SEYMOUR JOHNSON AIR FORCE BASE, N.C. --   The 336th Aircraft Maintenance Unit crew chiefs perform daily inspections on F-15E Strike Eagles. The crew chiefs conduct two different types of inspections, a thru-flight and a basic post flight. A thru-flight inspection occurs between flights if a jet is flying twice in a single day. A BPO inspection occurs at the conclusion of a flying period. It is. The technical order's provide Airmen with step-by-step maintenance instructions, which is mandatory for all Airmen to follow during every inspection.