As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING FLIGHT 3436, GEAR WOULD NOT RETRACT EVEN USING GEAR OVERRIDE. USED RETRACT POSITION SPOILER LIGHT ALSO ILLUMINATED. MAINTENANCE REMOVED AND REPLACED PROX SENSOR GA11, ON SYSTEM 2 RIGHT LEG OLEO REF AVRO AMM, ALL SYSTEMS NOW CHECK GOOD AT THIS TIME.