The Salamis is a frigate sized at 12 studs long, and comes with 6 main guns (3 forward mounted and 3 rear mounted), 2 missile a launcher pods, 6 point defense guns, and comm antennas mounted on secondary bridges mounted on the sides of the hull.
The Salamis class's lack of speed, ability to carry frames, and relative lack of 'punch' restrict it from independent operation. Instead the class usual acts as an escort for larger capital ships where multiple frigates working together can form effective screening forces for the more important task force leaders. While between the point defense, main guns, and long range missiles the Salamis is able to engage at all ranges of ship to ship combat, traditional naval doctrine usually reserves each ship in a force to a fixed engagement envelope. By fulfilling a predetermined role the ship contributes to the overall engagement strategy more effectively than the limited crew might otherwise.
Salamis Class by
The Hydromancer, on Flickr
The Salamis Kai is a modified version of the lackluster but dependable Salamis class, and as such is also a frigate sized at 12 studs long. In order to bring the Salamis class into the modern era of frame focused combat, the Kai's forward bow has been modified to fit a hangar bay with a vertical lift elevator and topside launch catapult, necessitating the removal of one of the main guns. In order to increase the weight of the attacks the Kai could throw in medium range anti ship bombardments, the secondary bridges were replaced with duel main gun mounts, effectively increasing the total number of barrels to 9. Between the additional weapons and the widening of the bow for the hangar which also necessitated the removal of the missile pods, the Kai's role in combat is more definitely defined to medium range where it might better support the frames it launches. Finally, boosters were added to the engine to improve its overall speed.
The Kai represents a focused effort to improve the Salamis overall, but doesn't quite replace the original's role in the navy. Instead, the Kai is mostly likely to be seen serving as the lead vessel in a small task force comprised of several additional normal Salamis class ships operating in areas deemed less important or dangerous enough to warrant a true capital ship. Alternatively a ship or two of the Kai class may be attached to an existing task force to supplement the frame squads available for duty.
Salamis Kai Class by
The Hydromancer, on Flickr