be located on a distant signal within an intermediate block section?
A triangle symbol or the letter 'R' to denote that it is a distant signal.
46
Where an intermediate block section exists, what does this change the definition of an absolute block section to?
The section between the intermediate block home in rear to the home signal ahead.
47
What is a semaphore subsidiary signal?
Semaphore subsidiary signals are always associated with the main arm of the semaphore stop signal and will always be located below the main arm on the same post.
48
What is meant when the subsidiary arm is in the horizontal position or a red, white or no light is showing?
Obey the main arm.
49
What is meant when the subsidiary arm is at 45 degrees or a green light is shown?
This should be read as a proceed aspect and authorises the driver to pass the main arm at danger and proceed at caution towards the next train, signal or buffer stop and to be prepared to stop short of any obstruction.
50
What is meant by a subsidiary arm that is displaying the letter C?
Calling On. This authorises the driver to pass the main arm at danger and proceed at caution towards the next train, signal or buffer stop and be prepared to stop short of any obstruction (likely to mean that you are calling at a station where a train is already at a stand and you will be entering permissively).
51
What is meant by a subsidiary arm that is displaying the letter S?
Shunt Ahead. This authorises the driver to pass the main arm at danger and proceed at caution for shunting purposes only.
52
What does a miniature arm offset from the main signal tell you?
This is a shunting signal and not a subsidiary arm.
53
What is permissive working and give an example of where this might be done on a day-to-day basis?
Where more than one train is allowed into a section at any one time. Pulling into a station where a train is already at a stand is an example of permissive working.
54
Name the three ways in which routing can be done with semaphore signals?
Stepped, stacked and route indicator
55
What is stepped routing in semaphore signalled areas?
The highest step denotes the highest speed route. The lowest step denotes the lowest speed route. If two steps are the same height, these individual routes will share the same speed. The signals will also be ordered from left to right to help drivers identify which route is theirs (the first signal on the left will apply to the furthest left route).
56
What is stacked routing in semaphore signalled areas?
Displays signals from top to bottom on the signal post and this corresponds the running lines from left to right (the top signal applies to the furthest left route).
57
How is a route indicator used to route trains in semaphore signalled areas?
A figure or letter will be shown on the signal itself which will contain a semaphore arm to show which route the movement is being signalled onto. When the signal is at danger, the route indicator will be unlit. When the signal is cleared, the route indicator will illuminate.
58
What are your actions as a driver if the route indicator becomes lit but the signal arm remains at danger?
You do not have authority to proceed. You must wait for the signal arm to clear. The signal arm should ways be your indication to proceed, not the route indicator.
59
What does an illuminated route indicator tell you about the points for the route you are about to take?
These are all set correctly.
60
If the semaphore arm clears but you do not receive an illuminated route indicator, what are your actions and why?
Do not proceed and contact the signaller. The points for your route may not be set.
61
What is a non-block signal?
Non-block signals aren't used for the usual purpose of signals within absolute block signalling to keep trains apart or control movements and aren't constricted to absolute block rules (one train, one section, one time). However, non-block signals could be in place to protect something else such as a level crossing.
62
Who would normally control a level crossing that falls within a signal box's station limits?
Could be controlled by that signal box but is more likely controlled by a separate crossing keeper.
63
What might you expect to see if a non-block signal fails at a level crossing, where this signal purely protects the level crossing, and what would your actions be as a driver?
You may receive a green hand signal (green flag is waved) from the Crossing Keeper to tell you that the crossing is clear.
64
Where can drivers find the locations where a green hand signal/flag may be shown in the event of a non-block signal failure?
The Sectional Appendix.
65
What are your actions if you receive a green flag at a level crossing that is not listed in the Sectional Appendix as an area where a green flag can be shown in the event of a non-block signal failure and where that signal is a normal block signal?
You must ensure that you have a proceed aspect on the applicable signal before proceeding over the signal as the green hand signal does not replace the normal block signal that falls before the level crossing. If you pass a signal due to receiving a green flag when the signal itself is not clear, this would be considered as a SPAD.
66
When the railway is updated, how might a semaphore distant signal be replaced?
With a 2 aspect colour light head that can show either a green or yellow aspect. The signal ID plate would still contain a triangle or the letter 'R' to denote that it is a distant signal.
67
When the railway is updated, how might a semaphore stop signal be replaced?
With a 2 aspect colour light head that can show either a red or green aspect. These can still be either a home or a section signal.
68
Is it possible for absolute block signalled areas to contain colour light signals and semaphore signals?
Yes.
69
Where there are colour light signals in an absolute block signalled area, does this mean that the section is track circuited?
No.
70
Do colour light stop signals receive AWS warnings?
No, you would only receive AWS warnings for distant signals irrespective of whether they are semaphore or colour light. The only time you would get AWS warnings for both stop and distant signals is in an intermediate block section.
71
What is the normal position for a semaphore stop signal and why?
The normal position for a semaphore stop signal is always horizontal/danger until it is cleared. If this signal fails, it will always fail safe in the horizontal position.
72
How can distant signals be cleared?
Distant signals cannot clear until all associated stop signals are cleared. This means that if all the stop signals are at danger, the distant cannot clear until all stop signals have changed to a proceed aspect. Therefore, the distant will always be the last to clear.
73
If you are acting permissively and you are signalled to 'call on' and expect to see another train but do not, and the signal ahead is displaying a proceed aspect. What must your actions be as a driver?
Do not assume that the proceed aspect is for you. The train that you were going to be acting permissively with has most likely already left and the signal was for them but this signal has not cleared yet. You must wait for the signal to display a danger aspect and then wait for it to clear again before proceeding.
74
What are your actions if you are unable to determine whether a signal is at danger or proceed?
Treat the signal as if it is showing its most restrictive signal and then contact the signaller for confirmation.
75
If a distant signal is at 45 degrees and is showing a proceed aspect but you still receive an AWS warning what are your actions?
You must treat the signal as being at caution as it may not have had time to reset.
76
In what two circumstances do you not need to treat the distant signal as being at caution when you receive an AWS warning?
Where the signal changes to clear after your train has passed over the AWS magnet or where a warning board or emergency indicator is positioned at the signal (AWS warning is for this and not to denote a cautionary aspect on the distant signal).
77
What are the two purposes of track circuits?
To tell the signaller where you are located and to operate the signals in areas of track circuit block
78
What is used to separate sections in areas of track circuit block?
Insulated Block Joints (IBJs)
79
What are Insulated Block Joints and is there a set distance for these to exist after a signal?
These are placed after signals to set the previous signal to danger when a train has passed. There is no set distance for an IBJ to exist after a signal.
80
If track circuits fail, what will happen to the associated signals?
They will always fail safe and display a danger aspect or the most restrictive aspect available.
81
What is an overlap section?
A portion of line after a signal that must be clear or unoccupied before the next signal in rear can clear.
82
How do overlap sections and Insulated Block Joints work together?
The overlap works in conjunction with the Insulated Block Joint to ensure that a train is safely past a signal and fully within that section before changing the previous signal to the appropriate aspect.
83
How is the length of the overlap determined?
This depends on the number of aspects used within the signalling sequence in that location.
84
What is the length of the overlap section for 4 aspect signalling?
Overlap of 200yds
85
What is the length of the overlap section for 3 aspect signalling?
Overlap of 300yds
86
What is the length of the overlap for 2 aspect signalling?
Overlap of 400yds
87
What aspects can be shown in a 4 aspect signalling sequence?
Red, single yellow, double yellow, green
88
What will 4 aspect signalling make use of to control the signal aspects when trains cross into different sections?
Insulated block joints and an overlap of 200yds.
89
When a train passes a green proceed aspect and crosses both the insulated block joint and the overlap of 200yds, what will that aspect change to for following trains?
A red danger aspect
90
At what point will that initial aspect display a green proceed aspect again?
Once the train has safely passed the IBJ and overlap of the next four signals as that initial signal will change through the 4 aspect signalling sequence until it displays a green again (after showing red, single yellow and double yellow).
91
When four aspect signal heads are modernised, what will they be replaced with?
2 aspect LED heads that are capable of showing a 4 aspect signalling sequence (not the same as 2 aspect signal heads that are only capable of showing a 2 aspect sequence).
92
Where a signal is controlled by the signaller and it is the signaller who sets and clears the aspects, what are these called and what would the signal ID plate look like?
Controlled Signals. The ID plate would be black backed and would contain the usual signal ID number.
93
What is the default position of controlled signals?
Red danger aspect until these are cleared by the signaller.
94
Where would you expect to see controlled signals?
In high-risk areas such as junctions or stations.
95
How would you identify an automatic signal from the signal post itself?
There would be a sign above the usual ID plate that is white backed with a black horizontal line through it to denote an automatic signal.
96
How do automatic signals work?
Set and cleared by the passage of trains.
97
Can the signaller control an automatic signal?
No, the signaller cannot set or clear an automatic signal.
98
Where would you expect to see automatic signals?
In low risk locations such as straight portions of track.
99
What is the default position of automatic signals?
Automatic signals will always try to show green or the least restrictive aspect.
100
Name 3 types of signal post indicators?
Junction indicator, associated position light, route indicator
101
What else might you expect to see on a signal post?
A Signal Post Telephone (SPT) with or without a Limited Clearance Sign, a Signal Post ID plate (with or without an arrow pointing to the line that the signal applies to), shades above the coloured aspects for clarity in different weather conditions, hot strips or eyebrows to deepen the colour on specific aspects and to signify which line the aspect applies to.
102
In 4 aspect signalling, what does a green proceed aspect tell you?
You can proceed past this signal and the next signal will be a proceed aspect (either a green or a double yellow).
103
In 4 aspect signalling, what is a double yellow aspect known as and what does this tell you?
Preliminary caution. You can proceed past this signal but be prepared for the next signal to show a single yellow.
104
In 4 aspect signalling, what is a single yellow aspect known as and what does this tell you?
Caution. You can proceed past this signal but be prepared to stop at the next signal as this will be displaying a red danger aspect.
105
In 4 aspect signalling, what is the red aspect known as and what does this tell you?
Danger. You must stop at this signal.
106
Where would 4 aspect signalling be most commonly found?
High speed lines such as the East Coast Mainline.
107
What is the signal section in 4 aspect signalling?
Signal to signal.
108
In 3 aspect signalling, what is the signalling sequence?
Red, single yellow, green
109
Where would you usually expect to see 3 aspect signalling?
Lower speed lines than those where 4 aspect signalling is used.
110
In the absence of a double yellow aspect in 3 aspect signalling, what should the presence of a single yellow aspect tell you?
That you must be prepared to stop at the next signal as this will be set to red/danger.
111
When 3-aspect heads are modernised, what will they be replaced with?
They are often replaced by single aspect LED heads which are capable of showing a 3-aspect signalling sequence.
112
Where would you usually expect to see 2 aspect signalling?
On lower speed lines.
113
What type of signals are used in 2 aspect signalling?
Stop signals and distant signals
114
What aspects can be shown on a stop signal?
Red or Green
115
What aspects can be shown on a distant signal?
Yellow or Green
116
What is the difference between 2 aspect signals that are used in absolute block sections and those used in track circuit block?
In absolute block, there will be a distant signal followed by a home and a section signal that are both stop signals. In track circuit block, the distant signal will alternate with a stop signal and these won't be considered to be the home or the section signals. In track circuit block, all 2 aspect signals will have AWS magnets located 180m before them but absolute block signals only have AWS magnets before distant signals (unless in an intermediate block section).
117
When will a green distant signal change to yellow in track circuit block signalled areas?
When the train has passed the IBJ and overlap of the next section once it has passed the following stop signal as the signal section is stop signal to stop signal. There won't be an IBJ or overlap after a distant signal.
118
What would you expect to see on a signal ID plate for a distant signal?
A triangle or the letter 'R'.
119
What is an outer distant signal?
On higher speed lines, you may need extra notice ahead of a signal and both outer distant and distant signals may be used to do this.
120
What would you expect to see on a signal ID plate for an outer distant signal?
The letters 'RR'.
121
Where there are outer distant and distant signals, what would you expect to happen with the signalling sequence?
The outer distant would need to show a 4 aspect signalling sequence to be able to show you a double yellow and then the distant would then alternate to 2 aspect signalling to show you a single yellow that would then bring you to a 2 aspect stop signal that could show you a red (this is because a 2 aspect sequence could not show a double yellow to denote an outer distant signal- both 2 and 4 aspect signalling sequences could be shown on a 2 aspect head).
122
Where might you see a single aspect yellow that can never be cleared?
In some locations there may be a single aspect red that can never be cleared to protect a gate, crossing gate or buffer stop where trains can never pass. To fit in with the signalling sequence, there would need to be a single yellow before the red, so therefore there can be single yellows that will never clear.
123
When transitioning from a 3-aspect signalling sequence to a 2-aspect signalling sequence and your last signal in the 3-aspect area is green, what must the next stop signal be when you move into the 2-aspect area and why?
The 2-aspect sequence stop signal must show a green. This is because 2 aspect stop signals can only show a red or a green and having a green signal before would not fit into the correct signalling sequence as a green can never bring you to a red. There would need to be a 2 aspect distant signal displaying a single yellow before you could be brought to a red stop signal.
124
When transitioning from a 3-aspect signalling sequence to a 2-aspect signalling sequence and your last signal in the 3-aspect area is yellow, what could the next stop signal be when you move into the 2-aspect area and why?
It could be either a green or a red but you must be prepared for a red.
125
When moving from 3-aspect signalling to 4-aspect signalling and you receive a green aspect in the 3-aspect section, what could your next signal in the 4-aspect section show you and why?
A single yellow despite 4-aspect signalling being able to show you a double yellow. This is because a double yellow would not fit into the signalling sequence.
126
What is the risk with moving from 4-aspect signalling to 3-aspect signalling when you receive a green aspect in the 4-aspect area before moving into 3-aspect?
Double yellows are removed in 3-aspect signalling so you may go straight from a green into a single yellow which may mean that you forget where you are and approach the signal too quickly due to anticipating a double yellow.
127
What are junction indicators used for?
To indicate to the driver which route he will be taking in areas where there are various junctions or routes.
128
What type of signal will junction indicators be found on and why?
Controlled signals so that the signaller can ensure that the correct routing is given to each train.
129
Will junction indicators ever be found on an automatic signal?
No.
130
How many junction routes can be shown on a junction indicator?
6 junction routes via 6 separate arms that contain 5 lights per arm.
131
Where would a junction indicator be found on a signal post?
Above the main aspect and these work in conjunction with the main aspect.
132
When would you expect to see a junction indicator lit?
When a proceed aspect is showing on the main signal, a line of white lights will be shown to indicate which route is to be taken and whether this is to the left or the right of the straight route.
133
What does a junction indicator tell you about the junction itself?
Whether this is to the left or the right of the straight route.
134
If there is an obvious straight route and a junction to the left of this, which routes would you expect to see a junction indicator for and why?
You would see a junction indicator for the junction to the left but not for the straight route. This is because there is normally no junction indicator provided for an obvious straight route, so if you do not receive a junction indicator, you know that you will be taking the straight route.
135
If there is no obvious straight route and two junctions fork off, which junction will you see a junction indicator for?
Both junctions will have junction indicators that can be lit depending on the route that you are taking (a junction indicator will be provided for all signalled routes).
136
If the straight route is not the highest speed route, will the junction indicator apply to the straight route or the junction?
The junction indicator will normally apply to the lower speed route which, in this case, is the straight route.
137
If there are diverging routes of equal speed, which route would you receive a junction indicator for?
A junction indicator will be provided for each route and the route indicator that corresponds with the route you will be taking will be illuminated whilst the other remains unlit.
138
How are junction indicators read?
Top to bottom. The bottom indicator will always apply to the route furthest left or right of the straight route.
139
If the junction indicator illuminates first and the main aspect is still showing a danger aspect, what are your actions?
Do not proceed until you receive a lit junction indicator and a proceed aspect. The proceed aspect is your authority to proceed, not the lit junction indicator.
140
Where might a route indicator be used instead of a junction indicator?
Where there are more than 6 possible routes.
141
What is a route indicator?
A display that is located on the signal itself which will display either a letter or a number that corresponds with the route that you will be taking.
142
What do numbers usually correspond with on a route indicator?
Platform numbers
143
What do letters usually correspond with on a route indicator?
A route that you will be taking when leaving a station (eg: M for Mainline).
144
How might a main aspect and route indicator be used to help you when pulling into a platform that has intermediate platform stops such as platform 7a, 7b and 7c?
The route indicator will display a 7 and the colour of the signal will tell you which intermediate platform you are stopping on. If you receive a yellow aspect on approaching the station, you know that your next signal will be red so therefore know that you will be stopping at 7a. If you see a green aspect on approaching the station, you know that you will be stopping on 7b or 7c and the next signal will either be a green or yellow aspect. You will stop wherever the aspect is showing red.
145
Can route indicators also be associated with a junction indicator or associated position light?
Yes.
146
How will the signalling system work to slow you when you have been travelling on a high speed line and you are about to take a lower speed junction?
You are likely to receive yellow and red signals before a junction, even if the junction is clear. The final signal before the junction often won't clear until you have been in that section for a specified amount of time that would have allowed you to slow to a suitable speed to join the lower speed line after the junction.
147
Where might you see flashing yellow signals and what is their purpose?
When taking a junction where the speed of the junction does not differ significantly from that of the main line. The flashing yellow lights inform the driver that the route is set correctly for them to take the lower speed junction.
148
What might it mean if the yellow lights are not flashing when you expect them to be?
The route has not been set correctly or a train might still be in the section that you are about to join. This might mean that you will be brought to the junction at danger before you can proceed.
149
What is the signalling sequence for flashing yellows?
Green, flashing double yellows, flashing single yellow, steady single yellow, red (after junction).
150
If the double yellows approaching the junction are steady and not flashing when you would normally expect them to be flashing, what would this tell you and what would your actions be?
The route has not been set for the junction. Proceed to the next single yellow. If this is also steady and not flashing, you will need to contact the signaller once you reach the danger signal to let him know that the route does not appear to be set. Or wait for the danger aspect to clear and see whether the junction indicator on this final signal (the one that would usually be steady yellow) is set correctly. If it isn't set correctly, then contact the signaller to query this.
151
What would it mean if two flashing yellows are followed by a single solid yellow aspect?
The route is no longer set and you will be brought to the junction at danger.
152
What are Class 1 trains?
Express passenger trains
153
What are Class 2 trains?
Ordinary Passenger Trains (stopping services)
154
What are Class 3 trains?
Empty Coaching Stock if specially advised
155
What are Class 5 trains?
Empty coaching stock trains
156
What classes of train can Northern trains act permissively with?
1, 2, 3, 5 and 0 (light locomotives)
157
Why must you only work permissively where authorised to do so?
Only some tracks have signals that permit permissive working so permissive working can only be authorised by the signaller.
158
Where can you find out whether you are authorised to work permissively at a certain location?
The Sectional Appendix?
159
When working permissively, what objects should you be looking for and how should you approach?
Proceed at caution towards buffer stops, obstructions, trains or signals and be prepared to stop 6ft 6in short of these.
160
When you are operating a passenger service, where will the signals always be set to?
Your final location (could be a platform within a station).
161
How would you know if you are being signalled to your final location when operating a passenger service?
There will be a main aspect set to danger and an associated position light with two white lights at 45 degrees which means that you have permission to move into a permissive platform.
162
When operating an empty coaching stock, where will your signals be set to?
To the next signal- you will travel signal to signal and therefore may be held at signals as you are lower in priority compared to passenger trains.
163
Why is it important to ask the signaller what you are going to be acting permissively with?
You must ensure that you are allowed to work permissively with the classification of train that is already in that section. This is particularly important when working in an area where you would not usually work permissively.
164
Can passenger trains enter goods loops?
Passenger trains must not enter goods loops unless the signaller gives permission to do so and you are permitted to work permissively with any trains already in that section.
165
Can Empty Coaching Stock trains enter goods loops?
Yes.
166
If you are joining a goods loop via a main aspect displaying a yellow followed by a red aspect, will you be working permissively?
No, you will know that there are no other trains in the loop.
167
How would you know if you were going to be working permissively when joining a goods loop?
You would see the main aspect at danger and a position light containing two white lights at 45 degrees.
168
If you saw that you were going to be working permissively when joining a goods loop, what would your actions be?
Call the signaller before proceeding to ask what you will be working permissively with. As working in a goods loop, there is a high chance that freight trains will be in there which cannot be worked with permissively unless operating as empty coaching stock.
169
Can you ever leave a station under the authority of a position light?
No, you must only leave the station under the authority of the main aspect unless you have the permission of the signaller to leave under a position light.
170
Can you ever leave a station under the authority of a position light when shunting? If so, why is this?
Yes because when shunting you expect to be moving signal to signal.
171
When an associated position light is unlit, what does this mean?
Obey the main aspect
172
When an associated position light shows two white lights at 45 degrees, what does this mean?
The driver is authorised to proceed at caution towards the next buffer stop, obstruction, train or signal and be prepared to stop short of any obstruction even if the main aspect is showing a danger aspect.
173
Where are position lights that are not associated to a main aspect most commonly seen?
On the ground to control shunting movements around depots or stations or main to main cross overs on the mainline.
174
What is meant by a position light showing two horizontal red lights?
Stop/Danger
175
What is meant by a position light showing one red light and one white light horizontally?
Stop/Danger
176
What is meant by a position light showing two white lights at 45 degrees?
Proceed at caution as far as line can be seen to be clear but do not pass any other signal at danger and be prepared to stop at buffers, obstructions, trains or signals.
177
When a position light displays yellow aspects, who do these apply to?
These are shunting stop signals and apply to trains wishing to join the main line.
178
If you are shunting or wanting to go into the shunt neck, what are your actions upon seeing yellow position lights?
You may pass these signals without them being cleared.
179
If you are not shunting and see a yellow position light, what are your actions?
You must stop at these signals.
180
What does a position light with two horizontal yellow lights mean?
The movement is only permitted if shunting. If going onto a main line, this means stop/danger.
181
What does a position light with one yellow light and one white light horizontally mean?
Movement only permitted if shunting. If going onto a main line, this means stop/danger.
182
What does a position light with two white lights at 45 degrees mean where it is normally capable of showing yellow position lights?
Proceed at caution, if you are joining the main line, as far as the line can be seen to be clear but do not pass any other signal at danger. Be prepared to stop at buffers, obstructions, trains or signals. This does not apply to you if you are shunting.
183
How would you know if a colour light signal is not in use?
It will be covered by a black bag with a white cross on it.
