KF-20 Chamsuri

KF-20 Chamsuri
RJAF KF-20, 1st Fighter Wing, 2020
General information
Type	Air superiority fighter
National origin	Joseon
Manufacturer	Daesung Aerospace,. Inc.
Designer	Daesung Aerospace,. Inc.
Status	In service
Primary user	Royal Joseon Air Force
History
Manufactured	1995–2007
Introduction date	4 February 1998 (1998-02-04)
First flight	25 June 1995 (1995-06-25)

The Daesung Aerospace KF-20 Chamsuri is a Joseon's twin-engine, all-weather fighter aircraft designed by Daesung Aerospace. The KF-20 is designed as an air superiority fighter but can also perform tasks like ground attacks as a multirole fighter.

Since its successful first test flight in 1995, the KF-20 was introduced in 1998, and 1160 aircraft were manufactured. The Royal Joseon Air Force(RJAF) had planned to replace all KF-20s with KF-24 Huinmae and KF-23 Chammae by the late 2020s, but at least 200 are expected to be active by the 2030s, in line with the Defense Committee of the National Assembly's recommendation to maintain a certain number of non-stealth multirole fighter jets.

Like all other combat equipment and vehicles in the Royal Joseon Armed Forces, the KF-20 is also integrated into the Joseon's Battle Management System(BMS), 'Gongmyeong-2E,' sharing real-time information about battlefields and changes in conditions with other units and aircraft, vehicles, and ships.

Development

In 1989, the RJAF submitted a requirement institution to the Ministry of Defence for new fighter jets to secure the ability to respond to the Su-27 and its variant fighters, and to serve as a platform for various stand-off and ground-attack weapons.

Two companies participated in the open bidding, with Daesung Aerospace proposing the XA-20 model and Korea Aerospace Industries(KAI) proposing the FX-21 model. The XA-20 had the advantage of being more high-performance, while the FX-21 was cheaper, and more scalable in system platforms. The bidding competition between the two companies changed in 1990 when Royal Joseon Navy(RJN) submitted a requirement institution for a new aircraft carrier-based fighter jet. KAI ceded the Air Force's business to Daesung Aerospace, who ceded the Navy's business to KAI. This was because the requirements of the Air Force and Navy met KAI's proposal model, respectively, or Daesung Aerospace's proposal model.

Daesung Aerospace designed the KF-20 based on the XA-20 model, and KAI designed the KF-21 based on the FX-21 model. Both aircraft models were named the next generation of fighter jets for the Air Force and the Navy.

The KF-20 succeeded in its first flight on June 25, 1995. A total of 10 prototype aircraft conducted flight tests and armed tests until 1998, and since the first aircraft was delivered to the Air Force in 1997, the KF-20 has been active since 1998.

Design

Radar signature reduction measures

The KF-20 has applied several stealth designs to reduce the RCS(Radar cross-section), even though it is classified as a non-stealth aircraft, a 4.5th generation fighter. The KF-20 is designed to allow the vertical stabilizers to have a certain level of inclination, ensuring stealth capabilities on some aspects of the aircraft. The design of the engine inlets reduces the KF-20's frontal RCS. The alignment of the leading edges of the engine inlets is designed to scatter radiation to the sides. Fixed fanlike reflecting structures in the inlet tunnel divert radar energy away from the rotating fan blades. The KF-20 also makes considerable use of panel joint serration and edge alignment to direct reflected waves away from the aircraft in uniformly narrow angles. Considerable attention is paid to the removal or filling of unnecessary surface join gaps and resonant cavities. The KF-20 has a frontal RCS an order of magnitude smaller than prior generation fighters.

Avionics

The KF-20's AN/APG-01 AESA radar can detect aircraft with an RCS 1m^2 size at 190km. Also, the AN/APG-02 radar also has high-resolution mapping, and moving target tracking capability (GMTI) capabilities. AN/APG-01 is highly resistant to DRFM jammer attacks due to enhanced electronic protection capabilities, can organically change frequencies or patterns of radio waves, and radio algorithms are also very complex, reducing the risk of exposure to locations through radio backtracking by enemy ESM equipment or Passive radar. The AN/APG-01 radar can also detect smaller targets, such as inbound missiles and can track air targets beyond the range of the aircraft's air-to-air missiles.

The first KF-20 upgraded with the Joint Helmet Mounted Cueing System (JHMCS) was delivered to the RJAF on 18 May 2013. The JHMCS provides multi-purpose situational awareness, which includes high-off-boresight missile cuing. The Shared Reconnaissance Pod (SHARP) is a high-resolution, digital tactical aerial reconnaissance system that features advanced day/night and all-weather capability.

Since 2019, the KF-20 has been equipped with KAN/AAQ-04-S EOTS, a miniaturized version of the KAN/AAQ-04 EOTS mounted on the KF-23 and KF-24. KAN/AAQ-04-S EOTS is responsible for exploring the approximate location of enemy stealth targets detected by KF-24 using a X-Band radar in more detail, identifying detailed location information of enemy stealth targets, and guiding radar-guided missiles, including AIM-120D, to enemy stealth targets. The EOTS equipped on the KF-20 has a detection range of 150 kilometers, and if necessary, the KF-20 can perform BVR(Beyond-visual-range) air combat using only EOTS without radar operation.

The KF-20 uses a fly-by-wire control system to improve the flight stability of the aircraft.

Engines

The Hanwha Aerospace JT-144 is a low-bypass axial-flow afterburning turbofan. It has a 3-stage fan driven by a two-stage low-pressure turbine and a 9-stage compressor driven by a one-stage high-pressure turbine; overall pressure ratio is 30.4 and bypass ratio is 0.87. In contrast to the ambitious raw performance goals for the JT-144 of high thrust and low weight, the F110 placed a greater emphasis on balancing between reliability, operability, and performance. The fan and inlet guide vanes were designed to smooth airflow to increase resistance to compressor stalls. The engine has an electronic and hydromechanical control system that make it more forgiving of rapid throttle inputs.

The KF-20 is capable of supersonic cruise (supercruise) without using afterburners. RJAF evaluation a maximum supercruise speed of Mach 1.5 for the KF-20.

Helmet

The Vision Systems International helmet display has been integrated into KF-20 since 2015. The Vision Systems International helmet display is a key piece of the KF-20's human-machine interface. Instead of the head-up display mounted atop the dashboard of earlier fighters, the HMDS puts flight and combat information on the helmet visor, allowing the pilot to see it no matter which way they are facing. Infrared and night vision imagery from the Distributed Aperture System can be displayed directly on the HMDS and enables the pilot to "see through" the aircraft. The HMDS allows a KF-20 pilot to fire missiles at targets even when the nose of the aircraft is pointing elsewhere by cuing missile seekers at high angles off-boresight.

Armaments

There are a total of 11 hard points in the KF-20, each of which can be equipped with short/medium/long range air-to-air missiles, stand-off weapons, ground attack weapons, and external fuel tanks.

Protection

The defensive countermeasures of the KF-20 includes the AN/ALR-67(V)3 radar warning receiver, the AN/ALE-47 countermeasures dispenser, the ALE-55 towed decoys and the AN/ALQ-214 Integrated Defensive Countermeasures (IDECM) system.

The KF-20 has military-grade protection against non-nuclear and nuclear shock wave EMPs.

Operators

• Joseon
  • Royal Joseon Armed Forces
    • Royal Joseon Air Force
    • Royal Joseon Navy

Specifications

General characteristics

• Crew: 2
• Length: 19.44 m
• Wingspan: 13.05 m
• Height: 5.63 m
• Empty weight: 34,600 lb (15,694 kg)
• Max takeoff weight: 81,000 lb (36,741 kg)
• Fuel capacity: 12,915 lb (5,858 kg) internal
• Powerplant: 2 x Hanwha Aerospace JT-144 turbofans, 17,800 lb dry (79 kN); 29,160 lb (129.7 kN) with afterburner each

Performance

• Maximum speed:
  • Mach 2.5, 1,650 mph (2,655 km/h) at high altitude
  • Mach 1.2 / 800 kn (921 mph; 1,482 km/h) at low altitude
  • Supercruise: Mach 1.5
• Range:
  • Combat range: 687 nmi (791 mi, 1,272 km)
  • 2,100 nmi (2,400 mi, 3,900 km) with conformal fuel tanks and three external fuel tanks
• Service ceiling: 60,000 ft (18,000 m)
• g limits: +9.5

Armament

• Gun: 1× 20 mm M61A2 Vulcan rotary cannon, 540 rounds
• Air-to-air mission loadout(Internal weapons bays)
  • 8 x AIM-120C/D AMRAAM or KAIM-3 + 2 x AIM-9M/X Sidewinder
  • 12 x AIM-120C/D AMRAAM or KAIM-3 + 2 x AIM-9M/X Sidewinder
• Air-to-ground mission loadout(Internal weapons bays)
  • 4 x 2,000 lb JDAM + 2 x AIM-120C/D AMRAAM or KAIM-3 + 2 x AIM-9M/X Sidewinder
  • 10 x 1,000 lb JDAM + 2 x AIM-120C/D AMRAAM or KAIM-3 + 2 x AIM-9M/X Sidewinder
  • 4 x 2,000 lb GBU-24 Paveway III + 2 x AIM-120C/D AMRAAM or KAIM-3 + 2 x AIM-9M/X Sidewinder
  • 10 x 500 lb Paveway IV + 2 x AIM-120C/D AMRAAM or KAIM-3 + 2 x AIM-9M/X Sidewinder
  • 10 x 1,000 lb GBU-16 Paveway II + 2 x AIM-120C/D AMRAAM or KAIM-3 + 2 x AIM-9M/X Sidewinder
  • 18 x 250 lb GBU-39 SDB + 2 x AIM-120C/D AMRAAM or KAIM-3 + 2 x AIM-9M/X Sidewinder
  • 4 x AGM-158 JASSM + 4 x AIM-120C/D AMRAAM or KAIM-3 + 2 x AIM-9M/X Sidewinder
  • 6 x AGM-65E/F Maverick + 2 x AIM-120C/D AMRAAM or KAIM-3 + 2 x AIM-9M/X Sidewinder
• Air-to-ship mission loadout(Internal weapons bays)
  • 4 x NGAM + 2 x AIM-120C/D AMRAAM or KAIM-3 + 2 x AIM-9M/X Sidewinder
  • 4 x ASM-1100K + 2 x AIM-120C/D AMRAAM or KAIM-3 + 2 x AIM-9M/X Sidewinder
  • 4 x AGM-158C LRASM + 2 x AIM-120C/D AMRAAM or KAIM-3 + 2 x AIM-9M/X Sidewinder
  • 4 x Joint Strike Missile (JSM) + 2 x AIM-120C/D AMRAAM or KAIM-3 + 2 x AIM-9M/X Sidewinder

Avionics

• AN/APG-01 X-Band AESA Radar
• AN/ALR-94 RWR
• KAN/AAQ-04-S EOTS
• KAN/ASQ-23 "Witch" Electronic Warfare System