|KF-X / IF-X|
|KAI KF-X Miniature in Seoul ADEX 2017|
|Manufacturer||Korea Aerospace Industries |
|Designer||Agency for Defense Development |
Korea Aerospace Industries
|Introduction||Plan Timetable - First Prototype Roll Out 2021, First flight 2022, Initial operating capability 2025|
|Status||In development, expected to deploy 120 by 2032.|
< US$70 million
The KAI KF-X, also known as IA IF-X in Indonesia, is a joint South Korean and Indonesian fighter aircraft development program, intending to develop an advanced multirole fighter for the Republic of Korea Air Force and Indonesian Air Force. The program is spearheaded by South Korea, holding 80% of shares, and was joined by Indonesia in 2010 for the remaining 20% of the shares. KAI KF-X is an acronym for Korea Aerospace Industries: Korean Fighter - eXperimental, and IA IF-X stands for Indonesian Aerospace: Indonesian Fighter - eXperimental, describing the main project companies and the experimental nature of the program. The KAI KF-X is South Korea's second domestic fighter jet development program, following the FA-50.
- 1 Design and development
- 2 Issues
- 3 Specifications
- 4 See also
- 5 References
- 6 External links
Design and development
The project was first announced in March 2001 by South Korean President Kim Dae-Jung at a graduation ceremony at the Korea Air Force Academy. South Korea and Indonesia agreed to cooperate in the production of KF-X/IF-X warplanes in Seoul on July 15, 2010, agreeing to produce roughly 150 to 200 aircraft, of which Indonesia would procure 50.
The initial operational requirements for the KF-X/IF-X program as stated by South Korea's Agency for Defence Development were to develop a single-seat, twin-engine jet with stealth capabilities beyond both the Dassault Rafale and Eurofighter Typhoon, but not as stealthy as the Lockheed Martin F-35 Lightning II.
According to the Weapon Systems Concept Development and Application Research Center of Konkuk University, the KF-X is intended to be superior to the F-16 Fighting Falcon, replacing South Korea's aging F-4D/E Phantom II and F-5E/F Tiger II aircraft, with production numbers estimated to be over 250 aircraft. Compared to the F-16, the KF-X will have a 50% greater combat radius, 34% longer airframe lifespan, better avionics including a Hanwha-produced AESA radar, and better electronic warfare, IRST, and datalink capabilities. Operational requirements also specify approximately 50,000 pounds (23,000 kg) of thrust provided by one or preferably two engines, high-speed interception and supercruise capabilities, basic stealth technology, and multirole capabilities.
South Korea will fund 80% of the aircraft's development, and expects foreign partners to provide the remaining 20% of the development funding. South Korea possesses 63% of the necessary technology to produce the KF-X, and is therefore seeking cooperation from Indonesian Aerospace, Turkish Aerospace Industries, Saab, Boeing, and Lockheed Martin to develop the KF-X. About 120 KF-Xs would be built initially and more than 130 aircraft would be produced additionally after the first-phase models reach operational capability. The cost of each KF-X aircraft is estimated to be roughly $50 million +.
Code-named the KF–X and also known as the Boramae program, the project has been under discussion for some 14 years. Indonesia will provide 20% of the development costs, with a Korean domestic company (to be) chosen covering 20%, and the Korean government supporting the rest. South Korea contracted Korea Aerospace Industries (KAI) on 28 December 2015 to develop the KF-X fighter from 2016–26, with deliveries due to begin 2026.
|Expenditures on R&D||Total|
|₩44 bn/ $40.7 mn||₩11 bn/ $10.1 mn||₩55 bn/ $50.9 mn|
- Full Scale Development; 2015~
|Expenditures on R&D||Total|
|2015||₩55.2 bn/ $50.9 mn||?||?|
|2016||₩67 bn/ $61.8 mn||?||?|
|2017||₩303 bn/ $279.6 mn||?||?|
|2018||₩435.3 bn/ $401.7 mn||?||?|
|2019||₩664.1 bn/ $595.1 mn||?||?|
Indonesian investment in the KF-X/IF-X
On 15 July 2010, the Indonesian government agreed to fund 20% of KF-X project cost in return for one prototype, design participation, technical data, and production sharing. In September 2010, Indonesia sent a team of legal and aviation experts to South Korea consisting of around 30 people to participate in first phase (technical phase) of KFX research program and to discuss copyright issues of the aircraft.
A decision on the selection of either design lines was expected to be made in 2013.
However, Indonesian Defense Ministry spokesman Pos Hutabarat announced a 1.5-year suspension of the project in 2013. This delay was said to be caused by uneasiness in the new South Korean government over the expense of the program.
On 20 April 2011, South Korea's Defense Acquisition Programme Administration (DAPA) confirmed the signing of a definitive agreement between South Korea and Indonesia to jointly develop the Korean KF-X next-generation fighter aircraft.
In July 2013, the Indonesian government announced it intends to continue development of the KF-X. Indonesian Aerospace is getting ready to undertake the second stage of the aircraft's development. Indonesia sends around 100 engineers (in other publication the number is 80 engineers)in the second phase of development to help aid the program 
|KAI KFX-E||ADD C103||ADD/ KAI C105||ADD/ KAI C109|
|Empty weight||9.3 metric tons (20,500 lb)||10.9 metric tons (24,000 lb)||11.1 metric tons (24,420 lb)||11.8 metric tons (26,000 lb)|
|Max weight||20.9 metric tons (46,000 lb)||24 metric tons (53,000 lb)||24.5 metric tons (53,900 lb)||25.4 metric tons (56,000 lb)|
|Internal fuel||3.6 metric tons (8,000 lb)||5.4 metric tons (12,000 lb)||5.4 metric tons (12,000 lb)||5.4 metric tons (12,000 lb)|
|Wingspan||9.8 meters (32 ft)||10.7 meters (35.2 ft)||11.0 meters (36.08 ft)||11.2 meters (36.75 ft)|
|Length||15.2 meters (50 ft)||15.7 meters (51.3 ft)||16.0 meters (52.49 ft)||16.9 meters (55.4 ft)|
|Wing area||37.1 square meters (400 square ft)||42.7 square meters (460 square ft)||42.7 square meters (460 square ft)||46.5 square meters (500 square ft)|
|Engine||1 X P&W F100 or GE F110||2 X EJ200 or GE F414||2 X GE F414||2 X GE F414|
|Weapons bay||None||Space provided||Space provision||Space provision|
On 5 January 2014, DAPA announced the approval of development of the KF-X after nearly a decade of attempts with the allocation of 20 billion won (US$19 million). With the start of development, the feasibility of designs and specifications began to be reviewed. The ADD concepts include the F-35-style C103 and the European-style C203 with canards in a stealth frame; both would be powered by minimum of two 20,000 lb (9,100 kg) engines. ADD claims an aircraft larger than the KF-16 has more room for upgrades; a KF-X Block 2 would have internal weapons bays, and a Block 3 would have true stealth comparable to the F-35 or B-2. The Air Force prefers a twin-engine fighter for safety and range. KAI's offering has been dubbed the C501, a concept with a single 29,000 lb (13,000 kg) engine based on the FA-50 with low-observable features and advanced avionics. The C501 is modeled for affordability and performance based on available technologies. Lockheed, who co-designed the T-50 jet trainer, supports the single-engine concept for being cheaper and quicker to develop than a clean-sheet aircraft, but says it will support whichever decision is made. The Korea Institute for Defense Analyses (KIDA) also supports KAI, believing South Korea is not yet ready or able to compete with fighters made by U.S. or European companies; they expect the development cost of the program will be at least 10 trillion won ($9.27 billion).
Bidding by manufacturers for the KF-X was to begin in April 2014. The desire to domestically develop a fighter is driven in part by the intention to export it to foreign buyers, something the country could not do with American-built aircraft. The design of the fighter was still not decided upon, with the ADD proposing the twin-engine clean-sheet C103, and DAPA favoring the single-engine C501 largely derived from technology from the FA-50. The ROK Air Force is interested in a twin-engine aircraft that, although more expensive, has a larger payload capacity, longer range, greater safety if an engine is lost, and better ability to incorporate future upgrades; the initial 4.5-generation C103 can be later upgraded to fifth-generation standard. Developing the C501 would result in a fourth-generation fighter that cannot replace the country's F-15 and F-16 fighter fleets in the future, and would be obsolete by the time it is planned to enter service around 2023 by advanced stealth jets fielded by South Korea's neighbors. Upsizing the FA-50 airframe into the C501 would be more expensive to redesign its aerodynamics and would lengthen development time. In November 2013, the Korea Institute of Science and Technology Evaluation and Planning (KISTEP) calculated the single-engine C501 to be cheaper and faster to develop than the C103, 6.4 trillion won over 8.5 years compared to 8.6 trillion won over 10.5 years, and cost 1 trillion won less to operate and maintain. KAI believes the smaller C501 has better export potential as a medium affordable jet aircraft, possibly to take the place of the closing American F-16 production line; using two large engines may make the KF-X too big and expensive for most of the export fighter market. The Defense Ministry would decide which type of aircraft to proceed with, and the program will be mostly government-funded with limited company financial support.
Along with the final decision on 24 March 2014 to buy the Lockheed F-35 for F-X Phase 3, Seoul plans to ask Lockheed to assist in the development of the KF-X and shoulder 20 percent of the cost. The government is funding 60 percent of development, and Indonesia is taking up another 20 percent. As part of the F-35 deal, Lockheed has offered to provide "300 man-years’ worth of engineering expertise" to assist in designing the KF-X, along with more than 500,000 pages of technical documentation derived from the F-16, F-35, and F-22. Lockheed has had successful joint aircraft development with South Korea in the past; during T-50 jet trainer development, Lockheed covered 13 percent of costs, with KAI covering 17 percent, and the government taking the remaining 70 percent. However, the company is apprehensive about supporting the KF-X program as it may create a medium fighter that can be a competitor in the export market against their own fighters.
The KF-X program is being accelerated, with required operational capabilities to be confirmed by mid-July 2014, and bidding to start as early as one month later. The ADD and ROKAF appeared to have chosen a double-engine airframe for greater payload, mobility, thrust, and safety; proponents for a single-engine design maintain that it would be cheaper, more appealing for export, and that modern engine technologies make engine failure incidents rare. Efforts to accelerate the program may be to address the "air security vacuum" that would occur by 2019, when all F-4s and F-5s would be retired and leave the Air Force 100 planes short. The Joint Chiefs of Staff (JCS) met that month and officially set specifications and a schedule for the KF-X. The KF-X will be equipped with two engines to address future operational needs and keep up with neighboring countries’ aircraft development trends. Heated debates from KIDA, KAI, and the Korea Defense and Security Forum over the higher costs of developing a twin-engine fighter, the potential difficulty in selling it abroad, and that higher costs would block creation of indigenous avionics and force the adoption of foreign systems were countered by Air Force and ADD arguments that Indonesian support will lower costs during mass production, most technologies were already created independently, and that a larger aircraft has more room for upgrades. The initial design is to be a 4.5 generation fighter with a 20,000 lb (9,100 kg)+ payload, with the KF-X Block 2 having an internal weapons bay, and the Block 3 having stealth features comparable to the F-35 Lightning II or B-2 Spirit. Initial operating capability (IOC) is scheduled for 2025, two years later than previously expected.
DAPA issued a request for proposals on 23 December 2014. The finance ministry approved an 8.6991 trillion won ($7.9171 billion) budget for development of the ADD KF-X design, but parliament will not authorize that spending or launch full-scale development until it votes on the government's 2016 budget in December 2015. During that time, Airbus, Boeing, and Korean Airlines are attempting to propose a cheaper alternative to the ADD fighter design and deprive Lockheed Martin of an opportunity to provide technical assistance. The team is likely to offer a version of the F/A-18E/F Super Hornet as a base design. Because the U.S. limits certain technologies that can be transferred abroad, Boeing can provide stealth and radar knowledge through the European Airbus company.
On the 9 February 2015 deadline for submissions, the KAI/Lockheed Martin team submitted their bid but Korean Air and Airbus Defense failed to, the reason likely being more time needed for preparation. Since Korean law mandates at least two bidders for the auction to be valid, the deadline for a second auction was pushed to 24 February. Failure to get another bid in when required will likely delay the program's schedule. If another bid is not received by the third auction, the arms procurement agency is allowed to push forward with only one participant.
On 30 March 2015 KAI/Lockheed Martin was chosen for the KF-X contract over Korean Air and Airbus Defense.
In February 2018, United Technologies announced it had entered the KF-X program to provide the environmental control system, including air-conditioning, the bleed-air, cabin pressurization and liquid cooling systems, as well as the air turbine starter and flow control valve.
In April 2018, it was reported that British companies Cobham plc and Meggitt PLC were selected for aircraft's oxygen system and brake systems respectively. Cobham was also selected in an earlier stages to supply missile ejection launchers, a range of communication, navigation and identification systems, conformal antennas and external fuel tanks and pylons for the aircraft. Meggitt's brake systems are to include carbon brakes on both the nose and main wheels, and a digital brake control system.
In September 2018, Meggitt signed an additional contract with KAI to develop the engine vibration monitoring unit.
Secret design leak
In October 2009 a retired ROKAF general was arrested for leaking classified documents to Saab. The general was to have been given a bribe of several hundred thousand dollars for copies of a number of secret documents that he had photographed in the South Korean Defence University. Saab officials denied any involvement.
Oppositions to the project
The Korea Institute for Defense Analysis, a defense ministry think tank, told a public meeting that South Korea is not technologically equipped to develop the KF-X aircraft, that the project is economically unviable and that the KF-X would not be a successful export product. It questioned the cost estimates by the Agency for Defense Development, which is the lead developer of the aircraft.
A defence researcher, Lee Juhyeong, has told a seminar on the program that the KF-X development would cost more than 10 trillion won ($9.2 billion) and that over the life of the program, the KF-X would cost the country more than twice as much as an imported aircraft.
Another report by the Korea Development Institute in 2007 stated that the KF-X was not viable and that the KF-X export customers can be blocked by Washington because the KF-X used many US-components and electronics.
Critics pointed out that the KFX would cost up to twice (US$100mn a piece) as much as a top-end F-16 model (US$55mn) and pointed out that Japan made the same mistake in the 1990s when they decided to develop and build the Japanese F-2, which cost twice as much as an imported or even locally-built advanced version of the F-16.
EADS pulled out after F-35 purchase
On 23 May 2013, EADS stated that if South Korea selected its Eurofighter Typhoon as the winner of the F-X Phase 3 fighter program, they would invest $2 billion into the KF-X program. The F-35A was selected in November 2013 with 40 planned and the possibility of a split buy for 20 other fighters. EADS has offered a split buy option for 40 Eurofighters and 20 Lightning IIs, and will keep the offer to provide funding to the KF-X program if the Eurofighter is bought. But in September 2017, South Korea confirmed purchased of 40 F-35 fighter jets for about 7.34 trillion won ($7.06 billion) for delivery in 2018-2021, causing EADS to pull out of the KF-X program.
Promotion video controversy
On December 27, 2016, The Korea Times exposed a fake sales promotion video of the KF-X/IFX that was produced with video game footage containing simulation scenes of air combat and the bombing of an aircraft carrier. The two video games, Ace Combat: Assault Horizon by Bandai Namco and Battlefield 3 by Electronic Arts, are shown for about 10 seconds in the video clip, which runs for 10 minutes and 16 seconds and, without their game owners' authorization, constituted copyright violations.
Postponements and Delays
The KAI-KF-X project had a long history of delays and postponements since it was first announced in March 2001 by South Korean President Kim Dae-Jung After several failed attempts to get Sweden, Turkey, and the United States to join the project, it was only in June 2010 that South Korea succeeded in getting Indonesia to join the project, the only country to be a JV partner. However three years later, on March 1, 2013, South Korea put the project on hold for 18 months, due to financial issues and the election of the new South Korean President Park Geun-hye. Indonesia had so far paid $165 million of the then DAPA's estimated 6 billion won (US5.5 billion). Reuters however reported that some analysts said the project could cost up to $8 billion, which meant Indonesia may eventually have to pay $$1.6bn to South Korea.
US refused advanced radar export to South Korea
On February 8, 2017, the Indonesian Vice Minister of Foreign Affairs Abdurrahman Mohammad Fachir said the project was further delayed because the U.S. refused to allow the South Koreans permission to grant export license for four key technologies -active electronically scanned array (AESA) radar, infrared search and track (IRST) system, electronic optics targeting pod (EOTGP), and advanced radio frequency (RF) jamming system. Therefore, South Korea will install advanced locally-made replacements (AESA,IRST,EOTGP etc. by Hanwha System)  on the KF-X instead of off-the-shelf US components.
Financial disputes arose when on November 1, 2017, a member of the South Korean National Assembly Defense Committee, Kim Jong-Dae, stated that non-payment of an overdue contractual payment by Indonesia would further delay the development and production schedules.
Based on documents from the Defense Acquisition Program Administration (DAPA) of the Ministry of National Defense (South Korea), Kim Jong-Dae stated that Indonesia's government-owned defence firm known officially as: PT Dirgantara Indonesia (Persero) (PTDI), but more commonly called: Indonesian Aerospace, a project partner, had failed to pay the remaining allotted 138.9 billion won (US$124.5 million) to Seoul as of the end of October 2017. Under the joint agreement signed in January 2016, Indonesia, through PTDI, would pay 20 percent (US$1.33bn) of the cost of the development of the KF-X program, Korea Aerospace Industries (KAI) also pays 20 percent and the South Korean government pays the remaining 60 percent (US$4.8bn).
Kim Jong-Dae added that the, "Indonesian government had officially disclosed its difficulty in paying 138.9 billion won in late September after it failed to include the money in its budget finalized in August.", of 2017.
DAPA denied knowledge of the details of any Indonesian payment problem but went on to state that South Korean president Moon Jae-in would discuss the payment issue with the Indonesian president Joko Widodo during their summit in Jakarta on November 8, 2017.
According to the Indonesian Finance Minister, the Indonesian Minister of Defense didn't allocate the funding in the 2017 state budget due to a prior false understanding that it should be paid out of what is called the: side defense budget, since it is a: G to G agreement. Thus Indonesia claimed that the problem was more an administrative failure than anything more serious. After learning about the issue the government wanted to pay the required KF-X funding but they needed to go through parliament first to get the green light.
The Indonesian Parliament agreed to allocate Rp1,85T (US$145 Million) to the budget for the KF-X development fund in 2018, and expressed the hope that this program continues without experiencing any more delinquencies like the previous year. 
On 1 May 2018 it was reported that Indonesia had complaints concerning the contracts regarding technical benefits and export licensing. Indonesian state media announced the defense ministry would renegotiate the joint development program in an attempt to get a larger share of local production, as well as export rights. The defense ministry added that it hoped the program would continue, despite setbacks.
Data from Defense Acquisition Program Administration (DAPA)
- Crew: 1 or 2
- Length: 16.9 m (55.4 ft)
- Wingspan: 11.2 m (36.7 ft)
- Height: 4.7 m (15.3 ft)
- Wing area: 46.5 square meters (500 square feet)
- Empty weight: 11,800 kg (26,000 lb)
- Loaded weight: 17,200 kg (38,000 lb)
- Max. takeoff weight: 25,400 kg (56,000 lb)
- Powerplant: 2 × Hanwha Techwin F414-KI afterburning turbofan
- Dry thrust: 13,000lbf (57.8 kN) each
- Thrust with afterburner: 22,000 lbf (97.9 kN) each
- Hardpoints: 10
- Datalink capabilities
- AESA radar by Hanwha Systems
- E/O Targeting System (EOTS)
- Radio Frequency Jammer
In October 2013 at the Seoul International Aerospace & Defense Exhibition, two concept models for the KF-X fighter were displayed. KAI's model, the KFX-E, was designed by the company as a single-engine aircraft with most systems developed for the T-50 trainer and no internal weapons bays. Experience from the T-50, and support provided by Lockheed for that aircraft, was seen as a cost-effective approach, as KAI officials saw a smaller and cheaper proposal to finally get the program to launch and enter service around the mid-2020s.
There are two versions of the KFX-E available, the standard one with a single fin and an optional one with two that would require more development work but has less radar reflection. Although the KFX-E was smaller than the F-35 Lightning II, it was heavier than both the T-50 and F-16, with a 14 percent higher internal fuel capacity than the F-16C Block 40 at 6.36 tons. Its larger wing compared to the F-16 would produce more drag and make it accelerate slower. The other model was designed by Seoul's Agency for Defense Development, who became a competitor to KAI when they judged the ADD design for a twin-engine plane requiring more domestic systems development as too ambitious.
There are actually two ADD proposals, the C103 and C203, both weighing 11 tons empty. They propose initially fielding a low-observable aircraft, then later versions would have full stealth and internal weapons bays. The ADD designs have the advantage of being worked on with Indonesia, the main foreign partner. The C103 and KFX-E have similar tail-aft sections, while the C203 has forward horizontal stabilizers.
Aircraft of comparable role, configuration and era
- HAL AMCA
- Lockheed Martin F-35 Lightning II
- Mikoyan LMFS
- Mitsubishi X-2 Shinshin
- Saab Flygsystem
- Shenyang J-31
- TAI TFX
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- PICTURES: KAI shows off two designs for KFX fighter - Flightglobal.com, 29 October 2013
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