It was the Germans duty to shoot the B17 down. The Americans flew home landed replaned and we're back on the next mission to kill Germans. If the Americans had wanted to surrender they could have lowered their landing gear and put out their flaps, this was considered a universal sign of surrender. Is a very touching story but I've always felt that the German pilot should've been shot. How many of his comrades and countryman died because of his actions?
This was pretty much my reaction to the story. But after thinking about it awhile I realized what made this slightly different was that the German pilot could tell the majority of the crew was wounded. Part of the point of the Geneva conventions is that incapacitating the enemy's ability to fight is preferred to outright killing, and therefore helping preserve the combatants humanity.
Perhaps a pilot that wasn't mentally struggling with the political implications of his actions, and the threat of 50cal machine guns that could open up on him, would realize that the proper action was to clearly offer surrender. A hostile act at that point by the bomber crew would absolve him of any wrong in finishing off the bomber. The bomber crew surrendering when offered, would have made for almost as engaging story because of the bravery and humanity shown, but without the questioning the consequences of the German pilot allowing them to return to their airbase.
In AH I've never seen a badly mauled red guy surrender, land at the enemy field and become a POW. Nope they are bailing, ditching, or RTBing so they can up again to engage in another fight. So I might as well get the kill and perkies. One time, though, I really wished I had been left to try to RTB in a lone remaining B17 with no ammo, no rudder, no ailerons, one elevator, and one inboard engine out. Would have been fun to see if I could've landed it.