During an IAP, what is the first action a pilot should take if their navigation equipment malfunctions?

In the event of a navigation equipment malfunction during an Instrument Approach Procedure (IAP), the first action a pilot should take is to inform Air Traffic Control (ATC) about the issue. This is crucial for several reasons.

First, notifying ATC allows them to provide assistance and guidance based on the current situation. They have the capability to offer alternative routing, expedite handling, or assist in resolving the issue with the necessary situational awareness that comes from their radar and communication capabilities.

Second, keeping ATC informed enhances safety by ensuring that other aircraft in the vicinity are aware of the potential navigation issue. This promotes an overall safer environment as proper spacing and traffic management can be maintained.

While considering manual navigation methods is important, it is typically a secondary action that should come after communication with ATC. Executing a missed approach or diverting to an alternate airport might be necessary steps depending on the circumstances, but the priority must be to communicate with ATC to best assess the situation and determine the appropriate course of action together.