Concerns are escalating over a possible airpower vacuum in South Korea as the country’s warplane acquisition is not faring well with difficulties in procuring key technologies from the U.S. and the aging fighter fleet.

Last week, Washington reiterated its position against Seoul’s call for the technological transfer, foreshadowing a potential delay in Seoul’s ambitious project to develop an indigenous fighter jet, which is already more than a decade behind schedule.

For the South’s Air Force, the project, called KF-X, is a crucial initiative to maintain an adequate level of fighters to execute peacetime and wartime missions to deal with possible North Korean aggression and provocations.

Air Force officials say that according to the analysis by the state-run Korea Institute for Defense Analyses, the appropriate number of fighter jets to keep the airpower initiative in the early phase of a potential war is 430 -- some 100 high-end fighters, 200 middle-end fighters and 130 low-end fighters.

The high-end fighter refers to the F-35-class stealth warplane, while the middle- and low-end fighters refer to KF-16-class aircraft and FA-50 light attack aircraft, respectively.

Currently, the South has some 420 fighters, with some officials saying the Air Force has already begun suffering from the shortage of warplanes. The North is said to possess some 820 warplanes, though their planes are mostly based on old platforms.

One of the most urgent issues facing the Air Force is the aging of its fleet of F-4s and F-5s deployed four decades ago.

“The shortage of warplanes means that there could be a delay in executing a wartime mission, which could result in huge damages for our nation should any conflict break out here and be protracted,” a security expert told The Korea Herald, declining to be named.

“Now, there have been moves to delay the decommissioning of the F-4s and F-5s. But think about how Air Force personnel would feel while operating the old platforms that should be phased out, while other nations are flying top-end warplanes.”

The Air Force plans to decommission some 40 F-4s by the end of 2019. It will also decommission some 120 F-5s by 2019 and another 60 F-5s by 2025.

The government currently plans to introduce 60 FA-50 light attack planes and 40 F-35s. But in the mid-2020s, the total number of the South’s warplanes is expected to be around 310, should it decline to purchase additional fighters.

With technical challenges, observers expressed doubts over whether the South can carry out the KF-X program as planned.

The KF-X program, which includes both the development and production of the home-built warplane, is expected to cost nearly 20 trillion won ($17.7 billion). Under the project, Seoul seeks to deploy 120 fighters after 2023 to replace its aging fleets of F-4s and F-5s.

By Song Sang-ho(sshluck@heraldcorp.com)