I would say the pilot's actions are "good". In fact, the tougher the decision he has to make, the "better" his action is. He has a mission which is greater than a single life, even if it is the life of an innocent girl who sneaked in on the ship to see her brother. It is extremely hard to jettison her, but he has to sacrifice one life to save many. He has this moral dilemma, and wishes she weren't an innocent girl, but a tough old man who knowingly broke the rule: "Why couldn’t she have been a man with some ulterior motive? A fugitive from justice hoping to lose himself on a raw new world; an opportunist seeking transportation to the new colonies where he might find golden fleece for the taking; a crackpot with a mission." He also tries to find a way out by calling the emergency commander, to report the difficult situation.
Another reason why his action is "good" is that the girl would die anyway - even if she wasn't jettisoned, the ship would run out of fuel and crash, causing seven other people (the pilot and the six people waiting for him to arrive) to die too.
