What is emergency control?
How airfield lighting stays under control, or is made safe, when the normal control or power is lost — and how to hand back to normal with the status verified.
Emergency control is the set of provisions that keep airfield lighting controlled, or made safe, when normal operation is lost or an emergency occurs. There are four common parts: backup control (another control position, or local control at the CCR), secondary power (a generator or battery system that takes the essential load if the main supply fails), preset settings (a lighting configuration agreed in advance for an emergency) and emergency off (removing the energy from a hazard, such as a damaged cable). Which exist depends on the design and the airport’s procedures.
Two points keep it clear. First, losing the screen is not losing the lights: the CCRs drive the lights, so a failed control system or link can leave them on, and the status becomes unknown (see ALCMS Failure Flow). Second, a fallback only works if it has been tested. A switch that sticks, a weak battery or an out-of-date procedure shows up in the emergency, so the fallback paths are exercised regularly and the staff are trained. When normal control returns, recovery ends with verified status: confirm the equipment is back in remote mode and reporting, and that the lights match what the controller expects. People working on the equipment are protected by physical isolation, not by an emergency setting.
- Recognise. Identify what has been lost: control, monitoring, power, or the airfield itself.
- Confirm. Establish the real state of the lights by observation or another route.
- Fall back. Use the backup control, secondary power or preset, under procedure.
- Log. Record what was done, by whom, and when.
- Recover. Return to normal control and verify the status before standing down.
Emergency Control Explorer
Pick a situation
The situation AND THE FALLBACK
What to do AND NOT DO
Teaching simulation. Responses are illustrative; the real actions are set by the airport’s emergency and operating procedures.
Frequently Asked Questions
Q1What is emergency control?
The provisions that keep airfield lighting under control, or make it safe, when normal operation is lost or an emergency occurs. They typically include backup control positions, secondary power, preset lighting configurations and an emergency off for a hazard.
Q2What happens if the ALCMS fails?
The lights are normally controlled from another position or at the CCRs, for example by local control at the equipment or from a backup panel, so lighting can continue. Which fallbacks exist depends on the design, which is why they are tested and the staff are trained to use them.
Q3What is secondary power for?
To keep the essential lighting running if the main supply fails. A generator or battery system takes over, and the standards set how quickly the switch-over must happen for different runway types. The control and monitoring system should be supported too, so the operators still see the state of the field.
Q4Is losing the control screen the same as losing the lights?
No. The lights are driven by the CCRs, so if only the screen or the link is lost the lights can stay on, as they were. The status on the screen is then unknown, so the real state should be confirmed by other means, such as observation, until monitoring is restored.
Q5Who carries out emergency control actions?
Authorised staff, under the airport's emergency and operating procedures, from the control position in charge. Actions are logged. Anyone working on the equipment must also be protected by physical isolation and lock-off, not by an emergency setting.
Q6Why must fallbacks be tested?
A backup that has never been used may not work when it is needed: a switch may be stuck, a battery weak, or a procedure out of date. Regular tests of the fallback paths, and drills for the staff, show the problems while there is time to fix them.
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