Beam Weapon Power : Rates the strength of the phaser, disruptor, or other beam weapons carried. The figures for phaser power output are calculated with respect to the Galaxy class so as to make them internally consistent with the strength indexes. The Galaxy class numbers in turn are loosely based on (but are a little more conservative than) the numbers generated from the "Power" section (accessed via the blue button below).

Torpedo Power : Rates the strength of the torpedo armament. For Federation ships I have come up with eleven different torpedo systems, based slightly on canon but mostly on speculation - for details see the relevant entries under the "Weaponry" section. I rated each torpedo system according to how many torps it could fire per second, and ranked them against each other according to this - a key assumption being that all photon torpedoes carried by all classes are identical. Quantum torps are rated as being 2.7 times as powerful as photons - this is in line with the DS9 TM's suggestion that Quantums are rated at 50 isotons compared to the photons 18.5 isotons. However, note that the 50 isoton quantum explosion is generated by a 21.8 isoton matter-antimatter "trigger", and depending on the percentage of this energy which is used up in starting the quantum reaction, the Q-torp could have a yield up to about 70 isotons.  Also note that these figures are directly contradicted (as I once predicted that the DS9 TM quickly would be) by at least one episode of Voyager which indicates that the photons carried by that ship have a 200 isoton yield. Whatever the rights and wrongs, the torpedo power numbers on this site are now totally internally consistent.

Weapon Range / Accuracy : Attempts to rank the ships according to how well they can use the weapons they have. Basically, the rule I followed was bigger and newer ships have the room for better fire control systems than older or smaller ships.

Shield Strength : Is one of those that is ranked just according to how ships seem to fare on screen.

Hull Armour : Some of the biggest changes are here. The hull figures are now composed of several different elements - hulls can be different thickness' - light, standard or heavy, made of Monotanium, Duranium, Duranium/Tritanium alloy, Kelindide, or Variethiel, and can be single or double layered.

Monotanium was mentioned in a Voyager episode and is presumably an earlier variation on what I call the "Numberanium" type metals. I have used it for the TOS-era ships, and it counts for 5 points. Duranium is used for the TOS-movie era ships and counts for 10 points, while the Duranium/Tritanium alloy is mentioned in the TNG TM for modern ships and gets 50 points.

Kelindide is mentioned as being one of the major materials in the hull of DS9, and I have used it on all the Cardassian ships. It gets 30 points. Variethiel is an invention of my own and is the material the Dominion uses in its ships (hey, I had to call it something!); it gets 55 points. Outer and inner hull layers have been mentioned several times in TNG, justifying their inclusion. Basically, double hulls double the strength.

Hull thickness is another multiplier - light hulls divide the strength by 4, standard leave it alone, heavy double it.

Then, there is the level of Structural Integrity Field - low, standard or high. Low SIF divides hull strength by 4, high doubles it, standard leaves it alone. And no, I'm not saying that shuttles have SIF fields that make their hulls weaker than they would otherwise be - it's just a way of establishing a relationship between them, you could just as easily divide the basic material strengths down and increase these multipliers so they're all above one to give the same effect.

Extra strength can then be added for either high density or ablative armour - high density armour is another invention of mine, and basically covers any armour that isn't ablative. Ablative armour is, as we all know, used on the Defiant and other modern Fed ships. Points are added per cm of armour - 100 points per cm of HD, or 150 per cm of ablative.

All this sounds very complex, but it's basically essential if you're not going to have modern shuttles with ten times the hull strength of old battleships just because they're newer. I think the system works well, and I'm very proud of it!

Warp Speed : Is based on a direct comparison of the top speed of the class, in multiples of lightpseed. For warp factors up to 9 the formula Speed = Warp factor ^ (10/3) is used; for speeds above 9 the formula detailed on the "Warp Scales" sci-tech entry is used.

Combat Agility : This is another area that has been fairly heavily modified. You would not believe the stuff I've gone through to come up with a system that can allow shuttles very high agility without giving them absurdly high strength - it's something I've been working on for literally a year or more now! In the end, after playing with logs and god knows what else I settled on just taking the cube root of the agility number.

All of these factors are scaled so that the Galaxy class starship comes out at 1,000 in each category. This makes it easy to compare one class with another in any category - you can tell at a glance that an Akira has about one third of the shield strength but five times the agility of a Galaxy. Note that the categories do NOT relate to each other - if a ship has 1,000 in phasers and 1,000 in torpedoes it does not mean that these two weapons are of equal strength to each other, just that they are both equal to their Galaxy class equivalents.

The categories are then weighted to give an overall strength according to the formula :

The idea of this is that some factors are obviously more important than others - I know many will disagree with how much more important, but I don't think there really can be any 'right' or 'wrong' about this so I've just how weighted them according to my 'feel' of how important they are. The final (1000/1010) factor is a fudge which brings the basic Galaxies numbers down from 1,010 to 1,000. While the distribution of strengths between the various categories is pretty much my own choice, the overall strength indices mostly emerged from the consensus in the debate on RAST.

The idea of the overall strength index is that one vessel of strength 1,000 would be an even match for two vessels of strength 500, or three of strength 333 - and so on. Note that this is NOT intended to take account of factors such as the luck or skill of the crews involved.

This list applies to the Trek universe in 2375, i.e. around the time of mid Season 7 of Deep Space Nine. I have generally assumed that ships which pre-date this time have received upgrades to their major systems to bring them broadly up to date. Hence, although we have been seeing the Miranda class since the USS Reliant in Star Trek II, I assume that the Mirandas we see in modern Trek have DS9-era shields, weapons and sensors. Typically I rate such vessels as being slightly behind modern ships of equivalent size and purpose, since there is presumably a limit to how much you can do with upgrades. I have also assumed that there has been a fleet-wide programme to modify the shields of Starfleet vessels in order to make them effective against the Dominions weaponry.

Lastly, the numbers of ships. Starfleets size is a big bone of contention - not so long ago some claimed that there could be less than a hundred capital ships in the fleet, but thankfully recent DS9 eps have shown this as a nonsense. Commander Shelby indicated in "Best of Both Worlds, Part Two" that they would 'have the fleet back up in less than a year', after loosing 40 starships at Wolf 359. With a building capacity of about 60 per year and an average hull life of 100 years, a standing fleet of 6,000 could be maintained - seems reasonable. Ron Moore is on record as saying that a fleet size of 8,000 ships "seems about right", and this is the number I have gone with for the pre-war Starfleet. The numbers of specific classes are loosely - very loosely - based on the frequency we see those classes at during the show. Non-federation powers are ranked so that their fleets come out with roughly the sort of strength that I feel they have relative to the Federation.

I know this is all terribly arbitrary, but it's been fun - and frustrating - to do, and I think overall it holds up moderately well. Naturally, I'm sure you'll disagree but hey, it would be dull if we had nothing to argue about!