[Federal Register: September 28, 2004 (Volume 69, Number 187)]
[Proposed Rules]
[Page 57884-57886]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr28se04-24]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2004-19175; Directorate Identifier 2003-NM-246-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 747-100B SUD, -200B, -300,
-400, and -400D Series Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for certain Boeing Model 747-100B SUD, -200B, -300, -400, and -400D
series airplanes. This proposed AD would require repetitive inspections
for cracking in fuselage stringers 8L, 8R, 10L, and 10R at body
stations 460, 480, and 500 frame locations; and repair if necessary.
This proposed AD is prompted by findings of cracking in fuselage
stringers 8L, 8R, 10L, and 10R at body stations 460, 480, and 500 frame
locations. We are proposing this AD to detect and correct fatigue
cracking in certain fuselage stringers which, if left undetected, could
result in fuselage skin cracking that reduces the structural integrity
of the skin panel, and consequent rapid depressurization of the
airplane.
DATES: We must receive comments on this proposed AD by November 12,
2004.
ADDRESSES: Use one of the following addresses to submit comments on
this proposed AD.
DOT Docket Web site: Go to http://dms.dot.gov and follow
the instructions for sending your comments electronically.
Government-wide rulemaking Web site: Go to http://www.regulations.gov
and follow the instructions for sending your
comments electronically.
Mail: Docket Management Facility, U.S. Department of
Transportation, 400 Seventh Street, SW., Nassif Building, room PL-401,
Washington, DC 20590.
By fax: (202) 493-2251.
Hand Delivery: Room PL-401 on the plaza level of the
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
You can get the service information identified in this proposed AD
from Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington
98124-2207.
You may examine the AD docket, which contains the proposed AD,
comments received, and any final disposition, on the Internet at http://dms.dot.gov
.
FOR FURTHER INFORMATION CONTACT: Nick Kusz, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425)
917-6432; fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
Docket Management System (DMS)
The FAA has implemented new procedures for maintaining AD dockets
electronically. As of May 17, 2004, new AD actions are posted on DMS
and assigned a docket number. We track each action and assign a
corresponding directorate identifier. The DMS AD docket number is in
the form ``Docket No. FAA-2004-99999.'' The Transport Airplane
Directorate identifier is in the form ``Directorate Identifier 2004-NM-
999-AD.'' Each DMS AD docket also lists the directorate identifier
(``Old Docket Number'') as a cross-reference for searching purposes.
Comments Invited
We invite you to submit any written relevant data, views, or
arguments regarding this proposed AD. Send your comments to an address
listed under ADDRESSES. Include ``Docket No. FAA-2004-19175;
Directorate Identifier 2003-NM-246-AD'' in the subject line of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of the proposed AD. We will
consider all comments submitted by the closing date and may amend the
proposed AD in light of those comments.
We will post all comments we receive, without change, to http://dms.dot.gov
, including any personal information you provide. We will
also post a report summarizing each substantive verbal contact with FAA
personnel concerning this proposed AD. Using the search function of
that website, anyone can find and read the comments in any of our
dockets, including the name of the individual who sent the comment (or
signed the comment on behalf of an association, business, labor union,
etc.). You may review DOT's complete Privacy Act Statement in the
Federal Register published on April 11, 2000 (65 FR 19477-78), or you
may visit http://dms.dot.gov.
We are reviewing the writing style we currently use in regulatory
documents. We are interested in your comments on whether the style of
this document is clear, and your suggestions to improve the clarity of
our communications that affect you. You can get more information about
plain language at http://www.faa.gov/language and http://www.plainlanguage.gov.Examining
the Docket
You may examine the AD docket in person at the Docket Management
Facility office between 9 a.m. and 5 p.m., Monday through Friday,
except Federal holidays. The Docket Management Facility office
(telephone (800) 647-5227) is located on the plaza level of the Nassif
Building at the DOT street address stated in the ADDRESSES section.
Comments will be available in the AD docket shortly after the DMS
receives them.
Discussion
We have received reports of cracking at fuselage stringers 8L, 8R,
10L, and 10R at body station 460, 480, and 500 frame locations. These
stringers are above and below the upper deck windows. The cracking was
found on certain Boeing Model 747-100B SUD, -200B, -300, -400, and -
400D series airplanes having stretched upper decks. Investigation
revealed that the cracking was caused by fatigue. The affected
airplanes had between 29,873 and 90,333 total flight hours and between
9,691 and 25,513 total flight cycles. If the fatigue cracking at the
specified locations is not detected and corrected, the cracking could
grow to include the fuselage skin along the window belt of the upper
deck. Such cracking of the fuselage skin could result in reduced
structural integrity of the skin panel, and consequent rapid
depressurization of the airplane.
Relevant Service Information
We have reviewed Boeing Alert Service Bulletin 747-53A2484, dated
June 26, 2003. The service bulletin describes procedures for doing
repetitive detailed visual inspections of fuselage stringers 8L, 8R,
10L, and 10R at body station 460, 480, and 500 frame locations and
repairing areas with cracking. The repair procedures include installing
new frame clips and new, additional stringer splices and doublers. For
cracking that exceeds the specified limitations, the service bulletin
specifies to install new sections of stringer in accordance with the
747 Structural Repair Manual along with incorporation of repair parts
from the service bulletin. The service bulletin also describes an
optional modification, which eliminates the need for the repetitive
inspections. The optional modification includes procedures for
installing new frame
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clips and new doublers; and repairing, as applicable. Accomplishing the
actions specified in the service bulletin is intended to adequately
address the unsafe condition.
FAA's Determination and Requirements of the Proposed AD
We have evaluated all pertinent information and identified an
unsafe condition that is likely to exist or develop on other airplanes
of this same type design. Therefore, we are proposing this AD, which
would require repetitive inspections for fatigue cracking in fuselage
stringers 8L, 8R, 10L, and 10R at body station 460, 480, and 500 frame
locations; and repair if necessary. The proposed AD also would provide
an optional terminating action for the repetitive inspections. The
proposed AD would require you to use the service information described
previously to perform these actions, except as discussed under
``Differences Between the Proposed AD and Service Information.''
Differences Between the Proposed AD and Service Information
The manufacturer reanalyzed the service problem and has advised the
FAA that the reanalysis has resulted in threshold and repetitive
inspection intervals different from the service bulletin. This resulted
in simplified initial thresholds and an increased number of flight
cycles between repetitive inspections. This difference has been
coordinated with the manufacturer.
Clarification of Inspection Terminology
In this proposed AD, the ``detailed visual inspection'' specified
in the Boeing service bulletin is referred to as a ``detailed
inspection.'' We have included the definition for a ``detailed
inspection'' in a note in this proposed AD.
Costs of Compliance
This proposed AD would affect about 243 Boeing Model 747-100B SUD,
-200B, -300, -400, and -400D series airplanes worldwide. The following
table provides the estimated costs for U.S. operators to comply with
this proposed AD.
Estimated Costs
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Number of U.S.-
Action Work hours Average labor Parts Cost per registered Fleet cost
rate per hour airplane airplanes
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Inspection........................................ 3 $65 None $195 69 $13,455
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Regulatory Findings
We have determined that this proposed AD would not have federalism
implications under Executive Order 13132. This proposed AD would not
have a substantial direct effect 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.
For the reasons discussed above, I certify that the 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. 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.
We prepared a regulatory evaluation of the estimated costs to
comply with this proposed AD. See the ADDRESSES section for a location
to examine the regulatory evaluation.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
The Proposed Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA proposes to amend 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. The FAA amends Sec. 39.13 by adding the following new
airworthiness directive (AD):
Boeing: Docket No. FAA-2004-19175; Directorate Identifier 2003-NM-
246-AD.
Comments Due Date
(a) The Federal Aviation Administration (FAA) must receive
comments on this AD action by November 12, 2004.
Affected ADs
(b) None.
Applicability
(c) This AD applies to certain Boeing Model 747-100B SUD, -200B,
-300, -400, and -400D series airplanes; certificated in any
category; as listed in Boeing Alert Service Bulletin 747-53A2484,
dated June 26, 2003.
Unsafe Condition
(d) This AD was prompted by findings of cracking in fuselage
stringers 8L, 8R, 10L, and 10R at body station 460, 480, and 500
frame locations. We are proposing this AD to detect and correct
fatigue cracking in the specified fuselage stringers which, if left
undetected, could result in fuselage skin cracking that reduces the
structural integrity of the skin panel, and consequent rapid
depressurization of the airplane.
Compliance
(e) You are responsible for having the actions required by this
AD performed within the compliance times specified, unless the
actions have already been done.
Inspection
(f) Do a detailed inspection for cracking in fuselage stringers
8L, 8R, 10L, and 10R at body station 460, 480, and 500 frame
locations, in accordance with Part 1 of the Accomplishment
Instructions in Boeing Alert Service Bulletin 747-53A2484, dated
June 26, 2003. Do the inspections at the applicable time specified
in paragraph (f)(1) or (f)(2) of this AD. Repeat the inspection
thereafter at intervals not to exceed 3,000 flight cycles until the
requirements of paragraph (h) of this AD are accomplished.
(1) For airplanes with 19,000 total flight cycles or less as of
the effective date of this AD: Prior to the accumulation of 8,000
total flight cycles or within 2,000 flight cycles after the
effective date of this AD, whichever is later, not to exceed 20,000
total flight cycles.
(2) For airplanes with more than 19,000 total flight cycles as
of the effective date of this AD: Within 1,000 flight cycles after
the effective date of this AD.
Note 1: For the purposes of this AD, a detailed inspection is:
``An intensive examination of a specific item, installation, or
assembly to detect damage, failure, or irregularity. Available
lighting is normally supplemented with a direct source of good
lighting at an intensity deemed appropriate. Inspection aids such as
mirror, magnifying lenses, etc., may be necessary. Surface cleaning
and elaborate procedures may be required.''
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Repair
(g) If any cracking is found during any inspection required by
paragraph (f) of this AD: Before further flight, repair the affected
stringer in accordance with Part 2 of the Accomplishment
Instructions of Boeing Alert Service Bulletin 747-53A2484, dated
June 26, 2003. Repair terminates the repetitive inspections required
by paragraph (f) of this AD for only the repaired stringer/frame
location.
Optional Terminating Action
(h) Installing new frame clips and new doublers; and repairing
as applicable; in accordance with Part 3 of the Accomplishment
Instructions of Boeing Alert Service Bulletin 747-53A2484, dated
June 26, 2003, terminates the repetitive inspections required by
this AD.
Alternative Methods of Compliance (AMOCs)
(i) The Manager, Seattle Aircraft Certification Office (ACO),
FAA, has the authority to approve AMOCs for this AD, if requested
using the procedures found in 14 CFR 39.19.
Issued in Renton, Washington, on September 20, 2004.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 04-21648 Filed 9-27-04; 8:45 am]
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