North Korea’s sinking of the ROKS Cheonan is causing South Korea to rethink its planned Defense Reform 2020 restructuring and procurement program. Among other changes the Navy could see a shift toward more FFX type light patrol frigates.
This new class of Frigate will replace +/- 37 olders warships (nine 2300 tons Ulsan class corvettes, twenty fourth 1200 tons Pohang class light corvettes, Fourth 1000 tons Dong Hae class light corvettes), build during early 1980's.
Usually this new class of frigate will be much bigger (3200 tons), better armed (a 76 or more likely a 127mm gun, a CIWS system, one helico with hangar) and build in smaller number (likely +/- 18/24 new ships to replace 37 olders).
With the recent "Chenoan disaster" It is clear that the South Korean Navy will try to integrate in these new vessels a stronger anti submarine capability. But unfortunately the current design does not include missile VLS for Red Shark ASW missile. Since the first ship of this series is scheduled for 2012, it is very likely that the first "batch"of 6 vessels (to be commissioned in 2012-2015) will have the original design.
A possible second "batch" (12/24 vessels ? between 2015/2022), probably benefit from greater improvements (superstructures modified, maybe slightly enlarged with a "pluggin" few hull meters added, to more easily incorpore VLS).