[Federal Register Volume 62, Number 62 (Tuesday, April 1, 1997)]
[Proposed Rules]
[Pages 15439-15441]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-8251]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 96-NM-172-AD]
RIN 2120-AA64
Airworthiness Directives; Airbus Model A310 and A300-600 Series
Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the adoption of a new airworthiness
directive (AD) that is applicable to certain Airbus Model A310 and
A300-600 series airplanes. This proposal would require a visual
inspection to detect cracks in the aft mount beam assembly of the
engine; and replacement of any cracked beam with a new beam or beam
assembly. The proposal also would require a fluorescent penetrant
inspection to detect cracks in the aft mount beam assembly of the
engine, and various follow-on actions. This proposal is prompted by
reports indicating that, apparently due to manufacturing defects during
the forging process, cracking was found in two engine aft mount beams.
The actions specified by the proposed AD are intended to detect and
correct such cracking, which could result in reduced structural
integrity of the aft mount beam assembly of the engine.
DATES: Comments must be received by May 12, 1997.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 96-NM-172-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056. Comments may be inspected at this
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except
Federal holidays.
The service information referenced in the proposed rule may be
obtained from Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707
Blagnac Cedex, France; or Pratt & Whitney, 400 Main Street, East
Hartford, Connecticut 06108. This information may be examined at the
FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington.
FOR FURTHER INFORMATION CONTACT: Charles Huber, Aerospace Engineer,
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206)
227-2589; fax (206) 227-1149.
SUPPLEMENTARY INFORMATION:
Comments Invited
Interested persons are invited to participate in the making of the
proposed rule by submitting such written data, views, or arguments as
they may desire. Communications shall identify the Rules Docket number
and be submitted in triplicate to the address specified above. All
communications received on or before the closing date for comments,
specified above, will be considered before taking action on the
proposed rule.
The proposals contained in this notice may be changed in light of
the comments received.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the proposed rule. All
comments submitted will be available, both before and after the closing
date for comments, in the Rules Docket for examination by interested
persons. A report summarizing each FAA-public contact concerned with
the substance of this proposal will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this notice must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 96-NM-172-AD.'' The postcard will be date stamped and
returned to the commenter.
Availability of NPRMs
Any person may obtain a copy of this NPRM by submitting a request
to the FAA, Transport Airplane Directorate, ANM-103, Attention: Rules
Docket No. 96-NM-172-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
The Direction Generale de l'Aviation Civile (DGAC), which is the
[[Page 15440]]
airworthiness authority for France, notified the FAA that an unsafe
condition may exist on certain Airbus Model A310 and A300-600 series
airplanes. The DGAC advises that it has received reports indicating
that, during overhaul maintenance following a fluorescent penetrant
inspection, cracking was found in two engine aft mount beams on Airbus
Model A310 series airplanes. One of the beams had a long surface crack,
and the other beam had smaller branch cracks. The apparent cause of
such cracking has been attributed to the forging process during
manufacturing. Cracking in the aft mount beam assembly of the engine,
if not detected and corrected, could result in reduced structural
integrity of the aft mount beam assembly.
Explanation of Relevant Service Information
Pratt & Whitney has issued Alert Service Bulletin PW7R4 A71-129,
Revision 1, dated August 30, 1995, and Service Bulletin PW4NAC A71-149,
Revision 1, dated August 30, 1995. These service bulletins describe
procedures for performing a visual inspection to detect cracks in the
aft mount beam assembly of the engine; and replacement of any cracked
beam with a new beam or beam assembly. These service bulletins also
describe procedures for performing a fluorescent penetrant inspection
to detect cracks in the aft mount beam assembly of the engine, and
various follow-on actions. (These follow-on actions include an eddy
current inspection, reidentification of the beam, and replacement of
any cracked beam.) The DGAC classified these service bulletins as
mandatory and issued French airworthiness directive (C/N) 96-020-
195(B), dated January 31, 1996, in order to assure the continued
airworthiness of these airplanes in France.
FAA's Conclusions
These airplane models are manufactured in France and are type
certificated for operation in the United States under the provisions of
Sec. 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the
applicable bilateral airworthiness agreement. Pursuant to this
bilateral airworthiness agreement, the DGAC has kept the FAA informed
of the situation described above. The FAA has examined the findings of
the DGAC, reviewed all available information, and determined that AD
action is necessary for products of this type design that are
certificated for operation in the United States.
Explanation of Requirements of Proposed Rule
Since an unsafe condition has been identified that is likely to
exist or develop on other airplanes of the same type design registered
in the United States, the proposed AD would require a visual inspection
to detect cracks in the aft mount beam assembly of the engine; and
replacement of any cracked beam with a new beam or beam assembly. The
proposed AD also would require a fluorescent penetrant inspection to
detect cracks in the aft mount beam assembly of the engine, and various
follow-on actions. The actions would be required to be accomplished in
accordance with the applicable service bulletin described previously.
Cost Impact
The FAA estimates that 8 Airbus Model A310 and A300-6000 series
airplanes of U.S. registry would be affected by this proposed AD.
It would take approximately 2 work hours per airplane to accomplish
the proposed visual inspection, at an average labor rate of $60 per
work hour. Based on these figures, the cost impact of the visual
inspection proposed by this AD on U.S. operators is estimated to be
$960, or $120 per airplane.
It would take approximately 34 work hours per airplane to
accomplish the proposed fluorescent penetrant inspection, at an average
labor rate of $60 per work hour. Based on these figures, the cost
impact of the flourescent penetrant inspection proposed by this AD on
U.S. operators is estimated to be $16,320, or $2,040 per airplane.
The cost impact figures discussed above are based on assumptions
that no operator has yet accomplished any of the proposed requirements
of this AD action, and that no operator would accomplish those actions
in the future if this AD were not adopted.
Regulatory Impact
The regulations proposed herein would not have substantial direct
effects on the States, on the relationship between the national
government and the States, or on the distribution of power and
responsibilities among the various levels of government. Therefore, in
accordance with Executive Order 12612, it is determined that this
proposal would not have sufficient federalism implications to warrant
the preparation of a Federalism Assessment.
For the reasons discussed above, I certify that this proposed
regulation (1) is not a ``significant regulatory action'' under
Executive Order 12866; (2) is not a ``significant rule'' under the DOT
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979);
and (3) if promulgated, will not have a significant economic impact,
positive or negative, on a substantial number of small entities under
the criteria of the Regulatory Flexibility Act. A copy of the draft
regulatory evaluation prepared for this action is contained in the
Rules Docket. A copy of it may be obtained by contacting the Rules
Docket at the location provided under the caption ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
The Proposed Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration proposes to amend
part 39 of the Federal Aviation Regulations (14 CFR part 39) as
follows:
PART 39--AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
Airbus Industrie: Docket 96-NM-172-AD.
Applicability: Model A310 and A300-600 series airplanes,
equipped with Pratt & Whitney Model JT9D-7R4D1, JT9D-7R4E1, JT9D-
7R4H1, PW4151, PW4156A, PW4158 engines; certificated in any
category.
Note 1: This AD applies to each airplane identified in the
preceding applicability provision, regardless of whether it has been
modified, altered, or repaired in the area subject to the
requirements of this AD. For airplanes that have been modified,
altered, or repaired so that the performance of the requirements of
this AD is affected, the owner/operator must request approval for an
alternative method of compliance in accordance with paragraph (c) of
this AD. The request should include an assessment of the effect of
the modification, alteration, or repair on the unsafe condition
addressed by this AD; and, if the unsafe condition has not been
eliminated, the request should include specific proposed actions to
address it.
Compliance: Required as indicated, unless accomplished
previously.
To detect and correct cracking in the aft mount beam assembly of
the engine, which could result in reduced structural integrity of
the aft mount beam assembly, accomplish the following:
(a) Within 500 flight hours after the effective date of this AD,
perform a visual inspection to detect cracks in the aft mount
[[Page 15441]]
beam assembly of the engine, in accordance with Part 1 of the
Accomplishment Instructions of Pratt & Whitney Alert Service
Bulletin PW7R4 A71-129, Revision 1, dated August 30, 1995, or Pratt
& Whitney Service Bulletin PW4NAC A71-149, Revision 1, dated August
30, 1995; as applicable.
(1) If no crack is detected, no further action is required by
this paragraph.
(2) If any crack is detected, prior to further flight, replace
the cracked beam with a new beam or beam assembly, in accordance
with the applicable service bulletin.
(b) Within 4,000 flight cycles after the effective date of this
AD, perform a fluorescent penetrant inspection to detect cracks in
the aft mount beam assembly of the engine, in accordance with Part 2
of the Accomplishment Instructions of Pratt & Whitney Alert Service
Bulletin PW7R4 A71-129, Revision 1, dated August 30, 1995, or Pratt
& Whitney Service Bulletin PW4NAC A71-149, Revision 1, dated August
30, 1995; as applicable.
(1) If no crack is detected, prior to further flight, perform an
eddy current inspection to detect cracks in the aft mount beam
assembly of the engine, in accordance with the applicable service
bulletin.
(i) If no crack is detected, prior to further flight, reidentify
the beam in accordance with the applicable service bulletin.
(ii) If any crack is detected, prior to further flight, replace
the cracked beam with a new beam or beam assembly, in accordance
with the applicable service bulletin.
(2) If any crack is detected, prior to further flight, replace
the cracked beam with a new beam or beam assembly, in accordance
with the applicable service bulletin.
(c) An alternative method of compliance or adjustment of the
compliance time that provides an acceptable level of safety may be
used if approved by the Manager, Standardization Branch, ANM-113,
FAA, Transport Airplane Directorate. Operators shall submit their
requests through an appropriate FAA Principal Maintenance Inspector,
who may add comments and then send it to the Manager,
Standardization Branch, ANM-113.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Standardization Branch, ANM-113.
(d) Special flight permits may be issued in accordance with
sections 21.197 and 21.199 of the Federal Aviation Regulations (14
CFR 21.197 and 21.199) to operate the airplane to a location where
the requirements of this AD can be accomplished.
Issued in Renton, Washington, on March 26, 1997.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 97-8251 Filed 3-31-97; 8:45 am]
BILLING CODE 4910-13-U
