As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PIT - FLT 391 - ON APPROACH, CREW DID NOT RECEIVE A GREEN SAFE INDICATION ON THE RIGHT MAIN LANDING GEAR. NO OTHER ABNORMAL INDICATIONS WERE PRESENT. CREW PERFORMED A GO-AROUND. TOWER CONFIRMED ALL GEAR WERE DOWN. FLIGHT LANDED WITHOUT FURTHR INCIDENT. MAINTENANCE REPLACED THE LIGHT BULB. (M)