Studying an engine that was destroyed by a bird years ago, David Knauer, left, assists Brad Bianchi during the 361st Training Squadron’s Jet Engine Mishap Investigation Course at Sheppard AFB, Texas. Knauer, a course instructor, and others teach the nine-day course to help develop investigative techniques to those who could potentially be part of an accident investigation board. Bianchi is a quality assurance inspector for the 75th Propulsion Maintenance Group at Tinker AFB, Okla. (U.S. Air Force photo/John Ingle)