Narrative:

Upon arrival at the gate; a passenger told us that a panel on the #2 engine cowling had come off during landing. I inspected and the nacelle access panel on top of the #2 engine pylon was missing. We immediately notified ground control and I contacted maintenance. Local maintenance came out. The panel was found on the runway and returned. The mechanic said there was no other damage and reinstalled panel. On subsequent landing in ZZZ; another passenger notified us that the panel appeared loose and we notified ZZZ maintenance.

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Original NASA ASRS Text

Title: A PAX RPTED TO A B737-500 CREW THAT AN ENG COWLING PANEL SEPARATED ON THE RWY AT TOUCHDOWN.

Narrative: UPON ARR AT THE GATE; A PAX TOLD US THAT A PANEL ON THE #2 ENG COWLING HAD COME OFF DURING LNDG. I INSPECTED AND THE NACELLE ACCESS PANEL ON TOP OF THE #2 ENG PYLON WAS MISSING. WE IMMEDIATELY NOTIFIED GND CTL AND I CONTACTED MAINT. LCL MAINT CAME OUT. THE PANEL WAS FOUND ON THE RWY AND RETURNED. THE MECH SAID THERE WAS NO OTHER DAMAGE AND REINSTALLED PANEL. ON SUBSEQUENT LNDG IN ZZZ; ANOTHER PAX NOTIFIED US THAT THE PANEL APPEARED LOOSE AND WE NOTIFIED ZZZ MAINT.

Data retrieved from NASA's ASRS site as of January 2009 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.