[Federal Register Volume 65, Number 95 (Tuesday, May 16, 2000)]
[Notices]
[Pages 31205-31206]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-12311]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration


Proposed Advisory Circular 25-XX, Sustained Engine Imbalance

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of availability of proposed advisory circular (AC) 25-XX 
and request for comments.

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SUMMARY: This notice announces the availability of and requests 
comments on a proposed advisory circular (AC) which provides methods 
acceptable to

[[Page 31206]]

the Administrator related to the aircraft design for sustained engine 
rotor imbalance conditions provisions of 14 CFR part 25 regarding the 
type certification requirements for transport airplane structure. This 
notice is necessary to give all interested persons an opportunity to 
present their views on the proposed AC.

DATES: Comments must be received on or before July 10, 2000.

ADDRESSES: Send all comments on the proposed AC to: Federal Aviation 
Administration, Attention: Jim Haynes, Airframe/Airworthiness Branch, 
ANM-115, Transport Airplane Directorate, Aircraft Certification 
Service, 1601 Lind Avenue SW, Renton, WA 98055-4056. Comments may also 
be submitted electronically to the following address: 
[email protected]. Comments may be inspected at the above address 
between 7;30 a.m. and 4:00 p.m. weekdays, except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Jim Haynes, Airframe/Airworthiness 
Branch, ANM-115, Transport Airplane Directorate, Aircraft Certification 
Service, 1601 Lind Avenue SW, Renton, WA 98055-4056; telephone (425) 
227-2131; facsimile (425) 227-1320. Questions may also be submitted 
electronically to the following address: [email protected].

SUPPLEMENTARY INFORMATION:  

Comments Invited

    You may obtain an electronic copy of the advisory circular 
identified in this notice at the following Internet address: 
www.faa.gov/avr/air/airhome.htm. If you do not have access to the 
Internet, you may request a copy by contacting Susan Boylon, Program 
Management Branch, ANM-114, FAA Transport Airplane Directorate, 
Aircraft Certification Service, 1601 Lind Avenue SW., Renton, WA 98055-
4056; telephone (425) 227-1152. Interested persons are invited to 
comment on the proposed AC by submitting such written data, views, or 
arguments, as they may desire. Commenters should identify AC 25-XX, and 
submit comments, in duplicate, to the address specified above. All 
communications received on or before the closing date for comments will 
be considered by the Transport Standards Staff before issuing the final 
AC.

Discussion

    This AC contains guidance for the latest amendment of the 
regulations and applies to all transport category airplanes for which a 
new, amended, or supplemental type certificate is required. This 
guidance should be applied to any portion of the airplane structure 
that has been modified. In the past, advisory and guidance information 
applicable to transport airplane structure has been published as AC's. 
Advisory circulars have not been developed for all of the regulatory 
requirements applicable to transport airplane structure, however. In 
many instances, certification of new technology airplanes resulted in 
the need to interpret the existing regulations and to apply new 
regulations. Issue papers and special conditions were generated to 
document the compliance method agreed upon between the applicant and 
the FAA. In other instances, applicants, FAA Aircraft Certification 
Office (ACO) managers, and foreign regulatory authorities have 
requested interpretation of the intent of specific regulations. This 
guidance was documented in the form of policy memorandums that were 
distributed to all ACO's, letters to applicants and foreign 
airworthiness authorities, and issue papers. In many instances, this 
information was not organized in a manner that allowed easy access, and 
applicants were not aware of revised policy. This AC formalizes 
existing policy so that the public and FAA personnel have access to 
this information. The methods and procedures described in this AC have 
evolved after many years and represent current certification practice.

    Issued in Renton, Washington, on May 8, 2000.
Vi L. Lipski,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service, ANM-100.
[FR Doc. 00-12311 Filed 5-15-00; 8:45 am]
BILLING CODE 4910-13-M