C-21 Maintenance
1st Lt. Christopher Stewart, 458 Airlift Squadron C-21A Pilot, runs through a preflight checklist to verify that the C-21A is ready and capable of performing its mission March 18, 2015. The C-21As provide first-class Operational Support Airlift and Aeromedical Evacuation with time, place, and mission sensitive requirements. (U.S. Air Force photo/Senior Airman Joshua Eikren)