This is a classic animated film, tell me what it is?

There's this movie about some sort of creature be it a mouse or a possum... and their little house in the woods burns down in the start of the movie. But the main storyline is that she builds this flying machine and travels around the skies, meeting all these other characters... I'm not exactly sure how it ends but it's AWESOME! Pleeeassseee tell me what the title of this movie is?? I can't for the life of me remember!