Tinkerbell is a female engineer heroine. So the first competent Disney engineer is a fairy. I'm glad that Disney has finally honored us engineers with a lead character considering that up until now, Disney engineers were abysmal. We had Belle's father, "crazy, old Maurice" whose wood-chopper nearly decapitates his daughter with flying logs. For civil engineers, there was the beaver in "Lady and the Tramp" who seems competent, since he nearly finishes a dam, but is vulnerable to charlatans who pass off a muzzle as a log-hauler and is so uncoordinated that he almost brains himself in his own backyard. Not a sterling selection.
Actually, I did forget one competent engineer though he has no lines and dies in the first ten minutes of the movie, Tarzan's dad is an engineer to admire. He builds a treehouse with pieces of a shipwrecked boat and keep his family alive for weeks in a hostile land, ultimately giving his life to save his son. We need more engineers like that.