[Federal Register Volume 63, Number 204 (Thursday, October 22, 1998)]
[Notices]
[Pages 56690-56691]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-28326]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration


Advisory Circular; Manufacturing Process of Premium Quality 
Titanium Alloy Rotating Engine Components

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of issuance of Advisory Circular (AC).

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SUMMARY: This notice announces the issuance of Advisory Circular (AC), 
No. 33.15-1, Manufacturing Process of Premium Quality Titanium Alloy 
Rotating Engine Components. This AC is provides guidance and 
information for compliance pertaining to the materials suitability and 
durability requirements, symbol Sec. 33.15, as applicable to the 
manufacture of titanium alloy high energy rotating parts of aircraft 
engines. Like all AC material, this AC is not, in itself, mandatory and 
does not constitute a regulation. It is issued to provide an acceptable 
means, but not the only means, of compliance with symbol Sec. 33.15. 
While these guidelines are not mandatory, they are derived from 
extensive Federal Aviation Administration (FAA) and industry experience 
in determining compliance with the pertinent regulations.

DATES: Advisory Circular No. 33.15-1, was issued by the New England 
Aircraft Certification Service, Engine and Propeller Directorate on 
September 22, 1998.

FOR FURTHER INFORMATION CONTACT: Tim Mouzakis, Engine and Propeller 
Standards Staff, ANE-110, 12 New England Executive Park, Burlington, 
MA, 01803, telephone (781) 238-7114, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

Background

    Advisory Circulars 21-1B, 21-6A, 21-9A, 21-27, and 21.303-1A, 
provide a means to obtain and maintain production approvals; however, 
these documents do not fully cover the manufacturing processes used in 
the manufacture of premium quality titanium alloy forged rotating 
components for type certificated turbine engines. This AC, therefore, 
provides supplemental guidance for the establishment of manufacturing 
processes, in-process material and component inspections, and finished 
component inspections, for manufacture of premium quality titanium 
alloy forged rotating components, such as disks, spacers, hubs, shafts, 
spools and impellers, but not blades.
    Interested parties were given the opportunity to review and comment 
on the draft AC during the proposal and development phases. Notice was 
published in the Federal Register on July 17, 1997 (62 FR 38338), to 
announce the availability of, and comment to the draft AC.
    This advisory circular, published under the authority granted to 
the

[[Page 56691]]

Administrator by 49 U.S.C. 106(g), 4113, 44701-44702, 44704, provides 
guidance for these requirements.

    Issued in Burlington, Massachusetts, on September 22, 1998.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 98-28326 Filed 10-21-98; 8:45 am]
BILLING CODE 4910-13-P