[Federal Register Volume 68, Number 228 (Wednesday, November 26, 2003)]
[Proposed Rules]
[Pages 66384-66386]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-29572]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NM-288-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747-400F 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 Boeing Model 747-400F 
series airplanes. This proposal would require repetitive detailed and 
general visual inspections of the external fuselage skin for cracks; 
various inspections of the affected area where cracks are found to 
determine the extent of the damage; and repair of cracks. This action 
is necessary to detect and correct fatigue cracks in the fuselage skin 
and frame shear tie assemblies, which could propagate and result in 
possible in-flight decompression of the airplane. This action is 
intended to address the identified unsafe condition.

DATES: Comments must be received by January 12, 2004.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2002-NM-288-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9 a.m. and 3 p.m., Monday through Friday, except 
Federal holidays. Comments may be submitted via fax to (425) 227-1232. 
Comments may also be sent via the Internet using the following address: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 2002-NM-288-AD'' in the subject line and need not 
be submitted in triplicate. Comments sent via the Internet as attached 
electronic files must be formatted in Microsoft Word 97 or 2000 or 
ASCII text.
    The service information referenced in the proposed rule may be 
obtained from Boeing Commercial Airplane Group, PO Box 3707, Seattle, 
Washington 98124-2207. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Candice Gerretsen, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
917-6428; fax (425) 917-6590.

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 action may be changed in 
light of the comments received.
    Submit comments using the following format:
    [sbull] Organize comments issue-by-issue. For example, discuss a 
request to change the compliance time and a

[[Page 66385]]

request to change the service bulletin reference as two separate 
issues.
    [sbull] For each issue, state what specific change to the proposed 
AD is being requested.
    [sbull] Include justification (e.g., reasons or data) for each 
request.
    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 action must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2002-NM-288-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-114, Attention: Rules 
Docket No. 2002-NM-288-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received reports indicating that cracking was noticed 
during production of three Boeing Model 747-400F series airplanes. The 
cracking occurred on the section 42 skin panel assemblies at several 
fastener locations common to the body station 800 frame shear tie 
between stringers 13 and 15 on both the left and right sides of the 
airplanes. The maximum crack length was approximately 0.5 inch. Further 
investigation revealed that the cracks resulted from cyclic fatigue due 
to insufficient support at the tool attachment locations for the 
section 42 skin panel assemblies during shipment. Fatigue cracks in the 
fuselage skin and frame shear assemblies, if not detected and 
corrected, could propagate and result in undetected cracks and possible 
in-flight decompression of the airplane.
    Boeing Model 747-400F series airplanes after line number 1286 have 
been inspected and show no damage. Section 42 skin panel assemblies on 
future Model 747-400F series airplanes will be shipped in a modified 
shipping fixture that provides improved support to prevent future 
damage. The section 42 skin panel assemblies for Boeing Model 747-100, 
-200B, -200C, -100B, -300, -100B SUD, -400, and ``400D series airplanes 
have different shipping fixtures that provide adequate support. 
Therefore, these airplanes are not subject to the same unsafe condition 
identified in the 747-400F series airplanes having line numbers 968 
through 1286, inclusive.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Special Attention Service 
Bulletin 747-53-2480, dated March 28, 2002, which describes procedures 
for repetitive detailed and general visual inspections of the external 
fuselage skin for cracks; various inspections of the affected area 
where cracks are found to determine the extent of the damage; and 
repair of cracks. Repair of a crack eliminates the need for the 
repetitive detailed and general visual inspections for that repair area 
only. Accomplishment of the actions specified in the service bulletin 
is intended to adequately address the identified unsafe condition.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other products of this same type design, the 
proposed AD would require accomplishment of the actions specified in 
the service bulletin described previously, except as discussed below.

Differences Between Proposed Rule and Service Bulletin

    Although the service bulletin specifies that operators may contact 
the manufacturer for an alternate repair for certain cracking 
conditions, this proposed AD would require operators to repair those 
conditions per a method approved by the FAA or per data meeting the 
type certification basis of the airplane approved by a Boeing Company 
Designated Engineering Representative who has been authorized by the 
FAA to make such findings.

Cost Impact

    There are approximately 72 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 12 airplanes of U.S. registry 
would be affected by this proposed AD, that it would take approximately 
1 work hour per airplane to accomplish the proposed inspections, and 
that the average labor rate is $65 per work hour. Based on these 
figures, the cost impact of the proposed AD on U.S. operators is 
estimated to be $780, or $65 per airplane, per inspection cycle.
    The cost impact figure discussed above is 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 proposed AD were not adopted. The cost impact 
figures discussed in AD rulemaking actions represent only the time 
necessary to perform the specific actions actually required by the AD. 
These figures typically do not include incidental costs, such as the 
time required to gain access and close up, planning time, or time 
necessitated by other administrative actions. Manufacturer warranty 
remedies may be available for labor costs associated with this proposed 
AD. As a result, the costs attributable to the proposed AD may be less 
than stated above.

Regulatory Impact

    The regulations proposed herein 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. Therefore, it 
is determined that this proposal would not have federalism implications 
under Executive Order 13132.
    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:


[[Page 66386]]


    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:

Boeing: Docket 2002-NM-288-AD.

    Applicability: Model 747-400F series airplanes, having line 
numbers 968 through 1286 inclusive, certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To detect and correct fatigue cracks in the fuselage skin and 
frame shear tie assemblies, which could propagate and result in 
possible in-flight decompression of the airplane, accomplish the 
following:

Service Bulletin Reference

    (a) The term ``service bulletin,'' as used in this AD, means the 
Accomplishment Instructions of Boeing Special Attention Service 
Bulletin 747-53-2480, dated March 28, 2002.

Compliance Time

    (b) At the later compliance time specified in paragraphs (b)(1) 
and (b)(2) of this AD, do the inspections specified in paragraph (c) 
of this AD.
    (1) Within 6,000 flight cycles after the date of issuance of the 
original Airworthiness Certificate or date of issuance of the Export 
Certificate of Airworthiness, whichever comes first.
    (2) Within 3,000 flight cycles after the effective date of this 
AD.

Repetitive Inspections

    (c) Perform both inspections of the external fuselage skin as 
shown in Table 1 of this AD, per the service bulletin. Repeat the 
inspections thereafter at intervals not to exceed 3,000 flight 
cycles.

                    Table 1.--Inspection Requirements
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           Type of inspection                    Area to inspect
------------------------------------------------------------------------
(1) Detailed...........................  Inspect the skin surface for
                                          cracks initiating from the
                                          shear tie fasteners (14
                                          locations on each side) common
                                          to the body station 800 frame
                                          between stringers S-13 and S-
                                          15 on both the left and right
                                          sides of the airplane.
(2) General............................  Inspect the skin surface at all
                                          fastener locations for cracks
                                          between body stations 780 to
                                          800 and stringers S-13 through
                                         S-15 on both the left and right
                                          sides of the airplane.
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    Note 1: For the purposes of this AD, a detailed inspection is 
defined as: ``An intensive visual examination of a specific 
structural area, system, installation, or assembly to detect damage, 
failure, or irregularity. Available lighting is normally 
supplemented with a direct source of good lighting at intensity 
deemed appropriate by the inspector. Inspection aids such as mirror, 
magnifying lenses, etc., may be used. Surface cleaning and elaborate 
access procedures may be required.''


    Note 2: For the purposes of this AD, a general visual inspection 
is defined as: ``A visual examination of an interior or exterior 
area, installation, or assembly to detect obvious damage, failure, 
or irregularity. This level of inspection is made from within 
touching distance unless otherwise specified. A mirror may be 
necessary to enhance visual access to all exposed surfaces in the 
inspection area. This level of inspection is made under normally 
available lighting conditions such as daylight, hangar lighting, 
flashlight, or droplight and may require removal or opening of 
access panels or doors. Stands, ladders, or platforms may be 
required to gain proximity to the area being checked.''

Crack Findings: Inspections and Repair

    (d) If any crack is found during any inspection required by 
paragraph (c) of this AD, before further flight, do the actions 
specified in paragraphs (d)(1) and (d)(2) of this AD.
    (1) Perform inspections of the affected area to determine the 
extent of the crack using the following applicable inspection 
methods, per the service bulletin: detailed inspection; open-hole 
high frequency eddy current (HFEC) inspection; surface HFEC 
inspection; and dye penetrant inspection.
    (2) Repair any crack per the service bulletin. Where the service 
bulletin specifies contacting Boeing for an alternate repair method: 
Before further flight, repair per a method approved by the Manager, 
Seattle Aircraft Certification Office (ACO), FAA, or per data 
meeting the type certification basis of the airplane approved by a 
Boeing Company DER who has been authorized by the Manager, Seattle 
ACO, to make such findings.

Terminating Action for Repaired Area

    (e) Accomplishment of the repair per paragraph (d)(2) of this AD 
ends the repetitive inspection requirements of paragraph (c) of this 
AD for that repaired area only.

Alternative Methods of Compliance

    (f) In accordance with 14 CFR 39.19, the Manager, ACO, FAA, is 
authorized to approve alternative methods of compliance (AMOCs) for 
this AD.

    Issued in Renton, Washington, on November 20, 2003.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 03-29572 Filed 11-25-03; 8:45 am]
BILLING CODE 4910-13-P