The Oberth Class was a very atypical design for Federation starships of the time. The Oberth Classes interior bulkheads were designed with a Victrium alloy to better facilitate it’s shielding and allow this class of ship to withstand gravitational wavefronts. Having only 1 forward phaser bank, some later designs would see an inclusion of both a port and starboard phaser emitter, and a single photon torpedo launcher.
Capable of a standard cruising speed of Warp factor 5 and a maximum of Warp factor 6, the Oberth Class weren’t exactly the fastest ships in the fleet, and later Warp Core technological improvements would see this class begin to be phased out in favour for the newer Nova Class of Starship which could achieve greater speeds at a lesser power cost thanks to its design shape and warp field refinements. Standing at about 120 meters and height at about 25 meters, this class contained 13 decks including the secondary hull.
(Paramount) U.S.S. Grissom (NCC-638) – “Star Trek III: The Search For Spock”