Korean Air suspended about 53 percent of scheduled flights. Cancellations were set to increase to 63 percent of the total, the airline said. The majority of the pilots are unionized. Some in the South Korean government are calling for the Ministry of Labor in intervene and force the striking pilots back to work. Last August, KAL's smaller rival Asiana Airlines had a similar situation, and then the government stepped in. So I bet that if they'd do it for Asiana, they'd certainly do it for Korean Air, which is seen as the 'flag carrier' of South Korea.
And now that figures are out saying that the strike costs the economy $200 million in exports every day (KAL has a large cargo division), I'm sure the government will certainly intervene. For its part, KAL will lose $25 million a day by its own estimate.