Flying Leathernecks begins when Major Dan Kirby (John Wayne) gets a new command. The command is a surprise to a group of “Wildcat” pilots who were hoping the popular and somewhat lax Captain Carl Griffin would lead their campaign. Kirby is your tough-as-nails career military man, and lets it be known he’s not going to take guff the moment he arrives.
Kirby’s assignment in the Guadalcanal campaign struggles with a lack of planes, daily attacks from the Japanese, and a group of young pilots that act like the young kids they are. To add to the conflict, Kirby’s executive, Captain Griffin doesn’t display a willingness to make the decisions that can lead to his pilots deaths, which he eventually blames on Kirby.
As the war of attrition continues, Kirby has to become more strict with his men as the become more tired from the constant missions. Griffin withdraws from Kirby even more.
In the climatic battle, Griffin makes the tough decision not to split from his formation to help his brother-in-law, Blithe, when he has engine trouble and is surrounded by Zeroes. That decision gets Blithe killed, but proves to Kirby that Griffin does indeed have the mental toughness to command.
During the melee, Kirby gets shot down, and his broken arm leads to him to a desk job while he recuperates. Kirby recommends that Griffin be promoted to his old command. The film ends with the two men promising to meet for drinks after the war.