Narrative:

Altitude deviation during system failure. During arrival into ewr at 6000 ft level flight, aircraft experienced major navigation failure with loss of FMS, autoplt, autothrottle, flight director and all aural warnings. While recovering the system, the aircraft descended to 5600 ft. As we returned to 6000 ft, approach control queried us on our altitude. After explaining our situation, approach commented that there was no problem. No apparent loss of separation occurred.

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Original NASA ASRS Text

Title: MD80 CREW HAD MULTIPLE INST AND SYS FAILURE.

Narrative: ALTDEV DURING SYS FAILURE. DURING ARR INTO EWR AT 6000 FT LEVEL FLT, ACFT EXPERIENCED MAJOR NAV FAILURE WITH LOSS OF FMS, AUTOPLT, AUTOTHROTTLE, FLT DIRECTOR AND ALL AURAL WARNINGS. WHILE RECOVERING THE SYS, THE ACFT DSNDED TO 5600 FT. AS WE RETURNED TO 6000 FT, APCH CTL QUERIED US ON OUR ALT. AFTER EXPLAINING OUR SIT, APCH COMMENTED THAT THERE WAS NO PROB. NO APPARENT LOSS OF SEPARATION OCCURRED.

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.