When should you go missed on a LOC approach?

In the context of a Localizer (LOC) approach, going missed means executing a missed approach procedure when you are unable to land safely. The correct answer focuses on specific points in the procedure that trigger a missed approach.

When flying a LOC approach, the decision to go missed is fundamentally tied to two crucial aspects: DME (Distance Measuring Equipment) readings or time-based intervals defined in the approach. If the aircraft has not reached a designated point, typically specified in the approach plate, which indicates that visual reference to the runway is not established, the pilot must initiate the missed approach. This can either be a specific distance from the runway (such as a DME readout) or a predetermined period following a descent that does not yield a clear view of the runway.

The other options focus on different trigger points such as reaching decision altitude or achieving visual contact with the runway. While these options may seem applicable, they do not align with the primary guidance for decision-making in the context of a missed approach that emphasizes the importance of defined navigational waypoints or time considerations as the key elements in executing such maneuvers. Additionally, following controller instructions is also a valid consideration, but this would typically occur after an earlier decision point has passed. Thus,