400 reference questions on finding and fixing faults in an AGL installation: CCR and series circuit faults, insulation, isolating transformer, connector, cable and light fitting problems, control system faults and field troubleshooting, with the safe-isolation, test-selection and root-cause thinking behind each.
Every question traces back to one of nine fault topics, from the CCR and the series circuit through insulation, transformers, connectors, cables and light fittings to control systems and field troubleshooting. The bank leans toward working-engineer depth: symptom-first diagnosis, test selection, root-cause reasoning and repair decisions, with references mainly to FAA AC 150/5340-26C.
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A shuffled run through the troubleshooting & maintenance bank. Type your own answer and check it for a score, or just reveal the model answer, then move to the next card.
Short answers about the troubleshooting & maintenance question bank, how the drill and scoring work, and the standards it refers to.
It is a 400-question reference and drill on finding and fixing faults in airfield ground lighting: CCR faults, series circuit faults, insulation problems, isolating transformer problems, connector and cable faults, light fitting failures, control system problems and field troubleshooting. Every question has a model answer, an explanation, tagged key terms and standards references, and the whole bank is searchable, filterable and drillable on this page.
Nine topics: CCR Faults (50), Circuit Faults (50), Insulation Problems (40), Transformer Problems (45), Connector Problems (40), Cable Faults (45), Light Fitting Failures (45), Control System Problems (40), Field Troubleshooting (45).
Four levels: Beginner (52), Intermediate (157), Advanced (160) and Expert (31). The bank leans toward working-engineer depth, with about 87% of questions at Intermediate or above. If terminology is still new, start with the AGL Fundamentals bank first.
Questions are grouped into seven formats: technical explanation (127), troubleshooting and diagnostic sequences (82), scenario-based and case-study questions (50), root-cause analysis (39), testing and measurement (33), maintenance and inspection (37) and standards interpretation (32).
Drill Mode gives a shuffled run through the bank, filtered by level and topic if you choose. Type your own answer and check it, or just reveal the model answer. Typed answers are marked with weighted key-term matching (with stemming and typo tolerance) plus overall wording overlap. It is a close local approximation of a marker, not true AI grading, so use it to spot gaps rather than as a formal assessment.
When one light is dark and the rest of the series circuit operates normally, the fault is usually local: the lamp or LED source, the fixture connection, the secondary connector, the isolating transformer secondary or the local wiring. If a replacement light also fails, or a string of lights fails, the fault is more likely in the series circuit itself, and the fault-finding sequence moves to the circuit.
Most references point to FAA AC 150/5340-26C (maintenance of airport visual aid facilities), with supporting references to FAA AC 150/5345-10H (constant current regulators), AC 150/5345-26E (connectors and splices), AC 150/5345-47C (isolation transformers), AC 150/5345-56B (L-890 control systems), AC 150/5345-7F (cable) and AC 150/5345-46F (light fittings). Some answers also cite manufacturer manuals, so always confirm against the current edition and the equipment documentation on your airfield.
Yes. Fault-finding and maintenance judgement are a large part of technical AGL interviews, and this bank is built around them: symptom-first diagnosis, safe isolation, test selection, root-cause reasoning and what to do next. Use the explorer to read model answers, then use Drill Mode to practise explaining your own reasoning.
Regulators, series circuits and protection, the systems these faults live in.
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