a transported unit inside an arial WE may do nothing except shoot with the aircraft if it lands, or engage with it, this counts as their activation
rulebook section 4.2.5 wrote:
Note that the limitations that apply to units disembarking from a war engine transport vehicle also apply to units disembarking from an aircraft (ie, they can’t take an action on the turn they disembark but can shoot with the aircraft – see 3.1.3)
they count as one formation until the action is resolved
rulebook section 3.1.3 wrote:
In both cases, the war engine and the transported units are treated as a single formation until the shooting attack or assault has been resolved.
if you barge with the aircraft then yes you have to disembark all passengers if they want to activate, they can then either engage or fire with the aircraft as per the previous replies (apologies if I have misunderstood the question)
