Continuity mistake: When 51's guys are on the roof of the jail, Johnny sets up the red hose roller with a safety line on the roof edge between the two ladders, but when Roy climbs up the orange ladder to go over the edge, that hose roller with the safety line are not on the roof edge and can be seen still lying on the ground, then it reappears in place in the aerial shot. Additionally, when Roy goes over the roof to make his descent, there's a second silver hose roller at the base of the overhang, which was never actually placed there.
Visible crew/equipment: When Station 51 is dispatched to the plane crash, we hear Captain Stanley respond, "KMG365," and as he walks in front of the engine the partial reflection of the cameraman is visible on the windshield, right in front of Mike who's sitting in the driver's seat.
Audio problem: When Squad 51 is being dispatched to 'man unconscious possible heart attack', this particular view we have of the apparatus bay shows the brick wall where the bay's door track is located on the right of the screen, and we can see that the bay door is up, but when Roy turns on the squad's ignition, we hear audio of the bay door opening even though it's not actually closed.
Visible crew/equipment: When Roy and Johnny load the woman who fainted onto the ambulance, the curly haired attendant gets in the back with Roy and the patient, but en route Roy is alone with the patient, and when Roy tells them to pull over we see the silhouette of the curly haired attendant sitting in the front passenger seat. Then when the ambulance pulls over, only the driver is in the front.
Visible crew/equipment: When Roy's in the ambulance with the woman who fainted, he gets permission from Brackett to leave the TKO patient, so he and John can join Engine 51 at the traffic accident nearby. When the ambulance pulls over, the reflection of array lighting can be seen on the surfaces of both the ambulance and Squad 51.
Continuity mistake: When Squad 51 is dispatched to the possible heart attack, the address given is 11044 Conquistador, but when they arrive at the incident the addresses on the homes are 8042 and 8046.
Visible crew/equipment: At the scene of the plane that hit the building, after the explosion, when Foam 10 arrives there's a closeup of the firemen using the foam tubing, and behind the doorway one of the 'firemen' kicks the foam tubing, but notice that he's not really a fireman, he's actually a crew member who's wearing a turnout coat, though he's also wearing jeans and work boots.
Visible crew/equipment: When Mr. Laurents visits Station 51, as the guys stand up the actor's T-mark is visible on the floor, between DeSoto and Chet, just before Chet promptly stands at his mark.
Visible crew/equipment: After Johnny and Chet begin their arm wrestling, when dispatch drops the tones, there's movement at the front seats of Engine 51 where the camera is located, while Captain Stanley is at the radio base station and Mike is putting on his turnout.
Revealing mistake: After the husband and wife are pulled from the plane wreck, they're lying on the ground while Roy and Johnny are treating them. In this wide shot, which lasts about 12 seconds, Roy has no eyes or eyebrows, as part of his face has been blurred out, and when Roy moves his face it's quite bizarre to look at. This is visible on Netflix as well as the DVD, which was created in 2010 by Universal Studios, where Emergency! was filmed during its run on the air in the '70s.
Revealing mistake: At the structure fire at an abandoned building, when Engine 164 arrives we see that it has distinctive markings beside the driver's side door and tire rim. When Engine 72 arrives the same markings are in the same place, revealing that it's the same engine and they used different magnetic number decals for the engine.
Revealing mistake: When Station 51 is dispatched to "plane that hit building," after they rescue the two aboard the plane, just before the explosion when the orange combustible drum is propelled into the air, we can see the stunt's projectile to get the drum airborne.
Continuity mistake: After Roy explains to Mrs. Evans that she shouldn't call them every time Simba runs off, when Chet finds Simba, Johnny holds him with his right hand behind the front legs and left hand under the tail, but closeup Johnny's hands are in the opposite positions.
Visible crew/equipment: At the structure fire at an abandoned building, when Engine 164 arrives, we can see the reflection of the location's array lighting in the driver's side window.
Visible crew/equipment: After Johnny reads the note from Mr. Laurents, which he left with the package of money in the fridge, Captain Stanley walks over to the counter, where the actor's T-mark is visible on the floor.
Continuity mistake: Before Mr. Laurents walks into the station with the bag of money, Roy's holding the coffee pot with his right hand, then it's in his left hand, between shots.
Revealing mistake: At the site of the hang gliding accident, just after the glider falls, in the long shot when Johnny and Chet pull the unconscious victim higher on the cliff, the victim is supposed to be unconscious, yet we see him use his right leg to push himself higher up to help John and Chet pull him up.
Visible crew/equipment: When Roy is in the ER due to the dizziness, two actors' T-marks are visible on the floor near the door, where moments later Dr. Bracket and Dr. Early stand before leaving. Additionally, Dr. Early's mark (during The Exam) becomes visible when Dixie shifts her position, just as Dr. Bracket asks, "Any pain here, Roy?"
Visible crew/equipment: When Mr. Grady (self-defense instructor) is in the ER, being examined by Dr. Brackett, there is a visible T-mark on the floor behind Gage.
Visible crew/equipment: After Station 51 is dispatched to the fire at a singles club, when Engine 51 pulls into the parking lot it and then turns around, the reflections of multiple array lighting can be seen on the engine's surface and Mike's window when he opens the 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.