North Korea has stepped up the number of training flights since last month to as many as 650 sorties a day. The North Korean air force is conducting training flights even on weekends, several times flying so far down south near the border with South Korea that the South had to scramble fighter planes to form defensive formations.
A government source here said Wednesday, "We're analyzing the reasons for the marked increase in North Korean sorties compared to its usual winter training flights, focusing on the fact that they have increased after North Korean leader Kim Jong-un inspected air force bases in January."
The South Korean and U.S. military believe North Korea is using up almost twice as much fuel than usual for the increased number of training flights and are looking into whether the North is tapping into fuel stockpiled for wartime.
Military sources said the North Korean air force conducted less than 100 sorties a day on average until last year and no more than 300 to 400 a day even during the winter months, when the North Koran military normally conducts intensive training exercises. That was still far behind the average of 700 to 800 sorties on per day by the South Korean Air Force.
Since the 1990s, the highest number of daily sorties by the North's air force was 450 to 500, but now that has risen to 650. A military source here said, "It costs W2-3 million each time to fly an F-16 fighter jet (US$1=W1,136). We don't know exactly how much the North Korean military is paying extra for the increased training flights, but the costs must have increased significantly."
As North Korea recently conducted several training flights on weekends, South Korean fighter jets had to be on the alert at all times.
One notable development related to the increased sorties is to do with the whereabouts of the young North Korean leader. In January this year, Kim Jong-un visited eight military installations, and half of them were air bases. One of them houses an elite squadron that operates a relatively advanced Russian MiG-29 fighter jet. North Korean authorities revealed a photo of Kim and unit members posing in front of a MiG-29, providing intelligence here with their first up-close image of the jet.
Some experts believe North Korean pilots appealed to Kim during his visit about the gap in the number of sorties between the North and South, and Kim authorized additional training flights to gain the support of the military, despite the heavy cost. The pilots then apparently conducted sorties even on weekends to demonstrate their loyalty to Kim.
Others say the increased sorties are a response to the South vowing recently to thwart any North Korean provocations by mobilizing its state-of-the-art F-15K fighter jets. Experts say this is probably why the North, during a massive military drill held recently in front of Kim, also deployed its MiG-29 fighter jets, as well as SU-25 close-air-support jets designed to destroy tanks and IL-28 bombers.
A government official here said, "We can't rule out that North Korea is stepping up training to carry out provocations, so we are increasing our readiness."