[Federal Register Volume 67, Number 53 (Tuesday, March 19, 2002)]
[Rules and Regulations]
[Pages 12464-12466]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-6329]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NM-32-AD; Amendment 39-12678; AD 2002-06-02]
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 repetitive inspections for cracking of the upper skin of the 
horizontal stabilizer center section and the rear spar upper chord, and 
repair, if necessary. This action is necessary to find and fix such 
cracking, which could lead to reduced structural capability of the 
horizontal stabilizer center section, and result in loss of 
controllability of the airplane. This action is intended to address the 
identified unsafe condition.

DATES: Effective April 3, 2002.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of April 3, 2002.
    Comments for inclusion in the Rules Docket must be received on or 
before May 20, 2002.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2002-NM-32-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-32-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: Tamara Anderson, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2771; fax (425) 227-1181.

SUPPLEMENTARY INFORMATION: The FAA has received a report that a 3.5-
inch crack was found in the upper skin of the horizontal stabilizer 
center section on a Boeing Model 747SR series airplane. The crack ran 
forward from the rear spar at left buttock line (LBL) 37.8. While the 
area where the crack was found is subject to inspections per a certain 
Supplemental Structural Inspection Document (SSID), the airplane on 
which the crack was found was not an SSID candidate. Such cracking, if 
not fixed, could lead to reduced structural capability of the 
horizontal stabilizer center section, which could result in loss of 
controllability of the airplane.

[[Page 12465]]

    The subject area on all Model 747 series airplanes is similar to 
that on the affected Model 747SR series airplane. Therefore, all of 
these airplanes may be subject to the same unsafe condition.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Alert Service Bulletin 
747-55A2050, dated February 28, 2002, which describes procedures for 
repetitive detailed and high frequency eddy current (HFEC) inspections 
for cracking of the upper skin of the horizontal stabilizer center 
section and the rear spar upper chord. The procedures include a 
detailed visual inspection for cracking of the upper horizontal skin 
and of the vertical and horizontal flanges of the rear spar upper 
chord, and an HFEC inspection for cracking of the vertical flange of 
the upper chord where a detailed visual inspection is impeded by 
stiffeners, brackets, or sealant. The service bulletin specifies to 
contact Boeing for repair of any crack that is found. Accomplishment of 
the actions specified in the service bulletin is intended to adequately 
address the identified unsafe condition.

Explanation of the Requirements of the Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design, this AD is 
being issued to find and fix cracking of the upper skin of the 
horizontal stabilizer center section and the rear spar upper chord, 
which could lead to reduced structural capability of the horizontal 
stabilizer center section, and result in loss of controllability of the 
airplane. This AD requires accomplishment of the actions specified in 
the service bulletin described previously, except as discussed below.

Differences Between This AD and the Service Bulletin

    Operators should note that, although the service bulletin specifies 
that the manufacturer may be contacted for disposition of repair 
conditions, this AD requires the repair of those conditions to be 
accomplished 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 
Manager, Seattle Aircraft Certification Office, to make such findings.

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 2002-NM-32-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:

2002-06-02  Boeing: Amendment 39-12678. Docket 2002-NM-32-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

[[Page 12466]]

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 find and fix cracking of the upper skin of the horizontal 
stabilizer center section and the rear spar upper chord, which could 
lead to reduced structural capability of the horizontal stabilizer 
center section, and result in loss of controllability of the 
airplane, accomplish the following:

Repetitive Inspections

    (a) Before the accumulation of 24,000 total flight cycles, or 
within 90 days after the effective date of this AD, whichever occurs 
later: Do detailed and high frequency eddy current (HFEC) 
inspections, as applicable, for cracking of the upper skin of the 
horizontal stabilizer center section and the rear spar upper chord, 
according to the Work Instructions and Figure 1 of Boeing Alert 
Service Bulletin 747-55A2050, dated February 28, 2002. (The 
inspection procedures include a detailed inspection for cracking of 
the upper horizontal skin and of the vertical and horizontal flanges 
of the rear spar upper chord, and an HFEC inspection for cracking of 
the vertical flange of the upper chord where a detailed inspection 
is impeded by the presence of stiffeners, brackets, or sealant.) 
After doing the initial inspections, repeat the inspections every 
1,000 flight cycles.

    Note 2: 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.''

Repair

    (b) If any cracking is found during any inspection per paragraph 
(a) of this AD: 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 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 Manager's approval letter 
must specifically reference this AD.

Alternative Methods of Compliance

    (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, 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 3: 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

    (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.

Incorporation by Reference

    (e) The actions shall be done in accordance with Boeing Alert 
Service Bulletin 747-55A2050, dated February 28, 2002. 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.

Effective Date

    (f) This amendment becomes effective on April 3, 2002.

    Issued in Renton, Washington, on March 11, 2002.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 02-6329 Filed 3-18-02; 8:45 am]
BILLING CODE 4910-13-P