I'm a bit out of date here but...
The army certainly used to have observers, I believe that the crew concept now is for two pilots per aircraft.
(An army observer was always an NCO more often than not a L/Cpl or Cpl). He (for they were all he's then!) wasn't trained to anything like the standard of a Navy observer.
However, if (sweeping generalisation coming) the Naval pilot gets the aircraft to the scene of the fight and the Naval observer then 'fights' the aircraft. Apache aircraft commander with the army may be a comparable task. I'm sure that some newer fellow pongoes (or ex-pongoes) will be able to elaborate further when they've worked out how to switch the computer on
Ps before any apache dudes get miffed that I have compared the task of an army pilot to a navy observer, please re-read the post
