1. It is called 3 times to make sure that someone hears the emergency call when there is back noise.<br />
2. It is used as a emergency distress signal.<br />
I am a pilot and have used this only once, and I know that it works..<br />
GOOD QUESTION.....MASTER GILEY
it is also called 3 times to make sure it is not part of a normal conversation... same applies to similar calls like pan-pan
It would sound weird calling, December day December day!!