[Federal Register: November 26, 2003 (Volume 68, Number 228)]
[Proposed Rules]
[Page 66384-66386]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr26no03-17]
-----------------------------------------------------------------------
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).
-----------------------------------------------------------------------
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: 9-anm-nprmcomment@faa.gov. 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
------------------------------------------------------------------------
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.
------------------------------------------------------------------------
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