Edward, Gordon and Henry - S1-E4
Revealing mistake: When Gordon passes a signal, the track under him wobbles.
Other mistake: When the narrator says "the conductor blew his whistle" the conductor is holding his green flag but he is not blowing his whistle.
Edward, Gordon and Henry - S1-E4
Visible crew/equipment: In the beginning shot of Gordon leaving the station, studio equipment is reflected off James' tender.
Edward, Gordon and Henry - S1-E4
Continuity mistake: When Edward arrives and tries to push the coaches. In one shot of Gordon on the siding in front of Henry, Gordon's eyes go to his left without moving.
Continuity mistake: In the shot of Thomas stopping inside Knapford with his coaches, Henry is in his new shape.
Continuity mistake: When Henry leaves the docks, there's nothing on his footplate, but when he's out of the docks, there are suddenly 2 lamps on his footplate.
Revealing mistake: When Gordon puffs into the ditch his face looks wonky and wires are visibly attached to his cab.
Visible crew/equipment: At the beginning, a camera is visible in the top right corner.
Other mistake: The narrator says "the road left the railway...", but there is a road right next to Thomas.
Tenders and Turntables - S1-E15
Visible crew/equipment: In the close-up of James spinning on the turntable a crew member's face is reflected in his paintwork.
Thomas, Terence and the Snow - S1-E13
Visible crew/equipment: In the shot after Thomas pulls out of Knapford Station, the end of the set is visible.
Visible crew/equipment: When Thomas is on the turntable, a camera shadow is visible on the left.
Other mistake: When Thomas shunts Annie and Clarabel his eyes look wonky and Annie and Clarabel are missing their names.
Visible crew/equipment: As Henry approaches the green signal, the edge of the set is seen in the distance.
Other mistake: Edward is wearing James' sad face mask when he approaches the water column.
Revealing mistake: When Gordon falls into the ditch, wires under his cab are visible.
Visible crew/equipment: When Gordon, Thomas and the express round the bend, a camera tripod is visible on the left side of the screen.
Visible crew/equipment: In a close-up of Toby, you can see a hand reflected in his left window (viewer's right).
Character mistake: The narrator says that the passengers covered their ears at the station, but no one is covering their ears, except Sir Topham Hatt.
Continuity mistake: After Thomas organized the trucks, he is facing the trucks, then suddenly he is facing away from the trucks instantly.
Answer: He was in the water.