What is the first action to be taken in a KIO call with radio failure?

In the event of a KIO (Keep Informed) call with a radio failure, performing continuous wing rock is the appropriate first action to signal to any other aircraft that you are unable to communicate effectively due to the radio failure. This visual signal is a recognized gesture in formation flying that indicates there is a problem, and you need to get the attention of lead or other formation members.

This method serves to inform others that you are not capable of maintaining normal communication, while also allowing you to stay aligned with the flight's maneuvers and maintain situational awareness. The use of wing rocks as a visual indication is crucial in maintaining safety and ensuring other flight members are aware of your status.

Initiating a climb, contacting ground control, or turning toward the intended destination could potentially add confusion or exacerbate the situation, especially without the ability to communicate clearly about your intentions. Thus, the continuous wing rock serves as the most immediate and effective way to alert others while managing a radio failure.