Unlimited Wings

アンリミテッド・ウィングス From here:

Elizabeth Whitehead is a foreign teenage girl with a terminal illness who is particularly fond of air races. When she needed a new engine for her airplanes, she goes to Japan to a famous smith, Aramaki. Aramaki has stopped making jet engines as he still hasn't forgiven himself for contributing to WWII, but upon hearing Elizabeth's situation, he offers his services.