This class is one of the earliest class of starships encountered by Earth Starfleet during the early 2150s. The first encounter occurred on the outer perimeter of the Sol system in early 2153. (ENT: "The Expanse") Starfleet, however, had known of the existence of these ships as early as late 2151. (ENT: "Sleeping Dogs")
This Bird-of-Prey design was revamped over the next two centuries, and was used to represent several different variations of this class that were collectively known under the same name. (Star Trek III: The Search for Spock)
Comparable in design to its sister classes, the Raptor-class scout vessel and D5-class battle cruiser, the exterior design of the Bird-of-Prey utilized the same basic avian design, including vaguely feather-like hull plating on its wings.
The bulk of the ship's overall mass was incorporated in the aft section of the ship. The bridge module was located on a bulbous forward section, which was separated from the aft section by a relatively thin 'neck' that attached to and flared into the aft portion which swept down below the main body, forming wings.
Located on the caudal section of the ship were the ship's shuttlebay, impulse engines and two warp nacelles. The port and starboard nacelles were directly connected to the extreme upper aft section of the ship, perpendicular to the impulse engine. (ENT: "The Augments", "Divergence")
The offensive arsenal of the Bird-of-Prey was rather impressive, for the time, as the ship possessed at least eight forward disruptor banks, including a twin pair of neck-mounted disruptor cannons, a pair of wing-tip mounted disruptor cannons, and a 360º rotating turret containing twin belly-mounted disruptor cannons. The class was also equipped with dual photon torpedo launchers, positioned fore and aft, and defensive shields. (ENT: "The Expanse", "Borderland", "Cold Station 12") This class, however, had minimal aft weapons. (ENT: "The Augments")
Prior to the refitting of Enterprise, one Bird-of-Prey was more than a match with the NX-class; however, it was unable to repel three older Earth vessels at one time. After Enterprise was upgraded, it was nearly an even match with the Bird-of-Prey. (ENT: "The Expanse") This class of Bird-of-Prey could outgun an Orion Interceptor, two to one. (ENT: "Borderland")
This class of vessel was equipped with tractor beam technology. It had one emitter located on the underside of each wing that, when used in conjunction, could be used to manipulate a ship to its belly docking port. (ENT: "Borderland")
One major flaw of the Bird-of-Prey's design was found at the nape of the ship's neck and primary hull; a direct hit on the main plasma junction, located above the sensor array, could disable the entire power grid. (ENT: "The Augments")
The shuttlebay was located on the extreme aft of the ship, directly below the impulse engines. It was large enough in capacity to store a Denobulan medical ship. (ENT: "Cold Station 12", "The Augments")
The configuration of the Bird-of-Prey's main bridge shared with many features found in contemporary designs.
In the front of the bridge, against the forward bulkhead, was the ship's viewscreen. Directly behind the viewscreen, near the center of the bridge was the captain's chair. Directly behind the captain's chair, was the entryway to the bridge, with two manned consoles located on either side of the doorway. Along the perimeter of the bridge were several stations, each designated for a specific task. (ENT: "Borderland", "Cold Station 12", "The Augments")
The obvious comfort of these quarters contradicts later Bird-of-Prey designs, as Captain K'Vada had stated to Jean-Luc Picard and Data nearly two centuries later that Klingon warriors did not "soften" their bodies with padding.
The term "Bird-of-Prey" was first referenced on Enterprise in "Sleeping Dogs", and may have been implied to be "two ships approaching at high warp" at the end of that episode. An earlier reference made in "Broken Bow" to "a fleet of warbirds" might have originally been intended to be a reference to the Bird-of-Prey.
The "Bird-of-Prey" designation was initially believed to be a Romulan term adopted by the Klingons in the late 23rd century. With the appearance of ships of this name in use by both Klingons and Romulans during the 2150s, the "in-universe" origin of the term is much more obscure.
The process of designing a 22nd-century style of Klingon Bird-of-Prey began when the producers of Star Trek: Enterprise asked John Eaves to design such a ship. Since Eaves had devised a modified Klingon Bird-of-Prey for Star Trek: Deep Space Nine but it hadn't been used, he thought he had already done half the job of planning a new Klingon Bird-of-Prey. He thus pulled out his earlier concept drawing and submitted the design again. However, the producers notified him it wasn't what they wanted, because it looked too modern. As a result, Eaves had to begin the design process again. (Star Trek: The Official Starships Collection, issue 35, pp. 12 & 13)
Ultimately, the 22nd century variant of Klingon Bird-of-Prey was influenced by the fact John Eaves and his associates had been designing many Klingon crafts beforehand. "So when we got to this Bird-of-Prey," said Eaves, "I did a combination of the Raptor, the old Bird-of-Prey and the Klingon tanker. It's kind of a little bit of everything." External cabling which extends from the bridge module to the top of the ship and which is also at the back of the wings came from an unused D4 class design. (Star Trek: The Official Starships Collection, issue 35, p. 12)
It was clear the 22nd century style of Bird-of-Prey had to look like an ancestor of the original Klingon Bird-of-Prey, which was designed by Nilo Rodis and first appeared in Star Trek III: The Search for Spock. (; Star Trek: The Official Starships Collection, issue 35, p. 13) "What we had to do was pull it back in time," John Eaves explained. "I took the idea that the engine pods were dangerous and made them more elevated so the working area is further away from the reactors." Although Eaves believed there was beauty in the segment of the traditional Klingon Bird-of-Prey where the hinge for the wings was hidden, he slightly adjusted the equivalent area for his redesign. "I made that a little cruder," he recalled, "and the elements were a little more built on." Eaves also decided to depart from the original Bird-of-Prey layout by adding more hull-mounted weapons, such as disruptor cannons on the side of the bridge module and midway along the vessel's underside. (Star Trek: The Official Starships Collection, issue 35, p. 13)
When he added disruptor cannons to the side of the bridge, John Eaves was inspired by a long-held passion for battleships. Similarly, the "big belly cannon" on the craft's underside was influenced by him having had, for a long time, a love of belly cannons seen on many older aircrafts, for example the A-10. "That helped to make it a really aggressive little ship," noted Eaves. (Star Trek: The Official Starships Collection, issue 35, p. 13)
John Eaves did at least two concept sketches of the ship, which he was delighted to design.  He concluded, "The elements are really recognizable [....] It's a very similar design [to the original Klingon Bird-of-Prey] [....] It's pretty badass!" (Star Trek: The Official Starships Collection, issue 35, p. 13) The craft was built as a CGI model by Koji Kuramura at Eden FX. Doug Drexler remarked, "It has a paired down feel to it like a muscular dune buggy [and an] [...] aggressive trademark stance." Rick Sternbach enthused, "I like the big tubes. Looks like a fast way to get to an escape pod (oh, wait…Klingons don't have escape pods), or a fast way to dump a subordinate who wants to take over," Sternbach joked.
Star Trek: The Official Starships Collection (issue 35, p. 3) characterizes the 2150s Klingon Bird-of-Prey as a scout ship with a length of 145.36 meters and a top speed of warp 5.