The F.A.Rs shown below pertain to the bi-annual inspection requirements for aircraft static systems, altimeters, altitude reporting equipment and transponders.

91.215 - ATC transponder and altitude reporting equipment and use.

91.217 - Data correspondence between automatically reported
pressure altitude data and the pilot's altitude reference.

91.411 - Altimeter system and altitude reporting equipment tests and inspections.

91.413 - ATC transponder tests and inspections.

Part 43 Appendix E - Altimeter System Test and Inspection.

Part 43 Appendix F - ATC Transponder Tests and Inspection.

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