# Proposed AD 99-NM-26-AD: Bombardier Model CL-600-1A11 (CL-600) and CL-600-2A12 (CL-601) Series Airplanes

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 2000-19-01
- Action: Notice of proposed rulemaking (NPRM).
- Published: March 31, 2000, 65 FR 17208
- Comments due: May 1, 2000
- Became: [AD 2000-19-01](https://openairdocs.org/ad/2000-19-01)
- Docket: 99-NM-26-AD
- FR document: 00-8019
- Official PDF: https://openairdocs.org/files/sha256/82/d0/82d03e6312d663e60edc493b695f9b1268bee30c184f83a55b524c7a50175ee0 (from https://www.govinfo.gov/content/pkg/FR-2000-03-31/pdf/00-8019.pdf)
- Federal Register: https://www.federalregister.gov/documents/2000/03/31/00-8019/airworthiness-directives-bombardier-model-cl-600-1a11-cl-600-and-cl-600-2a12-cl-601-series-airplanes
- Page: https://openairdocs.org/proposed/99-NM-26-AD

## Summary

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Bombardier Model CL-600- 1A11 (CL-600) and CL-600-2A12 (CL-601) series airplanes. This proposal would require modification of the main landing gear (MLG) brake units and inboard MLG wheels; and a revision to the Airplane Flight Manual (AFM) to include the increased cooling times for the modified brakes. This proposal also would allow, for certain cases, removal of the inboard and/or outboard wheel discs by installation of a placard to limit airplane operation on the ground and a revision to the AFM to include information for operating the airplane with the wheel discs removed. 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 prevent water freezing on the brake while the airplane is in flight due to water, slush, or snow from the runway entering into the brake assemblies during takeoff, and consequently, a tire burst during landing of the airplane.

## Notices in this docket

- Mar 31, 2000: Notice of proposed rulemaking (NPRM). (first notice), FR document 00-8019, comments due May 1, 2000 (https://www.federalregister.gov/documents/2000/03/31/00-8019/airworthiness-directives-bombardier-model-cl-600-1a11-cl-600-and-cl-600-2a12-cl-601-series-airplanes)

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