With the development of construction industry. the traditional manual inspection has been gradually eliminated due to many shortcomings. such as low efficiency. time-consuming and labor-intensive. https://www.spidertattooz.com/Messerschmitt-Me262A-1A-Fighter-Aircraft-LT-Walter-Hagenah-III-Jagdeschwader-7-Larz-Airfield-Germany-1945-German-Luft/