# Progressive inspection — Aircraft inspection and test intervals under 14 CFR Part 91

For Progressive inspection, interval is within each 12 calendar months; applies to is aircraft; regulation section is § 91.409, verified against its source on 2026-08-06.

- **Inspection or test item:** Progressive inspection _(verified: appears in the quote below)_
- **Interval:** within each 12 calendar months _(verified: appears in the quote below)_
- **Applies to:** aircraft _(verified: appears in the quote below)_
- **Regulation section:** § 91.409 _(verified: appears in the quote below)_

## What the source says

> The frequency and detail of the progressive inspection shall provide for the complete inspection of the aircraft within each 12 calendar months and be consistent with the manufacturer's recommendations, field service experience, and the kind of operation in which the aircraft is engaged.

## Source

- https://www.ecfr.gov/api/versioner/v1/full/2026-08-01/title-14.xml?part=91&section=91.409

Last verified: 2026-08-06. Review by: 2028-08-05.
Part of [Aircraft inspection and test intervals under 14 CFR Part 91](https://referencesource.org/aircraft-inspection-and-test-intervals/).