What action should a pilot take if more than one component of an ILS is unusable?

In the context of an Instrument Landing System (ILS), if more than one component of the system is unusable, the pilot must ensure their approach adheres to the highest minimum required by any single component that is still functional. This is critical for maintaining safety during the approach, as different components of the ILS provide vital information about altitude and lateral alignment with the runway.

Each component of ILS, which typically includes the localizer, glide slope, and marker beacons, has specific minimums that dictate safe operating parameters. If one of these components is inoperative, the minimums associated with the functioning components become paramount. By opting to use the highest minimum requirement, the pilot can proceed with increased caution, ensuring they have the best possible chance of a safe landing despite the compromised system.

The other options do not prioritize safety effectively. Using the lowest minimum could lead to an unsafe situation, as the pilot may inadvertently descend below safe thresholds dictated by operational criteria. Aborting the approach could be unnecessarily conservative if there are still functional components that meet higher standards. Continuing the approach without adjustment ignores the need for a safety buffer dictated by the available ILS components. Thus, adhering to the highest minimum ensures that the pilot is taking the most prudent approach under the