As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MRI - AIRSTAIR DOOR OPENED AT ROTATION. RETURNED TO MRI AND MADE UNEVENTFUL LANDING. INSPECTED AIRSTAIR DOOR RIGGING AND STRUCTURE, NO DEFECTS NOTED. TESTED DOOR WARNING SYSTEM FOR PROPER OPERATION IAW MM 52-71-00. ADJUSTED AIRSTAIR DOOR HANDLE SWITCH SLIGHTLY TO PRECLUDE FALSE LOCKED SIGNAL. FOUND SWITCH ACTIVATION WAS OCCURRING 0.030 BEFORE PRESSURE LOCK FULLY ENGAGED.