The main air defense for American CV's on Yankee Station was their own CAP(Captive Air Patrol). In other words>>>The CV's own fighters. They maintained a condition of 5 minute alerts. That is the aircraft could be launched or respond in 5 minutes time. The alerts were generally in 5 minute increments..Generally not going over 30 minutes. Alert times depended on the previeved threat.
As for ships the old Gearing class DD's were "Plane Guards" there responsiblity was to keep other vesels away from the CV and to assist in the rescue of downed piolts. I assume that any other USN or allied ship would provide AAW if needed and if the ship was so equipped.
In country in S.Vietnam..Well I have no idea.
What ever sort of defense the USN put up against North Vietnam must have worked. The N. Vietnamese never launched any sort of air attack against any American CV in Yankee Station.
In my opinion an USN CVN should be named
USS Yankee Station.
I was onboard the
USS Hancock CVA-19 during Operation "Eaagle Pull" & "Frequent Wind" in 1975.
http://www.sinodefenceforum.com/showpost.php?p=33477&postcount=1