AN OUTGROWTH OF THE OLD "D7" FIRST SEEN IN ST:TOS, this classic design does not get nearly as much screen time as the various "Bird Of Prey" Klingon ships. First featured in the ST:TOS episode "The Enterprise Incident", the D7 vessel would make two more appearances in ST:TOS, a return enagement in the opening moments of ST:TMP, yet another appearance in Star Trek II, and a final major film outing as the flagship Q'uonos One, used by Klingon Chancelor Gorkon in Star Trek VI. The K'tinga also has sundry minor appearances in ST:TNG and ST:DS9, suggesting that these venerable vessels underwent extensive refits and upgrades, making them viable over a century after they are first introduced on-screen.
        Cosmetically, we have seen several different types of this class, all with the same general shape, but different detailing.  Since the original FASA schematics came in two types, one smooth-faced and the other heavily etched with hull markings, I have consolidated the pages and their stats.
        The original D7 model from ST:TOS sets the standard for all Klingon naval designs produced afterward, just as the Constitution hull would have a major impact on future Federation ship design philosophy. With its spread-wing main hull, long neck, head-like command pod and wingtip mounted nacelles, the D7 is rather predatory in appearance, and is terrific fun to play—whether in fleets or in one-to-one action.

From the FASA Star Trek KLINGON SHIP RECOGNITION MANUAL, circa 1985
D-7 (Various Names) Class IX-X Cruiser
Known Sphere Of Operation: Empire-wide use
Data Reliability: A (all models but D-7S); D for D-7S
Major Data Source: All models in Star Fleet possession; Klingon Sector Intelligence.
The D-7 is probably the most infamous cruiser ever to stalk the spacelanes. These ships are associated with death and destruction on a scale second to none. When first introduced, these vessels captured the minds and spirits of the Klingon commanders so fully that for many years they were the symbol of Klingon tyranny.
       This design was developed from the earlier D-4 cruiser and incorporated all of its most popular features. The command pod mounted forward on the boom assembly and the wing-like main hull were changed slightly in the design, but all of the basic concepts were retained. In all models, the command pod can be jettisoned in case of emergency. A small micro-impulse drive system, mounted into the pod just for such emergencies, allows the pod to maneuver itself and travel short distances in hopes of rescue. A pod can maintain the life-support systems and operate the short-range sensors and weapons for up to one year. One of the main features of the pod is the disruptors mounted below the bridge; these weapons will give protection from hostiles and also allow for the self-destruction of the pod if capture is imminent.
       The secondary bridge, weapons control, and all engineering facilities are located in the main hull. Separated from the command pod, this section of the vessel is capable of maintaining fully functional life-support, weapons, and engine systems for up to two years. Of course, this section is capable of warp speeds and will effect its own rescue much quicker than can the command pod. Within the engineering section of the main hull are the matter/anti-matter mix chambers, little shielded, as servitor races man the engineering compartments of most Klingon vessels. All D-7 models are capable of jettisoning the warp engines in case of an uncontrolled mix in the matter/anti-matter chamber. This would leave the ship with only the impulse engines for power. In most cases where warp engines have had to be ejected, the command pod has been separated first to insure the captain will be safe.
       In the center section of the main hull are compartments containing hypothermia capsules for the marines. The troops are kept in a frozen state until they are required, which reduces the requirement for food and life-support and thus prolongs the on-station time of the ship.
       Introduced on Stardate 1/8611, the D-7A didn't see any action in the Unknown War, but the lessons learned from this conflict were reflected in its design. By Stardate 1/9302, eight separate manufacturing facilities were producing this model at a rate of five per month. When the Four Years War broke out, production of these ships soared to twelve per month within the first year and peaked at 26 per month by the third year. The Klingons, having brought the war on, were ready with over 400 of these ships in the front-line; studies have shown that this numerical advantage was the prime factor in their early advances into Federation territory. On a one-to-one basis, Federation cruisers and frigates were far superior as warships, but their limited numbers prevented them from turning the Klingons back in the early stages of the war. The D-7A class, named "Painbringer" from the Klingon K’tagga, served the Klingon Imperial Navy well in the war with a high reliability rating and ease of repairs.
       Of the 1,671 D-7As produced, 431 remain in active service, 83 have been placed in reserve fleets, 12 are used by the Klingon Naval Academy as training vessels, 891 have been destroyed, 23 have been captured (10 by Star Fleet, and 13 by the Romulans) 15 are listed as missing, 26 have been scrapped, 170 have been traded to the Romulans, and 20 have been sold to ranking families within the empire.
       The D-7C, introduced at the close of the Four Years War, saw no action in that conflict, but it was given its baptism of fire just seven months after entering service. The D-7Cs involved in the incident were so badly outclassed by their RomuIan adversaries that the design was never fully accepted by starship captains, and the model was finally removed from service on Stardate 2/2004.
       The D-7C, named "Bringer Of Destiny" from the Klingon K'tkara, had more efficient warp engines than those mounted on the D-7A, but they were incapable of powering all the weapons even though the ship was more maneuverable. The designers felt that the increased warp speed and maneuvering ratio would make this ship more cost-effective, even though it was a dismal failure because it did not meet its design requirements as a gunship due to its inability to power all its disruptors during combat. Furthermore, though the D-7C had slightly improved shielding, this advantage was lost due to its weaker superstructure. For some unexplained reason, Klingons have never put larger warp engines on this ship, though it seems that, if this had been done early in its career, it certainly would have outclassed anything the Romulans or Star Fleet had at the time.
       Of the 162 D-7Cs built, 52 have been placed in reserve fleets, 66 have been destroyed, 13 captured (9 by Star Fleet, and 4 by the Romulans) 4 listed as missing, 18 sold to the Orions, 6 sold to prominent families within the Empire, and 4 sold to private groups or individuals in the Triangle.
       The D-7G, named "Truthbringer" after the Klingon K’talla, was the direct result of the first Romulan-Klingon technology exchanges, as part of which the Klingons received 24 Romulan plasma weapons of the RPL-1 type. Sixteen of these were immediately installed on D-7s, and the remaining weapons were given to weapons research firms within the Empire. The conversions to D-7Gs were made on D-7As which otherwise remained the same. The plasma weapon design required the ship to be close to the enemy in order to fire, and most Klingon commanders did not like the tactics that the weapon dictated, hence no Klingon commander felt comfortable with the conversions.
       Of the 16 D-7Gs built,10 were converted to D-7Rs, 4 were destroyed, 1 was captured by Star Fleet, and 1 is in the service of a ranking family within the Empire.
       The D-7M, introduced on Stardate 2/1105, was a match for the Federation Constitution and Romulan V-6 (Gallant Wing) cruisers. This gave the Klingon navy a slight advantage along its borders, and the Imperial Command began to press the balance more aggressively. Both the Romulan Star Navy and Starfleet commissioned upgraded versions of their vessels shortly after the appearance of the D-7M, in order to hold the Klingons in check. Within two years after its introduction into service, 75% of all facilities producing the D-7A had been converted to manufacture the D-7M, allowing the Klingons to place more and more of these ships in sensitive areas. As the Klingons grew bolder, these ships began to appear in the Organian Treaty Zone and in the Triangle. Traveling in groups of threes, sorties were made by Klingon commanders into areas that were declared neutral or de-militarized, and several worlds were subjugated by small forces of these ships.
       The D-7M mounts the KWE-3 warp engine, which (in this configuration) gives more efficient power for maneuver and added power for the weapons systems; this warp drive system allowed the D-7 to travel at Warp 8 and, in an emergency, Warp 9. The KD-6 disruptors were replaced with the more powerful KD-8s, extending the offensive range of the ship to 200,000 km. An additional improvement, giving a punch that surprised many Romulan and Star Fleet commanders when first encountered, was the KP-3 photon torpedo mounted both fore and aft. Improved shielding was also added, increasing its capabilities by 50%.
       Several vessels of this type, named "Bringer Of Destruction" from the Klingon K’tinga, have gained a level of fame equal to that of the USS Enterprise, most notably the IKV Bardur. The Bardur is known to have destroyed over 20 Romulan vessels, 10 Federation vessels, and participated in skirmishes that have accounted for the loss of over 40 enemy ships. The captain of this ship has been promoted to Admiral and, much like his Federation counterpart, remains in command of his vessel, now the smallest ship in known space to be a fleet flagship. The current position of this fleet is in the Orion sector, operating from the border starbase located there.
       Of the 1,244 D-7Ms built, 965 remain in active service, 198 have been destroyed, 8 have been captured (5 by Starfleet, and 3 by the Romulans), 11 have been scrapped, 36 are in the service of ranking families of the Empire, and 21 have been reported as missing. Three of those missing were destroyed during the V'ger Incident, and several others are known to be operating in the Triangle under the command of renegade Klingons.
       The D-7R, named "Bringer Of Agony" after the Klingon K'trika, was another attempt by the Klingons to make use of the plasma weapons, this time incorporated into the improved D-7M hull with the photon torpedo bays removed. The RPL-1 was placed in the bow of the ship and an additional KD-8 disruptor was placed in the aft compartment. In addition to these changes, a KCC cloaking device was added. The Klingons had learned by this time that the plasma weapon and cloak were designed to be used together, often by remaining cloaked and stationary in the path of their adversary before decloaking and firing the plasma bolt at minimum range.
       Of the 32 D-7Rs built, 29 remain in active service, 2 have been destroyed, and 1 has been captured by Starfleet.
       The D-7S, the newest of this line of cruisers, is an improved version of the D-7M, appearing to be a D-7M at first glance. Only well-trained personnel will be able to tell the difference on a sensor scan, but these cruisers mount six KD-8 disruptors and fore and aft-firing KP-4 torpedoes. In addition, some models carry the KCC cloaking device.
       The D-7S, named "Bringer Of Justice" from the Klingon K'tmara, is being produced at the same facilities as the D-7M, which intelligence reports show will be phased out for this much-improved version; the facilities at Taamar, Gnuu Re', losia, H'rez, and Z'hai are producing 40 M models and 22 S models per year, Of the 66 D-7Ss built, 65 remain in active service and one has been listed as missing. Although Starfleet has encountered these vessels, none have been destroyed or captured. Orion reports from within the Triangle suggest that the Klingons are operating several small groups there.