Navy Seawolves
 
Det 4
 
HC-1 Det 21 Deployed to Vietam in November, 1966, operated from the USS Garrett County (LST-786), under the command of OinC LCDR George (Rocky) Rowell. Flew with Army gunship companies, entered combat early 1967 when it was redesignated HC-1 Det 4 just prior to commissioning of HA(L)-3.