My father was with the 13th Air Force in the PTO. He told of one time a bomber got hit in the tail with flack. They hosed the tailgunner out in the grass along the runway. I am finishing a book about Gregory Boyington, the subject of the TV series, Baa, Baa, Black Sheep. I wonder how many 18 year olds would survive just the jungle- heat, humidity, bugs, disease, etc. My father had jungle rot for years. Doctors couldn't treat it. Finally, a doctor in Queens, NY, cured it. Told dad to do exactly what he says. Coat it with an ointment, wrap your lower leg with Saran wrap to keep air out. It worked.
If you want to read a good book, get a copy of 365 Days by Ron Glaser. He was a doctor in Zama, Japan. The book is a collection of stories of Viet Nam troops.
Life is like water-skiing; if you slow down, you go down.