When is it appropriate to call KIO in ET?

Calling "KIO" (Knock It Off) is a critical safety protocol used during formation flying, particularly in the context of the T-6 aircraft. This call indicates that the current exercise or maneuver should be aborted due to safety concerns or a significant risk of collision.

The appropriate time to call KIO is when busting the 3/9 line. The 3/9 line refers to an imaginary line extending outwards from the aircraft at the 3 o’clock and 9 o’clock positions. When an aircraft crosses this line, it indicates that the separation between formations has decreased to an unsafe level, increasing the risk of a mid-air collision. Thus, calling KIO in this context allows for immediate corrective action and a reassessment of the situation to restore safety.

While there may be situations that imply a need for caution, such as not being in formation, entering a cloud, or flying below minimums, the specific call of KIO is primarily associated with the fundamental parameters of maintaining safe separation and awareness in formation flight, particularly regarding the critical 3/9 line.