Relay Switching
No failure report names the relay switching. 4 FAA approvals let 1 company make a replacement relay switching, Avionics Support Group, INC. holding the most (4).
Approved replacement parts 4 parts manufacturer approvals
A parts manufacturer approval (PMA) lets a company other than the aircraft's maker make a relay switching and sell it as an approved part for the models named. These are the companies holding such approvals for a relay switching:
For these models most: Boeing 737 (2), Airbus A321 (1), Airbus A320 (1), Airbus A319 (1).
| Maker | Part | Replaces | Fits | Granted | Status |
|---|---|---|---|---|---|
| Avionics Support Group, INC. | Relay Switching Unit 21418499-1 | Modification Part | The Boeing Company B737-300/-400/-500/-600/-700/-800/-90... | 2024-10-28 | current |
| Avionics Support Group, INC. | Relay Switching Unit 21418499-1 | Modification Part | Airbus SAS A319-111/112/113/114/115/131/132/133/... | 2021-12-21 | current |
| Avionics Support Group, INC. | Relay Switching Unit 21418499-1 | Modification Part | Boeing 737-300 Series, 737-400 Series,... | 2017-12-10 | current |
| Avionics Support Group, INC. | Relay Switching Unit 21418499-1 | Modification Part | Boeing 737-300/-400/-500/-600/-700/-800/-900 Series | 2015-10-15 | current |
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.