How Many TOS Constitution Class Ships *Can* There Be?

Emperor Norton

In the episode "Tomorrow is Yesterday" Kirk mentions "only twelve like it". Traditionally, this has been treated as the absolute canon barrier for how many Constitution class starships were in service when Kirk made that statement in 2267. If we assume a similar time frame to the episode air date, this statement would have been made in January 2267. That means twelve ships total, or twelve other than the Enterprise resulting in thirteen ships. The definitive production list starting in Season 2 (after said episode) were fourteen ships:
  • Enterprise
  • Exeter
  • Excalibur
  • Lexington
  • Yorktown
  • Potemkin
  • Republic
  • Hood
  • Constitution
  • Kongo
  • Constellation
  • Farragut
  • Valiant
  • Intrepid
That indicates either one of two possibilities: one or two more ships were constructed following that episode, or this can be assumed to be all Constitution class vessels originally constructed, at least one of which had been lost as of 2267. Several of these vessels would be lost on screen following Kirk's statement. Given on screen information from the film era (I'm not sure about later series), we know that more Constitution class ships were constructed following the statement.

My question therefore is how many Constitution class ships could we logically argue could have existed during the TOS era, following that statement in 2267? The TOS era for the purposes of this discussion could end in 2270, or it could be pushed as far as 2273 when the Motion Picture is assumed to have taken place. I believe it was mentioned that the Enterprise was one of the first ships refit, so it could be inferred that ships launched between 2267 to 2268 would end their five year missions around 2272 to 2273, which is in the timetable for their own refit. I do not believe on screen information is sufficient to mention launch dates, so it makes it difficult to know how long it would take to construct and launch a vessel of the class.
Enterprise herself is already two decades old or so when Kirk mentions how many are in the fleet presently. (or if we go by the Kelvin timeline a decade or so old). It depends on just have quickly Starfleet can get them built and just how many they need, and just how many they need to replace.

If we assume they continued build this class of starship in one form or another until the Excelsior-class comes out, that makes it so more of this class keeps getting produced at some rate until at least the completion of the USS Enterprise (NCC-1701-A) ex-USS Ti-ho or Yorktown or Atlantis, or whatever. Enterprise herself (NCC-1701) was lost not too long before that and had been scheduled to be retired not long after it had been planned to put a new crew on the ship following her time as a training ship (if one can interpret McCoy's question to Kirk about just putting an experience crew back on the ship as being Enterprise was meant to go back on active duty soon). One guessed at it was decided to retire her so her name could be used on a new Excelsior-class starship, but with Kirk stole her and lost her, than required a reward ship, they renamed a Constitution as an interim ship until the now delayed Excelsiors could be built.
I don't want to delve outside the canon as much as possible. However, if we assume the time table of the Enterprise beginning construction in 2242 and launching in 2245, in addition to the refit taking roughly 2.5 years, we could infer it would take roughly 3 years from construction to launch for a Constitution class starship. I also looked into the Yorktown class navy carriers that the series based it's ideas on. The Yorktown and Enterprise took 3 to 4 years from construction to commission. The Hornet took a year between when it was "laid down" and when it was launched, and under a year from launch to commission. So we could possibly infer a similar timetable for starships: laid down, with roughly a year to launch. During the launch period, a ship is not necessarily fully built, and systems will be installed later. And then roughly a year after that for commission, when it is given to a captain. So that would line up with the 2.5 years of the Enterprise refit correlating to the amount of time it would take to build a totally new ship.

However, there are unknown variables. In naval terms, ship progress from construction to commission seems to go faster after the design has been around for a while. The 2.5 years was for essentially constructing an entirely new vessel on the body of the Enterprise. A Constitution class starship launched in 2267 compared to 2245 could therefore have it's progress go significantly faster. For argument's sake, say a year from construction to commission. On the other hand, the Constitution class vessel of 2267 would not be the same as the one of the 2240s, as it underwent refit at least by 2266. Therefore, it would be only a year or two into this design if new ships were launched in 2267 to 2268. However, this refit does not appear to have been as extreme as the 2270s refit, so perhaps we could assume ship construction and commission could work on a quick timetable nonetheless. There is also the unknown variable if Constitution class ships were under construction but not yet commissioned as of 2267. However, this is a discussion on plausibility of how many there could have been, and not necessarily how many there were.
I must also mention that for all those lovely 14 Constitution class starships chosen for the start of season 2, the production people seemed to have the same urge we do of trying to push out more. 14 does not even correspond to the "12 like it" that was stated as fact, hence why we assume one or more had an earth shattering kaboom go off on it and assume that there were 12 others like the Enterprise, and therefore 13 ships active at the time. So this is in keeping with that spirit. 14 vessels is already a lot for a capital ship in naval terms.
Ask Franz Joseph and you'll hear 120 or more Connies. I think that's steep. But if there are 20 or so, that's fine with me. There's no reason to limit our total to twelve ships in all.

I think it bears mentioning that before the 14 ships, there were two other lists that were proposed. D.C. Fontana's proposal from August 1967 included 21 ships. Of that, the following ships were not on the final list:
  • Essex
  • El Dorado
  • Excelsior
  • Saratoga
  • Hornet
  • Wasp
  • Bonhomme Richard
  • Monitor or Merrimac
  • Tori ("bird" [note: in Japanese])
  • Lafayette
  • Ari ("lion" [note: in Hebrew])
  • Krieger ("warrior" [note: in German])

Bob Justman's proposal had just 11 ships, which is keeping in line with the "Tomorrow is Yesterday" statement. Heck, it is even more conservative, as there were only 10 other Constitution class starships other than the Enterprise. Of that, the ships not on the final list are some of the ones found in Fontana's list: Essex, Hornet, Wasp and Lafayette. It is also worth mentioning that there are names on the final list which are in neither earlier proposal. All in all, neither list really has diddly to do with the canon since they were not placed into the canon. However, they are an interesting resource to mine for ideas and concepts. It seems if there were four more Constitution ships to be had if they were writing it, they would be named Essex, Hornet, Wasp and Lafayette. And it does go to the idea that they, like us, had this list but thought "Well we could add this too. And this would be cool. And how 'bout this".

Ask Franz Joseph and you'll hear 120 or more Connies. I think that's steep. But if there are 20 or so, that's fine with me. There's no reason to limit our total to twelve ships in all.


I admire Franz Joseph for the other starship classes besides the Constitution class. But I wholly disagree with the idea of subclasses and the multitude of all too many starships in a class. It is a fun area of fandom and a fun canon in it's own right, but it does not work as Star Trek canon. But I agree that 20 may be an alright number.
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I had a thought. Based on "The Case of the Jonathan Doe Starship", I would assume that the ships listed on the chart of Starbase 11 are Constitution class starships. And this supposition is going to be as lacking in basis as that article, but it has been influential on what became ship numbers in TOS-R. And this is going to be flawed and based on quick observation. So here we go.


Removing the numbers that have been assigned to Constitution class starships leaves us with the following numbers: 1831, 1864, and 1718. Greg Jein misread this as different numbers (1631 and 1664; heck, I could be misreading 18/664 myself), and in the case of 1718, this number was intended for the USS Endeavour, but this ship was later given the designation of NCC-1895 in the canon. It is therefore a free floating designation. Of these, NCC-1831 is at 100% completion, NCC-1864 is nearing 80% completion, and NCC-1718 is at 45% completion. If we assume that in this case, "complete" represents construction, and that it takes at least a year for a Constitution class to be built by this period, then this would indicate that these ships had to have begun construction in 2266. "Court Martial" was first aired in February 1967, but was filmed in October of 1966, and if episodes were aired in production order then it would have aired in December 1966 as the 14th produced episode in lieu of "Balance of Terror". Regardless, it takes place in early 2267, so we can assume sometime in January or February of 2267. So construction on NCC-1831 would have had to have taken place in January or February of 2266, NCC-1864 some months after that, and NCC-1718 several months after that. So that's three ships under construction throughout 2266, into 2267.

Assuming a year for construction of each, each should be completed in 2267, and certainly not before the latter part of the year when "Tomorrow Is Yesterday" would have taken place. Assuming a year for launch and then another year for commission, these would be three ships launched by 2268 and commissioned by 2269. Depending on timetables. I am assuming a year for launch and a year to commission, but after construction is completed, it could be considerably less. That is all assumptions based on the giant assumptions I am already making in this thesis.

So based on this theory, it is plausible for three Constitution class ships to be constructed a year, beginning in 2266. If we assume it takes two to three years from construction to commission, that would mean ships begun in 2266 would be commissioned by 2268/2269, 2267 ships would be commissioned in 2269/2270, etc. I would assume (again, in this vast sea of baseless assumption) that they would stop with TOS Constitution ships when they got to the point of the massive refit, which began in 2270 or 2271, and not make flag ships for a five year mission that were soon to be outdated. I would assume they would want them back by 2273 to 2274 at the latest. So I think it would stop at about there, making for around an additional six possible Constitution class starships in the TOS era before it is over.

And again, this is totally baseless speculation. You could drive an 18-wheeler through my logic, and easily point out something I misread or did not read. But then again, so was "The Case of the Jonathan Doe Starship".

I forgot to include the USS Eagle. Greg Jein assumes it is NCC-1685. However, it was later mentioned in canon as NCC-956. We can get into the convolution of NCC designations, but what this means is that it is another free floating number. Going by the same logic, we can assume it is a Constitution class ship under construction, which is a little over 20% completion. So that lines up with a concept of ships beginning production, one after another, with a distance of several months until production starts on the next. This also means 4 ships rather than three beginning construction in a year. And therefore, by my logic, it would be around 8 rather than around 6 Constitution class ships that could be constructed in the TOS era.

I will also amend the theory with the idea that there may not be a difference between launch and commission in Starfleet. It may be that as a ship is nearing completion or shortly after completion, a captain is assigned, chooses his crew, and the ship is commissioned. This would remove a year from the theory, and crew selection could only take a period of months if it occurs after a ship is completed rather than as a ship is nearing completion. I use the example of the Enterprise-B as the basis for this theory. The ship had a captain and crew when it launched and appeared to be commissioned. They had the space champagne and everything. However, it was missing equipment, which is the sign of a launch prior to naval commission. Therefore, launch and commission appear to be synonymous in Starfleet, or at least there is the possibility that they are. So again, this shaves off a year in the theory. Therefore, ships constructed in 2266 could be commissioned in 2267/2268, 2267 commissioned in 2268/2269. However, if ships were built beginning in 2268 and launched in 2269/2270, that would place them right in the era of the massive refit and they would return for refit only in 2274 to 2275. We could argue Starfleet would already have begun updating these ships such that they are a bridge between the original design and the advancements of the refit and the refit is easier, but that complicates the theory. I would therefore assume that it would only be only 8 ships.

Of the 14 ships in the season 2 production list, the USS Constellation was destroyed in 2267, the USS Defiant was lost in 2268, and the USS Intrepid was destroyed in 2268. The USS Farragut was never officially mentioned as destroyed, but there's indication it may have been. And for the "12 like it" statement to work, I assume the USS Valiant was destroyed prior to 2267. The USS Defiant complicates things, because it was not on the list of 14 ships. So I will set it aside for the moment. So if we assume 13 Constitution class ships, at least three of which had been lost, and add that 8, there are 18 Constitution class starships.

There is the complicating factor of the following three ships not being part of the list of 14.
USS Defiant (NCC-1764)
USS Eagle (NCC-956)
USS Endeavour (NCC-1895)
I do not know how to properly treat these three. If we just add them on, no questions asked, and with the USS Defiant lost, it would be 20 ships. Perhaps we can assume the Defiant was not yet commissioned as of that statement in 2267, and therefore would be in the pool of ships under construction.

After all that, I have a headache. There's 17 of the 12-13 Constitution class starships? Jee whiz. Someone make that logic work.
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IMHO there are planetary defense forces - separate from Starfleet and run by the federation and/or individual planetary governments - that have a lot of powerful warships as well as giant force field generators and giant phaser banks and other orbital defenses.

IMHO Starfleet has a lot of powerful warships in their defense branch forming various regional defense fleets.

IMHO opinion in "Tomorrow is Yesterday" the 12 like the Enterprise are also Constitutional class starships. IMHO Starfleet defines starships as starfleet ships with as much firepower as the best classes of starfleet defense ships and science facilities as good as the best science ships, and so on to make them top of the line in every desirable aspect of a starfleet vessel. In TOS Starfleet has many classes of ships such as survey ships, science ships, transports, cargo ships, pure warships for defense, etc. that are not classified as starships, as well as one or more classes of starships.

IMHO the plaque says starship class because the constitution class were the first class of starfleet ships to serve as starships and other classes of starships were not constructed until later, and then the Constitution class ships were renamed since they were now a sub category of the broader category of starships.

IMHO other starships seen in TOS could have been Constitution class starships or starships of other classes that looked similar to the Constitution class externally. IMHO the production staff goofed in their memos by supposing that all starships were constitution class.
For all we know, the day after Kirk made that statement, Starfeet opened a half-dozen new shipyards (the USS Defiant was built on Luna as per "In a Mirror, Darkly" and it appears the USS Discovery is launched from an asteroid base somewhere, so they weren't all out of San Francisco), each with an output of 1 starship per Earth year.