Characterizing aircraft material, coating, and systems in the field to determine material coating defects is necessary to ensure operational integrity of the aircraft. Current manual methods for inspecting the external surface of low-observable (LO) aircraft are time consuming and prone to error. IAI and collaborators will continue developing EX-SCAN, an autonomous non-contact optical inspection system that can detect, register, and characterize defects in external coatings of aircraft. A functional, scaled prototype of an inspection robot to scan a scaled model aircraft has been developed, along with initial image processing algorithms. A study on the feasibility of scanning a full-size aircraft has also been conducted. The key innovation of EX-SCAN is the integration of a self-localizing mobile robot equipped with an array of cameras and corresponding software to ensure rapid, autonomous, 100% coverage of the aircraft outer mold line (OML). The team will refine the system by adding autonomous mobility and navigation, and enhancing the defect processing software. Focus areas will include enhancing the localization technology, expanding defect detection, coordinating defect registration technology with movable cameras and localization software, improving characterization technology, and integrating these capabilities into a cohesive system. EX-SCAN can accurately estimate in real time the position and orientation of the defect, and provide in-situ optical identification and high-resolution characterization of the defected area. It will transmit defect location and characteristics to the aircraft health assessment system to aid with defect analysis and part life tracking. EX-SCAN reduces inspection times and minimizes human error, thus increasing assessment reliability and aircraft availability while reducing maintenance costs.