Continuity mistake: On the airplane, when Roy asks Johnny if he knows the flight attendant's name yet, the headset is around Roy's neck, but in the closeup it vanishes, then next shot it reappears again.
Visible crew/equipment: At the start, when Johnny is telling The Stewardess about the underwater rescue and in following shots, the outline of the lavalier mic wire and the dark strap (that holds the transmitter) around Johnny's waist are visible on the back of his shirt, and the mic transmitter is visible on the front, left side of his shirt, above his belt.
Answer: I believe you are speaking of the old man, Mr. Wilson. He's played by J. Pat O'Malley.
Bishop73
Correct, it was J. Pat O'Malley...he also played the grandfather with his grandson when their rocket exploded, and also played "Old Bill" in the episode with Ann Prentiss, where Gage saves the little girl from the burning tree house, and her mother falls in love with him.