The main US aircrew sidearm was the .38 cal. Victory Model revolver. Most fliers preferred it when available because it was lighter than the .45 auto. (Col. Dave Schilling of the 5t6FG had the ordies make him a 20-round magazine and a forward grip on his full-auto gat.) At least in some SW Pacific bomb groups, standard equipment was a 12-gauge shotgun with a box or more of 00 buckshot. Usually aircrew traded those to the marines/GIs for other stuff.
All these decades later, internet legend holds that the M1911 was notably inaccurate. Not so. At all. There are two factors: army recruits were trained on WW II production for decades thereafter--the guns were rattling loose. The other trouble was that the army did a marginal job teaching how to shoot it, especially with the one-handed, full arm extended target stance. I have shot several wartime 1911s and they range from OK to superb. I have the last 1911 that Joe Foss carried on active duty, and the last time I shot it (his 100th birthday) it tried hard to hold 2 inches for 3 rounds at 20 yards.