Klingon warbird

The Klingon warbird was a class of warship used by the Klingon Empire in the mid-22nd century and in the mid-23rd century of the alternate reality.

In 2151, the Vulcan diplomat Tos claimed that the Klingons would have sent a squadron of warbirds to attack Earth, had he not negotiated for the transport of Klaang's corpse to Qo'noS. 

In 2258, in the alternate reality, Cadet heard a transmission that 47 Klingon warbirds were destroyed by a single Romulan ship, that was later on identified as the Narada, when it attacked the Klingon prison planet.

During the same year, Klingon warbirds were also part of the Kobayashi Maru scenario. These simulated warbirds were capable of cloaking, had shields, and were armed with photon torpedoes. During 's third attempt at the scenario, two of five of these vessels entered the neutral zone before locking weapons on the USS Trainer captained by Kirk. Moments later, the three other warbirds decloaked while targeting the Starfleet craft, and then began firing torpedoes as they simultaneously maintained shields. After the simulation was affected by a subroutine that Kirk had secretly inserted, the shields of the warbirds were suddenly eliminated and the Klingon vessels were all vulnerable to a single photon torpedo strike each. 

Background information
The warbirds in were designed by John Eaves. In a scene deleted from the film, after the Narada is disabled by USS Kelvin's attack, a fleet of ten Klingon warbirds decloak and surround Nero's ship.

The use of the term "warbird" in relation to the Klingons, as used in, was a writer's error. Soon after the episode's production, Brannon Braga stated, "We made one mistake where in the pilot we called the Klingons' ships warbirds, when in fact the Romulans use warbirds and Klingons use the bird-of-prey. There was nothing we could do about it, and I'm sure we're going to get a lot of angry fans. But it was an honest mistake." (Star Trek: The Magazine Volume 2, Issue 9, p. 20)

Klingonischer Warbird Oiseau-de-Guerre Klingon クリンゴン・ウォーバード