Other mistake: During the rescue at the top of the open drawbridge, in the shots of Engine 2 we can see the red, vinyl material with the company number imprinted on it, adhered to the front of the engine.
Other mistake: When Station 51 is dispatched to 'man trapped in vehicle', we can see the real Station 127's vehicle is still parked inside the apparatus bay, near the rear bay door.
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.