# Airworthiness Directives; Leonardo S.p.a. (Type Certificate Previously Held by Agusta S.p.A.) Helicopters
> **Rule** · Final rule. · Published 2021-07-20 · Effective 2021-08-24 · 86 FR 38218
## Document
- **Document number:** 2021-15303
- **Category:** airworthiness
- **Manufacturer:** Leonardo S.p.a. (Type Certificate Previously Held by Agusta S.p.A.)
- **Type:** Rule
- **Action:** Final rule.
- **Citation:** 86 FR 38218
- **Publication date:** 2021-07-20
- **Effective date:** 2021-08-24
- **FAA docket:** Docket No. FAA-2021-0348
## Abstract

The FAA is superseding Airworthiness Directive (AD) 2011-18-52 for certain Agusta S.p.A. (now Leonardo S.p.a.) Model AB139 and AW139 helicopters. AD 2011-18-52 required revising the life limit for certain part-numbered tail rotor (T/R) blades, updating the helicopter's historical records, repetitively inspecting each T/R blade for a crack or damage, and depending on the results, replacing the T/R blade. This AD was prompted by the manufacturer developing improved T/R blades using different materials and establishing life limits for each improved blade. This AD retains certain requirements from AD 2011-18- 52, revises certain requirements from AD 2011-18-52, and expands the applicability to include the newly-designed T/R blades. The FAA is issuing this AD to address the unsafe condition on these products.

## Source
- [Federal Register document](https://www.federalregister.gov/documents/2021/07/20/2021-15303/airworthiness-directives-leonardo-spa-type-certificate-previously-held-by-agusta-spa-helicopters)
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