This is a short story written prior to 1990, possibly significantly earlier. The plot is about a dogfight between a man piloting the latest generation of fighter jet, which had a built-in artificial intelligence, and several previous-generation enemy fighters.
I think maybe when the story begins, the pilot is on a test flight by himself or maybe just flying a patrol mission. If he is with other planes, they are destroyed shortly after the enemy jets are encountered. The pilot does his best, but, being outnumbered, he eventually takes a hit from a missile or gun, and the shrapnel hurts him badly.
As soon as he passes out (from blood loss?), the AI takes over completely and, in a short space of time, defeats all of the enemy fighters by virtue of having faster reactions and being able to maneuver at higher G's than a human can handle while remaining conscious. As the fighter returns to base, I think the closing lines are something along the lines of how the fighter cared tenderly for the pilot or similar.
Note that the AI of the plane is specialized for its function and is not human-like; it doesn't talk or anything like that. Also note that this is a fighter plane intended for operation in air, not space.
The only interesting thing of this otherwise unremarkable story is that I believe it is implied without saying outright that humans had become obsolete as fighter pilots. I believe the new jet is described to the pilot as being full of features to assist him, but, in actual combat, he only lessened its effectiveness.