The sidewall was the main passive protection of a warship against all sorts of weapons fire.
Technical function Edit
The sidewall was a barrier of gravitic distortion, powered by the sidewall generator, attenuating any energy attack that came through. It was similar to the impeller wedge, but unlike the wedge, the sidewall generators were incapable of distorting space enough to make a ship invulnerable to attack.
While sidewalls were used to cover the flanks of an impeller drive vessel, certain large immobile installations such as shipyards and fortresses had a full spherical "sidewall" which covered it from all angles. The sidewalls could be penetrated by missiles with penetration aides, but that required a powerful energy source at a short range. (HH1)
Bow Sidewall Edit
Developed to protect the Shrike-class LACs when they "crossed their T" in order to fire their grasers at enemy ships, and later adapted for Medusa-class podnoughts, the sidewall could be projected forward of a ship, but in doing so prevented the impeller wedges of a ship from providing any acceleration. (HH8, HH9)
Two-stage Bow Sidewall Edit
Two-stage bow walls were developed for the Edward Saganami-C-class of heavy cruiser. The first stage was a much smaller wall, that didn't link the two wedges, so a ship could still accelerate. However, the first stage was vulnerable to beams from acute angles, and missiles could even slip past it before detonating, since the "wall" was a circle only twice as wide as the ship's maximum beam. However, against a single opponent, it afforded the full strength of a sidewall, while still allowing maximum acceleration. The second stage was the full-sized bow wall, with no openings through which a weapon could easily penetrate. The second stage cut acceleration to zero, since it linked both impeller wedges. (SI1)
Stern Sidewall Edit
Stern sidewalls were also developed. Like bow sidewalls, raising a ship's stern wall prevented that ship from accelerating using its impellers for as long as the stern wall was up.
Due to the nature of the Impeller wedge, only a bow wall or a stern wall could exist on a ship at any given time (never both at once). Thus, on smaller ships such as the Ferret-class LAC, they were powered by the same capacitors as the bow wall. (HH9)