Revealing mistake: When Station 51 is dispatched to the bomb threat, just as they roll up on scene, in this specific POV the corner edges of the screen are blacked out due to the lens that was used, but when it cuts to other angles it's gone, then it reappears with that POV. We see it three times.
Revealing mistake: After Station 51 is dispatched to the 'plane in trouble' it becomes a plane crash rescue and recovery, and when they pull out the pilot's body, who they said died on impact, his right hand moves to clasp his left wrist, and he also bends and moves his leg.
Revealing mistake: At the apartment complex fire, after Johnny is knocked unconscious by the explosion, when the Pasadena fireman finds him and has to lift him up, it's funny how even though Johnny's unconscious we can see that he actually helps to stand himself up, so the fireman can lift him up and carry him out.
Revealing mistake: At the apartment complex where the jet fighter had crashed there's an explosion, and when one of the firefighters becomes engulfed in flames his helmet falls off, and the special fireproof headpiece that the stuntman is wearing is visible.
Revealing mistake: When Johnny and Roy are crawling on the balcony, during the fire at the apartment complex, when they pass under a window we can see the FX tubes from which the flames shoot out.
Revealing mistake: After Station 51 is dispatched to the 'plane crash into a structure', when Engine 51 pulls over to lay the dual lines at the hydrant, we can see up the block on the left, the back side of the apartment complex where they are headed, and most of the back windows are boarded up. The following scene takes place at the front doors of those apartments, where people supposedly live. The show used some real locations (not just Universal's sets) where there had been real fires, to film carefully controlled fire scenes.
Revealing mistake: During the fire at the apartment complex, there are strips of black material nailed to the tops of windows where the FX fire shoots out from below, and the doorway Roy passes when he's pulling on the hose has a fake ceiling and wall nailed directly into the door jamb, to control the strip of FX fire at the side.
Revealing mistake: At the apartment complex fire, just as Chet climbs the ladder and Marco holds the top of the ladder on the second floor balcony, we see the plumes of FX smoke spurting from the side inside the doorway behind them, and even see something quickly fanning the smoke.
Revealing mistake: At the start of the episode, we see Squad 51 speeding toward their destination, and when the camera cuts to the woman in front of the market, she's waving her arms to the squad somewhere in the distance. But notice that while Rosa is looking to her left and waving, we can see Squad 51's reflection in the window (with the liquor bottles), as they are parked right there, just off-screen waiting for their cue to "speedily" pull up.
Revealing mistake: When the Bengal tiger is on the roof, just after the officer warns, "If that cat tries to leave this roof, he's dead before he hits the street," there is a closeup of the tiger and the empty landing below the billboard. A few shots later, after Les steps on the glass, there are pieces of meat scattered on the landing below the billboard, so the trained tiger will jump onto it.
Revealing mistake: After Johnny joins Roy in the ambulance and the patient flatlines they continue to Rampart, and when Brackett asks 51 for a strip, if we look out the window that's beside Johnny, we can see GlamourTrams in the distance. And when Roy says, "Isopeterenol drip, 10-4," we can see GlamourTrams right outside the window. They are driving around Universal's lot while shooting the footage inside the ambulance.
Revealing mistake: When Station 51 is dispatched to 'man trapped', just as Engine 51 rolls out of the apparatus bay and heads down the driveway, the real 127's vehicle is seen parked inside the bay, near the rear door.
Revealing mistake: After the MI patient from the construction site is brought to treatment 1, when Early uses the laryngoscope for an endotracheal intubation, we can see that he merely places the laryngoscope at the side of the man's face, especially since we can still see the entire distal end beside the man's neck.
Revealing mistake: When Engine 8 rolls up on scene at the warehouse fire, as it passes the camera in the overhead shot we can see the real company number 60 printed on the surface between the jumpseats.
Revealing mistake: When Station 51 responds to the traffic accident, after Captain Stanley hands Johnny the Ajax tool, in the closeup it's obvious that the hands are not really Johnny's. Then there's another shot of the real Johnny, but once he removes his goggles, interestingly it's the stunt double who's in the following shots by the car, even when Johnny cuts himself, it's the stunt double.
Revealing mistake: At the house fire, after Roy and Johnny go upstairs to rescue the invalid woman, Captain Stanley and Chet head to the front door, and just before Cap kicks in the front door, we can see that the door isn't actually closed, it's just ajar.
Involvement - S5-E19
Revealing mistake: The former head nurse is supposed to be unconscious when she's picked up from the couch. Yet she puts her hand up on a shoulder when being carried out.
Above and Beyond... Nearly - S5-E20
Revealing mistake: Dixie and Brackett rush onto the elevator with a crash cart to go up to the third floor, for a possible MI in the dental clinic. The camera's POV is from the elevator, and in one continuous shot, without cutting away, we see the ER hallway through the open doors, then the doors close and in a few moments the doors open on the third floor. Even though the set has changed a bit, we can tell it's still the ER hallway by things such as the same scuff marks on the floor, and we can also catch a glimpse of the paramedic status board on the wall, where the base station room is located.
Above and Beyond... Nearly - S5-E20
Revealing mistake: When Roy and Johnny are on the cliff loading the unconscious victim onto the stokes, as they try to lift each of the victim's legs, we can see the unconscious man also lifting his own leg to assist the actors.
The Tycoons - S5-E23
Revealing mistake: After Roy and Johnny get to the hospital with the 18 month old baby who stopped breathing, when Johnny is rushing up the hallway giving mouth-to-mouth to the baby, we can see that the happy little baby is wide awake and even smiling.
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.