South Korea chose on Monday Korea Aerospace Industries Ltd , which expects to partner Lockheed Martin Corp (LMT.N), to develop a mid-level fighter jet that will cost around 8.7 trillion won ($7.88 billion). The Defense Acquisition Program Administration (DAPA) also confirmed its decision to upgrade South Korea’s Patriot missile system, with Raytheon Co (RTN.N) chosen to upgrade the launch systems. South Korea has been trying to bolster its arsenal in the face of a missile threat from North Korea.