Narrative:

During nighttime preflight on ramp in lax, crew failed to remove maintenance main gear locks. There were no flags on either lock, and captain and first officer failed to notice them. First officer removed nosewheel lock, but, because of poor lighting did not remove main locks. Aircraft was parked in a dark corner of the ramp. We departed runway 24L at lax, and when gear failed to retract, returned to an uneventful landing in lax. A more vigilant preflight and better lighting conditions with flags on locks would go a long way.

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Original NASA ASRS Text

Title: RETURN LAND MANDATED BY THE GEAR FAILING TO RETRACT ON TKOF. GEAR DOWN LOCK PINS WERE NOT REMOVED.

Narrative: DURING NIGHTTIME PREFLT ON RAMP IN LAX, CREW FAILED TO REMOVE MAINT MAIN GEAR LOCKS. THERE WERE NO FLAGS ON EITHER LOCK, AND CAPT AND FO FAILED TO NOTICE THEM. FO REMOVED NOSEWHEEL LOCK, BUT, BECAUSE OF POOR LIGHTING DID NOT REMOVE MAIN LOCKS. ACFT WAS PARKED IN A DARK CORNER OF THE RAMP. WE DEPARTED RWY 24L AT LAX, AND WHEN GEAR FAILED TO RETRACT, RETURNED TO AN UNEVENTFUL LNDG IN LAX. A MORE VIGILANT PREFLT AND BETTER LIGHTING CONDITIONS WITH FLAGS ON LOCKS WOULD GO A LONG WAY.

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.