[Federal Register Volume 65, Number 135 (Thursday, July 13, 2000)]
[Rules and Regulations]
[Pages 43219-43221]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-17299]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-206-AD; Amendment 39-11813; AD 2000-14-04]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to all Boeing Model 747 series airplanes. This action 
requires a one-time inspection of the fuselage skin adjacent to the 
drag splice fitting to detect cracking, and follow-on actions, if 
necessary. This action is necessary to detect and correct fatigue 
cracking of the fuselage skin, which could result in reduced structural 
integrity of the fuselage, and consequent rapid depressurization of the 
airplane.

DATES: Effective July 28, 2000.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of July 28, 2000.
    Comments for inclusion in the Rules Docket must be received on or 
before September 11, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2000-NM-206-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. 2000-NM-206-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 for Windows or 
ASCII text.
    The service information referenced in this AD may be obtained from 
Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 
98124-2207. This information may be examined at the FAA, Transport 
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at 
the Office of the Federal Register, 800 North Capitol Street, NW., 
suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Rick Kawaguchi, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Transport Airplane Directorate, Seattle 
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056; telephone (425) 227-1153; fax (425) 227-1181.

SUPPLEMENTARY INFORMATION: The FAA has received reports indicating 
that, during regular maintenance of certain Boeing Model 747 series 
airplanes, operators detected cracking of certain areas of the fuselage 
skin adjacent to the drag splice fitting. One operator reported finding 
four skin cracks, which ranged in length from 0.19 to 1.37 inches, 
under the drag splice fitting of the right side underwing. On another 
airplane, an 8.5-inch long crack under the drag splice fitting of the 
left side was detected. Another operator found a 25-inch long diagonal 
crack between body station (BS) 982 and BS 990 at stringers 37L through 
38L. The lower drag splice angle and stringer 38L also were cracked, 
and the BS 1000 bulkhead ring chord was severed. Such conditions, if 
not corrected, could result in reduced structural integrity of the 
fuselage, and consequent rapid depressurization of the airplane.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Service Bulletin 747-
53A2444, Revision 1, dated June 15, 2000, which describes procedures 
for a one-time external detailed visual inspection of the fuselage skin 
adjacent to the drag splice fitting to detect cracking. If no cracking 
is detected, the service bulletin describes procedures for repetitive 
ultrasonic, high frequency eddy current (HFEC), and internal detailed 
visual inspections. The service bulletin also describes procedures for 
a secondary inspection to detect additional cracking, if cracking is 
outside certain limits.

Explanation of the Requirements of the Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other Model 747 series airplanes of the same type 
design, this AD is being issued to detect and correct fatigue cracking 
of certain areas of the fuselage skin, which could result in reduced 
structural integrity of the fuselage, and consequent rapid 
depressurization of the airplane. This AD requires a one-time 
inspection of the fuselage skin adjacent to the drag splice fitting to 
detect cracking, and repair, if necessary. This AD also requires a 
follow-on inspection to detect additional cracking, if cracking is 
outside certain limits.

Interim Action

    This is considered to be interim action until final action is 
identified. At this time the FAA is considering a separate rulemaking 
action to address the procedures for repetitive ultrasonic, HFEC, and 
internal detailed visual inspections of the fuselage skin adjacent to 
the drag splice fitting to detect additional cracking, and repair of 
any cracking detected, as described in the service bulletin. However, 
the planned compliance time for these actions is sufficiently long so 
that notice and opportunity for prior public comment will be 
practicable.
    Due to the urgency of the need to inspect the fleet and repair any 
cracking, this AD will address only the sections in the service 
bulletin that pertain to an initial detailed visual inspection of the 
fuselage skin adjacent to the drag splice fitting to detect cracking, 
repair of any cracking detected, and accomplishment of a secondary 
inspection to detect additional cracking, if necessary.

Differences Between Service Bulletin and This AD

    Operators should note that the service bulletin recommends 
accomplishing the initial detailed visual inspection within 60 days 
(after the release of the service bulletin) for airplanes with more 
than 13,000 flight cycles. The FAA has determined, however, that 
limiting the inspection to airplanes with more than 13,000 flight 
cycles would not address all affected airplanes, in light of the fact 
that the unsafe condition is likely to exist or develop on other Model 
747 series airplanes. In developing an appropriate compliance time for 
all airplanes that are affected by this AD, the FAA considered not only 
the manufacturer's recommendation, but the degree of urgency associated 
with

[[Page 43220]]

addressing the subject unsafe condition, the average utilization of the 
affected fleet, and the time necessary to perform the required 
inspection (approximately 2 hours). In light of all of these factors, 
the FAA finds that, for all Model 747 series airplanes, a compliance 
time of, ``Prior to the accumulation of 13,000 total flight cycles, or 
within 60 days after the effective date of this AD'' for initiating the 
required inspection is warranted, in that it represents an appropriate 
interval of time allowable for affected airplanes to continue to 
operate without compromising safety.

Determination of Rule's Effective Date

    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Submit comments using the following format:
     Organize comments issue-by-issue. For example, discuss a 
request to change the compliance time and a request to change the 
service bulletin reference as two separate issues.
     For each issue, state what specific change to the AD is 
being requested.
     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 rule that might 
suggest a need to modify the 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 that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2000-NM-206-AD.'' The postcard will be date stamped 
and returned to the commenter.

Regulatory Impact

    The regulations adopted herein will 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 final rule does not have federalism 
implications under Executive Order 13132.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and that it is not a ``significant regulatory 
action'' under Executive Order 12866. It has been determined further 
that this action involves an emergency regulation under DOT Regulatory 
Policies and Procedures (44 FR 11034, February 26, 1979). If it is 
determined that this emergency regulation otherwise would be 
significant under DOT Regulatory Policies and Procedures, a final 
regulatory evaluation will be prepared and placed in the Rules Docket. 
A copy of it, if filed, may be obtained from the Rules Docket at the 
location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends 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:

2000-14-04  Boeing: Amendment 39-11813. Docket 2000-NM-206-AD.

    Applicability: All Model 747 series airplanes, 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 (d) 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 fatigue cracking of certain areas of the 
fuselage skin, which could result in reduced structural integrity of 
the fuselage, and consequent rapid depressurization of the airplane; 
accomplish the following:

One-Time Detailed Visual Inspection

    (a) Prior to the accumulation of 13,000 total flight cycles or 
within 60 days after the effective date of this AD, whichever occurs 
later: Perform a one-time external detailed visual inspection of the 
fuselage skin adjacent to the drag splice fitting as illustrated in 
Figure 2 of Boeing Service Bulletin 747-53A2444, Revision 1, dated 
June 15, 2000. If no cracking is detected, no further action is 
required by this AD.

    Note 2: For the purposes of this AD, a detailed visual 
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.''

Corrective Action

    (b) If any cracking is detected during any inspection required 
by this AD, prior to further flight, repair in accordance with a 
method approved by the Manager, Seattle Aircraft Certification 
Office (ACO), FAA, Transport Airplane Directorate; or in accordance 
with data meeting the type certification basis of the airplane 
approved by a Boeing Company Designated Engineering Representative 
who has been authorized by the Manager, Seattle ACO, to make such 
findings. For a repair method to be approved by the Manager, Seattle 
ACO, as required by this paragraph, the approval letter must 
specifically reference this AD.

[[Page 43221]]

Secondary Inspection

    (c) For airplanes on which cracking is detected during the 
inspection required by paragraph (a) of this AD, prior to further 
flight after accomplishment of paragraph (b) of this AD: Determine 
if a secondary inspection of adjacent structure is required, using 
the Logic Diagram illustrated in Figure 1 of Boeing Service Bulletin 
747-53A2444, Revision 1, dated June 15, 2000. If required, prior to 
further flight, accomplish the inspection in accordance with the 
service bulletin.

    Note 3: Inspections and repairs accomplished prior to the 
effective date of this AD in accordance with Boeing Alert Service 
Bulletin 747-53A2444, dated May 25, 2000, are considered acceptable 
for compliance with the applicable action specified in this 
amendment.

Alternative Methods of Compliance

    (d) 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, Seattle ACO. Operators shall submit 
their requests through an appropriate FAA Principal Maintenance 
Inspector, who may add comments and then send it to the Manager, 
Seattle ACO.

    Note 4: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

Special Flight Permits

    (e) 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.

Incorporation by Reference

    (f) The inspections shall be done in accordance with Boeing 
Service Bulletin 747-53A2444, Revision 1, dated June 15, 2000. This 
incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51. Copies may be obtained from Boeing Commercial Airplane Group, 
P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be 
inspected at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington; or at the Office of the Federal 
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
    (g) This amendment becomes effective on July 28, 2000.

    Issued in Renton, Washington, on July 3, 2000.
Vi L. Lipski,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-17299 Filed 7-12-00; 8:45 am]
BILLING CODE 4910-13-U