Continuity mistake: After Roy finds Willy, when he calls Captain Stanley to help get Willy out, Roy's on Willy's left and Captain Stanley's on his right as they rush out, but in the next shot they've switched, Captain Stanley is now on Willy's left and Roy's on his right, just before the explosion.
Continuity mistake: When Karen is assigned to ride along with Squad 51, once they leave the station, en route to the incidents there are only two people seated in the squad instead of three.
Continuity mistake: When Squad 51 is dispatched to 'man down', as the squad heads out of the apparatus bay, the engine we see parked in the bay is the old Crown from seasons 1 and 2, instead of their current Ward LaFrance.
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.
Pressure 165 - S5-E7
Continuity mistake: At the decompression chamber on Catalina Island, after John and Roy introduce themselves to Dr. Scott, the doctor removes the stethoscope from around his neck and puts it down, but in his closeup it's still around his neck, then in the wide shot it's gone, only to return in closeup again.
Visible crew/equipment: After Brackett tells Donny's mother that her son does not have meningitis, it cuts to an exterior shot of Roy and John driving in the squad, and the moving shadow of the filming vehicle is visible on the ground, in front of the squad.
Continuity mistake: Dispatched to the structure fire are Station 51, Engine 36, Engine 116, and Truck 3. While Johnny and Roy are searching the rooms for the young girl, it cuts to a shot of guys from 9, and later there are also shots of 28's and 19's guys, even though none of their companies were called to this incident. These are shots from previous episodes including 3x7, "Promotion."
The Lighter-Than-Air Man - S5-E8
Visible crew/equipment: When the trailer that's on fire pulls up to the front of the station, the outline of the mic transmitter is visible on the back of the woman's blouse.
The Lighter-Than-Air Man - S5-E8
Continuity mistake: When Station 51 is dispatched to the truck fire, as Captain Stanley responds to the dispatcher Roy and Johnny get into the squad, but we see Marco, Mike and Chet head back to the kitchen instead of getting on the engine, then we see both the engine and squad responding to the incident.
Character mistake: When the guy who was injured in the manhole is brought to treatment 6, he's transferred onto the ER's gurney and we see Carol taking his pulse, but then she tells Early, "Pulse 120, respiration 24," even though she never checked his respiration rate.
Visible crew/equipment: After they load Johnny into the ambulance, just as it's about to pull away the reflection of the location's array lighting is visible on the back of the ambulance.
Visible crew/equipment: When the dispatcher tells Copter 10 to meet Squad 51 at the five mile mark, Copter 10 lifts off, and we can see the moving shadow of the filming helicopter near the shadow of Copter 10.
Continuity mistake: Marco's mustache goes missing when Station 51 is dispatched to the structure fire, but then it reappears.
Visible crew/equipment: When Engine 51 and Squad 51 arrive at the training center, Captain Stanley opens the door then steps off the engine while Chet climbs down from the jumpseat, and the location's array lighting is reflected on the door's window.
Continuity mistake: During the actual rescue at Catalina Island, Johnny and Roy are now wearing water-type shoes, not their uniform shoes.
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.
Continuity mistake: After bringing the man who choked on a beer can's pull tab to Rampart, when Squad 51 returns to the station and backs up the driveway, the engine seen parked in the apparatus bay is the Crown from seasons 1 and 2, not their current Ward LaFrance engine.
The Girl on the Balance Beam - S5-E18
Visible crew/equipment: While en route to the woman trapped on a wire, the reflection of the cameraman is visible on the windshield after Mike drives past the entrance to Commercial Studios. We see it's not Captain Stanley, but instead it's someone wearing a white shirt, holding up something (presumably the camera) with both hands.
The Girl on the Balance Beam - S5-E18
Visible crew/equipment: At the gym, when Nancy wants to prove that she's feeling fine, she tries to do a cartwheel, and the outlines of the mic transmitter and wire are visible on the back of her leotard.
Continuity mistake: When Station 51 is dispatched to a structure fire (with the two girls trapped upstairs) the address given is 1911 Harper Ave, but when they reach the house with the fire, directly across the street that house number is 1637.
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.