As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAD - FL 442 - DURING GEAR RETRACTION, THE NOSE GEAR UNSAFE LIGHT REMAINED ILLUMINATED. CREW CYCLED THE GEAR AND RECEIVED NORMAL SAFE INDICATIONS. UPON GEAR EXTENSION AT ARRIVAL, THE NOSE GEAR UNSAFE LIGHT AGAIN REMAINED ILLUMINATED. CREW BROKE OFF APPROACH AND VISUALLY SIGHTED THE GEAR DOWN AND LOCKED. FLIGHT LANDED WITH NO FURTHER INCIDENT. MAINTENANCE CLEANED THE NOSE GEAR SENSOR AND REPLACED THE PROXIMITY SWITCHING UNIT. (M)