Narrative:

On approach to runway 27L at ord got a red warning that landing gear was unsafe. Lower ECAM showed 1 red triangle on nose gear. Executed missed approach. Advised ATC. Recycled landing gear and had everything green until configured flaps 3 degrees for ILS, again got continuous repetitive chime, red master warning. ECAM warning gear unsafe and red triangle on ECAM nose gear. I assumed the problem was being caused by a faulty proximity switch but couldn't be absolutely sure so declared an emergency and briefed the flight attendants for a possible nose gear failure on touchdown. Completed the landing gear down/not locked QRH checklist except did not do the gravity extension procedure as called for since I was pretty sure the nose gear was downlocked. Landed without incident however, nosewheel steering failed during taxi and had to be towed to gate. Maintenance determined proximity switch on nose gear was in fact defective. In retrospect, I should have completed the entire QRH checklist as published including the gravity extension of the landing gear as had the nose gear collapsed on landing I may have been criticized, or worse, for not doing so. Henceforth if I have any problem that has a QRH checklist, I will perform the checklist in its entirety to make sure all bases are covered.

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Original NASA ASRS Text

Title: A320 HAD TO ABANDON AN APCH WHEN A RED GEAR UNSAFE LIGHT ILLUMINATED. FOLLOWED SOP EXCEPT FOR THE GRAVITY EXTENSION OF THE GEAR. LIGHT REMAINED ON. LNDG WAS NORMAL BUT NOSE GEAR STEERING FAILED WHILE TAXIING.

Narrative: ON APCH TO RWY 27L AT ORD GOT A RED WARNING THAT LNDG GEAR WAS UNSAFE. LOWER ECAM SHOWED 1 RED TRIANGLE ON NOSE GEAR. EXECUTED MISSED APCH. ADVISED ATC. RECYCLED LNDG GEAR AND HAD EVERYTHING GREEN UNTIL CONFIGURED FLAPS 3 DEGS FOR ILS, AGAIN GOT CONTINUOUS REPETITIVE CHIME, RED MASTER WARNING. ECAM WARNING GEAR UNSAFE AND RED TRIANGLE ON ECAM NOSE GEAR. I ASSUMED THE PROB WAS BEING CAUSED BY A FAULTY PROX SWITCH BUT COULDN'T BE ABSOLUTELY SURE SO DECLARED AN EMER AND BRIEFED THE FLT ATTENDANTS FOR A POSSIBLE NOSE GEAR FAILURE ON TOUCHDOWN. COMPLETED THE LNDG GEAR DOWN/NOT LOCKED QRH CHKLIST EXCEPT DID NOT DO THE GRAVITY EXTENSION PROC AS CALLED FOR SINCE I WAS PRETTY SURE THE NOSE GEAR WAS DOWNLOCKED. LANDED WITHOUT INCIDENT HOWEVER, NOSEWHEEL STEERING FAILED DURING TAXI AND HAD TO BE TOWED TO GATE. MAINT DETERMINED PROX SWITCH ON NOSE GEAR WAS IN FACT DEFECTIVE. IN RETROSPECT, I SHOULD HAVE COMPLETED THE ENTIRE QRH CHKLIST AS PUBLISHED INCLUDING THE GRAVITY EXTENSION OF THE LNDG GEAR AS HAD THE NOSE GEAR COLLAPSED ON LNDG I MAY HAVE BEEN CRITICIZED, OR WORSE, FOR NOT DOING SO. HENCEFORTH IF I HAVE ANY PROB THAT HAS A QRH CHKLIST, I WILL PERFORM THE CHKLIST IN ITS ENTIRETY TO MAKE SURE ALL BASES ARE COVERED.

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.