How Many Old Ships to Take a New One?

[Jedi Master Spock]

Actually, I do mean the percentage of the power upgrade. If you get 11% of what it used to be, you're not scaling linearly - you're scaling exponentially. That's the model I'm using; it has its limits, but it seems to fit the organic situation pretty well (incremental advances all the time, each generation makes the previous generation look more or less obsolete.)

So TNG7 torpedos are 11% stronger than TNG1 torpedos, which in turn would be 11% stronger than seven years before TNG - meaning 23% stronger.

By 217 years (31 upgrade cycles and - conveniently - the length of time between ENT season 4 and TNG season 1) you're up to 1.11^31 = 25.4 times the original torpedo strength. I think that fits fairly well, especially since this should be 25x whatever the best ENT era (pre-Federation) Vulcans, Andorians, and Earthmen had to offer. TOS was 14 upgrade cycles before TNG and 17 after ENT, so we expect TOS torpedos to be 4.3 times weaker than TNG torpedos and 5.9 times stronger than ENT torpedos.

Now, if the shields were on the same upgrade cycle, we'd expect naively that a TOS ship to have 5.9x stronger shields and 5.9x stronger weapons, meaning it should be as good as a ship 5.9x as big.

The problem comes when we look at the Defiant next to the Vulcan cruiser it blew out of the water - the Vulcan cruiser's weapons and shields were both heavily outclassed. Eyeballing it, the Vulcan cruiser is around the size to match the Defiant under that model. (See here, remembering the NX is pretty much the size of a Constitution class - if I were to eyeball it, I'd say you could double the Connie in every dimension and it would be about even by volume - call that a factor of eight. ENT era non-Terran warships are pretty big.)

Now, perhaps firepower and shielding don't scale up with size with in Trek. If the strength of a shield is inversely proportional to the area of the shield bubble, for example, then by the above model, we'd expect the cruiser to have 60% more firepower and 60% less shields than the Defiant. Still not a great fit.

Alternately, if we take Yesterday's Enterprise as indicating shields improve twice as quickly as weapons instead of at the same rate (say, 22% per upgrade cycle), then we'd expect the Defiant to be typically 35 times as well shielded as something else its size and with 5.9 times the firepower.

IMO, the best model is going to be an exponential that "guesses" that shield strength is generally proportional to average dimension (i.e., ship tonnage divided by surface area, which would still give an incentive for building large ships while making them not that great) and scales accordingly for "Yesterday's Enterprise." That would give each seven year upgrade cycle 13-18% stronger shields (best guess 17%) and 11% stronger weapons.

In other words, I expect TOS shields to be 5.5-10.1 (9.0) times weaker than TNG shields and 8.0-16.7 (14.4) times stronger than ENT shields, while the weapons are 4.3x weaker and 5.9x stronger. Voyager/DS9 are one cycle further (4.8x weapons, 10.5x stronger shields.)

Nemesis is one generation further, so expect the E-E after its pre-NEM upgrade cycle to have 31x stronger weapons and 178x the shields of ENT era warships of comparable size (e.g., the Vulcan cruisers), neglecting the introduction of new weapon types (i.e., quantum torpedos).

That's my model, and I think it fits fairly well. The only problem is that sometimes ENT seems even weaker, but we should keep in mind that we should actually be comparing ENT era Klingon, Vulcan, and Andorian ships - not the experimental pre-Federation tech-transfer NX class, which is overall a bit less advanced than its fellows, IMO, especially at first.

(The choice of seven year upgrade cycles might not be arbitrary, and may have been transferred along with military technology from the Vulcan fleet.)

[2046]

The only problem with the YE info is that, much like IaMD, it occurs in an alternate timeline.

While I'm sure the real E-D had shields that were superior to the E-C, the fact is that an awful lot of tech advancement comes largely as a result of war. And war is one thing the Federation of our timeline had not really known for "decades" before 2351. Possibly since the Tomed Incident of 2311ish (IIRC).

Then came the "Taming of the West" when the Federation was challenged on multiple fronts, with the Cardassian conflict of 2358-2362, the Federation-Tzenkethi War of around the same time period, the border skirmishes with the Talarians, and so on.

But none of these seems to have been the sort of protracted, life-or-death campaign that we saw in the Dominion War, when the whole Federation . . . nay, the whole Quadrant . . . was truly in the struggle. None were even significant enough to make Starfleet build a warship, like the Borg were.

I thus rather doubt that the real timeline would've featured quite so many enhancements of shield technology as we saw with the alternate Enterprise-D.

However, that same reasoning is why I suspect that the NX Class starships of the IaMD timeline were probably bigger-and-badder-assed than the normal NX Class. But, I'd also suspect that the Vulcan, Andorian, and Tellarite vessels are somewhat weaker than their 'real'-universe counterparts.

[Jedi Master Spock]

I thus rather doubt that the real timeline would've featured quite so many enhancements of shield technology as we saw with the alternate Enterprise-D.

IMO, the motivation must be balanced against the resources. The alternate timeline in question saw the Federation shrinking as a result of a hot war with the Klingon Empire (the UFP in the "real" timeline outgrew the Klingons), and as a result, the "real" timeline may have actually had more research funding.

You can argue it any way you like it from YE alone - but I see a pretty good line of evidence for increasing durability over time relative to firepower. As time moved on, it became rarer and rarer to see a ship drop in one salvo. The E-E ran out(!) of torpedos on the Scimitar. That didn't used to happen.

Unfortunately, the YE figures are the only ones I'm really aware of comparing shielding over time - and they can be interpreted many different ways even taken as a best guess that shouldn't be too far off from the real timeline.

However, that same reasoning is why I suspect that the NX Class starships of the IaMD timeline were probably bigger-and-badder-assed than the normal NX Class. But, I'd also suspect that the Vulcan, Andorian, and Tellarite vessels are somewhat weaker than their 'real'-universe counterparts.

The mirror NX class has to be a lot nastier than the real NX class in order to measure up to the other ships. Pure offense and defense, jack for science and exploration. At the same time, though, it doesn't look any bigger relative to the Andorian and Vulcan ships, and the scaling is right for the Defiant vs the Vulcan ship...

... and I have trouble believing anyone is nicer and less well armed in the Mirror Universe.

[Mr. Oragahn]

IMO, the motivation must be balanced against the resources. The alternate timeline in question saw the Federation shrinking as a result of a hot war with the Klingon Empire (the UFP in the "real" timeline outgrew the Klingons), and as a result, the "real" timeline may have actually had more research funding.

All depends how those "fundings" are managed during a time of war. The Federation might have gone through some kind of immense nationalization phenomenom, and above all, due to the nature of business in Trek, all researches and advances geared towards military assets wouldn't be as expensive as they would in a future timeline where the business model is still extremely close to ours.

By the way, more fundings for research doesn't necessarily equal enough of those fundings even thrown into anything weaponry and defenses related.

It's quite logical that a given group, at times of relative peace, is far less likely to focus its science on weapons and defenses.

As for the rest, it's the trouble of any data from an altverse. You just don't know all the necessary details and the past and future evolution of events in it. Even if they look close enough, for any subtle reason, a given system could easily vary drastically from the inside, especially if it's superficially brushed by observers.