Beneath the cracks Published Feb. 10, 2015 By Airman 1st Class Deana Heitzman 31st Fighter Wing Public Affairs AVIANO AIR BASE, Italy -- U.S. Air Force Senior Airman Jon Zengotita, 31st Maintenance Squadron non-destruction inspection journeyman, inspects an F-16 Fighting Falcon ejection seat handle for cracks, Feb. 10, 2015, at Aviano Air Base, Italy. After fluorescent oil is poured on a part, it attaches to any cracks and can be seen when a magnetic field is placed on either end of the part. This method allows Airmen to inspect parts without destroying or damaging a product or material. NDI is responsible for testing the integrity of aircraft parts before they become a potential hazard. (U.S. Air Force photo by Airman 1st Class Deana Heitzman/Released)