Strange that you say that. The day I got off the Huey at our NDP (open AO for staging etc aka Night Defensive Position) my new CO that I had never met before walked up to me with my orders in his hands and asked if I was artillery and I replied yes, that I was. He next asked me if I'd had any cross training as an FO and I replied, yes, some. He says good, you're my new FO for F Troop. He explained that in a major firefight that day he'd lost two of his three FO's due to being seriously injured in said firefight and they were dusted off and later went home.
The strangest part is that was mid 1970 and we at the moment were staging off the Gulf of Tonkin and sweeping the area 2 and 3 klicks at a time non stop. One week later we loaded up and went cross country to the Iron Triangle en force. Took two whole days to move that many troops and equipment, Battalion force in size along with three companies of Rome Plow units, 90 of them in all. 87 D10 Cats equipped with tree cutting blades and 3 D9 bull blade Cats. We dug a many deep mass graves with the D9's and buried as many 200 enemy dead bodies in them at a time and sometimes dug three a day of them after a major fire fight/encounter.
Small world. Earl’s track got hit with an RPG and he was cut up with fragments badly enough to get sent back to the us.