Narrative:

Passenger door opened in-flight, creating a tornado in the cockpit. Declared an emergency because I was too distraction to navigation or see- and-avoid VFR traffic (also couldn't hear well because of noise and unsure if I could maintain course and altitude at first). Immediately headed for the nearest runway (with ATC approval). Canceled IFR and emergency status after slowed down and cockpit under control. Landed uneventfully. Could not close door in-flight regardless of door/windows/vents/sideslip confign. I closed the door but failed to latch it before takeoff. I think it was just a case of leaving out a step inadvertently. I was in a hurry. The airplane had developed a rapid fuel leak while sitting in a hangar, untouched, for 6 days. Defueling and safetying the fuel tank and replanning the flight ate my time cushion. The door was amazingly 'draggy.' it took about 90% power to fly level with gear and flaps down. It was enough to make me restrict bank angles in setting up final approach.

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Original NASA ASRS Text

Title: PLT DECLARES EMER AFTER ACFT DOOR OPENS INFLT IN DFW AIRSPACE.

Narrative: PAX DOOR OPENED INFLT, CREATING A TORNADO IN THE COCKPIT. DECLARED AN EMER BECAUSE I WAS TOO DISTR TO NAV OR SEE- AND-AVOID VFR TFC (ALSO COULDN'T HEAR WELL BECAUSE OF NOISE AND UNSURE IF I COULD MAINTAIN COURSE AND ALT AT FIRST). IMMEDIATELY HEADED FOR THE NEAREST RWY (WITH ATC APPROVAL). CANCELED IFR AND EMER STATUS AFTER SLOWED DOWN AND COCKPIT UNDER CTL. LANDED UNEVENTFULLY. COULD NOT CLOSE DOOR INFLT REGARDLESS OF DOOR/WINDOWS/VENTS/SIDESLIP CONFIGN. I CLOSED THE DOOR BUT FAILED TO LATCH IT BEFORE TKOF. I THINK IT WAS JUST A CASE OF LEAVING OUT A STEP INADVERTENTLY. I WAS IN A HURRY. THE AIRPLANE HAD DEVELOPED A RAPID FUEL LEAK WHILE SITTING IN A HANGAR, UNTOUCHED, FOR 6 DAYS. DEFUELING AND SAFETYING THE FUEL TANK AND REPLANNING THE FLT ATE MY TIME CUSHION. THE DOOR WAS AMAZINGLY 'DRAGGY.' IT TOOK ABOUT 90% PWR TO FLY LEVEL WITH GEAR AND FLAPS DOWN. IT WAS ENOUGH TO MAKE ME RESTRICT BANK ANGLES IN SETTING UP FINAL APCH.

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.