Dr. Slump: Arale-chan - episode 12 - 30 Jun, 1981

Dr. Slump builds a gun that transforms whatever the gunner chooses. Arale uses it to turn Yamabuki into Slump's wife and then turn the doctor into a sea monster. Arale wants to fly like Gatchan, so Dr. Slump builds her a flying machine. After a test flight in it, Arale lands on the Weatherman's domain and plays about with the weather. (Source: Wikipedia)