The U.S. aircraft register, updated daily
Parts

Top Frame

No failure report names the top frame. 3 FAA approvals let 3 companies make a replacement top frame, Snaky Creek Enterprises LLC DBA Spectrum Aeromed holding the most (1).

Approved replacement parts 3 parts manufacturer approvals

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

For these models most: Sikorsky S-76 (1), Bell 407 (1).

MakerPartReplacesFitsGrantedStatus
Balloonacy LTD LLCTop Frame Support RB Gondola ARP5320453204Aerostar Intl, Inc. All series with RB series gondolas installed2013-07-07current
Keystone Helicopter CorporationTop Frame Sub-Assembly 9DS-01-0108Modification PartSikorsky S76A, B, C2004-06-21current
Snaky Creek Enterprises LLC DBA Spectrum AeromedTop Frame TF-407Modification partBell 4071999-10-18current

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.