design by Christopher Cornelius
NOTES:
Known Sphere Of Operation: Empire-wide use
Data Reliability: C for D-21A, D-21B & D-21C models; B for D-21D & D-21E models
Major Data Source: Klingon Sector Intelligence
On 2285, as the Empire continued to push it boarders against the Romulans and the Federation, it was decided to produce a new kind of ship to help push the boarders out. In 2286, it was decided to produce a new kind of vessel, the D-21 D’Ktahg class of attack cruiser, named for the honorary blade carried by most Klingon warriors. But the D-21 would see dismal failure as an attack vessel, when serious flaws in systems became apparent. By the end of it’s first year of production, three A models had been destroyed and one scrapped, after overzealous Klingon captains had engaged Romulan and Federation heavy cruisers with superior ranged weapons. It was found the D’ktahg was lacking something and it was a rear firing torpedo and improved shields, along with other ship systems. When these problems were fixed the vessel was to take a new variant and it was decided to produce the B version with the corrections.
By 2288, the B variant had been launched, and was immediately a success. Soon afterward, the Romulans became extremely interested in the D-21 as a medium cruiser. In mid 2293, the Romulans launched a large task force with the single purpose to capture a squadron of D-21s. Although the initial attack by the Romulans had proved damaging to the Klingon vessels, the close in nature of capture operations became the Romulans undoing. As the Romulan vessels closed with the damaged D’Ktahg’s the Klingons turned and fired their weapons. The Romulans had not counted on the aft firing torpedoes. By the end of the battle, the Romulans had lost two Whitewinds, with two others severely damaged, and three Bright One destroyers. Although one D-21 was destroyed, two others were finally captured. The battle caused quite a stir in the Romulan high command, and the loss of the small fleet gave the Klingons a tactical advantage for nearly four months.
Although originally intended to be mass produced, the destruction of Praxis effected the D-21 like so many other ship designs in the Klingon inventory. Production of the A and B model was severely reduced, with only one or two new hulls coming off the assembly line per year. In 2302, the last D-21A was commissioned. Only continued pressure from the Romulans and Cardassians kept the D-21 in production. In 2312, designers presented an updated variant, the D-21C to replace the now aging D-21A and D-21B. Intended as pure refit, designers were surprised when an order for 100 new hulls was issued. The D-21C began production in 2314.
Unlike the A and B models, the D-21C returned to using the KWC power plant. Although not nearly as fuel efficient at the KWF system, the KWC was far older and more reliable, requiring less continued monitoring during operations. This allowed the refit of the primary weapon system as well as an increase in the defensive shields. The C model would also be the primary refit variant of all remaining A and B models. Despite an initial order for 100 of these capable vessels, only 40 were produced before the order was cancelled. Unconfirmed reports indicate that the House Jurris was punished for some unknown transgression.
In 2338, production of the new D-21D was approved. Rush orders for 20 of these were issued even as cancellation of the C model was initiated. The D model saw the obligatory increase in weapons and components, but also saw the first use of the KSX quad-inducer shield system. That gave ship commanders a significant amount of additional power to the weapon systems during combat. While The KSX was expensive and difficult to repair once damaged, it’s popularity meant the D-21 would go on to serve well into the late 2380’s.
The final variant to be fielded was the D-21E. The E models increased most of the on-board system and became a popular front-line patrol cruiser. The E saw extensive combat during the short-lived Federation-Klingon war initiated by the Changelings. It also saw extensive use during the Dominion war.
Of the 155 D-21s built, 5 are listed as missing (2 As, 1 C and 2 Es), including 3 that are believed in use by the IKS. 44 have been destroyed (5 As, 2 Bs, 4 Cs, 2 Ds and 31 Es). 14 have been scrapped (1 A, 2 Cs and 11 Es) and 6 have been captured (1 B by the Federation, 1 B by the Romulans, 3 Es by Dominion forces and 1 E by Cardassian forces.) 2 Ds were sold to private interests in the Triangle. 10 Cs and 69 Es are in reserve fleets and 5 Ds are in service to Ranking Families in the Empire. 53 As and 34 Bs were converted to C models. 110 Cs were converted to Ds and 117 Ds were eventually converted to E models.
The vessel was produced at the Jurris Industrial Inc. Yard 2 of Fonwal.