Each of the four ACH-47's went by Go-Go (plus the last two numbers in their tail number), but that was only between aircraft in flight. The unit Call Sign was commonly "Go-Go Birds" early on ('66 thru mid '67), but became "Guns A Go-Go" exclusively from mid '67 until they de-activated in March '68.;
During the time they were being evaluated in Vung Tau (Apr '66 - Dec '66), they were attached to the 147thASHC, but when they went north to An Khe, they were attached to the 228thASHB.
I had no idea you were involved in a project such as this. I was a door
gunner with Guns-a-GoGo form 1/67tthrough 9/67, and as I recall, we always
used "GoGo154, GoGo 149er, and GoGo 145" depending on which ship was
calling, the three numbers being the last three tail numbers of the
aircraft, for our call signs.
On on mission, the VC got on our frequency and called us "Gogo 154, stop
shooting at the purple smoke! Friendly troops at the purple smoke!" all in
perfect American English! We did a check in with our operations and of
course learned that there were no friendly troops, other than the LRRPs we
were rescuing, and used the purple smoke for our target. We got the LRRPs
out with no casualties, but I can't say the same for the NVA.