What is the visual inspection sequence?
The order in which airfield lighting is checked by eye — prepare, view the lit pattern, walk the lights, check the surroundings, look closer once isolated, then classify and record every defect.
Visual inspection is checking the lighting system by eye to find defects before they cause a failure. The sequence runs from far to near: the lit pattern is judged from a distance, each fixture and sign is then examined on foot, the surroundings are checked, and only after isolation (and earthing where the site procedure requires it) are connectors, seals and cable entries looked at closely.
Looking is not measuring. A visual inspection finds damage, dirt, misalignment, loose parts and signs of water or heat, but it cannot show insulation condition, continuity or light output. It tells you where to test. Covers and enclosures are opened only when the circuit is isolated, locked out and proved dead, under the airport’s permit-to-work.
- Prepare. Obtain the permit, review earlier defect records, agree access with airport operations and take the right PPE and radio.
- Lit view. With the circuit on and, for light output, after dark, judge the pattern from a distance for lamps out, dim or uneven lights, wrong colour and gaps.
- Walk. Examine each fixture and sign for cracks, dirt, tilt, loose or missing fasteners and damage to frangible parts.
- Surroundings. Check pavement and sealant, pit and handhole covers, standing water, debris and vegetation growth.
- Close look. Once isolated and proved dead, inspect connectors, gaskets, cable entries and internals for corrosion, damp and heat marks, then refit covers and seals before the circuit is restored.
- Record. Classify each defect, photograph where permitted, log it and raise corrective work orders.
Frequently Asked Questions
Q1What is the visual inspection sequence in airfield ground lighting?
It is the order in which an airfield lighting system is inspected by eye: prepare and obtain a permit, view the lit pattern from a distance, walk the fixtures and signs, check the surroundings, look closer at components once the circuit is isolated, then classify, record and report each defect.
Q2Why view the lit pattern before walking up to the lights?
Patterns, gaps, uneven brightness and wrong colours are easiest to judge from the pilot's or driver's viewpoint and from a distance. Close up, a single fixture looks fine while the row as a whole looks wrong. The lit view finds what to examine; the walk-round confirms the cause.
Q3Can a visual inspection replace testing?
No. Looking finds visible damage, dirt, misalignment, loose parts and signs of water or heat. It cannot show insulation condition, continuity or photometric output. A visual inspection tells you where to test, and the tests tell you how serious the problem is.
Q4When can covers and enclosures be opened?
Only after the circuit is isolated, locked out, proved dead and, where the site procedure requires it, earthed, under the airport's permit-to-work. Series circuits can carry hazardous current, so close inspection of connectors, cable entries and transformers is never done on a live circuit.
Q5What should be recorded for each defect?
Location or fixture identifier, what was seen, its likely severity, a photograph where permitted and the date and inspector. Consistent records let defects be tracked and trended, and they feed corrective work orders and the next preventive plan.
Q6How often should visual inspections be done?
Frequency is set by the airport's maintenance programme, the regulator and the equipment manufacturers' instructions. Quick lit checks are generally done often, and detailed close-up inspections less often, usually combined with scheduled preventive maintenance.
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