My grandfather was a B-24 pilot in Italy, and he carried a 1911. Seeing as how many of the pilots from Italy went on to the Pacific after VE day, I would think that they would have carried the same thing.
As far as a "crewman", I'm not sure if everyone was issued a sidearm in a B-24 or only the officers. According to Ambrose's "Wild Blue", everyone on board a B-24 was a sergeant or better, but my grandfather's brief memoirs claimed that most of his enlisted crew were privates of some variation. I wish he was still here for me to ask him for you.
My step-grandfather (sadly also passed on) was a fighter pilot, but I know very little about him or his career. I do know that he was quite a celebrity around Eglin AFB, and was one of the fighter pilots to make the switch from props to jets. He was also a member of the predecessor to the Blue Angels. For the life of me I cannot remember the name of this group.