KANDAHAR AIRFIELD, Afghanistan (June 22, 2011) - Pfc. Johnathan Hudson (far left), an AH-60D Apache helicopter crew chief with Troop D, Task Force Palehorse (7th Squadron, 17th Cavalry Regiment), secures the base of a blade needing replacement as Pfc. Valentine Hendrickson (center) and Pfc. Luke Yetter, also AH-60D Apache crew chiefs with Troop D, TF Palehorse, attach the blade to a crane here June 22. Many helicopter maintainers strive to advance to crew chiefs and eventually advance farther.