After a tough mission, Gallagher needs a new gunner. Corbett, a replacement has a perfect gunnery score (1000, Komansky only has 400). He takes over from the wounded Staff Sergeant Abbott as Left Waist gunner & joins Gallagher's crew on a practice mission. He spots the target first but his gun jams. The other gunners kid him and he does not join in the after hours fun at the Star & Bottle. Komansky adopts Corbett and helps him, they go to another pub and Corbett meets Gillian. On the next practice mission, Corbett spots a real German FW and shoots it down. He gets promoted to Sergeant but is upset by killing someone. He checks in to the hospital, confesses to being only 15 and runs away to see Gillian at the pub. He comes back to see Gallagher and sneaks aboard for the next mission. Hachensberg is the target. After the other gunners are hit Corbett takes over ands performs well. On the return Gallagher chews him out and says he will get court-martialed. After he is taken away Gallagher