The beginning of serious Korean avioncs HW and SW development was through the offset ToT of F-16 source codes and documents, which were transferred through the KFP programme. Later, further technologies were obtained through the KTX-II programme, but most of them were aircraft structural design, analysis and evaluation, as well as programme management and system engineering related technologies. With the obtained F-16 softwares, ROKAF was able to support its KF-16 fleets with in-house codes, especially when integrating new weapons and simple avionic equippments.
Though, the real breakthrough was the F-X programme that followed KFP. There were total of 95 technologies transferred from US to Korea as an offset for the three separate F-X programmes :
- 30 technologies for the 1st F-X (40 F-15Ks)
- 40 technolgies for the 2nd F-X (21 F-15Ks)
- 25 technologies for the 3rd F-X (40 F-35As)
Not all of them were avionics related, but it undoubtedly significantly helped with Korean avionics development. Part of the technologies transferred through the first and second F-X are known to the public, which are :
- HMD design
- Mission computer design
- Data-link design
- Avionics embedded SW design
- Aircraft lighting and NVIS test and evaluation equippment design
- Interference blanking unit and radio frequency interference technology
- Fly-By-Wire design
- Steer-By-Wire design
- Integrated servo actuator design
For example, the FBW, SBW and integrated servo actuator design technology were the basis in developing indigenous FLCS, which was later demonstrated on the T-50 prototype. Indigenous mission computer with domestic software was also developed for use in the FA-50 variant. Before these technologies were transferred and Korean models were developed, the T-50 variants were equipped with FLCS and mission computers provided by LM in form of a black-box. First examples of T-50s equipped with Korean FLCS are known to be RTAF T-50THs. Data-link design technology was also extensively used to design various Korean TDL waveforms like KVMF and Link-K, as well as data link terminals and processors like TMMR and JTDLS. These systems are currently in use with ROKA, ROKN and ROKAF and is under constant development for wider application within the tri-service.
The development of EW related technologies in particular have a longer history of indigenous development, compared to other military electronics. The starting point was when LG precision (yes, that LG. Later spun-off into LiG group, and LiG NEX1) produced a domestic variant of the ARGO systems PHOENIX naval EW system for ROKN, which was called ULQ-11/12K. This was followed by the development of ALQ-88K/AK airborne SPJ pod, which was, again, largely based on the technology transferred from the US. Development of this airborne SPJ begun in 1987 and was concluded in 1992. This was later followed by a more advanced ALQ-200K system.
Although the Korean aerospace sector was able to learn various key technologies through US support and ToT provided by Boeing and LM as an offset for F-X programmes, EL of several key avionics technologies were not granted and thus had to be developed domestically, often with foreign assistance from other countries. These were mainly that of AESA radar and electro-optical systems like the IRST and FLIR, as well as system integration and data-fusion technologies.
Korean AESA development could be traced all the way back to 2006. The first step was research and development project of solid state transmitter/receiver that started in 2006 and concluded in 2009. This was a joint ADD-LIG Nex1 programme, as were multiple follow-up AESA radar programmes. Airborne AESA MFR demonstrator prototype development started in 2010 as a follow-up programme and was concluded in 2013. This was followed by two other demonstrator prototype development programmes and KF-X demonstrator radar development programme. So overall, it has been well over a decade since Korea started developing its first airborne AESA radar. In the meantime, there were also naval and ground-based passive and active phased array radars developed and put into service. Also notable are COTS spin-offs, since communications system based on GaN chips as well as phased array antenna design and control were becoming more and more ubiquotous in the civilian sector during these periods. Korea, especially Samsung Electronics has been a notable player in the mobile modem as well as communication SOC equippment market, though the military and other government institutions like ETRI were playing a key role in trailblazing Korean HEMT MMIC technology development; Korean civil sector have long relied on imported HEMT MMIC for use in their communication chips and equippments, so GaN and SiC chips developed through the civilian-military dual-use programmes funded by the government as well as private sector are one of the most notable civil-military collaboration programme within Korea. I'll provide details regarding the radar development later.
KF-21 IRST and FLIR technologies are based on naval and heliborne IRST and FLIR systems developed before KF-X. These are most notably the naval ASQ-540K and ASQ-600K systems, as well as AAQ-333 FLIR system. I will also provide more details in the future.
Overall, a lot of the technologies that went into KF-21 avionics has its roots in US and European ToT, which were either transferred/obtained through a license production programme, technical assistance programme, direct transfer of technolgy or through offset deals. Though, in further developing these technologies into a more advanced product that is the KF-21 avionics and other naval, airborne and ground-based military electronics systems in use and underdevelopment today in Korea, a sizeable investment, long-term planning and lot of effort were required. Also, several avionics technologies were developed through a spin-off from related naval and ground-based programmes and vice-versa.