Americans are awake.
Post characters saluting
navelsalutes have the elbow tucked in?
The US Navy certainly doesn't do it.
On an added note, salutes in anime and its fanart are really half-assed or just improper by military standards. Even if you were to ignore hat most of the time they don't have a hat on, they usually do some lazy from the elbow salute like the boat sluts, or even worse, salute with the left hand.