[Federal Register Volume 65, Number 7 (Tuesday, January 11, 2000)]
[Notices]
[Pages 1652-1653]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-580]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration


Proposed Advisory Circular 25-XX, Transport Airplane Propulsion 
Engine and Auxiliary Power Unit Installation Certification Handbook--
The Propulsion Mega AC

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Withdrawal of notice of availability of proposed advisory 
circular.

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SUMMARY: This action withdraws a previously-issued notice of 
availability of proposed Advisory Circular (AC) 25-XX, ``Transport 
Airplane Propulsion Engine and Auxiliary Power Unit Installation 
Certification Handbook--The Propulsion Mega AC.'' The FAA previously 
announced the availability of and requested public comments on that 
proposed AC. The intent of the AC was to provide one consolidated 
source of guidance on methods acceptable to the Administrator for 
showing compliance with the type certification requirements for 
propulsion systems and auxiliary power unit (APU) installations as they 
apply to transport category airplanes. The FAA is withdrawing the 
proposal at this time to allow the majority of the affected public time 
to concentrate their resources towards concluding the harmonization of 
international aviation standards, which the FAA considers a higher 
priority. The FAA intends to re-issue the notice at a later time.

ADDRESSES: Send comments to Steve Happenny, Propulsion/Mechanical 
Systems Branch, ANM-112, Transport Airplane Directorate, Federal 
Aviation Administration, 1601 Lind Avenue SW., Renton, Washington 
98055-4056.

FOR FURTHER INFORMATION CONTACT: Jill DeMarco, Program Management 
Branch, ANM-114, Transport Airplane Directorate, Federal Aviation 
Administration, 1601 Lind Avenue SW., Renton, Washington 98055-4056; 
telephone (425) 227-1313; fax (425) 227-1320.

SUPPLEMENTARY INFORMATION:

Discussion of Original Proposal

    On September 23, 1999, the FAA issued a notice of availability and 
request for comments on proposed Advisory Circular (AC) 25-XX, 
``Transport Airplane Propulsion Engine and Auxiliary Power Unit 
Installation Certification Handbook--The Propulsion Mega AC.'' The 
notice was published in the Federal Register on September 30, 1999 (64 
FR 52819). The FAA initiated the proposed AC in response to requests by 
the affected aviation industry that the FAA provide one comprehensive 
source of FAA policy and guidance on various methods acceptable to the 
FAA Administrator for showing compliance with the type certification 
requirements for propulsion systems and auxiliary power unit (APU) 
installations on transport category airplanes. The public was provided 
until December 29, 1999, to submit comments on the proposed document.

Requests from the Affected Public

    Since issuance of the notice, the FAA has received numerous 
requests from representatives of the affected industry and non-U.S. 
civil aviation authorities, asking that the FAA withhold further action 
on the proposed Propulsion Mega AC.
    These representatives have stated that many in industry who will be 
most affected by the AC are members of Working Groups under the aegis 
of the FAA's Aviation Rulemaking Advisory Committee (ARAC). Currently, 
these ARAC Working Groups will be focusing their resources on 
expediting the final harmonization of 14 CFR part 25 rules and the 
European Joint Aviation Requirements (JAR)-25. The FAA has encouraged 
ARAC to give this final harmonization effort its highest priority, thus 
increasing the workload of the same parties that normally would be 
reviewing the proposed Propulsion Mega AC. This will leave little time 
or resources for those parties to provide an adequate, thorough review 
of the proposed AC before the comment deadline.
    Additionally, these representatives indicate that new 
recommendations to the FAA may come out of ARAC as a result of the 
activities of these Working Groups, and those recommendations (and 
subsequent rulemaking) may affect the form and content of part of the 
proposed AC.

Withdrawal of the Notice

    The FAA has reviewed and considered these requests from the 
affected public, and has determined that a temporary withdrawal of the 
notice of proposed advisory circular and suspension of the public 
comment period is appropriate at this time. The FAA has placed high 
priority on completing the regulatory harmonization effort in a timely 
manner, and expects the affected industry's resources (via ARAC) to be 
directed primarily towards that goal. Once the harmonization effort has 
concluded, however, the FAA plans to re-issue the notice and re-open 
the period for public comment.
    When formally re-issued, the draft AC likely will not be 
substantially changed from its current form. In fact, approximately 99% 
of the draft AC is comprised of the text of current regulations, 
historical background, advisory circular material, and long-standing 
accepted FAA policy. (The remaining 1% is new policy and advisory 
material not previously released formally to the public.) All of that 
currently-existing material can be found in other documents that have 
been:
     Available to the public for some time, and
     Used by applicants in demonstrating compliance with the 
pertinent regulations, and
     Used by the FAA in finding compliance with regulations.
    Those documents remain valid in their current form.

    Note: The FAA will continue to provide resources to further 
modify the draft AC and subsequent draft versions will be available 
on the Internet at http://www.faa.gov/avr/air/airhome.htm, at the 
link titled ``Draft AC's'' under the ``Available Documents'' drop-
down menu. The public can continue to refer to this draft document 
as a consolidated source reference for currently-existing material.


[[Page 1653]]


    Because the proposed AC likely will not change significantly before 
it is re-issued, and because of the time already allotted to the public 
for review of the proposal, the FAA intends to provide a shortened 
period for public comment when the notice is re-issued.

    Issued in Renton, Washington, on January 5, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-580 Filed 1-10-00; 8:45 am]
BILLING CODE 4910-13-U