# Proposed AD 99-NM-165-AD: Bombardier Model DHC-7 Series Airplanes

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 99-26-11
- Action: Notice of proposed rulemaking (NPRM).
- Published: October 14, 1999, 64 FR 55640
- Comments due: November 15, 1999
- Became: [AD 99-26-11](https://openairdocs.org/ad/99-26-11)
- Docket: 99-NM-165-AD
- FR document: 99-26870
- Official PDF: https://openairdocs.org/files/sha256/f3/d0/f3d0bedbefb96b9eabf1b75dda7ea34acc3093c4b5c19d572b972542acb5fd21 (from https://www.govinfo.gov/content/pkg/FR-1999-10-14/pdf/99-26870.pdf)
- Federal Register: https://www.federalregister.gov/documents/1999/10/14/99-26870/airworthiness-directives-bombardier-model-dhc-7-series-airplanes
- Page: https://openairdocs.org/proposed/99-NM-165-AD

## Summary

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Bombardier Model DHC-7 series airplanes. This proposal would require a one-time visual inspection to detect corrosion on the upper half of the lower longerons on the inboard nacelles; and corrective actions, if necessary. This proposal also would require modification of the upper and lower longeron halves. This proposal is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by the proposed AD are intended to detect and correct corrosion in the upper halves of the left and right hand lower longerons on the inboard nacelles, which could result in a landing gear failure.

## Notices in this docket

- Oct 14, 1999: Notice of proposed rulemaking (NPRM). (first notice), FR document 99-26870, comments due Nov 15, 1999 (https://www.federalregister.gov/documents/1999/10/14/99-26870/airworthiness-directives-bombardier-model-dhc-7-series-airplanes)

---
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.