What action should be taken if the distance to the DME station continues to decrease during a TACAN approach?

When executing a TACAN approach, the primary goal is to maintain an established course towards the station. If the distance to the Distance Measuring Equipment (DME) station continues to decrease, this indicates that the aircraft is closing in on the station as intended.

Continuing on the course is appropriate because it confirms that the aircraft is effectively following the established approach path. This action suggests that you are positioned correctly within the required flight parameters, and there is no need to alter your flight path as long as you are adhering to the prescribed altitude and approach guidelines.

In the context of overall situational awareness during an approach, maintaining a stable flight path where the DME distance is decreasing aids in ensuring the approach is being executed correctly, thus allowing for a safe landing phase.