Narrative:

Shortly after departure; talking to lax center got an 'rnp' flag in both pfd's. During our evaluation of the problem and verifying our position; lax center called and questioned our position and gave us a heading. Informed ATC our FMS wasn't working properly and changed our flight plan designation.

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Original NASA ASRS Text

Title: An MD-80 flight crew reported a malfunctioning FMS to ATC; and they flew VOR-based navigation to destination.

Narrative: Shortly after departure; talking to LAX Center got an 'RNP' flag in both PFD's. During our evaluation of the problem and verifying our position; LAX Center called and questioned our position and gave us a heading. Informed ATC our FMS wasn't working properly and changed our flight plan designation.

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.