In the campaign, specifically episode one, Kerry and others call SSgt Adams "Sir" several times. "Sir" is reserved for Commissioned Officers ONLY, with the exception of USMC Basic Training, which has no relation to the campaign.
Additionally, the helicopter pilot calls Adams "Sir" as well, implying that he is enlisted. Helicopter pilots are required to be Commissioned Officers, so this also makes no sense.
This issue really ruins the immersion of the campaign for me, because, frankly, it feels like the people who wrote the lines knew NOTHING about military protocol. Arma, of all games, should abide by the real-life rules.
Thanks guys and happy line-changing! :)