Narrative:

While on final approach I called for gear down; flaps 15. The nose and right main gear came down and locked okay; but the left main did not extend. We declared an emergency; consulted the QRH and cycled the gear twice with no change in results. Later; level at about 1;000 [feet] AGL for a fly by the tower; we lowered the gear once again but this time we got three green lights. The tower took a look and said all looked good. We were then sequenced around for a landing during which we left the gear down and landed uneventfully. We stopped on the centerline while crash fire rescue equipment took a look at the gear. They all looked good so we taxied to the gate followed by the fire truck.

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Original NASA ASRS Text

Title: A B737-800 flight crew abandoned their approach when the left main gear failed to extend. During a subsequent fly-by of the Tower the gear extended normally and an uneventful landing ensued.

Narrative: While on final approach I called for gear down; Flaps 15. The nose and right main gear came down and locked okay; but the left main did not extend. We declared an emergency; consulted the QRH and cycled the gear twice with no change in results. Later; level at about 1;000 [feet] AGL for a fly by the Tower; we lowered the gear once again but this time we got three green lights. The Tower took a look and said all looked good. We were then sequenced around for a landing during which we left the gear down and landed uneventfully. We stopped on the centerline while CFR took a look at the gear. They all looked good so we taxied to the gate followed by the fire truck.

Data retrieved from NASA's ASRS site as of July 2013 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.