Yossarian does grow and change as a character, but he is always an antihero. Early in his military career, while stationed at Lowery Field, Colorado, in 1942, he discovers the joy of malingering and the refuge of the hospital. He fakes appendicitis, avoiding training as he begins a long, loving relationship with hospital life. A helpful English physician suggests that Yossarian should fake a liver ailment rather than appendicitis, the former being much more difficult to diagnose and treat.
Structurally, the novel opens and closes with hospital scenes. The hospital is Yossarian's home away from home and much more civilized than the war front. People die in hospitals, but they do so with more decorum. There is less screaming, and death is seldom a surprise. One of Yossarian's happiest Thanksgivings is spent in the Lowery Field hospital; it is so good that he considers spending every Thanksgiving in a hospital. But by the time the protagonist is in cadet training, at Santa Ana, California (1943), he is having an affair with his commanding officer's wife on Thanksgiving, still indulging in behavior atypical of a classic hero.
Bombardier Yossarian arrives on Pianosa early in 1944. That spring, he performs a feat that might be considered heroic; he lives to regret it. The squadron has been trying to destroy a bridge at Ferrara for a week without success. On yet another raid, Yossarian is unable to release his bombs on the first run. He orders his flight to take a second pass at the target. This time, he succeeds in knocking out the bridge; but a young airman named Kraft is killed. Kraft's death haunts Yossarian despite the fact that Colonel Cathcart decides to promote Yossarian to Captain and award him the Distinguished Flying Cross. Yossarian has had enough of heroics.
