Beachhead covers a simulated amphibious assualt with marked similarities to D-Day in the real world. It is part of The Concourse to Victory, the third volume of the Course Books. The assault is a live-fire tactical drill carried out in one of the school's Simulators (a large simulated-reality environment), wherein Hunter is supposedly commanding the attack, but does little other than run around shooting bad guys and nearly blowing Jason up with a grenade.
This story stands mostly as an illustration of the teaching methods employed by Gudersnipe School, which consist primarily of throwing the students into a controlled yet dangerous environment and watching them squirm. Though not mentioned in the story, excercises like this help the school determine which students will do well in combat scenarios and which should have less bullet-oriented careers.