NTSB Probable Cause

FAILURE OF THE PILOT TO MAINTAIN ADEQUATE AIRSPEED WHILE MANEUVERING BACK TO THE RUNWAY WHICH RESULTED IN AN INADVERTENTSTALL. CONTRIBUTING FACTORS WERE: FAILURE OF THE PILOT TO INSURE THE CABIN DOOR (ON THE PASSENGER'S SIDE) WAS PROPERLYCLOSED AND SECURED BEFORE TAKING OFF, THE PILOT'S IMPROPER IN-FLIGHT PLANNING AND DECISION BY MAKING STEEP TURNS TO MANEUVER AND LAND, AND THE PILOT'S ATTENTION BEING DIVERTED BY NOISE FROM THE OPEN DOOR (AURAL PERCEPTION).