GER Category 3 flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Absolute block

A signalling principle in which only one train may occupy a block section at a time. The section is released only after the preceding train has passed clear and the signal has been replaced to danger.

Line clear

The authority given by a signaller to allow a train to enter a block section. It must not be given until the preceding train is clear of the section and, where required, its tail lamp has been seen.

Trap point

A set of points that derails unauthorised movements to protect a running line. It normally stands in the derailing position and must be restored there after use.

Closed-loop communication

A safety communication method in which the receiver repeats the message back and the sender confirms it is correct, reducing the risk of misunderstanding in safety-critical instructions.

Double yellow aspect

A signal aspect warning that the next signal is at caution and the one beyond may be at danger. The driver must be prepared to stop at a subsequent signal.

Distant signal

A signal giving advance warning of the state of a stop signal ahead. At caution it means the next stop signal may be at danger; clear means the associated stop signals are clear.

Track circuit

An electrical circuit through the rails that detects a train by wheel-axle shunting. It can fail wrong-side, showing clear when the section is actually occupied.

Axle counter

A system that counts wheels entering and leaving a section to detect occupancy. A miscount can cause a wrong-side failure, so drivers must not rely on it alone.

Interlocking

A safety system that prevents conflicting routes from being set simultaneously. A signal cannot clear unless its route is locked and proved clear.

Ground signal

A disc or position-light signal authorising movement only within station limits or into an occupied section, at caution and prepared to stop short of any obstruction.

AWS warning

An audible warning in the cab followed by a brake demand if not acknowledged. The driver must apply the brakes immediately unless the system is already satisfied.

Gradient profile

The pattern of rising and falling grades along a route. Falling gradients lengthen stopping distance, so brake applications must be planned earlier on descending sections.

Temporary speed restriction

A speed limit issued by notice for engineering work or track condition. It must be acknowledged before departure and applies from the point stated in the notice.

Route knowledge

The driver's detailed familiarity with a route, covering signal positions, junctions, gradients, speed restrictions, crossings, tunnels, and station stopping points.

Stopping mark

A marked point on a platform where a specific train formation must stop. It ensures the train fits the platform and aligns with doors and dispatch equipment.

Braking distance formula

Stopping distance rises with the square of speed: doubling speed quadruples the distance needed for the same deceleration, before allowing for reaction time and adhesion.

Low adhesion

A condition caused by leaves, frost, dew, oil, or light rain after dry weather. It reduces grip and requires earlier, lighter brake applications and careful traction control.

Brake propagation

The time taken for a brake application to travel along the train. Rear vehicles apply later, so long trains need a longer allowance for brake build-up.

Dynamic brake

A regenerative or rheostatic brake that slows the train without friction. It reduces wear and heat on the friction brakes, which are kept for stopping and low-speed control.

Wheel slide protection

A system that releases brake force when wheels lock. A sustained slide damages wheels and must be reported and inspected for flat spots.

Brake continuity test

A test confirming the brake pipe is continuous and the brakes apply and release throughout the train. It is required after coupling or uncoupling vehicles.

Emergency protection

The procedure of placing detonators and exhibiting a red flag or hand signal in the direction of approaching trains after an unexpected stop, before reporting to the signaller.

Signal passed at danger

An event in which a train passes a signal showing danger. The driver must stop immediately, report to the signaller, and move only with explicit authority.

Train fire procedure

Stop where evacuation is possible, avoiding tunnels and viaducts if practicable, isolate traction power, evacuate passengers upwind, and request emergency services through the signaller.

Driver incapacitation

A situation in which the driver cannot control the train. The emergency brake is applied, the signaller is informed, and control passes only under defined authority.

Hot axle box

An overheated axle bearing detected by lineside equipment or inspection. The train must stop and be examined; it must not continue if derailment risk exists.

Phonetic alphabet

A standard set of spoken code words for letters, used with standard figure pronunciation to reduce errors in numbers and locations during safety-critical communication.

GSM-R emergency call

A radio call that takes priority over all other traffic. The signaller must be informed of any emergency call and the call must not be terminated prematurely.

Working timetable

The authoritative document giving scheduled times, speed restrictions, and route information. It is supplemented by weekly operating notices and special notices.

Defect report

A factual record of a fault or incident, completed before the end of the shift, stating observations, times, and locations rather than opinions.

Fitness for duty

The requirement that a driver be medically fit, rested, and free from impairing medication or substances before signing on. Tiredness must be declared before duty.

Just culture

A reporting environment in which errors can be reported without punitive action, except in cases of gross negligence or wilful violation, encouraging safety information to surface.