The U.S. Air Force is investigating the crash of a C-21, the military version of the Learjet 35, the afternoon of February 2. The pilot and copilot–the only occupants–were killed when the jet crashed into a field near Ellsworth Air Force Base near Rapid City, S.D., seconds after takeoff. Air Force investigators said witnesses saw the jet depart the base, turn back sharply and then crash nearly upside down. The C-21 is used to transport people and cargo, and this aircraft was based at Wright-Patterson Air Force Base in Ohio. Because the crash involved a military aircraft, the NTSB has no jurisdiction to investigate.