Tech. Sgt. Travis Kidwell, 40th Helicopter Squadron UH-1N Iriquois flight engineer, calculates take-off and landing data using charts to update a TOLD data card July 6, 2016, near Malmstrom Air Force Base, Mont. Flight engineers update the data when the environment changes because it can affect the performance of the helicopter. (U.S. Air Force photo/Staff Sgt. Delia Marchick)