The U.S. aircraft register, updated daily
Parts

Rib Root

No failure report names the rib root. 1 FAA approvals let 1 company make a replacement rib root, Big Sky Stearman holding the most (1).

Approved replacement parts 1 parts manufacturer approvals

A parts manufacturer approval (PMA) lets a company other than the aircraft's maker make a rib root and sell it as an approved part for the models named. These are the companies holding such approvals for a rib root:

For these models most: Boeing IB75 (1), Boeing E75 Stearman Kaydet (1), Boeing D75 (1), Boeing B75 Stearman Kaydet (1), Boeing A75 Stearman Kaydet (1), Boeing 75 (1).

MakerPartReplacesFitsGrantedStatus
Big Sky StearmanRib- Root Upper Wing BS75-110675-1106Boeing A75L3*, 75*, A75*2015-05-12current

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.