[Federal Register Volume 61, Number 173 (Thursday, September 5, 1996)]
[Notices]
[Pages 46893-46894]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-22689]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration


Proposed Advisory Circular; Continued Airworthiness Assessments

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of availability of proposed advisory circular and 
request for comments.

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SUMMARY: This notice announces the availability of Advisory Circular 
(AC), no. 33.78-1, Turbine Engine Power-Loss And Instability In Extreme 
Conditions Of Rain And Hail.

DATES: Comments must be received on or before November 7, 1996.

ADDRESSES:  Send all comments on the proposed AC to the Federal 
Aviation Administration, Attn: Engine and Propeller Standards Staff, 
ANE-110, Engine and Propeller Directorate, Aircraft Certification 
Service, 12 New England Executive Park, Burlington, MA, 01803-5299.

FOR FURTHER INFORMATION CONTACT:
Thomas Boudreau, Engine and Propeller Standards Staff, ANE-110, at the 
above address, telephone (617) 238-7117, fax (617) 238-7199.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    A copy of the subject AC may be obtained by contacting the person 
named above under FOR FURTHER INFORMATION CONTACT. Interested persons 
are invited to comment on the proposed AC, and to submit such written 
data, views, or arguments as they desire. Commenters must identify the 
subject to the AC, 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 Engine and Propeller 
Directorate, Aircraft Certification Service, before issuance of the 
final AC.

[[Page 46894]]

Background

    In 1988, the Aerospace Industries Association (AIA) initiated a 
study of airplane turbine engine power-loss and instability phenomena 
that were attributed to operating in inclement weather. AIA, working 
with the Association European des Constructeurs de Materiel Aerospatial 
(AECMA), concluded that a potential flight safety threat exists for 
turbine engines installed on airplanes when operating in an extreme 
rain or hail environment. AIA and AECMA further concluded that the rain 
and hail ingestion requirements contained in section 33.77 do not 
adequately address these threats. Consequently the Federal Aviation 
Administration has issued a notice of proposed rulemaking (61 FR 41688, 
dated August 9, 1996), proposing changes to the water and hail 
ingestion standards.
    This advisory circular, published under the authority granted to 
the Administrator by 49 U.S.C. 106(g), 40113, 44701, 44702, 44704, 
provides guidance for these proposed requirements.


    Issued in Burlington, Massachusetts, on August 27, 1996.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 96-22689 Filed 9-4-96; 8:45 am]
BILLING CODE 4910-13-M