"The Sky's on Fire" from Season 2 says "1978" at the beginning.

The fact that a number of episodes begin with a specific year shown in boldly at the beginning and the fact that they never use the same year and sometimes even seem to jump back in time to earlier years seems to suggest that some of the writers might have been making an inside joke, or maybe just testing to see if IA ever noticed or cared. (Obviously, IA never noticed or cared.)

As someone previously stated, the years arn't really that important. It was just supposed to convey 'this is the not so distant future'.
You also have to remember that none of the people had DVDs or video's back then so there wasn't anyone constantly viewing past episodes. (Though you'd think the writers would have had a timeline.)
He who fights and runs away, lives to run away again!

In the first series it wan't superimposed but often referred to verbally as 1973. The later series had the superimposed numbers, commonly 1978 in the second seriss. I remember after that it went as far as 1981. As a litte boy when first watching it, years like 1981 were miles in the future, or seemed like it!

The exact date given is July 14, 1978.

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I'm watching "The Deadliest Game" right now, and Crane just said "1978".
I'm just a patsy!

I'm watching And Five of Us Are Left, and a TV announcer says it's 1973.
This will be the high point of my day; it's all downhill from here.

Well, the episode "Hail to the Chief" (episode 16 of the first season) opens with a shot of a secretary writing on a desk diary dated June 24, 1973.
(Incidentally, she writes that the the helicopter on that date will be ready at 10:04. Try not to be late!)
I'm not sure Irwin Allen cared much of a fig for continuity, though

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I guess the idea was "it's the future". So to jump around the 1970's on a show that made little sense anyway doesn't really matter.
And continuity? Hah! Every time another sub was featured in an episode, the interior always looked like the Seaview. They just used the same set and said what the hell, a sub's a sub, right.

apparently time consistency wasn't big in the 60sat the beginning of each Star Trek episode the "star dates" were basically randomI've read a number of quotes from Gene Roddenberry & several of the writers that nobody kept track or cared; they just stuck numbers in.
Maybe back then they thought nobody would notice that sort of thing in those 'science fictiony' shows

Maybe they thought there could be a Submarine like that by then .

^^^The dates really mean nothing in VTTBOTS. Since season 2 had back to back episode with a two year gap. Far as Im concerned 4 years passed. I dont think the writers ever really could nail down a year when the series really took place, so each writer just made up a time frame with each episode.
Regardless it doesnt bother me. Still love the show.

For a series that ran 4 years, the action depicted supposedly takes place between 1972/3 and 1982 or 1984 depending upon episodes. I know the b&w year 1 episodes had the date of '72 or '73 being mentioned and/or superimposed over the picture. So a time-frame of approximately 10 years has elapsed for the crew of the Seaview!

I just watched the season 4 volume 2 set, and at least two episodes said "1982."
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The first season episode "Hot Line" was set on May 27th, 1973. - alpha128 (me)

I remember 1978 and later episodes said 1982. - Roving_Mob

Yes, they jumped around the '70s. - CaptGage
I recently started watching Season 2 right here on the IMDb (
http://www.imdb.com/board/10057798/episodes#season-2
) and see what you mean about jumping around the '70s. "And Five Of Us Are Left" begins on November 16, 1973, consistent with the continuity of the first season. "The Peacemaker" is set in 1978, while the very next episode, "The Silent Saboteurs" takes place two years earlier in 1976! It seems like they suddenly stopped caring about continuity.

Same for The Peacemaker.

Dead Man's Doubloons states 1978 at the beginning.

There was definitely an episode where '1978' appeared.

An episode featuring Albert Salmi started out with a fierce 16th century sea battle with pirate ships, then flashed forward to the "present" year as shown in a superimposed title: "1978." (Salmi played the pirate and his supposed descendent). Reference: Season 2, Episode 21, broadcast 13 February 1966.

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I seem to remember an episode that mentioned 1973. Even more amazing thing is, in the episode the crew are listening to a report about how the New York Mets have won the World Series! Remember, the episodes were shot in the mid-60s, when the idea of the Mets winning the World Series were about as fantastic aswell, you get the point.

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