What is runway working?
Working on the most critical surface on the airfield: when it is closed, who clears entry and what must happen before it reopens.
The runway is where aircraft land and take off at high speed, so runway working is done only when the runway, or the relevant section, is closed or under arrangements specifically agreed with ATC and airport operations. The closure is decided and notified by the airport and ATC and shown by a closed marking (a cross, white on a runway) and unserviceability markers. Lights on a closed runway are normally off except as needed for the maintenance work (see Closed Runway Marking Lights). AGL staff wait at the holding position until they are cleared to enter, keep contact as the permit requires, and work only inside the agreed area.
The circuits to be isolated are agreed with ATC, because switching off runway lights changes what is available, and then isolated and proved dead by the electrical procedure. Runway lights run on high-voltage constant-current series circuits, so the regulator (CCR) is locked off and the circuit proved dead before anyone touches cable or fittings (see CCR Isolation and Electrical Isolation). A live series circuit must never be broken or left open-circuit, which is why isolation comes first. Everyone must be ready to vacate when instructed. Before reopening, all people, vehicles and tools are removed, the surface and edges are inspected for debris, the lighting is restored and checked, and ATC is told the area is clear. The runway is reopened only on their decision.
Frequently Asked Questions
Q1Can AGL work be done on a runway that is open?
Work on the runway itself is done only when the runway or the relevant section is closed, or under arrangements specifically agreed with air traffic control and airport operations. The closure is decided by the airport and ATC, and planned closures are notified in advance. AGL staff never decide a runway is closed on their own.
Q2How is a closed runway shown?
By a closed marking (a cross, white on a runway) and unserviceability markers at the closed area, by notification to pilots and by arranging the runway lighting as the airport procedure requires. Lights on a closed runway are normally off except as needed for the work. These are set by the airport and ATC, not by the working party.
Q3Why is contact with ATC kept while working on a runway?
ATC may need to change the plan, recall the working party or reopen the runway. Contact is kept by the method agreed in the permit, and everyone vacates the runway promptly when instructed.
Q4How does electrical isolation fit with runway working?
Isolating a runway lighting circuit changes which lights are available, so the circuits are agreed with ATC and airport operations as well as being made safe electrically. Runway lights run on high-voltage series circuits, so the regulator is locked off and the circuit proved dead before anyone touches cable or fittings. The isolation, lock-out and proving dead steps are those of the airport procedure.
Q5What must be checked before a runway is reopened?
All people, vehicles, tools and materials are removed, the runway and its edges are inspected for debris, the lighting is restored and checked as the procedure requires, and ATC or airport operations are told the area is clear. The runway is reopened only on their decision.
Q6Why is a vehicle or person on a runway such a high risk?
Aircraft land and take off at high speed on the runway and cannot stop or steer around an obstruction. A person or vehicle on the runway at the wrong time can lead to a runway incursion, which is why entry needs clearance and the runway status must be certain.
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