In 2004, Boeing began the final assembly of the first F-15K Strike Eagle fighter aircraft for the Republic of Korea Air Force (ROKAF). During final assembly in St. Louis, the F-15K forward, center, and aft fuselage assemblies were joined, followed by the wing assemblies. The F-15K is an advanced derivative of the U.S. Air Force F-15E, the world's most capable long-range, multi-role fighter. It can perform air-to-ground and air-to-air missions during the day or at night, in virtually any weather. It can carry more than 23,000 pounds of payload, reach Mach 2.5, and incorporates the latest military technologies. These include the APG-63(V)1 radar, a third-generation forward looking infrared system, a helmet-mounted cueing system, and weapons-control systems that support advanced weapons such as the Joint Direct Attack Munition, or JDAM, Standoff Land Attack Missile-Expanded Response, or SLAM-ER, Advanced Medium Range Air-to-Air Missile, or AMRAAM, and AIM-9X Sidewinder missile.