Jimmy was a great actor. And from what I've read about him, a good airman as well.
At the height of his career, up to that point, and as Hollywood's #1 male lead, the volunteered for the US Army Air Corps in late 1941 right after Pearl Harbor and trained as a pilot.
Superior officers, not wanting to risk losing such a huge star, tried to keep him safe. He was assigned cushy jobs stateside as a pilot instructor.
But he wanted to do more. Jimmy had to FIGHT to get into combat. He flew heavy bombers, and rose to command a Bombardment Wing.
He was awarded the Distinguished Flying Cross, and became one of the few Americans to rise from Private to full Colonel in just 4 years.
After the war, he remained in the Air Force Reserve, attaining the rank of Brigadier General (that's one star). He flew one mission as an observer in a B-52 during the Vietnam War.
From everything I have read about the man, he was a humble, down to earth fellow.
Flying bombing missions as a commander, he led from the front, and it really hurt him to lose his men, his friends, in combat.