What is the required action when tuning to a VOR frequency?

When tuning to a VOR (VHF Omnidirectional Range) frequency, the required action is to activate and identify the station. This involves not only tuning the aircraft's VOR receiver to the correct frequency but also confirming that the signal you are receiving is indeed from the correct VOR station.

To identify the VOR, you usually listen to the Morse code identifier transmitted by the station, which helps ensure that you are locked onto the correct frequency. This process is crucial for navigation accuracy and safety. A pilot who only tunes in a frequency without verifying the identity of the VOR may mistakenly navigate using an incorrect signal, leading to navigation errors.

Other actions like just tuning the frequency without identification or merely tracking the signal without verification do not meet the necessary requirements for ensuring proper navigation. Maintaining altitude is unrelated to the procedure for tuning and identifying a VOR frequency, as altitude management is a separate aspect of flight operations.