This read-only Counter64 counts the number of consecutive 9-byte errors the ARQ engine has corrected since the radio link last reached the linkOperational state, the longest burst length tracked in this per-byte-length counter family. A high or fast-growing value here represents the most severe end of correctable error activity the ARQ engine handles on this link. For example, an admin seeing cwrArq9ByteErrs rising alongside falling cwrPctErrorFreeSeconds would treat that as strong evidence the link's RF path has seriously degraded and needs field investigation.