Study on effect of ultrasonic inspection criteria to soundness evaluation of honeycomb core sandwich and laminate structure used for commercial aircrafts

초음파검사 판정 기준이 항공기용 복합구조재의 건전성 평가에 미치는 영향에 관한 고찰

The soundness of honeycomb core sandwich and laminate structure used for commercial aircrafts is generally evaluated with ultrasonic inspection because the inspection is most sensitive to planar surfaces which are perpendicular to sound propagation pass and reflects sound almost 100％ to equipment. And most defects inherent in composite material curing process has good reflective surfaces. With all this advantage, unexpected obstruction to product and additional cost could be occurred when inappropriate accept/reject criteria is given. In this study the importance of inspection criteria will be discussed to show how inappropriate criteria cause unexpected results leading to high production cost and how much time must be spent to correct those improper criteria with an actual case occurred in Aerospace Division, Korean Air.