The Bermuda Triangle, the legendary area of the Atlantic Ocean where many ships and planes have supposedly mysteriously disappeared over the years, was, as I remember, a bit of an obsession in pop culture back in the seventies. Speculation about the mysteries of the Triangle inspired countless fictional explanations in movies, TV episodes and comics. "The Time Trap" is firmly routed in that sub-genre of science fiction. The Delta Triangle is clearly an analog of the Bermuda Triangle. Writer Joyce Perry weds that real world inspiration to an intriguing science fiction premise to create one of the better episodes of Star Trek: The Animated Series.
My favorite part of the episode are the scenes showing the ruling council of Elysia. The council consists of a mix of representatives of the various races that we've seen both in past animated episodes and in the original live action series. In addition to a human and a Klingon, I could recognize an Orion, a Vulcan (or perhaps a Romulan, its not quite which he is), a Gorn, an Andorian and a Tellarite, all races seen in the original show, as well as a Phylosian and a Vendorian, from the earlier animated episodes "The Infinite Vulcan" and "The Survivor" respectively. The inclusion of what appears to be a Kzinti is a nice bit of foreshadowing, as those felinoid alien warriors wouldn't be formally introduced to viewers until "The Slaver Weapon" aired three weeks later.
The biggest flaw of the episode is that it lacks suspense. There's really never any doubt that our heroes, and our villains, will escape Elysia and that the Enterprise will avoid being blown up. It seems to me that this is mostly due to the episode's twenty-two minute run time. There is a lot of story and a lot of high concepts to fit into those few minutes. Perhaps if this had been a live action episode, and thus twice as long, these elements could have been developed more fully. Nonetheless, "The Time Trap" is still a very good and entertaining half hour of Trek. The allusions to the Bermuda Triangle mark it as very much a product of its time, yet it also has a certain timeless quality, lent to it perhaps by its futuristic setting, that allows it to hold up even forty years later.