What is defect classification?
Sorting every defect by what it does — to safety, to function and to performance — so a chipped edge and a cracked lens are never treated the same.
Defect classification sorts each defect found at inspection into a class by its effect: on safety, on whether the asset still works, on whether it still performs within limits, and on whether it is getting worse.
The class is decided by what the defect does, not by how it looks. In the example scheme, a defect with no effect on safety or function is minor and is recorded and monitored. A defect that reduces function or performance is major, so repair is planned and the asset re-checked. A defect that is a safety hazard or removes a required function is critical: it is reported and made safe first, because aircraft and vehicles depend on the lighting being right.
The class of one defect, such as minor, major or critical. It sets the response and its priority.
One overall grade for the whole asset, taken from the worst of its classified defects. It drives planning and trending.
- Record the defect as found. Asset, location, a description and a dated photograph, before anything is cleaned or adjusted.
- Ask about safety. Could it harm aircraft, vehicles or people, or leave a hazard on a movement area?
- Ask about function. Does the asset still do the job it is there for?
- Ask about performance and progression. Are output, colour and aim within limits, and is the defect stable or growing?
- Take the most serious answer. That answer, not the appearance, sets the class.
- Act and carry it forward. Respond as the procedure requires, then let the classified defects feed the asset’s condition grade.
Frequently Asked Questions
Q1What is defect classification in AGL inspection?
Sorting each defect found into a class by its effect, not by how it looks. In the example scheme, minor means no effect on safety or function, major means function or performance is reduced, and critical means a safety hazard or loss of a required function. The class sets the response and the priority.
Q2How is a defect classified?
By asking what it does. Is it a hazard to aircraft, vehicles or people? Does the asset still work? Is light output, colour or aim still within limits? Is it stable or getting worse? The most serious answer decides the class. A cracked lens that spreads the beam outranks a dirty lens that still meets its limits.
Q3What is the difference between defect classification and condition grading?
Defect classification sorts a single defect. Condition grading gives the whole asset one overall grade, taken from the worst of its classified defects. An asset whose worst defect is minor stays in a low-concern grade, while one critical defect puts the whole asset in the highest-concern grade.
Q4What response goes with each class?
In the example scheme, a minor defect is recorded and monitored. A major defect is planned for repair and re-checked. A critical defect is reported and made safe first, then repaired. The site's procedures set the actual response times.
Q5Who sets the classes and their limits?
The airport or maintenance organisation sets them in its procedures, using the manufacturer's data, the project design, the applicable standard and the operator's requirements. Class names and limits differ between sites, so the scheme shown here is an example. Apply your own site's scheme.
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