# Proposed AD FAA-2009-0263: Dassault Model Mystere-Falcon 20-C5, 20-D5, 20-E5, and 20-F5 Airplanes

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 2009-14-07
- Products: Dassault
- Product type: Aircraft
- Action: Notice of proposed rulemaking (NPRM).
- Published: March 26, 2009, 74 FR 13147
- Comments due: April 27, 2009
- Became: [AD 2009-14-07](https://openairdocs.org/ad/2009-14-07)
- Docket: FAA-2009-0263 (https://www.regulations.gov/docket/FAA-2009-0263, where comments are filed)
- Project: 2008-NM-137-AD
- FR document: E9-6735
- Official PDF: https://openairdocs.org/files/sha256/71/72/717223234db3b0f3c8152a7954e2fccabb247f53dbbf678ef5ce28aff0d45724 (from https://www.govinfo.gov/content/pkg/FR-2009-03-26/pdf/E9-6735.pdf)
- Federal Register: https://www.federalregister.gov/documents/2009/03/26/E9-6735/airworthiness-directives-dassault-model-mystere-falcon-20-c5-20-d5-20-e5-and-20-f5-airplanes
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/7DF5B790D5DECD3C86257585005B0E89.0001
- Page: https://openairdocs.org/proposed/FAA-2009-0263

## 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:

This Airworthiness Directive (AD) is issued following the discovery of hot air leaks when operating the wing anti-icing system. The seals Part Number (P/N) MS29513-325, near the de-icing valves (12H1) and (12H2) in frame 33 area, do not have the proper temperature rating. The consequences, in the area of the hot air leak, are risks of ignition of potential hydraulic leaks. * * * * *

The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI.

## Notices in this docket

- Mar 26, 2009: Notice of proposed rulemaking (NPRM). (first notice), FR document E9-6735, comments due Apr 27, 2009 (https://www.federalregister.gov/documents/2009/03/26/E9-6735/airworthiness-directives-dassault-model-mystere-falcon-20-c5-20-d5-20-e5-and-20-f5-airplanes)

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