Complex sentence: The Valkyrie entered an uncontrollable spin and crashed into the ground north of Barstow, California, killing co-pilot Carl Cross, and its pilot, Alvin White, one of Walker's colleagues from the Man In Space Soonest program, ejected and was a sole survivor.
Split into simpler sentences: The Valkyrie entered an uncontrollable spin and crashed into the ground north of Barstow, California, killing co-pilot Carl Cross. Its pilot, Alvin White, one of Walker's colleagues from the Man In Space Soonest program, ejected and was a sole survivor.