Narrative:

I was passing through 3000 ft MSL and hit turbulence/windshear and the emergency exit came open on the pilot side. There was a loud bang in the aircraft and I felt the pressure change. I advise ATC and declared an emergency. ATC started to give me vector for the approach. On radar vector for the ILS runway 17, I lost 500 ft of my assigned altitude from power that was reduced and setting up for the approach. I had the approach for runway 9R set up. Then ATC changed the approach to ASR 17 and I came in to VFR conditions, canceled the emergency and landed the plane safely. The hook that holds the window failed.

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Original NASA ASRS Text

Title: PLT OF AN ATX BEECH BE58 BARON DECLARED AN EMER AND RETURNED TO LAND AFTER THE EMER EXIT WINDOW BLEW OFF THE ACFT IN TURB DURING DEP CLB.

Narrative: I WAS PASSING THROUGH 3000 FT MSL AND HIT TURB/WINDSHEAR AND THE EMER EXIT CAME OPEN ON THE PLT SIDE. THERE WAS A LOUD BANG IN THE ACFT AND I FELT THE PRESSURE CHANGE. I ADVISE ATC AND DECLARED AN EMER. ATC STARTED TO GIVE ME VECTOR FOR THE APCH. ON RADAR VECTOR FOR THE ILS RWY 17, I LOST 500 FT OF MY ASSIGNED ALT FROM PWR THAT WAS REDUCED AND SETTING UP FOR THE APCH. I HAD THE APCH FOR RWY 9R SET UP. THEN ATC CHANGED THE APCH TO ASR 17 AND I CAME IN TO VFR CONDITIONS, CANCELED THE EMER AND LANDED THE PLANE SAFELY. THE HOOK THAT HOLDS THE WINDOW FAILED.

Data retrieved from NASA's ASRS site as of July 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.