In the early 1940s Walt Disney was developing a feature film based on Roald Dahl's book "Gremlin Lore", and asked the other studios to refrain from producing gremlin films. While most of the studios complied, Warner Bros. already had two cartoons too far into production - this cartoon and Russian Rhapsody. As a compromise, Leon Schlesinger re-titled the cartoons to remove any reference to gremlins. The original title was "Bugs Bunny and the Gremlin".
In the opening scene, Bugs is reading a book titled "Victory Thru Hare Power". It's a spoof on the title of "Victory Through Air Power", by Maj. Alexander de Seversky, published by Garden City Books, NY, in 1942.
Just after Bugs Bunny unknowingly ran outside the flying airplane, he turns into a donkey with 'JACK-ASS' written on his left side.