# Proposed AD FAA-2021-0157: Learjet Inc.

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 2021-23-08
- Products: Learjet
- Product type: Aircraft
- Action: Notice of proposed rulemaking (NPRM).
- Published: July 28, 2021, 86 FR 40379
- Comments due: September 13, 2021
- Became: [AD 2021-23-08](https://openairdocs.org/ad/2021-23-08)
- Docket: FAA-2021-0157 (https://www.regulations.gov/docket/FAA-2021-0157, where comments are filed)
- Project: AD-2020-00483-T
- FR document: 2021-15953
- Official PDF: https://openairdocs.org/files/sha256/a2/a2/a2a2983fa74648df261b1abadfe3131b8c8e2561232ecb9e87266fb999fed0ab (from https://www.govinfo.gov/content/pkg/FR-2021-07-28/pdf/2021-15953.pdf)
- Federal Register: https://www.federalregister.gov/documents/2021/07/28/2021-15953/airworthiness-directives-learjet-inc
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/C0199CBFD58A2EFA8625872100791ED0.0001
- Page: https://openairdocs.org/proposed/FAA-2021-0157

## Summary

The FAA proposes to adopt a new airworthiness directive (AD) for certain Learjet Inc. (Learjet) Model 45 airplanes. This proposed AD was prompted by reports of corrosion found on the upper surface of the lower center wing mid spar splice plate. This proposed AD would require repetitively inspecting the center wing area for corrosion and deterioration of protective treatments, removing any corrosion, and treating any deteriorated areas. The FAA is proposing this AD to address the unsafe condition on these products.

## Notices in this docket

- Jul 28, 2021: Notice of proposed rulemaking (NPRM). (first notice), FR document 2021-15953, comments due Sep 13, 2021 (https://www.federalregister.gov/documents/2021/07/28/2021-15953/airworthiness-directives-learjet-inc)

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.