Narrative:

During a part 121 scheduled air carrier flight from hnl to lny on a DHC8, on final at lanai, the gear was selected down and the nose gear indicated unsafe. 'Alternate gear extension using the hand pump' abnormal checklist, which is applicable to all landing gear and landing gear indications malfunctions, was accomplished with no success. An emergency was declared and we returned to hnl. A visual inspection, initiated by ATC, was accomplished by a company aircraft and he indicated that the gear was down and locked. A fly-by of the maintenance hangar was accomplished, and they indicated that gear was down and locked. In my opinion, the gear was not down and locked at this time. At the suggestion of maintenance, we closed the landing gear alternate release and extension doors and returned the landing gear inhibit switch to the norm. These actions contradicted the checklist. These actions repressurized the landing gear extension hydraulic system and resulted in a down and locked indication from both gear position indication system. A successful landing followed and the gear was pinned. Subsequent inspections by maintenance revealed no defects and the failure could not be duplicated. Both the normal extension and the alternate extension system worked normally. Supplemental information from acn 452867: while en route to hnl, we were informed by ATC that a company aircraft, N123, had declared an emergency for a nosewheel not down and locked! Company operations asked ATC to ask us if we would join the other aircraft and visually inspect the position of the gear. We were vectored by ATC to join at an altitude of 3500 ft. We closed to approximately 1/2 mi and informed them that the nose gear appeared to be fully extended. We were then vectored to runway 8L at hnl and landed without incident. Both aircraft had passenger on board. No injuries were reported and no damage occurred.

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Original NASA ASRS Text

Title: A DHC8 CAPT, ON FINAL APCH TO LANAI, EXPERIENCED A LNDG GEAR FAILURE. A COMPANY ACFT MADE A VISUAL FLY-BY TO ASCERTAIN THAT THE GEAR DID APPEAR TO BE DOWN.

Narrative: DURING A PART 121 SCHEDULED ACR FLT FROM HNL TO LNY ON A DHC8, ON FINAL AT LANAI, THE GEAR WAS SELECTED DOWN AND THE NOSE GEAR INDICATED UNSAFE. 'ALTERNATE GEAR EXTENSION USING THE HAND PUMP' ABNORMAL CHKLIST, WHICH IS APPLICABLE TO ALL LNDG GEAR AND LNDG GEAR INDICATIONS MALFUNCTIONS, WAS ACCOMPLISHED WITH NO SUCCESS. AN EMER WAS DECLARED AND WE RETURNED TO HNL. A VISUAL INSPECTION, INITIATED BY ATC, WAS ACCOMPLISHED BY A COMPANY ACFT AND HE INDICATED THAT THE GEAR WAS DOWN AND LOCKED. A FLY-BY OF THE MAINT HANGAR WAS ACCOMPLISHED, AND THEY INDICATED THAT GEAR WAS DOWN AND LOCKED. IN MY OPINION, THE GEAR WAS NOT DOWN AND LOCKED AT THIS TIME. AT THE SUGGESTION OF MAINT, WE CLOSED THE LNDG GEAR ALTERNATE RELEASE AND EXTENSION DOORS AND RETURNED THE LNDG GEAR INHIBIT SWITCH TO THE NORM. THESE ACTIONS CONTRADICTED THE CHKLIST. THESE ACTIONS REPRESSURIZED THE LNDG GEAR EXTENSION HYD SYS AND RESULTED IN A DOWN AND LOCKED INDICATION FROM BOTH GEAR POS INDICATION SYS. A SUCCESSFUL LNDG FOLLOWED AND THE GEAR WAS PINNED. SUBSEQUENT INSPECTIONS BY MAINT REVEALED NO DEFECTS AND THE FAILURE COULD NOT BE DUPLICATED. BOTH THE NORMAL EXTENSION AND THE ALTERNATE EXTENSION SYS WORKED NORMALLY. SUPPLEMENTAL INFO FROM ACN 452867: WHILE ENRTE TO HNL, WE WERE INFORMED BY ATC THAT A COMPANY ACFT, N123, HAD DECLARED AN EMER FOR A NOSEWHEEL NOT DOWN AND LOCKED! COMPANY OPS ASKED ATC TO ASK US IF WE WOULD JOIN THE OTHER ACFT AND VISUALLY INSPECT THE POS OF THE GEAR. WE WERE VECTORED BY ATC TO JOIN AT AN ALT OF 3500 FT. WE CLOSED TO APPROX 1/2 MI AND INFORMED THEM THAT THE NOSE GEAR APPEARED TO BE FULLY EXTENDED. WE WERE THEN VECTORED TO RWY 8L AT HNL AND LANDED WITHOUT INCIDENT. BOTH ACFT HAD PAX ON BOARD. NO INJURIES WERE RPTED AND NO DAMAGE OCCURRED.

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.