What Constituted A Mission

I was just listening to an interview form a fighter pilot from the 325th Fighter Group that was stationed in Italy and he said that if you were on an escort mission and the bombers didn't reach the target then it didn't count toward their mission count. This included missions where fighter pilots would engage with the enemy in battle. I have never heard that before and was wondering if there were other rules about what made a mission an official "mission".

It varied with place, time, and leadership. In Operation Desert Storm, my crew and I served as airborne spare on two missions. One was counted as a "combat mission" because we crossed a certain line (coast of Oman if I recall correctly). The other counted as a "combat support mission" but not a "combat mission" because we returned to base before crossing the magic line.

Chuck