The Colour Vision Referral
A candidate applying for a pilot role has passed every stage of assessment except the medical colour vision test. At the initial screening he correctly read all plates in the standard screening test, but when the medical officer used a more detailed test (a lantern test with red, green and white lights shown at 6 metres in dimmed room lighting), he misidentified two of nine red lights as white and one green light as white. He has no history of eye disease, wears no glasses, and his visual acuity is 6/6 in each eye. He tells the medical officer that his father is also red-green colour deficient and that he has 'always struggled a bit' to tell red and green wires apart when doing electrical work at home. He is otherwise fit, has a clean history, and the recruiting team is keen to keep him because he scored highly on the aptitude battery. He asks whether he can simply be re-tested next week after 'resting his eyes'.
1. Identify the key finding that determines this candidate's fitness for pilot duties, and explain why the initial screening result does not settle the question.
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The decisive finding is the failure on the detailed lantern test combined with his own reported difficulty distinguishing red and green, not the clean screening plate test. Screening plates are designed to be sensitive but are a first filter; a candidate can pass them and still have a colour vision defect that shows up on a more discriminating test. The lantern test simulates the real operational task - identifying signal and navigation lights at distance in poor lighting - and he misidentified 3 of 9 lights, including mistaking reds for white. His self-report of struggling with red/green wiring corroborates a genuine red-green deficiency rather than a testing artefact. For pilot duties, colour vision is a safety-critical requirement because aircrew must distinguish red, green and white lights (e.g. port/starboard, warning and signal lights). A confirmed defect of this kind is normally disqualifying for pilot roles, and the correct action is referral to the medical authority for formal classification, not reassurance.
2. The candidate asks to be re-tested next week after resting his eyes. Explain whether this is a reasonable request and what the medical officer should do.
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Re-testing after rest is not a reasonable route to a pass here. Rest, hydration or better lighting can affect borderline acuity, but they do not change a congenital red-green colour vision deficiency, which is what the evidence points to (family history plus self-reported difficulty plus consistent misidentification of reds and greens). Repeating the test would only reproduce the result and could create pressure to 'shop' for a favourable outcome. The medical officer should: (1) explain that the finding is consistent and not fatigue-related; (2) record the lantern test result and the candidate's history accurately; (3) refer the case to the aviation medical authority for formal assessment and classification; and (4) discuss the outcome honestly with the candidate, including that a confirmed defect is likely to make him unfit for pilot duties. If service policy allows, the recruiting team may consider him for roles without a colour vision requirement, but that is a separate decision and must not be used to override the medical finding.