My dad flew KC-135’s, Huey Gunships in Vietnam as a Green Hornet, EC-135, F-111’s, and retired flying 135’s again. This is as a prior enlisted guy who enlisted in his 20’s (actually got drafted into the Army while at AF BMT). Earned the nickname of the “oldest Captain in the Air Force” in Vietnam.
The craziest part to me is that he was sent to the Huey as a thousand hour Tanker AC as a brand new 1st Lt. No casual time between training like now.