You mean Billy Nelson? He is in season 2 also. At one point in season one "The Celebrity," about a fictional major leaguer named Del Packer who joins the squad, Billy is very badly wounded and in the last scene, the ball player (played by Tab Hunter) comes to visit him and the bed is rolled up and Billy is gone (died?). Naaah. Even though the episodes are pretty mixed up chronologically among the seasons, Billy is alive and well in many more episodes in the first and second seasons.
Any more questions, COMBAT! fans? Kirby, take the point!