The Estonian Centre for Defence Investment has signed a contract with a total volume of €36 million to acquire an additional twelve K9EST Kou (Lightning) self-propelled howitzers from South Korean arms manufacturer Hanwha Aerospace. The first self-propelled artillery units of this type arrived in Estonia in 2020. The initial contract involved the procurement of 24 self-propelled howitzers for Estonia but a decision was subsequently made to acquire 12 more K9 Thunders, the final delivery of which should take place in 2026. Training on the use of K9 Thunders for representatives of the Estonian Defence Forces began in South Korea in September 2020. The defence forces now have its own instructors, under whose supervision, training of the first groups of reservists has taken place.
In 2021, the Estonian Centre for Defense Investment signed a framework agreement with the company Go Craft for the modification and reconstruction of 24 self-propelled howitzers, which is a part of the process of integrating the units with the systems of the Estonian Defence Forces. Go Craft, in cooperation with the Defence Forces and K9 manufacturer Hanwha Techwin, have developed two prototypes for the self-propelled howitzers which have successfully completed a test period in the Defence Forces. The works to be carried out include the installation of communication and control systems, painting, replacement of the fire extinguishing system, adaptation of the electrical system and the installation of additional accessories.
Estonia was invited by Finland in teaming up for the procurement of the K9, to reduce the purchase cost for both nations. Benefitted by group buying, the test data of the K9 was provided and shared to Estonia by Finland, with approval from South Korea. Estonia is expected to purchase 12 K9s for $50 million. Hanwha will supply 12 used K9s, including maintenance parts and training for €46 million, a similar contract to that of Finland. In August 2021, the Estonian Centre for Defense Investment (RKIK) signed €4.6 million contract with Hanwha Defense and Go Craft in modernizing 24 K9EST Kou, hinting at purchasing 6 more for its inventory. The upgrade involves communication systems, a FCS, painting, fire suppression system, and electronics.
The K9 Thunder is a South Korean 155 mm self-propelled howitzer designed and developed by the Agency for Defense Development and civil contractors including Dongmyeong Heavy Industries, Kia Heavy Industry, Poongsan Corporation, and Samsung Aerospace Industries for the Republic of Korea Armed Forces, and is now manufactured by Hanwha Aerospace. K9 howitzers operate in groups with the K10 automatic ammunition resupply vehicle variant. The entire K9 fleet operated by the ROK Armed Forces is now undergoing upgrades to K9A1, and a further upgrade variant K9A2 is being tested for production. As of 2022, the K9 series has had a 52% share of the global self-propelled howitzer market, including wheeled vehicles, since the year 2000.