Narrative:

Earlier that evening another pilot had written up 2 discrepancies in the aircraft log. 1 was a flat tire (right main gear), and the other was a faulty cabin door warning system. A company mechanic made repairs, and signed off. He and I were both satisfied that both items had been fixed. After takeoff while climbing on an approximately heading of 250, my destination being teb (teterboro, nj), and at a point roughly 10 NM away from hfd, the cabin door warning light came on. Very shortly thereafter, I heard a loud noise. Papers started to rustle in the right seat. My headset was no longer on my head. I looked to my left and could not see the cabin door. I suspected that the door had separated from the door frame. I moved the throttles and the flight controls and they seemed to work normally. I put the headset back on and told the controller that I wanted to return to bradley (bdl, bradley international airport), that I had lost my cabin door, and that I had better call it a mayday. I then made a normal landing at bdl on runway 24. I taxied to my usual parking area and shut down the engines without incident.

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Original NASA ASRS Text

Title: DOOR OF SMT ACFT DEPARTED THE AIRFRAME IN CLB AT APPROX 4000 FT. PLT ELECTED TO RETURN TO BDL ARPT.

Narrative: EARLIER THAT EVENING ANOTHER PLT HAD WRITTEN UP 2 DISCREPANCIES IN THE ACFT LOG. 1 WAS A FLAT TIRE (R MAIN GEAR), AND THE OTHER WAS A FAULTY CABIN DOOR WARNING SYS. A COMPANY MECH MADE REPAIRS, AND SIGNED OFF. HE AND I WERE BOTH SATISFIED THAT BOTH ITEMS HAD BEEN FIXED. AFTER TKOF WHILE CLBING ON AN APPROX HDG OF 250, MY DEST BEING TEB (TETERBORO, NJ), AND AT A POINT ROUGHLY 10 NM AWAY FROM HFD, THE CABIN DOOR WARNING LIGHT CAME ON. VERY SHORTLY THEREAFTER, I HEARD A LOUD NOISE. PAPERS STARTED TO RUSTLE IN THE R SEAT. MY HEADSET WAS NO LONGER ON MY HEAD. I LOOKED TO MY L AND COULD NOT SEE THE CABIN DOOR. I SUSPECTED THAT THE DOOR HAD SEPARATED FROM THE DOOR FRAME. I MOVED THE THROTTLES AND THE FLT CTLS AND THEY SEEMED TO WORK NORMALLY. I PUT THE HEADSET BACK ON AND TOLD THE CTLR THAT I WANTED TO RETURN TO BRADLEY (BDL, BRADLEY INTL ARPT), THAT I HAD LOST MY CABIN DOOR, AND THAT I HAD BETTER CALL IT A MAYDAY. I THEN MADE A NORMAL LNDG AT BDL ON RWY 24. I TAXIED TO MY USUAL PARKING AREA AND SHUT DOWN THE ENGS WITHOUT INCIDENT.

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.