What was found
DISCOVERED VERY HEAVY EXFOLIATION CORROSION ON ALUMINUM SEAT BELT ATTACH "D" RING AT FUSELAGE ATTACH POINT. CORROSION WAS HIDDEN UNDERNEATH BELT WEBBING. AREA IS PRONE TO DAMPNESS AND IS HIDDEN FROM VIEW. CAN ONLY BE SEEN BY PUSHING SEWN AREA OF BELT BACK WHERE IT ATTACHES TO RING. BELT DEPARTED AIRFRAME WHEN SUBJECTED TO A SHARP PULL. FOUND 2 BELT ENDS LIKE THIS. SUGGEST STEEL ATTACH RINGS VICE ALUMINUM. AND PRYING BACK BELT TO INSPECT "HIDDEN" AREA WHERE SEWN LOOP OF BELT JOINS ATTACH RING.