Responsibility for airworthiness

This regulation establishes that Part 135 certificate holders (commercial operators like charter companies and air taxis) are ultimately responsible for keeping their aircraft airworthy. The operator must ensure all components—airframes, engines, propellers, and parts—are properly maintained according to the regulations and that any defects are fixed between scheduled maintenance.

If the operator maintains its own aircraft under its manual and maintenance program, it has two options: perform all maintenance work itself, or contract it out to another person or facility. When contracting maintenance out, the certificate holder remains responsible for ensuring the work meets the standards in its approved maintenance manual and follows FAA regulations.

In practical terms, this means the operator can't simply hand off an aircraft and wash its hands of maintenance responsibility—it must oversee and verify that all work is done correctly, regardless of who turns the wrenches.

*This is a plain-English summary for study only. The official 14 CFR text on this page is controlling — always read the current regulation and consult a CFI.*