As we all know, the writers guides for TOS and
The Making of Star Trek gave a semi canonical warp formula for starship speeds a t various warp factors.
The speed of a starship would equal the speed of light multiplied by the TOS era warp factor cubed.
Warp factor one,equals the speed of light.
Warp factor two, the maximum speed of a freighter according to "A Private Little War", equals 8 times the speed of light.
Warp factor three equals 27 times the speed of light.
Warp factor four equals 64 times the speed of light
Warp factor five equals 125 times the speed of light
Warp factor six, the maximum safe speed of the Enterprise, equals 216 times the speed of light
Warp factor seven equals 343 times the speed of light
Warp factor eight, the maximum emergency speed of the Enterprise, equals 512 times the speed of light
Warp factor nine equals 729 times the speed of light.
And so on.
In some episodes starships seemed to travel no faster than the warp formula indicated.
In "Who Mourns for Adonais?" On the planet Pollux IV Kirk says:
KIRK: On you, Lieutenant! Reject him, and we have a chance to save ourselves. Accept him, and you condemn all of us to slavery, nothing less than slavery. We might never get help this far out. Or perhaps the thought of spending an eternity bending knee and tending sheep appeals to you.
So Kirk think that Pollux would be a long way for a rescue mission to come looking for them. Pollux is only about 33.8 light years from Earth. At warp factor one it would take 33.8 years for a ship from Earth to reach Pollux, at warp factor two it would take about 4.225 years for a ship from Earth to reach Pollux, at warp factor three it would take about 1.25 years, at warp factor five it would take about 0.52 years, at warp factor five it would take about 0.27 years (98.76 days) at warp factor six it would take about 0.156 years (56.9 days), at warp factor seven it would take about 0.098 years (35.99 days) and at warp factor eight it would take about 0.066 years (24.106 days).
So the way Kirk emphasizes how far they are from help, it doesn't seem like Kirk expects any hypothetical rescue ships to come, if at all, much faster than the TOS warp formula indicates.
In "This Side of Paradise"" Kirk & a landing party beam down to Omicron Ceti III:
KIRK: Another dream that failed. There's nothing sadder. It took these people a year to make the trip from Earth. They came all that way and died.
ELIAS: Hardly that, sir. Welcome to Omicron Ceti Three. I'm Elias Sandoval.
If "a year" equals 0.5 to 2.0 Earth years, and if Omicron Ceti is Mira or Omicron Ceti, which was believed to be about 220 light years from Earth, but is nwo believed to be about 299 light years from Earth, it is simple to calculate the average speed of the voyage. The average speed of the voyage should have been between 110 times the speed of light and 598 times the speed of light.
If the transport ship was limited to warp factor two, the maximum speed of a freighter, it would have traveled 13.75 to 74.75 times as fast as it should have. If the transport ship traveled as fast as warp factor six, the maximum safe speed of the Enterprise, it would have traveled 0.509 to 2.768 times as fast as it should have.
So the transport ship could have traveled many times as fast as the official TOS warp formula if it traveled a low warp, but if it traveled at a high warp factor like warp 6 it didn't have to exceed the official TOS warp formula.
So there are some TOS episodes where spaceships seem to travel at about the official TOS warp formula speeds, and others where spaceships don't have to travel any faster than a few tens of times the official TOS warp formula.
Bu there are other TOS episodes where spaceships travel at speeds of thousands of times the official TOS warp formula.
In "Arena" Kirk finds that aliens have destroyed the outpost on Cestus III. Before beaming back to the Enterprise Kirk orders:
KIRK: I want a search party of thirty medical personnel beamed down immediately to search for survivors. Notify the transporter room. Lock onto us. We're beaming up.
Then the Enterprise begins to pursue the alien ship:
SULU [OC]: Sulu here, sir.
KIRK: Is the alien still making warp five?
SULU [OC]: Affirmative, sir.
KIRK: Initiate warp six.
SULU [OC]: Affirmative, sir.
An unspecified time later:
KIRK: Mister DePaul.
DEPAUL: Yes, sir.
KIRK: Position.
DEPAUL: Twenty two point three parsecs beyond latest chart limit, sir.
KIRK: All scanners lock into computer banks. I want a complete record of this. Mister Spock, what do we have on this general area?
SPOCK: Virtually nothing, Captain. No records of any explorations. There are rumours of certain strange signals on subspace channels. However, none has ever been recorded.
KIRK: Anything on intelligent life forms?
SPOCK: Nothing specific, Captain. Unscientific rumours only. More like space legends.
KIRK: Mister Sulu, status, alien vessel.
SULU: They must be aware we're after them, sir. They've gone to warp six also.
KIRK: Warp factor seven.
During that unspecified length of time the Enterprise has traveled from Cestus III to the limit of their charts and then 22.3 parsecs beyond that limit. 22.3 parsecs equals 72.73287 light years, or 26,565.68 light days, or 637,576.32 light hours. So if the Enterprise traveled at least 22.3 parsecs in what seems to be a short time, perhaps between 1 hour and one day, the speed of the Enterprise would be at least between 26,565.68 and 637,576.32 times the speed of light, and thus at least between 122.98925 and 2,951.7422 times the speed of warp factor six according to the official TOS warp formula.
Later, the Metrons transport the Enterprise far from Metron space:
SULU: Captain.
KIRK: Mister Sulu.
SULU: It's impossible, but there's Sirius over there when it should be here. And Canopus. And Arcanis. We're. All of a sudden, we're clear across the galaxy, five hundred parsecs from where we are I mean, were. I mean
KIRK: Don't try and figure it out, Mister Sulu. Just plot a course for us back to Cestus Three.
SULU: Aye, aye, sir.
So now Kirk wants to return to Cestus III, which should be five hundred Parsecs (plus or minus a few tens of light years) from where they are now. Kirk knows that the medical personnel on Cestus III can survive for only a short time on their own.
So a few minutes later:
KIRK: I don't. Not anymore. And maybe in a thousand years or so, we'll be able to prove it. Never mind, Mister Spock. It doesn't make much sense to me either. Take us back to where we're supposed to be, Mister Sulu. Warp factor one.
SULU: Warp factor one.
So if the medical personnel and any survivors they find can survive for perhaps a day, or a week, or a month, Kirk expects to return to Cestus III before that time is up.
Five hundred parsecs is 1,630.78 light years, or about 19,569.36 light months, or 85,091.77 light weeks, or 595,642.39 light days. This indicates that the speed of the Enterprise at warp one would be 19,569.36 times the speed of light and the official TOS formula if the voyage will take one month, 85,091.77 times the speed of light and the official TOS formula if the voyage will take one week, and 595,642.39 times the speed of light and the official TOS formula if the voyage will take one day.
And there are other, similar examples.
One fan theory to explain such problems has been "Cochrane factors". Different regions of space will have different "Cochrane factors". A starship traveling at warp with a region of space will have a speed that is the official TOS warp speed for its warp factor multiplied by the "Cochrane factor" of that region of space. For example, In a region of space where the "Cochrane factor" is 2.187 a starship will travel at its warp speed multiplied by 2.187, and in a region of space where the "Cochrane factor" is 1,457 the starship will travel at its warp speed mulitpilied by 1,457, and so on.
But there are other theories to explain those problems.
In "By Any Other Name":
KIRK: What do you want?
ROJAN: Your ship, Captain Kirk. It will serve us well in the long voyage that is to come.
KIRK: Voyage? Where?
ROJAN: To your neighbouring galaxy, which you call Andromeda.
KIRK: Andromeda? Why?
ROJAN: It is our home.
And:
KIRK: What's the point of capturing my ship? Even at maximum warp, the Enterprise couldn't get to Andromeda galaxy for thousands of years.
ROJAN: Captain, we will modify its engines, in order to produce velocities far beyond the reach of your science. The journey between galaxies will take less than three hundred of your years.
Spock Fascinating. Intergalactic travel requiring only three hundred years. That is a leap far beyond anything man has yet accomplished.
The Andromeda Galaxy is about 2,540,000 light years from Earth.
If Kirk meant that the Enterprise couldn't reach Andromeda Galaxy in one thousand years, maximum warp must be less than 2,540 times the speed of light.
If Kirk meant that the Enterprise couldn't reach Andromeda Galaxy in two thousand years, maximum warp must be less than 1,270 times the speed of light.
If Kirk meant that the Enterprise couldn't reach Andromeda Galaxy in three thousand years, maximum warp must be less than 846.666 times the speed of light.
If Kirk meant that the Enterprise couldn't reach Andromeda Galaxy in four thousand years, maximum warp must be less than 635 times the speed of light.
If Kirk meant that the Enterprise couldn't reach Andromeda Galaxy in five thousand years, maximum warp must be less than 508 times the speed of light, and that is less than the Enterprise's official maximum emergency speed of Warp factor 8, 512 times the speed of light.
And so on. At warp factor 6, the Enterprise's official maximum safe cruising speed of 216 times the speed of light, it would take 11,759.259 years to reach the Andromeda Galaxy from Earth.
If "less than three hundred years" means between 250 and 300 years, the Kelvin modified Enterprise would travel at 8,466.6666 to 10,160 times the speed of light or about warp factor 20.4 to 21.6.
Spock says:
Intergalactic travel requiring only three hundred years. That is a leap far beyond anything man has yet accomplished.
If Spock means that no man made ships have ever traveled fast enough to reach the Andromeda Galaxy in only 300 years, and thus at about 8,466.666 times the speed of light, that would strongly imply that the Enterprise never reached speeds of 8,466.666 or more times the speed of light in any previous episode.
So that would strongly imply that starships do not attain speeds of 8,466.6666 times the speed of light, or higher, by taking advantage of the "Cochrane factors" in some regions of space to multiply their warp speeds.
And that would limply that every time the Enterprise appear to reach speeds that were thousands of times the speed of light, it actually did not. Instead the Enterprsie reached its destinations in travel times equivalent to travelling thousands of times as fast as light, without actually reaching speeds thousands of times that of light, using something totally different from"Cochrane factors".