A method and apparatus for identifying the start of a data field using a fault tolerant sync word with 16/17 rate coding is enclosed. The invention provides a word sync field that uses a 16/17 byte pattern that is repeated. The format of the word sync allows the proper identification of the start of the data even if only certain portions of the word sync are recovered. An encoded data block includes a sync field for providing proper timing for bit synchronization and a word sync field following the sync field, the word sync field being written with a predetermined phase relative to the sync field to identify a start of a data field. The word sync field comprises N word sync patterns, each word sync pattern comprising two subpatterns, wherein the phase relationship of the word sync field and the sync field enables identification of the start of the data field by identifying any N subpatterns. Each of the N word sync patterns comprises a 17 bit word sync pattern, the 17 bit word sync patterns comprising an 8 of 9 byte and an 8 of 8 byte. The N word sync patterns further comprises three, two or one word sync patterns forming six, four, or two subpatterns respectively, wherein only half of the subpatterns must be detected to identify the start of the data field.