As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
GEAR DISAGREE WITHIN 8 SECONDS AFTER GEAR UP AFTER TAKEOFF. QRH HAD US PUT GEAR BACK DOWN, NO FURTHER ISSUES. REFERENCE AML 1763968 TROUBLESHOT GEAR DISAGREE MSG REF FIM 32-61-05-810-824 FOUND GEAR DISAGREE DUE TO CENTRED SENSOR READING FAR. FOUND NR 1 SENSOR TARGET OUT OF RIG WITH SHIMS INSTALLED INCORRECTLY. PERFORMED GEAR SWING 4X, GEAR DISAGREE DID NOT POPULATE.