What was found
(CAN) IT WAS OBSERVED ON ONE OCCASSION THE WINDSHIELD APPEARED TO BE MOVING IN ITS LOWER RETAINER DURING WATER LANDINGS. MAINTENANCE ACTION INVOLVED REMOVING LOWER RETAINER REVEALING FORWARD DOOR POSTCHANNEL WAS CRACKED THREE INCHES. AT CRACK LOCATION, THERE IS AN .1250 INCH PRODUCTION GAP BETWEEN LOWER SKIN P/N 1213600-25 AND VERTICAL OUTER RETAINER P/N 0713611-3. RIGIDITY OF UPPER CABIN BOX IS LOST. IT IS FELT THIS CONDITION COULD LEAD TO MORE SERIOUS PROBLEMS. SUSPECT CAUSE DUE TO HEAVY LANDINGS AND HIGH FREQUENCY CYCLES.