Thomas, Percy and the Coal - S2-E1
Visible crew/equipment: In the restored version, studio equipment can be seen when Toby pulls Annie and Clarabel and at the water tower near Tidmouth Station (at the top of the screen in both scenes).
Continuity mistake: Thomas appears to be damaged and dirty after his accident but in the final scene, he is undamaged and clean.
Revealing mistake: When Toby asks Thomas if he took on enough water, Toby's eyes are wonky.
Continuity mistake: James and Edward are on the mainline at first, but then they overrun the platform at Dryaw station, which is on Thomas' branch line.
Audio problem: In the 1992 "Thomas Gets Tricked" VHS release, the music stops and a man's voice says, "Look out for the train!" when Thomas climbs up Gordon's Hill. The voice can still be heard in the 1995 release, but the music does not stop.
The Sad Story of Henry - S1-E3
Revealing mistake: When the passengers try to pull Henry out of the tunnel, they have putty on their feet. Sir Topham Hatt's hand is also purple.
Continuity mistake: When James passes Edward at Vicarstown, Edward's train does not have a brake van. But two shots later, it does.
Factual error: A "wonky" whistle doesn't sound like a slide whistle, it should sound like a weakened version of the correct whistle mixed with the hissing sound of steam. A "wonky" whistle would also leak steam constantly instead of being blown like a normal whistle.
Audio problem: When Arthur arrives at the lake, he has Spencer's whistle.
Continuity mistake: When Thomas is organizing the trucks, in a second close-up of a truck, the background disappears in mid-sentence.
Edward, Gordon and Henry - S1-E4
Visible crew/equipment: When Gordon backs on to the siding, you can see the inside of his cab, which is just some equipment.
Edward, Gordon and Henry - S1-E4
Other mistake: When Gordon leaves the station, he has two brake coaches, even though express trains are suppose to have one.
Lady Hatt's Birthday Party - S5-E4
Continuity mistake: When George crashes, the Fat Controller falls into the ditch head first, but in the following shot he is sinking feet first.
Continuity mistake: The sign says: "Danger - engines must not pass this board." When Thomas passes it, "board" is replaced with "point."
Revealing mistake: In a shot of 2 vans singing "Pop Goes Old Ollie" you can see a spider crawling on the right side of the left van in the screen.
Visible crew/equipment: When Bill runs beside Boco, you can see a camera moving out of the shot. (Visible in HD full screen version).
Revealing mistake: Max's wheels can be seen moving backwards when he is actually driving forwards. Also, both Max and Monty's steering and wheel speeds are out of sync with their movements. These events happen throughout the episode.
Visible crew/equipment: When Thomas puffs away from Toby, two steam platforms are visible.
Thomas, Percy and the Squeak - S6-E21
Other mistake: When Thomas sees Percy at the washdown, Gordon's front and rear bogie wheels are derailed.
Santa's Little Engine - S17-E18
Revealing mistake: At one point, the shading effect on Thomas' whistle is not rendered properly, so it appears silver instead of gold.
Answer: Breakdown trains help the engines back on track.