Narrative:

On approach to ZZZ, upon gear extension, we observed the nose gear down indicator was red and displayed 'unlocked.' upon selection of full flaps, a master warning aural alert accompanied with ECAM message for gear not down occurred. At this point a missed approached was executed by first officer. Landing gear was retracted per go around procedure. After stabilized on vector for new approach, we attempted to lower the gear again. The same unlocked condition for nose gear was displayed as well as a nosewheel steering fault. The gear was left down for the remainder of the flight. At this point I contacted dispatch on the radio for a patch to maintenance to assist with troubleshooting the situation. After discussing indications with maintenance it was determined that a possibility existed that the nosewheel might be turned 90 degrees from its normal position. Sounding to us like a potential problem upon landing, we declared an emergency with dispatch and ATC and requested emergency equipment standing by. I then briefed the flight attendants and passenger of the situation, and requested a prep for evacuate/evacuation be conducted as a precaution. After discussing possible scenarios with the first officer, flight deck observer, and purser, I performed a normal ILS to ZZZ. The brace signal was given just prior to touchdown by the flight deck observer. Landing was uneventful with the exception of no nosewheel steering. I cleared the runway using differential braking and thrust without any difficulty. The passenger were instructed to remain seated. I stopped the aircraft on the taxiway and requested a visual inspection of the nosewheel area by fire and rescue. They indicated that all looked normal and were cleared from the scene. We called for maintenance and tug to tow to terminal as nosewheel steering was inoperative. The APU was started and the engines shut down. We arrived at the gate 30 mins after touchdown. From jetbridge phone, I called our dispatcher and had a conference call with him and the flight operations duty manager to describe the events of the flight. Callback conversation with reporter revealed the following information: with the red nose gear position warning light on and the gear extended, the nose gear doors are open and will not close. A normal landing was made and it was then discovered the airplane had no nosewheel steering and a tug was required for movement to the gate. The nosewheel steering was lost due to the nose gear doors being open. The gear warning problem was caused by a failed nose gear downlock sensor. Maintenance replaced the downlock position sensor and the nose gear steering servo control valve.

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Original NASA ASRS Text

Title: AN A320 ON APCH AT 1000 FT DECLARED AN EMER DUE TO NOSE GEAR RED UNSAFE INDICATION. EXTENDED FLAPS. HAD ECAM FOR GEAR NOT DOWN AND MASTER WARNING. GEAR RECYCLED. NO CHANGE.

Narrative: ON APCH TO ZZZ, UPON GEAR EXTENSION, WE OBSERVED THE NOSE GEAR DOWN INDICATOR WAS RED AND DISPLAYED 'UNLOCKED.' UPON SELECTION OF FULL FLAPS, A MASTER WARNING AURAL ALERT ACCOMPANIED WITH ECAM MESSAGE FOR GEAR NOT DOWN OCCURRED. AT THIS POINT A MISSED APCHED WAS EXECUTED BY FO. LNDG GEAR WAS RETRACTED PER GAR PROC. AFTER STABILIZED ON VECTOR FOR NEW APCH, WE ATTEMPTED TO LOWER THE GEAR AGAIN. THE SAME UNLOCKED CONDITION FOR NOSE GEAR WAS DISPLAYED AS WELL AS A NOSEWHEEL STEERING FAULT. THE GEAR WAS LEFT DOWN FOR THE REMAINDER OF THE FLT. AT THIS POINT I CONTACTED DISPATCH ON THE RADIO FOR A PATCH TO MAINT TO ASSIST WITH TROUBLESHOOTING THE SIT. AFTER DISCUSSING INDICATIONS WITH MAINT IT WAS DETERMINED THAT A POSSIBILITY EXISTED THAT THE NOSEWHEEL MIGHT BE TURNED 90 DEGS FROM ITS NORMAL POS. SOUNDING TO US LIKE A POTENTIAL PROB UPON LNDG, WE DECLARED AN EMER WITH DISPATCH AND ATC AND REQUESTED EMER EQUIP STANDING BY. I THEN BRIEFED THE FLT ATTENDANTS AND PAX OF THE SIT, AND REQUESTED A PREP FOR EVAC BE CONDUCTED AS A PRECAUTION. AFTER DISCUSSING POSSIBLE SCENARIOS WITH THE FO, FLT DECK OBSERVER, AND PURSER, I PERFORMED A NORMAL ILS TO ZZZ. THE BRACE SIGNAL WAS GIVEN JUST PRIOR TO TOUCHDOWN BY THE FLT DECK OBSERVER. LNDG WAS UNEVENTFUL WITH THE EXCEPTION OF NO NOSEWHEEL STEERING. I CLRED THE RWY USING DIFFERENTIAL BRAKING AND THRUST WITHOUT ANY DIFFICULTY. THE PAX WERE INSTRUCTED TO REMAIN SEATED. I STOPPED THE ACFT ON THE TXWY AND REQUESTED A VISUAL INSPECTION OF THE NOSEWHEEL AREA BY FIRE AND RESCUE. THEY INDICATED THAT ALL LOOKED NORMAL AND WERE CLRED FROM THE SCENE. WE CALLED FOR MAINT AND TUG TO TOW TO TERMINAL AS NOSEWHEEL STEERING WAS INOP. THE APU WAS STARTED AND THE ENGINES SHUT DOWN. WE ARRIVED AT THE GATE 30 MINS AFTER TOUCHDOWN. FROM JETBRIDGE PHONE, I CALLED OUR DISPATCHER AND HAD A CONFERENCE CALL WITH HIM AND THE FLT OPS DUTY MANAGER TO DESCRIBE THE EVENTS OF THE FLT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: WITH THE RED NOSE GEAR POS WARNING LIGHT ON AND THE GEAR EXTENDED, THE NOSE GEAR DOORS ARE OPEN AND WILL NOT CLOSE. A NORMAL LNDG WAS MADE AND IT WAS THEN DISCOVERED THE AIRPLANE HAD NO NOSEWHEEL STEERING AND A TUG WAS REQUIRED FOR MOVEMENT TO THE GATE. THE NOSEWHEEL STEERING WAS LOST DUE TO THE NOSE GEAR DOORS BEING OPEN. THE GEAR WARNING PROB WAS CAUSED BY A FAILED NOSE GEAR DOWNLOCK SENSOR. MAINT REPLACED THE DOWNLOCK POS SENSOR AND THE NOSE GEAR STEERING SERVO CTL VALVE.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.