The U.S. aircraft register, updated daily
Parts

Castellation

0 failure reports named the castellation in the last ten years, 134 since 1995.

Reports by year

0173451682199568641999
Reports by year, as a table
reports
19952
199868
199964

Sources: the FAA's service difficulty reports since 1995 (a report is a part that failed and was fixed, as filed by an airline, repair station or owner; the count shows reporting as much as reliability) and the parts manufacturer approvals in the FAA's Dynamic Regulatory System. The part name is the reporters' and the approval holders' own words, reduced to the first plain words so that spellings meet.