South Korea’s Defense Acquisition Program Administration has announced that 20 more Lockheed Martin F-35 Lightning II Joint Strike Fighters will be procured under the second phase of its F-X3 program, due to be launched in 2021, when deliveries of the first batch of 40 are scheduled to be completed. These 40 original F-35As were ordered for the Republic of Korea Air Force (RoKAF) in 2014, and deliveries began in March 2019. Eight have now been delivered, and the RoKAF expects to have 13 by the end of the year and 26 by the end of 2020.

It remains uncertain as to which version of the Lightning II will be procured under the new phase of the program, which is valued at 4 trillion won ($3.35 billion). There were press reports that the National Security Office of the Blue House (the president's residence) had pushed the Air Force in April to consider purchasing the short-takeoff-and-vertical-landing F-35B, presumably to allow them to operate from the Navy’s two 14,500-tonne Dokdo-class amphibious assault ships, a planned 30,000-tonne carrier-type landing platform helicopter carrier, or more likely from a new class of aircraft carrier.

The Blue House immediately denied that it had tried to influence the F-35 purchase, pointing out that there was “a legal procedure for any procurement project.” The usual procedure is for the military to make a procurement request, which is then approved by the Joint Chiefs of Staff, reviewed by the Ministry of National Defense’s Defense Acquisition Program Promotion Committee before being handed off to the Defense Acquisition Program Administration to manage the project.

South Korean media has recently reported that the purchase of aircraft carriers is “under consideration” by the National Assembly’s National Defense Commission. It was reported that one option under consideration is a 70,000-tonne twin-island design with a length of 298 meters and a width of 75 meters, carrying 40 fixed-wing aircraft and eight helicopters. This is similar in size and configuration to the new 72,000-tonne British Queen Elizabeth class, which is 280 meters long. The other option reportedly being considered by South Korea is smaller—40,000 tonnes, 238 meters long and 62 meters wide—and is intended to embark an air wing composed of 20 fixed-wing aircraft and eight helicopters. This is broadly similar to the U.S. Navy’s 45,000-tonne America-class Landing Helicopter Assault ships, which can carry up to 20 USMC F-35Bs.

While these ship programs would indicate a Korean requirement for the F-35B, the state-funded Korea Institute for Defense Analyses (KIDA) suggested that the introduction of more F-35As might be “more feasible," while the RoKAF itself is understood to favor the F-35A, which has longer range, more weapons options, and a lower price tag than the STOVL variant, with price being the main factor. The F-35A is currently priced at about $89 million, while the F-35B costs $115 million.

Korea is the latest in a growing list of existing F-35 customers to have placed additional orders for the type. The Netherlands ordered nine more F-35As in October 2019, while Japan has announced its intention to buy additional F-35As, as well as 42 F-35Bs.