Sidney Sheldon managed to persuade his neighbor Groucho Marx to come out of retirement to do a cameo. Marx made it clear he didn't want to be paid money for his brief appearance, so that he wouldn't have to pay taxes on it. Therefore, the show's special effects man Richard Albain was asked to install a state of the art RCA color television in Groucho's home, complete with stereophonic speakers and a phonograph table. A possibly apocryphal addendum goes that when Marx found out that the package did not include a remote control, still a rare luxury in 1967, he ordered the whole thing removed.
The fighter jet at the beginning that Tony "flies" and lands is a Lockheed F-104 Starfighter.
The footage of Tony in a landed plane removing and passing his flight helmet to a colleague is also used 2 episodes later. The remainder of that footage has Tony climbing out of the plane and walking away from it talking with Roger. The entire footage is taken from an earlier season 2 episode, the difference being that the sound is removed here, particularly the conversation with Roger in which dialogue is heard in the earlier episode.