Narrative:

Approximately 5 mins after a normal departure out of ont, climbing through 9000 ft, a noise similar to a rubber mallet striking the lower nose section of the aircraft (just once) was heard by the flight deck crew and the first flight attendant. All system pages and instruments were checked and found to be normal. The possibility of a bird strike was a consideration. On approach into phx, descending out of 6000 ft, after flaps 1 degree selected, the decision to lower the gear earlier than normal was made just in case it was not a bird strike (which we had pretty much ruled out anyway). After the gear was selected down, there was no indication that the mains nor the nose gear had extended. The landing gear system page indicated that the left nose gear door was just barely open. All other gear doors appeared open. ATC was notified, we broke off the approach and completed the ECAM actions (consisted of cycling the gear handle gain with the same result) and performed the gravity gear extension. This resulted in positive indications that the mains and nose gear were down and locked, but the nose gear door was still showing barely open on the left side. Flight attendants and company dispatch were advised of situation. A low fly-by of the tower was made and we were informed that all gear and doors appeared to be down and locked. Due to the gravity gear extension, we would no longer have nosewheel steering and because we were experiencing what we perceived to be a higher than normal vibration even with the gear doors remaining in the down position (they normally retract again after a normal extension), an emergency was declared, emergency equipment requested, and the flight attendants were instructed to prepare for an emergency landing. Company dispatch was notified and a request was made for a tug to tow the aircraft to the gate after landing if all went well. A normal landing was made and the aircraft brought to a stop on runway 8R at phx. After a brief examination by emergency personnel revealed little to no appearance of damage, etc, the gear pins were thrown down to company ground crew personnel for installation prior to towing. Aircraft was towed to gate and subsequent investigation revealed that one end of the hydraulic shock attached to the left nose gear door had broken its shear pin and also broke off 1/2 of the 'ear' attachment bracket. This must have been the noise heard on climb out from ont. None of the broken parts were found to my knowledge and probably fell from the aircraft after the gear was eventually lowered. There is no way that this could have been discovered on a normal preflight walkaround since the gear doors are normally closed, and based on the noise heard well after a normal gear retraction out of ont, the failure did not occur (probably) until then anyway. I believe all procedures and communications with appropriate facilities and flight attendants were performed in accordance with company policies and procedures. (With no hydraulic shock attached to nose door, the door still appeared down but was not rigid resulting in aircraft vibration.)

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Original NASA ASRS Text

Title: A320 ACFT FLC HEARD A THUMP IN THE VICINITY OF THE NOSE GEAR DURING CLBOUT. ON APCH WHEN THE LNDG GEAR WAS EXTENDED THERE WAS NO INDICATION OF THE GEAR EXTENSION. THE LNDG GEAR PAGE ON THE MCDU SHOWED L NOSE GEAR DOOR BARELY OPEN. ECAM PROCS WERE COMPLETED INCLUDING GRAVITY GEAR EXTENSION. TWR FLY-BY SHOWED ALL GEAR AND DOORS OPEN. AFTER A NORMAL LNDG THE ACFT WAS STOPPED ON THE RWY, GEAR PINS INSTALLED AND ACFT TOWED TO THE GATE.

Narrative: APPROX 5 MINS AFTER A NORMAL DEP OUT OF ONT, CLBING THROUGH 9000 FT, A NOISE SIMILAR TO A RUBBER MALLET STRIKING THE LOWER NOSE SECTION OF THE ACFT (JUST ONCE) WAS HEARD BY THE FLT DECK CREW AND THE FIRST FLT ATTENDANT. ALL SYS PAGES AND INSTS WERE CHKED AND FOUND TO BE NORMAL. THE POSSIBILITY OF A BIRD STRIKE WAS A CONSIDERATION. ON APCH INTO PHX, DSNDING OUT OF 6000 FT, AFTER FLAPS 1 DEG SELECTED, THE DECISION TO LOWER THE GEAR EARLIER THAN NORMAL WAS MADE JUST IN CASE IT WAS NOT A BIRD STRIKE (WHICH WE HAD PRETTY MUCH RULED OUT ANYWAY). AFTER THE GEAR WAS SELECTED DOWN, THERE WAS NO INDICATION THAT THE MAINS NOR THE NOSE GEAR HAD EXTENDED. THE LNDG GEAR SYS PAGE INDICATED THAT THE L NOSE GEAR DOOR WAS JUST BARELY OPEN. ALL OTHER GEAR DOORS APPEARED OPEN. ATC WAS NOTIFIED, WE BROKE OFF THE APCH AND COMPLETED THE ECAM ACTIONS (CONSISTED OF CYCLING THE GEAR HANDLE GAIN WITH THE SAME RESULT) AND PERFORMED THE GRAVITY GEAR EXTENSION. THIS RESULTED IN POSITIVE INDICATIONS THAT THE MAINS AND NOSE GEAR WERE DOWN AND LOCKED, BUT THE NOSE GEAR DOOR WAS STILL SHOWING BARELY OPEN ON THE L SIDE. FLT ATTENDANTS AND COMPANY DISPATCH WERE ADVISED OF SIT. A LOW FLY-BY OF THE TWR WAS MADE AND WE WERE INFORMED THAT ALL GEAR AND DOORS APPEARED TO BE DOWN AND LOCKED. DUE TO THE GRAVITY GEAR EXTENSION, WE WOULD NO LONGER HAVE NOSEWHEEL STEERING AND BECAUSE WE WERE EXPERIENCING WHAT WE PERCEIVED TO BE A HIGHER THAN NORMAL VIBRATION EVEN WITH THE GEAR DOORS REMAINING IN THE DOWN POS (THEY NORMALLY RETRACT AGAIN AFTER A NORMAL EXTENSION), AN EMER WAS DECLARED, EMER EQUIP REQUESTED, AND THE FLT ATTENDANTS WERE INSTRUCTED TO PREPARE FOR AN EMER LNDG. COMPANY DISPATCH WAS NOTIFIED AND A REQUEST WAS MADE FOR A TUG TO TOW THE ACFT TO THE GATE AFTER LNDG IF ALL WENT WELL. A NORMAL LNDG WAS MADE AND THE ACFT BROUGHT TO A STOP ON RWY 8R AT PHX. AFTER A BRIEF EXAMINATION BY EMER PERSONNEL REVEALED LITTLE TO NO APPEARANCE OF DAMAGE, ETC, THE GEAR PINS WERE THROWN DOWN TO COMPANY GND CREW PERSONNEL FOR INSTALLATION PRIOR TO TOWING. ACFT WAS TOWED TO GATE AND SUBSEQUENT INVESTIGATION REVEALED THAT ONE END OF THE HYD SHOCK ATTACHED TO THE L NOSE GEAR DOOR HAD BROKEN ITS SHEAR PIN AND ALSO BROKE OFF 1/2 OF THE 'EAR' ATTACHMENT BRACKET. THIS MUST HAVE BEEN THE NOISE HEARD ON CLBOUT FROM ONT. NONE OF THE BROKEN PARTS WERE FOUND TO MY KNOWLEDGE AND PROBABLY FELL FROM THE ACFT AFTER THE GEAR WAS EVENTUALLY LOWERED. THERE IS NO WAY THAT THIS COULD HAVE BEEN DISCOVERED ON A NORMAL PREFLT WALKAROUND SINCE THE GEAR DOORS ARE NORMALLY CLOSED, AND BASED ON THE NOISE HEARD WELL AFTER A NORMAL GEAR RETRACTION OUT OF ONT, THE FAILURE DID NOT OCCUR (PROBABLY) UNTIL THEN ANYWAY. I BELIEVE ALL PROCS AND COMS WITH APPROPRIATE FACILITIES AND FLT ATTENDANTS WERE PERFORMED IN ACCORDANCE WITH COMPANY POLICIES AND PROCS. (WITH NO HYD SHOCK ATTACHED TO NOSE DOOR, THE DOOR STILL APPEARED DOWN BUT WAS NOT RIGID RESULTING IN ACFT VIBRATION.)

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.