Perhaps the most successful design of vessel in history, the Bird of Prey has been in service in larger numbers over more subtypes for a longer time than any other class in known space. First fielded as the D11 class in the late 2270s, the ship was built from the start to fill a variety of roles. As a special operations ship she could use her cloak to penetrate Federation border defences and attack lightly defended targets such as sensor outposts, communications relays and cargo craft, creating confusion in advance of a Klingon fleet attack. She was also a natural scout ship, ideal for locating and tracking Federation fleets from under cloak. During the long period of tensions between the Federation and Klingon Empire, many D11s operated as raiders, cruising deep inside Federation space to pick off occasional lone vessels or outposts.

The Bird of Prey was a potent threat to the Federation in this role, but many of its secrets were revealed when one was captured by Admiral Kirk in 2285. The Admiral was at this time operating outside of Starfleet authority, and the vessel concerned later sank in San Francisco Bay during an attempted landing; nevertheless, on his return to Starfleet Admiral Kirk and his crew provided full details of the vessel's operation. The ship itself was raised from the water and subjected to detailed analysis. This provided crucial help in devising countermeasures for use against the Bird of Prey, allowing Starfleet to modify the sensor networks already in operation on its ships and installations in order to significantly increase their effectiveness.

The next major variant seen by the Federation was the D11A, a prototype developed by a team working under General Chang in the early 2290s. The vessel was capable of firing torpedoes whilst still under cloak, making it a potent threat on the battlefield. Unfortunately for the Klingons, this development was rendered almost useless by the use of plasma homing torpedoes which homed on the ship's wake. A variant which appeared in the 2350s was the D12, which featured a cloaking device equipped with plasma coils. Unfortunately these proved to be defective, rendering the ships cloak highly vulnerable to ionic pulses. This problem was considered so serious that the Klingons retired the entire class from service. The D12s were replaced with the D13, a class which continues in service to this day, naturally having been vastly upgraded and refitted over the years. In design the Bird of Prey conforms to Klingon norms, with a single torpedo tube at the extreme forward point of the hull. The command centre is above this, with crew quarters - such as they are - located in the 'neck' section directly aft. The rear of the ship comprises the engineering compartments and a small cargo bay. A pair of wings carry small disrupter cannon at their tips, while an emergency torpedo tube provides a backup to the main armament. The wings allow the B'Rel to operate in an atmosphere and landing gear is fitted, the first Warp capable craft known to have this ability.

Type-Light combat/Scout ship

Units-4,191 built in various subtypes since 2277. 2,100 were in service at the onset of the Dominion war or have been built since; 1,452 have been lost during the war, 648 remain in service.

Date of Commission-2277

Dimensions-109meters X 92meters Decks- 4

Mass-30,000 metric tons

Crew Compliment-12-36

Armaments-2 Mark 6 pulse disruptor cannons- total output of 10,000 terawatts.2 Basic photon torpedo tubes + 35 torpedoes, 1 single shot emergency photon torpedo tube.

Defence Systems-Shield system- total capacity of 324,000 terajoules, standard duranium/tritanium single hull, 5.0cm high density armor, standard level structual integrity field..

Warp Speed Capability-Normal Cruise: Warp 5.0 Maximum Cruise: Warp 7.0

Strength Indices(1000 is equal to a Galaxy class ship)-Beam Firepower- 200 , Torpedo Firepower- 100 Weapon accuracy and range- 220 , Shield strengh- 120 , Hull armor- 550 , Speed- 581 , Combat manoeuvrability- 15,000

Overall Strengh Index(out of 1000)- 230

Expected Hull Life-40 years

Refit cycles-Minor: 5 years Standard: 10 years Major: 30 years