Jinmu ZF-21 Dragon

The Jinmu ZF-21 Dragon is a Zhenian single or twin-seat,, all-weather   developed for the Republic of Zhenia Air Force and the Republic of Zhenia Navy. Although originally intended as an when development began, it has been developed to carry out missions as a multirole fighter, capable of taking out both air superiority and precision ground strike missions, as well as  and  (ISR). Although primarily built by Jinmu Heavy Industries, other contractors, including Signus Systems, took part in the development process as well.

A result of decades of continuous development that had been mostly in secret, the ZF-21 Dragon was first revealed to the public during its test flight on June 4, 1998 and was introduced to service in 2004. Later developed in tandem with the ZF-32 Black Eagle, later variants and upgrades feature a considerable amount of cross-development with technological input gained from developing the ZF-32. Replacing the ZF-7 Typhoon, the ZF-21 Dragon is planned to form the higher end of the GEUDEF's projected of combat aircraft. The Republic of Zhenia Air Force and Navy combined plans to field up to 720 and 450 ZF-21 units in total by 2026.

Armament


In order to preserve its stealthy shape, the ZF-21 is equipped with a total of three internal weapons bays - a large main bay running through the center of the aircraft and two smaller bays on the side of the fuselage, between the landing gear and the air intakes. Split along the center line of the aircraft, the large main bay is capable of accommodating up to six long-range air-to-air missiles at a time, while the smaller side bays are in theory capable of accommodating up to two air-to-air missiles each, although they normally carry only one in practice. Unlike the side bays, the main bay is also capable of carrying a broad range of air-to-surface weapons, being able to carry up to 1,300 kg of ordnance in each hardpoint. Ordnance in both the main bay and side bays are connected to the weapons bay via robotic arms, which are engaged when the weapon is set to be fired. The usage of internal weapon bays allow for non-stealthy ordnance to be carried within the airframe, minimizing radar signatures.

In addition to the internal weapon bays, the ZF-21 is also equipped with three external hardpoints on each its wings, with a capacity of carrying up to 8,000 kg on each side of the wing. The external hardpoints can be used to carry large munitions that do not fit inside the main weapon bay, carry munitions in missions that do not require a stealthy configuration, or external weapon pods to increase its ordnance capacity while maintaining its stealthy configuration. Although only able to be installed at the internal hardpoints on each wing, the external weapons pod is capable of carrying up to four additional long-range air-to-air missiles. The ZF-21 is armed with a 20 mm Gatling gun mounted in the right-hand spot near the wings with 450 rounds for close-range warfare and strafing. The centerline of the aircraft, just behind the main weapon bay, has an additional hardpoint not for munitions but for multi-mission pods, including jammers and reconnaissance pods.

Avionics, Electronics and Sensors
A major element of the ZF-21's system is the Cheongu Distributed Aperture System, a system consisting of multifunction infrared-range camera sensors installed around the airframe. Intended to provide 360-degree coverage around the aircraft in extended ranges, the Cheongu Distributed Aperture System is expected to allow for reconnaissance, threat detection and target acquisition in both air and the surface.

Cockpit
The ZF-21 uses a to maximize the pilot's situational awareness. Primarily centered around a 20-by 8-inch (50 by 20 cm) panoramic and the  at the top, the cockpit's information display system allows for flexible display of flight instruments, aircraft status, information on the aircraft's surroundings and incoming threats. The cockpit itself has been designed to reduce complexity and increase flexibility of screen usage at the end of the pilot, which has been factored into the lack of screen side buttons. While some have proposed to remove the head-up display altogether and replace its functions with a, it has been decided that all variants were to retain the head-up display to augment the pilot's own situational awareness.

Stealth
Although its exact remains a closely-guarded secret, there are speculations that the estimated radar cross-section of the ZF-21 without any external armaments is most likely smaller than 0.001m2 - roughly comparable to a metal golf ball. The ZF-21 was designed to minimize its radar cross-section and probability of being detected by enemy sensors. Such measures include planform alignment on the edges, curved vanes behind the to cover the engine turbines from external radar waves, extensive use of radar-absorbent material (RAM) and minimization of clear bumps and design irregularities that can possibly give a radar return. Reduction of radio emissions, infrared and acoustic signature has also been taken into account upon the ZF-21's design, with its saw-toothed three-dimensional designs both to scatter radar and heat signatures, active cooling on leading edges and other heat-concentrated areas to reduce heat buildup and the internalization of almost all antenna systems.

Although it takes extensive use of radar-absorbent material (RAM), the ZF-21 primarily uses more durable radar-absorbent fibermat skin modules that allow for less and easier maintenance than its predecessors, increasing its and availability in emergency situations. While its stealth is primarily focused on achieving very low observability (VLO) against threats, it is said to also have achieved at least low observability (LO) against S-band and L-band threats, among other lower-frequency threats. Although its exact remains a closely-guarded secret, there are speculations that the estimated radar cross-section of the ZF-21 without any external armaments is most likely smaller than 0.001m2 - roughly comparable to a metal golf ball. The aircraft can additionally mount a total of six reflectors to disguise its actual radar cross-section.