As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT DOOR CAME OFF IN-FLIGHT. AN UNEVENTFUL LANDING WAS MADE TO AN OFFSHORE PLATFORM. MAINTENANCE FOUND HOLE IN THE BRACKET THAT THE TENSION SPRING HOOKS TO HAD PULLED THROUGH, ALLOWING AIRCRAFT NATURAL FREQUENCIES TO WORK EMERGENCY EXIT PINS OUT OF THE DOOR HINGES, THUS RELEASING THE DOOR IN FLIGHT. REPLACED WITH SERVICEABLE BRACKET.