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IFX Indonesian Fighter Experiment (KF21/IFX program)

[Graphic] Status of Indonesian contribution for joint development of KF-21


(Seoul = Yonhap News) Reporter Ban Jong-bin = Defense Acquisition Program Administration Director Eom Dong-hwan visited Indonesia on the 5th to resolve the issue of contributions for the domestically produced supersonic fighter KF-21.

The two countries are currently carrying out the KF-21 (Indonesian name IF-X) project to jointly develop a fighter jet by jointly covering a project cost of 8.1 trillion won from 2015 to 2026.bjbin@yna.co.kr


Korean DAPA Director will meet Moeldoko, Presidency Chief of Staff, in Jakarta starting Today. Talks is expected to last until end of Weekend.

This shows that KF21 program is now lead by Jokowi himself, not Prabowo any more as Defense Minister. Previously it is always Defense Ministry team (whether Defense Minister or his deputy) who carried talk with South Korea, but now it is different.

On last Monday, Moeldoko had meeting with Defense Ministry, Finance Ministry, and Planning Minister (Bappenas) to discuss KF21/IFX program.
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Jokowi criticizing Prabowo in the Armed Force Day Celebration Today, on 5 October about his defense acquisition spending. His critics is more on the imported equipment. I think with this speech, Rafale acquisition will likely just reach 24 planes and no F15 EX contract is likely to ever sign, even for just 8 planes.

His full speech :

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Need to note that Indonesia is part of developer since the start, it is not license manufacturing. My connection in KFX/IFX team also said that the cooperation in KFX/IFX program is similar like Indonesia cooperation in CN235 as joint developer.

I get called as Idiot by Ananda from DT by saying that KF21/IFX program cooperation is similar like CN 235 LOL.

We all know that Indonesia is junior partner with 20 % stake, I just want to debunk his rumble saying Indonesia cooperation is similar like license production so better license assembling FA50 than cooperating in KF21 program.

That guy is part of the group in Indonesia who dont want to see Indonesian advancement and Alhamdulillah Indonesia is still joining and participating on the program. Contrary to their wish......

Seeing Indonesian Aerospace can be part of KF21 program is already getting many people feel irritated, outside and inside (for some group in Indonesia). They dont want to see Indonesia become part of the program.....

Now I need to explain again about what is the cooperation is all about....

When you develop a plane, you do the engineering development that usually last about 10 years before mass production. That is different with license production. How many times I need to explain to him duh....

Here I will show the engineering process conducted by Indonesian engineers.

What was the design process for the KF-X/IF-X?

Engineers who designed the KF-X/IF-X were divided into several sections, namely configuration, structure, propulsion, systems and aerodynamics.

The engineer working on the configuration section will work first, determining the general dimensions of the aircraft (length, wingspan, etc.), general wing planform, type of empennage, calculations about stealth, armament placement, etc.

When complete, the data will be given to each section for follow-up. For example, in the structural section, engineers must create a wing design based on the limitations created by the configuration engineer (wing length, type of wing planform, wing angle, armament pylon position, etc.) as well as the limitation conditions provided by the aerodynamics engineer.

Apart from that, the structural engineer must determine two different types of materials with different calculations to meet the limits set by the Design Requirements and Objective (DRO), such as the maximum G-load of the aircraft, the maximum weight of weapons that can be carried by each pylon, etc. .

The two types of calculations using different materials will then be given to the DPR (both South Korea and Indonesia) to determine which material will be selected. The selection of materials by the DPR takes many factors into account, starting from the availability of raw resources, the ability to process these raw resources, employment, economic turnover, to cost effectiveness.

What are Indonesia's contributions to the design process?

Indonesia has engineers who work on each part together with South Korean engineers. For example, there are 10 engineers working on structural parts, of which five come from Indonesia. This is done so that Indonesia can gain knowledge from every part that is carried out.

Designing a product must go through the stages of Conceptual Study, Conceptual Design, Preliminary Design, Detailed Design, Prototyping, and finally Mass Production. The Preliminary Design part of the KF-X/IF-X was carried out by engineers who are experienced (40 years and over) and have participated in several previous national strategic projects.

The Preliminary Design stage was successfully completed within 1.5 years.This time is considered very short if you design an aircraft from 0 (starting from scratch) with limited funding. The next stage (detailed design and others) was then continued by engineers from PTDI.

What are Indonesia's advantages compared to South Korea and Indonesia's reciprocity towards the KF-X/IF-X project?

Indonesia has advantages in terms of structure and systems compared to South Korea. Meanwhile, Indonesian experts are in an equal condition in terms of knowledge in the field of composite materials, but Indonesia is behind in terms of manufacturing.

Then, why can South Korea make the T-50 Golden Eagle light trainer jet, but can't make a cargo plane so it has to overhaul the CN-235?

In short, like this, it's like South Korea, through KAI, is an expert in making sports cars (T-50) and Indonesia, through PTDI, is skilled at making transport trucks (CN-235). A company that is skilled at making sports cars may not necessarily be able to make transport trucks because they have different goals and needs even though they are both wheeled land vehicles (in this case planes).KAI itself was able to make the T-50 after receiving assistance from Lockheed-Martin.

Does Indonesia get access to sensitive technology from KF-X/IF-X such as radar, etc.?

No, Indonesia does not get access to sensitive technology from KF-X/IF-X because the sensitive technology comes from third party countries (US, Israel, etc.). While in South Korea, all engineers from Indonesia, including the test pilots who were sent, were under strict supervision by the South Korean NIS (National Intelligence Service).

What contribution does Indonesia have in the production line of the KF-X/IF-X?

Currently, Indonesia has a role in producing components from KF-X/IF-X made from carbon composition, such as components for flight control surfaces.In order to have the ability to produce components from carbon composites, PTDI has purchased two Autoclave machines with diameters of 3-meter and 1.5-meter and equipped with CCA (controlled clean room). This is done so that production from KF-X/IF-X also depends on Indonesia.

Average salary received by Indonesian Engineers who participated in the development of KF-X/IF-X

Because nominal mentions are considered sensitive, what is presented here is a comparison percentage. During the KF-X/IF-X development phase, participating Indonesian Engineers were paid 25% less than South Korean Engineers working on the same part of the program.

Meanwhile, South Korean Engineers are paid 20% less than United States Engineers, which means Indonesian Engineers are paid 40% less than United States Engineers.Even though the salary of Indonesian Engineers involved in the KF-X/IF-X Program looks lower than others, the salary is still 50% higher (1.5x) the salary of Indonesian Aerospace Engineers working on domestic programs.

I want to disclose some of my conversation with my connection on KFX/IFX program.

1. Indonesian KF21 version will be different with Korean version, the development with Indonesian version will be started as soon as KF21 prototype 5 is sent to Indonesian Aerospace. One of the differences for example Indonesian version should be able to land in shorter runway as requirement from our Air Force.

2. Indonesian Aerospace is given task to keep ugrading the KF21 overtime, so the ability to do upgrade is important and this relates to system integration capability that should be enhanced as system integration at this level needs software capability and will be much more independent than Indonesian F16 Falcon Star upgrade. From my connection on Indonesian KFX/IFX team, he said that Falcon Star program conducted in Indonesia is more about plug and instal work while sofware system will be done by Lockheed Martin people.

3. Institute Technology Bandung (ITB) is important in doing fighter jet research in the country. ITB is also involved from day one of KF21 development like shown in my first page with credible Indonesian media (ANGKASA) where ITB lecture is the Indonesian team leader in configuration work package during preliminary design phase (2011-2012). Need to note here that both Indonesian and South Korean will have team leader in each technology packages ( configuration, structure, propulsion, systems and aerodynamics, etc)

4. Indonesian engineers are dominated by senior engineers in the beginning of development that started in 2011 and then slowly replaced by junior engineers. Current phase for example in the time to prepare mass manufacturing, Indonesian engineers are dominated by junior engineers

5. The transition from KF21 block 1 into KF21 block 2 is not a major thing and he said as something natural for any fighter development. KF 21 block 1 can later be upgraded into block 2. (F15 for example starts from superiority fighter and F15 EX become multi role version)

6. What is important to improve Indonesian Aerospace capability in jet fighter technology is through real fighter development and research and development (R&D). Having one prototype in Indonesian Aerospace is essential as the plane can be used for real fighter development. In Aerospace engineering that plane is named as test bed plane (experimental).

7. Some of knowledge and experience gathered in KF21/IFX program is also used for MALE UCAV Elang Hitam (Black Eagle) development program.

This is my take from my connection to the Indonesian senior engineer from KFX/IFX program.
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Indonesia delays payment for S. Korea's fighter development project​

Oh Seok-min

All News11:49 October 07, 2019

As of July, 114 Indonesian engineers were sent to South Korea to work with Korea Aerospace Industries Co. (KAI), the country's sole aircraft manufacturer, to design and make a prototype of the fighter, according to a DAPA official.

Last month, DAPA confirmed that the design for the combat jet met all military requirements, allowing the project to go on to the next phase of constructing a prototype.

The prototype will be ready in the first half of 2021, and the agency is eyeing 2026 for the completion of development, which began in 2016, according to DAPA.

Moeldoko Meets with DAPA Republic of Korea to Discuss Continuation of Combat Aircraft Cooperation


Chief of Presidential Staff, General TNI (Ret.) Dr. Moeldoko met with the Minister of Defense Acquisition Program Administration (DAPA) of the Republic of Korea (South Korea), Eom Dinghwan, at the Bina Graha building, Jakarta, Thursday (5/10).


Jakarta – Chief of Presidential Staff, General TNI (Ret.) Dr. Moeldoko, met with the Minister of Defense Acquisition Program Administration (DAPA) of the Republic of Korea (South Korea), Eom Dinghwan, at the Bina Graha building, Jakarta, Thursday (5/10).

The meeting discussed the continuation of cooperation in developing the Korean Fighter X and Indonesian Fighter X (KFX/IFX) fighter aircraft. Moeldoko said that cooperation in developing the KFX/IFX fighter aircraft continues.

Defense industry cooperation, he said, is very important for Indonesia's relations with South Korea, which is entering its 50th year this year."The President's direction is to continue cooperation, because this is strategic cooperation. "Both for long-term defense infrastructure development and the transfer of technological knowledge," he said.

As is known, the implementation of the KFX/IFX fighter aircraft collaboration is under the coordination of the Coordinating Ministry for Political, Legal and Security Affairs (Kemenkopolhukam), and the Ministry of Defense (Kemhan). In this collaboration, Indonesia will receive the transfer of fighter aircraft technology.

This project is estimated to produce 120 fighter aircraft for South Korea, and 48 units for Indonesia. Moeldoko also said that the Indonesian government through the Presidential Staff Office, Ministry of Defense, Ministry of Finance and TNI continues to look for breakthroughs so that cooperation in developing the KFX/IFX fighter aircraft can continue.

Meanwhile, the Minister of Defense Acquisition Program Administration (DAPA) of the Republic of Korea (South Korea), expressed his appreciation for the Indonesian government's commitment to continuing cooperation in developing the KFX/IFX fighter aircraft.

“This is in line with the agreement between the leaders of the two countries, that Indonesia and Korea are the best partners. "Thank you to the Indonesian government for the continuation of this collaboration (KFX/IFX fighter aircraft)," said Eom Dinghwan.

Indonesian Air Force Commander visited Korea Aerospace and present in ADEX 2023 exhibition in South Korea. Second picture is Indonesian Air Force high level officers taking picture with two Indonesian KF21/IFX test pilots.



KF21/IFX during ADEX Exhibition in South Korea, October 2023


Indonesia remains committed to continuing KFX/IFX cooperation with Korea

Jumat, 27 Oktober 2023 21:53 WIB

The Indonesian Ministry of Defense stated that it remains committed to continuing cooperation in developing the KFX/IFX fighter aircraft with South Korea.

“This is cooperation between countries and a national priority program. "As for the state program, whoever the government is, it must continue," said the Director of Defense Technology and Industry, Directorate General of Defense Potential, Ministry of Defense, First Marshal TNI Dedy Laksmono in a workshop organized by the Foreign Policy Community of Indonesia (FPCI) in Jakarta, Friday.

He made this statement in response to the issue of stalled payments on Indonesia's cost share commitment for the KFX/IFX project, even though according to the initial agreement in 2014 Indonesia was charged 20 percent of the total cost of developing the fighter aircraft.

Meanwhile, 60 percent of the total cost of the project worth 8.8 trillion won or Rp. 100 trillion is the responsibility of the Korean government, and 20 percent comes from the aircraft manufacturing company Korea Aerospace Industries (KAI).

Dedy admitted that the limitations of the State Revenue and Expenditure Budget were an obstacle in paying Indonesia's cost-share, which reached around IDR 14 trillion until 2026 for the development, engineering and manufacturing phases.

According to him, the Ministry of Defense is only able to allocate around IDR 1.5 trillion per year for contributions to the development of KFX/IFX, an amount that is far from enough to pay Indonesia's obligations.
"For our budget at the Ministry of Defense, this obligation is very difficult. We have proposed increasing the budget, but the Minister of Finance said it was not possible," said Dedy.

Therefore, the Indonesian and Korean governments are still negotiating to find a solution to this problem. "In the future, we hope to be able to fulfill this obligation. Because we are also embarrassed, it seems like we have agreed but in the process it won't happen because there are APBN limitations," said Dedy.

Meanwhile, KAI Indonesia Office Chief Representative Officer Woo Bong Lee said that the Korean side had allocated as much funds as possible to continue the KFX/IFX project.

“We have increased the budget as much as we can get, even by borrowing money from the bank. "Now we are waiting for the money to come from the Indonesian side," said Lee.

He hopes that the governments of the two countries can immediately find a middle way to overcome this funding obstacle, so that the partnership between Korea and Indonesia can continue to be maintained.

“In our opinion, the Korean government will not take a bad decision on this issue. "And as far as I know, the Korean and Indonesian governments are still discussing this issue to find the best solution," he said.

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Indonesian gov has already set aside budget for its cost share payment for next year in 2024, much bigger than previous cost share payment in 2022 and 2023.

Source : my connection on the KFX/IFX team.
DAPA, reports of ‘KF-21 development cooperation with UAE’ are “unfounded”

However, after paying only KRW 227.2 billion as of January 2019, the contribution was not paid for nearly 4 years due to budget shortages, and only an additional payment of KRW 9.4 billion was made in November of last year and about KRW 41.7 billion in February of this year.

41.7 billion KRW = 30 million USD

Now latest news saying that Indonesia will pay 1.25 trillion Rupiah next year = 79 million USD which is more than double previous cost share payment in February 2023.


Rupiah is currently under pressured

PS : Until now there is no additional Rafale order after the 26 planes being ordered, and Finance Minister hasnt approved F15 EX order proposed by Prabowo for around 8 planes. I dont think we are going to order any F15 EX, President has already criticized Prabowo acquisition program.

Indonesia order of Rafale is using long term loan and it is strategically important to not too dependent on US fighters as we got embargoed from US in the past that made we have to grounded many of our Hercules and F16 during early 2000's. KF21 is still using critical US components like F414 engines. Rafale order is basically replacing previous acquisition plan to order SU35 from Russia, under current situation it is difficult to order Russian fighter, so we replace it with Rafale from France that is currently having strategic partnership with Indonesia.
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This is the presentation made by former Indonesian Airforce personnel (retired) who contributed in TD phase (2011-2013). The diagram shows 2011-2016 because Indonesia continue the development in Indonesia during 2013-2016 while Korea may also continue the development from 2013-16.

From 2013-2016 actually there is no joint research held in one place like happening during 2011-2012 December, this is because South Korean halt the funding for several years.

From the diagram, it is shown that during the TD phase, there are 52 Indonesian engineers involved, TD phase based on diagram started from 2011-2016. The result one of them is C103 design that become the basis of KF21 design.

NB: The program has been set by South Korea from 2002, but there is no real development happening until Indonesia joined the program in 2009 (MOU), 2010 (Contract), and 2011 (the start of join development)


This is the statement stated by Mr Erriss, I need to correct him since the cost share payment has been started being paid by Indonesia since 2022 November, and then followed in February 2023. Before November 2022 cost share payment, Indonesia also made its cost share payment in full in 2019 after not paying for two years (2017 and 2018). EMD phase started in 2016.

-Starting next year Indonesia will continue payments of 1.4 T
-Indonesia needs a strong commitment (Cost Share) to catch up, KAI promises to help accelerate Indonesia's lag

-Involvement of Indonesian test pilots in the KFX Program is very minimal
-The incomplete completion of the technology export permit process has an impact on sending prototypes to Indonesia
-ToT, more towards Knowledge Transfer, regarding the development of fighter aircraft
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Saying Indonesian delaying cost share payment is not true. Indonesia still has another 3 years to complete the payment and it has started paying again since 2022. Next year the budget has already been prepared as well.

Current gov will only have next year as their final year, impossible for them to make cost share payment until its completion. That is the duty of new administration to complete Indonesia cost share payment.

Unlikely new gov to dump this project, but many foreigners I see dont like to see Indonesia participation on this project, we can see on the writing of those journalists and how they keep trying to hide Indonesia engineering contribution on this program.
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Impact on Indonesian Economy


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