Digital Calibration
No failure report names the digital calibration. 4 FAA approvals let 1 company make a replacement digital calibration, Smiths Industries/Aerospace 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 digital calibration and sell it as an approved part for the models named. These are the companies holding such approvals for a digital calibration:
For these models most: Boeing 747 (3), Boeing 737 (1).
| Maker | Part | Replaces | Fits | Granted | Status |
|---|---|---|---|---|---|
| Smiths Industries/Aerospace | Digital Calibration Trim Unit 4215-02 | Modification Part | Boeing 737-300, 737-400, 737-500 | 2001-08-14 | current |
| Smiths Industries/Aerospace | Digital Calibration Trim Unit 4215-02 | Boeing 60B92017-8 | Boeing 747-200, -300 | 1993-02-18 | current |
| Smiths Industries/Aerospace | Digital Calibration Trim Unit 4215-05 | Boeing 60B92017-7 | Boeing 747-200, -300 | 1993-02-18 | current |
| Smiths Industries/Aerospace | Digital Calibration Trim Unit 4215-04 | Boeing 60B92017-6 | Boeing 747-200, -300 | 1993-02-18 | 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.