NPRM FAA-2009-0995

Became AD 2010-13-05

Proposed airworthiness directive · Bombardier

Published
October 28, 2009 · 74 FR 55493
Comments due
December 14, 2009
Action
Notice of proposed rulemaking (NPRM)
Docket
FAA-2009-0995
Project
2009-NM-123-AD
FR document
E9-25866
Products
Aircraft

A proposal is not in force. If adopted, it becomes an AD, usually with changes. Only the Federal Register edition is official.

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:

Investigation into a landing gear retraction problem on a production test flight revealed that, during aircraft pressurization and depressurization cycles, the pressure floor in the main landing gear bay deflects to a small extent. This causes relative misalignment between the [alternate-extension system] AES bypass valve, the downlock assist valve and the summing lever which, in turn, can result in damage to and potential failure of the respective clevis attached to one or both of the valves. Such a clevis failure could remain dormant and, in the subsequent event that use of the AES was required, full landing gear extension may not be achievable.

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

The resulting AD

Notices in this docket · 1