Coordinates and a missing integrity function
A fictional navigation-system display continues to show plausible coordinates while a separate status message says that the integrity-monitoring function required for the hypothetical task is unavailable. The exercise explicitly requires that function and provides no approved alternative sensor or operational exception. A learner dismisses the status message because the map symbol has not jumped. Another assumes that any working position display automatically grants permission for every instrument procedure. The task asks what the display does and does not establish. No current aircraft approval, actual flight, approach phase or instruction to continue or go around is given. A suitable answer preserves the distinction between a computed position and the performance assurance required for its intended use. It should not invent a backup capability or a legal authorization absent from the scenario.
1. What does the plausible position display fail to establish?
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It does not establish that the separately required integrity-monitoring function is available. A reasonable-looking coordinate is not proof of the assurance required by this exercise.
2. Can an unstated backup or approach permission be assumed?
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No. The scenario supplies neither. Actual operations would require the applicable approved procedures and capability evidence, rather than an invented exception based on the map symbol.