The Leapfrog was an experimental pusher aircraft developed near the end of WWII. The design was promising, but upon testing, the aircraft was uncontrollable. Luckily, help was called in and the aircraft was redisigned into a working model. The program, however, was soon cancelled and no leapfrogs were put into production.
This plane gave me a lot of trouble;so much that I gave up and asked for help. Thankfully, @Skua was able to help me(for the third or fourth time) and fixed its issues, so a special thanks to him!
Be sure not to turn on the runway, it is still a bit unstable. When in the air, it will be shaky until it reaches about 190 mph. It has a top speed of 230mph.