from Starship Recognition - Series 1: Lawrence Miller and The Daystrom Institute Technical Library - 2005

Notes - circa 2288:

     One of the earliest class of specialized Federation starship, the Tokyo class was originally envisioned as a long range scout. Part of the on-going fleet expansion begun during the Great Awakening, the Tokyo was equipped with a roomy interior, several small labs and a unique engineering hull that was built exclusively for the class. With little need for weaponry, the initial design was planned to take its place alongside the Hermes and Nelson scouts.
     Far sighted leaders had other plans for the light design. Even as the fleet continued to expand both its military and exploration divisions, fleet planners felt that a dedicated escort would free up other vessels to help patrol the expanding frontier. Tooling on the Tokyo class was halted and design changes were quietly issued in mid 2246. Designers changed the main drive to the more reliable FWD-1, deciding on the PB-47 model 2 design plans. While the model 2 required a larger plasma transfer system, it was considered safer during combat. The model 2 also required a larger engineering section which forced the removal of two labs placed in the small secondary hull.
     To ensure funding, the vessel was re-designated an escort destroyer, with a mission profile of escorting exploration vessels. A single forward accelerator cannon was mounted to ensure the vessel could drive off larger opponents during battle. When launched, the Tokyo was considered well armed, despite its lighter laser weapons. During its first four years of service, the Tokyo class proved effective in deterring pirate vessels.
     But the tides of war were soon upon the Federation. The Tokyo class, like many vessels of the era, was considered underpowered, even when compared to other destroyers of the day. The light computer, which made the Tokyo attractive to expense-minded bureaucrats, was insufficient for expansion. In late 2250, plans for a Mk II were in the works. When two Tokyo class destroyers were lost in the opening battles of the Four Years, funding for the remaining 18 vessels was cancelled. Four Mk II’s currently in the works were funded to completion, as was the updating of the remaining 10 Mk I’s. By 2253, the four new Mk II’s had been assigned to the Zone of Transport Escort, and three of the Mk I’s were nearing completion of their upgrades. Despite its power hungry nature, the Mk II’s used the larger FAC-3 rather than waiting for production of the new photon torpedo. Even with the loss of a third Mk I and the disappearance of yet a fourth vessel, the Mk II saw few other design changes. All but one of the MK II’s were assigned to escort duty, where they successfully drove off wave after wave of enemy attacks.
     By wars end, only three Tokyo’s remained. Needing few light vessels, plans for expansion of the Tokyo class were dropped from 25 hulls to only 5. The Mk III was finally commissioned in early 2261 and was sent to patrol the Orion boarders, where their improved PB-47 model 3 warp drive allowed the light vessel to directly engage pirate vessels who could no longer use the war as a cover for their operations. The Mk III also saw a significant jump in firepower when the FP-1 replaced the less efficient FAC-3. Although not as powerful as the FAC-3, the Awalt version of the FP-1 was more accurate and longer ranged. Coupled with a better sensor system and more powerful shields, the Tokyo class served admirably until 2272, when the vessels light weapons and basic design were quickly being outclassed by both Romulan and Klingon designs. The final Tokyo vessel was retired in 2274.
     Of the 21 Tokyo’s built, one Mk I and two Mk II’s are listed as missing. 3 Mk I’s were destroyed during the Four Years Was, as were 3 Mk II’s. One Mk II was destroyed near the Triangle by unknown forces suspected to be Romulans. One each of the Mk I and Mk II models were scrapped, both after combat with pirate forces. One Mk I was captured during the war. Three Mk II’s were eventually upgraded to the Mk III configuration. The remaining 8 Mk III are in reserve fleets at Rixis and Qualor II.