The Return of Wonder Woman - S2-E1
Visible crew/equipment: While the jet is flying over the Bermuda Triangle the steward releases the gas into the air, and when Steve rushes toward him in the wideshot we can see a crew member wearing jeans and a blue shirt, at the right side of the screen.
The Return of Wonder Woman - S2-E1
Continuity mistake: Quite a few of the exterior shots of the jet which Steve is on are flipped shots (including the landing closeup), note the tail number "N207L" is backwards.
Visible crew/equipment: When Joe Atkinson walks into Steve's office and comments that during WWII he "was wrapped in a cloak and carrying a dagger for the OSS," in the next shot the shadow of the boom mic is moving on the wall, at the top right corner of the screen.
The Return of Wonder Woman - S2-E1
Revealing mistake: After the steward releases the gas on the jet everyone passes out, and in the second exterior shot of the jet as it rocks from side to side, we can see the circular frame of the window from which the jet was being filmed, at the bottom right corner of the screen (this shot is flipped).
The Return of Wonder Woman - S2-E1
Revealing mistake: During the scenes on the jet with Steve and the others, before landing on Paradise Island and when the Amazon women are aboard, the end of the cabin and cockpit sets are visible at either the right or left side of the screen in some shots. (Widescreen version).
The Feminum Mystique: Part 1 - S1-E5
Plot hole: If her younger sister Drusilla is sent from Paradise Island to retrieve Diana, how did she get to Washington DC or wherever, she had no way of knowing where her older sister would be.
Fausta, the Nazi Wonder Woman - S1-E3
Continuity mistake: After Wonder Woman is kidnapped, Steve commandeers a taxicab which has damage on its roof, but when Steve is driving the cab there's a black cloth taped to its roof covering the damage.
Factual error: In the opening sequence, a man placing dynamite on the truck is dressed in a camo-type uniform. This type of clothing was not introduced until 1981, and the episode was set in World War II.
Suggested correction: The camo type/color seen was around during WWII. It should also be pointed out the mistake claims it wasn't introduced until 1981, but the real life filming occurred in 1976. So they can't have been using camo type during filming that wouldn't even be introduced for another 5 years.
Continuity mistake: Throughout the show Wonder Woman goes from wearing heeled boots to flats, most notably when she does her leaps.