# Proposed AD FAA-2009-0386: Construcciones Aeronauticas, S.A. (CASA), Model CN-235, CN-235-100, CN-235-200, and CN-235-300 Airplanes

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 2009-18-06
- Products: Construcciones Aeronauticas
- Product type: Aircraft
- Action: Notice of proposed rulemaking (NPRM).
- Published: April 29, 2009, 74 FR 19460
- Comments due: May 29, 2009
- Became: [AD 2009-18-06](https://openairdocs.org/ad/2009-18-06)
- Docket: FAA-2009-0386 (https://www.regulations.gov/docket/FAA-2009-0386, where comments are filed)
- Project: 2008-NM-184-AD
- FR document: E9-9730
- Official PDF: https://openairdocs.org/files/sha256/89/f6/89f63e12a12b963ed83478d2a768b90c18e68bdd6a77275b0215c97ced04067d (from https://www.govinfo.gov/content/pkg/FR-2009-04-29/pdf/E9-9730.pdf)
- Federal Register: https://www.federalregister.gov/documents/2009/04/29/E9-9730/airworthiness-directives-construcciones-aeronauticas-sa-casa-model-cn-235-cn-235-100-cn-235-200-and
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/77C88D9399CC66EC862575A7004C45CD.0001
- Page: https://openairdocs.org/proposed/FAA-2009-0386

## Summary

We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as: During operation in icing conditions, an asymmetric configuration of the de-icing boots was detected, occurring during the inflation and deflation check of the de-icing system. This was found to be due to an unexpected failure mode in the pneumatic and de-icing system's control electronic logic. This condition, if not corrected, could affect the de-icing capabilities of the boots installed on the wing and horizontal stabilizers, potentially leading to loss of control of the aircraft. The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI.

## Notices in this docket

- Apr 29, 2009: Notice of proposed rulemaking (NPRM). (first notice), FR document E9-9730, comments due May 29, 2009 (https://www.federalregister.gov/documents/2009/04/29/E9-9730/airworthiness-directives-construcciones-aeronauticas-sa-casa-model-cn-235-cn-235-100-cn-235-200-and)

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