Today's aircraft are generally leased, and new aircraft can only be inspected after the flight. If it has problems, replace it. When it is returned to the manufacturer, it should be fully repaired and all parts should be replaced with new ones. 25015 flight hours for inspection A, 4000+200 hours for inspection C and 32000 flight hours or eight years for inspection D, whichever comes first. Besides, I have never heard of B-ultrasound …