Narrative:

The pilot not flying lowered the gear and the result was only a safe down and locked indication for the nose gear and the right main. The left main had no green light and the red light was still illuminated. We informed the tower of the unsafe gear indication and requested to go around. Just a little over #7000lbs fuel remained as we went around. For the next 30 minutes we ran appropriate checklists for unsafe gear indication; manual gear extension; cabin floor main gear view port inspection (during which the right main angled mirror was clear showing down and locked; but the left main mirror was covered in condensation/water); gear jammed up checklist; consulted with dispatch and maintenance control. We then declared an emergency with dispatch agreement who informed the tower. We than returned in sequence for an uneventful flaps 40 landing.

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Original NASA ASRS Text

Title: An unsafe gear indication on approach caused the flight crew of a B737-300 to go around and complete appropriate checklists Subsequently followed by a safe landing.

Narrative: The pilot not flying lowered the gear and the result was only a safe down and locked indication for the nose gear and the right main. The left main had no green light and the red light was still illuminated. We informed the Tower of the unsafe gear indication and requested to go around. Just a little over #7000lbs fuel remained as we went around. For the next 30 minutes we ran appropriate checklists for unsafe gear indication; manual gear extension; cabin floor main gear view port inspection (during which the right main angled mirror was clear showing down and locked; but the left main mirror was covered in condensation/water); gear jammed up checklist; consulted with Dispatch and Maintenance Control. We then declared an emergency with Dispatch agreement who informed the Tower. We than returned in sequence for an uneventful Flaps 40 landing.

Data retrieved from NASA's ASRS site as of April 2012 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.