Continuity mistake: At the start, when Johnny and Roy get back to the station from their run, Roy leaves two cabinet doors wide open when he gets two coffee cups, but in the next shot as he shakes Jason's hand, those two doors are suddenly closed.
Heavyweight - S3-E5
Continuity mistake: At the start, after Station 51 is dispatched to the apartment fire, when a musician asks Captain Stanley for help removing instruments from the burning building, the next shot showing Truck 98 rolling up is footage from 2x13, "Drivers", during the fire at the Atlas Hotel. We can even see the smoke through the Atlas Hotel's windows, and Squad 51 parked across the street. More footage from the Atlas Hotel fire is shown when Engine 16 rolls up. Additional footage from other episodes are shown as well, when we see helmets and rigs bearing company numbers that were not called to this fire.
Heavyweight - S3-E5
Continuity mistake: When the little boy who received an electric shock is brought into the ER, in the shot from the hallway he's taken into treatment 4, which is beside the nurses' station, but in the next shot from inside the room, we can see treatment 2 on the opposite side of the hallway, which is next door to treatment 4. This means they're actually in treatment 1, not 4.
Heavyweight - S3-E5
Continuity mistake: At the structure fire, after Roy helps the pregnant woman down the stairs, when Johnny brings the O2 and blankets for her, we see that Johnny's wearing a SCBA tank with no markings. However, after Roy tells Johnny to take off, when Johnny hurts his shoulder, his tank has two large stickers - a white and a red.
Continuity mistake: At the start, there's a long shot of the Land Rover driving down a long stretch of road towards the camera and then passing it. That road, landscape, and mountains are very distinctive. As Roy, John, and Chet continue talking and driving, when they reach the scene of a traffic accident, Chet sets up a flare behind the Land Rover and another flare behind the pickup truck, then Chet sees a car coming from the direction which the Land Rover was headed. The problem is that the road/landscape/mountains shown earlier in the long shot of the Land Rover, which had been driving from the opposite direction, is the same that's shown here, as Chet tries to stop the car. Then to top it off, when Chet first notices the second car in the distance, it's coming from the opposite direction of the first car, but once again the view is exactly the same.
Continuity mistake: When Johnny, Roy, and Chet are at the site of the traffic accident, during this scene the shadows' lengths - from long, to short, back to long, and its directions keep changing drastically. Such as when Chet stands in the middle of the road, looking in the direction of the vehicle with the siren, his long shadow is cast to his left, but the oncoming vehicle also casts a shadow to its left (even though it's heading towards Chet), then in the next shot that vehicle's shadow has moved to its opposite side.
Continuity mistake: When Johnny adjusts his IV after the snakebite, he tells Captain Stanley that he's ready to leave, and Chet is not wearing his helmet, but in the next shot as Marco heads for the squad Chet is wearing the helmet.
Continuity mistake: When Johnny is bitten by the rattlesnake he's holding the handie-talkie, but then he drops it and the HT falls to the other side of the car, as he hoists himself up against the car door. However, when he sits down on the ground he is still holding the handie-talkie.
Continuity mistake: When Station 51 is dispatched to the car over the cliff at Bear Mountain, the timeout is 08:12, then when Roy contacts Rampart his watch reads 6:55. When Johnny checks the girl who can't see, his watch reads 12:45, but when Johnny contacts Rampart his watch reads 6:05. Then after the snakebite, when the guys carry Johnny to the back of Engine 51, Johnny's watch reads 10:35.
Continuity mistake: At the scene of the traffic accident, when Johnny tries to calm the woman who cries that she's afraid, it cuts to a shot of Chet as the camera pans to the left, and we see the position of the pickup truck on the road. When they hear the siren of help coming, Chet stands in the road directing the vehicle, and the pickup is not where it was in that earlier shot, it's now much farther down the road.
Continuity mistake: At the start, there's a closeup of Roy, Johnny, and Chet, and it cuts to a long shot of the landscape around them while they're driving, then it cuts back to the closeup. The landscape the Land Rover passed in the long shot is entirely different than in the previous and following closeups.
Continuity mistake: When Roy and Chet go to Rampart to visit Johnny on their day off, Dixie tells them that Johnny's in room 205, but when Chet and Roy walk in the number on the door is 230.
Continuity mistake: When Chet flags down the young driver to get help for the traffic accident victims, the driver's side wing mirror is tilted out at a wide angle in the long shot, but in the next closeup the wing mirror has been pushed flat up against the car, so as not to block the actor during the conversation.
Continuity mistake: After Roy's had his arm bandaged in the ER, Brackett points to the treatment room Johnny's in and says he's in 4, and Roy heads there. Then after speaking to Johnny, when Roy opens the door to leave Johnny's treatment room, we can see the treatment room facing Johnny's, and it's treatment 2, which means that Johnny is actually in treatment 1, not 4. Plus the fact that the boy with the heart problem is supposed to be in treatment 1 at that time.
Continuity mistake: In the opening scene when Johnny and Roy walk into Captain Stanley's office, Johnny's pack of cigarettes is in his right shirt pocket. As he and Roy are talking in the apparatus bay, the cigarettes are still in his right shirt pocket. When Johnny enters the kitchen after Roy, the cigarette pack has magically moved to his left shirt pocket.
Continuity mistake: During the structure fire, after the security guard has been carried down the ladder, in the interior shot when Johnny follows, he places his injured right leg out the window first, but in the next exterior shot it's his left leg which is out the window, then it's back to his right leg being first out the window.
Continuity mistake: When Engine 51 gets the run in the middle of the night, the engine company rushes to the rig including Johnny, which leaves Roy standing in the dorm alone. After he shouts out to Johnny from the doorway, when Roy turns to go back into the dorm, some changes have occurred - the locker room door is now closed, there are clothes lying on Cap's bed where none were a moment ago, etc.
Continuity mistake: When Engine 51 gets the run in the middle of the night, Johnny's so tired that he stands on Engine 51's tailboard half asleep, and as it rolls out of the bay and makes a right turn, Roy shouts out to him that the run is not for them. There are two problems with this. The entire back of Engine 51 is different between the closeup and wide shot - the surface, the lights, the license plate area, etc. Also, the engine makes a right turn out of the bay, but Roy's looking out towards the left while he's shouting, as if the engine's turning left.
Continuity mistake: After the paint factory fire, when Roy and John are with the lawyer in Captain Stanley's office, Roy's chair is either directly in front of the desk or off to the side, depending On Camera angles. Their body positions change between shots as well.
Continuity mistake: When Dixie opens the door to Brackett's office, there's a pile of white papers on the desk in front of Brackett, but when he walks out of the office, in the view from the hallway, the desk lamp has moved and there are no papers where there were in the previous shot.
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.