[Federal Register Volume 69, Number 198 (Thursday, October 14, 2004)]
[Notices]
[Page 61067]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-23068]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration


Advisory Circular (AC) 23.629-1B, Means of Compliance With Title 
14 CFR, Part 23, Sec.  23.629, Flutter

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of issuance of advisory circular.

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SUMMARY: This notice announces the issuance of Advisory Circular (AC) 
23.629-1B. This advisory circular presents information and guidance to 
provide one means, but not the only means of complying with Sec.  
23.629, Flutter (including divergence, and control reversal) of part 23 
of the Federal Aviation Regulations. Accordingly, this material is 
neither mandatory nor regulatory in nature.
    The complexity of flutter analysis has historically prompted 
endeavors to find simplified methods of flutter substantiation. The 
advent of electronic computers has de-emphasized the need to make 
drastic assumptions previously necessary to enable mathematical 
treatment of the flutter phenomenon. However, there remains a need to 
simplify flutter solution as much as possible consistent with safety in 
order to minimize the cost and effort required to show freedom from 
flutter. Past experiences gained by the necessity to judiciously choose 
degrees of freedom, and by the need to make essential parametric 
studies has resulted in a generally recognized set of good practices. 
These good practices form the basis for this advisory circular.
    The draft advisory circular was issued for Public Comment on 
February 25, 2004 (69 FR 8728). When possible, comments received were 
used to modify the draft advisory circular.
    We received some comments regarding the general layout of the 
advisory circular. We will consider reorganizing the content for the 
next revision. Any suggestions for the reorganization will be 
considered. For more information, or to make recommendations for the 
improvement of this advisory circular, contact Mark James, Standards 
Office, Small Airplane Directorate, Aircraft Certification Service, 
Kansas City, Missouri 64106, telephone (816) 329-4137, fax (816) 329-
4090, [email protected].

DATES: Advisory Circular (AC) 23-629-1B was issued by the Manager, 
Small Airplane Directorate on September 28, 2004.
    How to Obtain Copies: A paper copy of AC 23.629-1B may be obtained 
by writing to the U.S. Department of Transportation, Subsequent 
Distribution Office, DOT Warehouse, SVC-121.23, Ardmore East Business 
Center, 3341Q 75th Avenue, Landover, MD 20785, telephone 301-322-5377, 
or by faxing your request to the warehouse at 301-386-5394. The policy 
will also be available on the Internet at http://www.airweb.faa.gov/AC.

    Issued in Kansas City, Missouri, on September 28, 2004.
Dorenda D. Baker,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 04-23068 Filed 10-13-04; 8:45 am]
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