Other mistake: When John, Roy, and Vince grab the officer who was shot by the sniper and make a run for it, as they duck behind the car, right behind them we can see a city bus just driving on by the lot, directly in the sniper's line of fire, even though that area's supposedly closed off with heavy police presence.
Visible crew/equipment: When Station 51 is dispatched to a man over the cliff, while en route there's a shot from the top of Engine 51, with the dome light in front of the camera, and the reflection of the covered camera, which is mounted on the engine's roof, is visible in the dome light's chrome surface.
It's How You Play the Game - S4-E19
Visible crew/equipment: When Johnny and Roy get the car salesman out of the car with the tiger, and when Johnny gets into the ambulance with him, the outline of the mic transmitter is visible at the side of Johnny's shirt.
Continuity mistake: When the guys come out and are watching Herbert leave, they are all in their turnout pants. Stoker is wearing turnout pants with the blue jacket zipped. When the tones drop for the call, the guys go to the vehicles and grab their turn out jackets and Stoker is in his blue pants and blue shirt pulling on a turnout coat. Not turnouts and no navy jacket.
Continuity mistake: When Gage goes into the lion enclosure you see the lion up high roar with sharp white teeth but the other shots the lion is now an older lion with broken rotten looking teeth.
I'll Fix It - S4-E2
Continuity mistake: While Roy and Johnny are under the house with the oil eruption trying to free the trapped man, they get covered in black oil and mud even though they're wearing turnout coats. It drips down their necks and their pants are soaked with it. When they get to Rampart with the victim, Roy says that he and John should get washed up, but when they talk to Dixie they haven't just washed up, their clothes are now impossibly spotless.
Continuity mistake: After Chet sees The Mouse run under the fridge, when the guys are discussing The Mouse Johnny's medical holster is clipped at his right hip, but when they're dispatched to 'man unconscious at laundromat' his medical holster is now at his left hip as he walks to the squad.
It's How You Play the Game - S4-E19
Character mistake: On scene at the vehicle accident, John palpates a pulse on the driver's leg and tells Roy that he's got a good strong foot pulse. Then when Roy's on the line with Rampart we hear him say, "He has a strong fetal pulse," but presumably Roy certainly must have meant to say, "strong pedal pulse."
Continuity mistake: When Roy and John are at the nurses' station talking to Brackett and Dixie about The Old Engine, at the bottom right corner of the screen we can see the patient's metal clipboard chart being held, before Early even walks over to the nurses' station holding a chart. Then when Early does walk over he stands to Brackett's right, but in shots facing Dix and Johnny we still see that chart being held, where Roy is supposedly standing, not Early. Additionally, the charts hanging on the chart holder change/vanish between shots.
Continuity mistake: At the scene of the traffic accident involving the car and the armored truck, the chrome center of Squad 51's lightbar is backwards, the solid side is facing front and the vertical slats are facing the rear.
Continuity mistake: When Mrs. Evans complains to Dixie that she's been waiting two hours to have her cigarette burn taken care of, in her closeups her handbag strap is over her shoulder, but in wide shots her handbag is hanging from her arm.
Continuity mistake: Roy and Johnny are at the nurses' station discussing the problem of non-emergency calls for paramedics, then it cuts to Dixie in the waiting room, when a nurse asks Dixie if the ER can take a pediatric patient who needs treatment immediately, and Dixie tells her to go to Morton in treatment 3. Then when Dixie speaks to Mrs. Evans we see that young girl being brought to treatment 3. During the next two minutes while Dix walks up the hallway, she quickly speaks to Brackett, then to an impatient parent, then to that nurse again, then Brackett again, and finally to Roy. When Roy asks Dixie where Johnny is, Dixie tells him in treatment 3 (dubious how she would even know that fact), and when Roy walks in to get Johnny that pediatric patient who was just brought to treatment 3 is not in there, instead Morton is examining Wild Bill.
Continuity mistake: After Johnny and Roy get back to the station and find Bill, who's filling in for Chet, in the kitchen cooking Chet's awful stew recipe, the tones drop and Squad 51 is dispatched to "man unconscious." Just as the bay door opens we can see Engine 51 parked in the bay, but when the squad heads down the driveway the engine's now gone. This presents another problem, because if the footage shows the engine gone, then why is Bill still at the station cooking stew instead of being with the rest of the engine company?
Camera Bug - S4-E10
Continuity mistake: When Roy's using the Ambu bag on the unconscious teenager from the school fire, while the stretcher's being wheeled to treatment 3's door, Roy has a stethoscope hanging around his neck, but in the next shot as they enter treatment 3 the stethoscope has vanished.
Revealing mistake: When John is in the moving ambulance with the pregnant gunshot victim, Brackett asks him if he hears fetal heart tones, and when John removes the stethoscope from his ears he leans back and we can see out the window that the ambulance is quite stationery, despite the siren.
Continuity mistake: When 51's with Cora, the woman who was thrown into the middle of a cactus patch, they lower the ladder horizontally so it's beside her for the rescue, but while Roy treks across the ladder in the next shot of Cora the ladder is nowhere to be seen, then when Roy reaches her we see that it's indeed right beside her.
Continuity mistake: When Brackett is talking to Roy and Johnny in the hallway outside treatment 3 about the guy who will likely lose his injured leg, Brackett is wearing a tie with a pattern, and when he walks into treatment 3 Brackett's tie is tied differently.
Revealing mistake: When Johnny, Marco, and Chet are all on top of Al, the big guy who has a chemically induced psychosis, while Roy injects Al with diazepam we can see the outline of the knee pad that Marco is wearing under his pants. As an aside it's funny to watch Chet's face hamming it up during this scene.
Continuity mistake: While Johnny and Roy are driving in the squad, they're dispatched to an 'unknown type rescue', and when they arrive at the incident which is a football player who kicked in his TV screen, Roy's hair is much shorter - note the front and sideburns. Then back in the squad it's the same length as earlier.
Continuity mistake: When Roy and Johnny are leaving the home of the football player who kicked in his TV screen, in the interior shot as they're walking out, Roy has a stethoscope around his neck and is holding the Biophone with his right hand and drug box with his left. In the next exterior shot, the stethoscope is gone and the drug box and Biophone have switched hands.
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.