Narrative:

During cruise, the copilot door popped open. In addition, my charts flew out the door with the checklist. The frequency was busy and I noticed a broken layer below. I initiated a descent into VFR conditions and was about 200-300 ft below my assigned altitude before I was able to cancel IFR. I stayed on my transponder code and in 2-WAY contact with approach and then chino tower. The descent and landing were uneventful. No emergency was declared. It was very difficult to hear ATC and the door created a considerable amount of drag.

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Original NASA ASRS Text

Title: A BE59 PLT DIVERTS TO ALTERNATE AFTER HIS PAX DOOR CAME UNLATCHED. HE LOST HIS CHARTS AND CHKLIST. RPTR ALSO CREATED AN ALTDEV.

Narrative: DURING CRUISE, THE COPLT DOOR POPPED OPEN. IN ADDITION, MY CHARTS FLEW OUT THE DOOR WITH THE CHKLIST. THE FREQ WAS BUSY AND I NOTICED A BROKEN LAYER BELOW. I INITIATED A DSCNT INTO VFR CONDITIONS AND WAS ABOUT 200-300 FT BELOW MY ASSIGNED ALT BEFORE I WAS ABLE TO CANCEL IFR. I STAYED ON MY XPONDER CODE AND IN 2-WAY CONTACT WITH APCH AND THEN CHINO TWR. THE DSCNT AND LNDG WERE UNEVENTFUL. NO EMER WAS DECLARED. IT WAS VERY DIFFICULT TO HEAR ATC AND THE DOOR CREATED A CONSIDERABLE AMOUNT OF DRAG.

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.