AN FMS AND RELATED AUTOFLT FAILURE DISTRACTED A FLC FROM MEETING A XING RESTR.

Narrative

ON DSCNT INTO EWR ARPT; ON THE WILLIAMSPORT 1 ARR; NAVING ON FMS-RNAV RTE; THE FMS OVERLOADED AND DUMPED THE RTE OFF THE CTL DISPLAY UNIT. THE COPLT WAS FLYING AT THE TIME AND CAPT WAS OPERATING THE RADIOS. THE AUTOPLT DISCONNECTED WITH LOSS OF RTE. THE COPLT FLEW THE ACFT MANUALLY AND THE CAPT RELOADED THE DATA INTO THE FMS TO ACTIVATE THE RTE AGAIN. THE CLRNC WAS TO CROSS SWEET INTXN AT 7000 FT. IN THE CONFUSION THE COPLT CROSSED THE INTXN AT ABOUT 7500 FT. THERE WAS NO CONFLICT WITH TFC AT THE TIME. CTR TURNED THE ACFT TO A HDG OF 080 DEGS FOR VECTORS FOR APCH TO RWY C22L AT NEWARK. SUPPLEMENTAL INFO FROM ACN 301830: BOTH FMC'S DUMPED ALL DATA; AND THE AUTOTHROTTLES AND AUTOPLT DISCONNECTED AT APPROX 10000 FT MSL. I HAND FLEW THE ACFT WHILE THE CAPT CONTINUED TO MAN RADIOS; PERFORM CHKLISTS; AND RELOAD THE COMPUTERS. UPON ATTEMPTING TO REENGAGE THE AUTOFLT SYS; THE AUTOTHROTTLES AND AUTOPLT DID NOT RESPOND PROPERLY; SO WE ELECTED TO DISCONTINUE USE OF ALL AUTOFLT FUNCTIONS. WE ALSO BEGAN TO ENCOUNTER INTERMITTENT LIGHT TO OCCASIONAL MODERATE TURB.