"B. All Army personnel in uniform are required to salute when they meet and recognize persons entitled to the salute. Salutes will be exchanged between officers (commissioned and warrant) and enlisted personnel, and with personnel of the Armed Forces of the United States..."
Sir - You should always following regulatory guidance and salute anyone senior to you in rank.
SGM James
I've read several responses, but the question is asked
"2LT salute a 1LT?" By regulation, yes a salute is warranted to
someone of senior rank. When I originally commissioned in the AV branch, I
found it to be a different world and was corrected the first time I saluted a
1LT. And you'll see that W1s won't salute CW5s (at least in AV, not sure about
WOs in other branches), but according to the Warrants that were 50/50 in AV
BOLC with me, they state "it's an unwritten code in the Warrant Officer
ranks." The problem with creating, and continuing to follow, this
'standard' is the poor example it sets for those around that see this. The
snowball effect is very evident and then the question comes for that SPC or SSG
wondering why the junior WO doesn't salute the senior WO. Same can be said for
2LTs and 1LTs. Unfortunately, It's become the environment in which we find
ourselves, and it's going to take a lot of us to correct and set the right
standard.


Officers
Customs and Courtesies
Army
Saluting
AR 600-25
