Sealab 2021 - Vanishing Power Line
In the episode of Sealab 2021 where Capt. Murphy wants to start a pirate radio station, he goes down to see Ted (from accounting). He tells him to launch the emergency radio beacon and when he does, the beacon has a long cord connecting it to Sealab but as it breaks surface, it pops completely out of the water and you can plainly see the cord has vanished.
on 01-17-2002 and