Narrative:

Captain's windshield was loose and upon descent a loud squeal (approximately 100 DB) started at FL200 and continued until 10,000' or so (4 psi different pressure). Could not determine location of noise at first. I put in ear plugs (yellow sponge) and was able to hear ATC. Noise was so loud F/a's reported you could hear it to tail of aircraft with cockpit door closed. Was very difficult to fly with the loud noise and intra-cockpit communication was available only on interphone. Noise stopped and subsequent approach and landing was normal. Maintenance advised me the windshield needed to be retorqued and seated.

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Original NASA ASRS Text

Title: WINDSHIELD AIR LEAK CAUSES COCKPIT AND ATC COM DIFFICULTIES FOR MLG FLT CREW.

Narrative: CAPT'S WINDSHIELD WAS LOOSE AND UPON DSCNT A LOUD SQUEAL (APPROX 100 DB) STARTED AT FL200 AND CONTINUED UNTIL 10,000' OR SO (4 PSI DIFFERENT PRESSURE). COULD NOT DETERMINE LOCATION OF NOISE AT FIRST. I PUT IN EAR PLUGS (YELLOW SPONGE) AND WAS ABLE TO HEAR ATC. NOISE WAS SO LOUD F/A'S REPORTED YOU COULD HEAR IT TO TAIL OF ACFT WITH COCKPIT DOOR CLOSED. WAS VERY DIFFICULT TO FLY WITH THE LOUD NOISE AND INTRA-COCKPIT COM WAS AVAILABLE ONLY ON INTERPHONE. NOISE STOPPED AND SUBSEQUENT APCH AND LNDG WAS NORMAL. MAINT ADVISED ME THE WINDSHIELD NEEDED TO BE RETORQUED AND SEATED.

Data retrieved from NASA's ASRS site as of August 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.