[Federal Register Volume 71, Number 134 (Thursday, July 13, 2006)]
[Proposed Rules]
[Pages 39600-39603]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E6-11019]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-25327; Directorate Identifier 2006-NM-116-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747-100, 747-100B, 747-
100B SUD, 747-200B, 747-300, 747-400, 747-400D, and 747SR Series 
Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to revise an existing airworthiness directive 
(AD) that applies to certain Boeing Model 747-100, 747-100B, 747-100B 
SUD, 747-200B, 747-300, 747-400, 747-400D, and 747SR series airplanes. 
The existing AD currently requires repetitive inspections to detect 
cracking of certain lower lobe fuselage frames, and repair if 
necessary. This proposed AD would specify appropriate service 
information for certain corrective actions. This proposed AD results 
from reports indicating that fatigue cracks were found in lower lobe 
frames on the left side of the fuselage. We are proposing this AD to 
detect and correct fatigue cracking of certain lower lobe fuselage

[[Page 39601]]

frames, which could lead to fatigue cracks in the fuselage skin, and 
consequent rapid decompression of the airplane.

DATES: We must receive comments on this proposed AD by August 28, 2006.

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.
     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.
    Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207, for service information identified in this 
proposed AD.

FOR FURTHER INFORMATION CONTACT: Ivan Li, Aerospace Engineer, Airframe 
Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind 
Avenue, SW., Renton, Washington 98055-4056; telephone (425) 917-6437; 
fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to submit any relevant written data, views, or 
arguments regarding this proposed AD. Send your comments to an address 
listed in the ADDRESSES section. Include docket number ``Docket No. 
FAA-2006-25327; Directorate Identifier 2006-NM-116-AD'' at the 
beginning 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 received 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 Web site, anyone can find and read the comments in a docket, 
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 the 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.

Examining the Docket

    You may examine the AD docket on the Internet at http://dms.dot.gov, or 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 Docket Management System 
receives them.

Discussion

    On April 20, 2006, we issued AD 2006-09-06, amendment 39-14576 (71 
FR 25926, May 3, 2006), for certain Boeing Model 747-100, 747-100B, 
747-100B SUD, 747-200B, 747-300, 747-400, 747-400D, and 747SR series 
airplanes. That AD requires repetitive inspections to detect cracking 
of certain lower lobe fuselage frames, and repair if necessary. That AD 
resulted from reports indicating that fatigue cracks were found in 
lower lobe frames on the left side of the fuselage. We issued that AD 
to detect and correct fatigue cracking of certain lower lobe fuselage 
frames, which could lead to fatigue cracks in the fuselage skin, and 
consequent rapid decompression of the airplane.

Actions Since Existing AD Was Issued

    Since we issued AD 2006-09-06, an operator questioned the addition 
of a reference to Boeing Service Bulletin 747-53A2349, Revision 2, 
dated April 3, 2003, in paragraph (h)(1) of that AD. A service bulletin 
reference in that paragraph was not included in the Notice of Proposed 
Rulemaking (NPRM) for AD 2006-09-06, but was added in the final rule to 
clarify the requirements of that paragraph. However, the service 
bulletin referenced in that paragraph should be Boeing Alert Service 
Bulletin 747-53A2408, Revision 1, dated April 4, 2002, rather than 
Boeing Service Bulletin 747-53A2349, Revision 2. Therefore, we have 
revised paragraph (h)(1) of this NPRM to refer to the correct service 
bulletin.

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. For this reason, we are proposing this AD, 
which would revise AD 2006-09-06 and would retain the requirements of 
the existing AD. This proposed AD would revise the service information 
referenced in paragraph (h)(1).

Explanation of Editorial Change

    We have revised the reference to the Boeing 747-400 Structural 
Repair Manual in paragraph (h)(1)(i) of this proposed AD. The paragraph 
applies to Group 1 airplanes and should refer to the Boeing 747 
Structural Repair Manual because Boeing 747-400 series airplanes are 
not in Group 1.

Costs of Compliance

    There are about 681 airplanes of the affected design in the 
worldwide fleet. This proposed AD would affect about 99 airplanes of 
U.S. registry. The new requirements of this proposed AD add no 
additional economic burden. The current costs for this AD are repeated 
for the convenience of affected operators, as follows:
    The actions in this proposed AD take about 2 work hours per 
airplane, at an average labor rate of $80 per work hour. Based on these 
figures, the estimated cost of both the retained and proposed actions 
for U.S. operators is $15,840, or $160 per airplane, per inspection 
cycle.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
subtitle VII, part A, subpart III, section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

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

[[Page 39602]]

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 and place it in the AD docket. 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 Federal Aviation Administration (FAA) amends Sec.  39.13 by 
removing amendment 39-14576 (71 FR 25926, May 3, 2006) and adding the 
following new airworthiness directive (AD):

Boeing: Docket No. FAA-2006-25327; Directorate Identifier 2006-NM-
116-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by August 
28, 2006.

Affected ADs

    (b) This AD revises AD 2006-09-06.

Applicability

    (c) This AD applies to Boeing Model 747-100, 747-100B, 747-100B 
SUD, 747-200B, 747-300, 747-400, 747-400D, and 747SR series 
airplanes, certificated in any category, as identified in Boeing 
Alert Service Bulletin 747-53A2408, Revision 1, dated April 4, 2002.

Unsafe Condition

    (d) This AD results from reports indicating that fatigue cracks 
were found in lower lobe frames on the left side of the fuselage. We 
are issuing this AD to detect and correct fatigue cracking of 
certain lower lobe fuselage frames, which could lead to fatigue 
cracks in the fuselage skin, and consequent rapid decompression 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.

Restatement of the Requirements of AD 99-07-12, With Additional 
Information for Group 2 Airplanes

Initial Inspections

    (f) For airplanes on which the initial detailed internal 
inspection of the Section 46 lower lobe frames required by paragraph 
(f)(2) or (i)(2) of AD 2005-20-30, amendment 39-14327, has not been 
accomplished: Perform a detailed visual inspection to detect 
cracking of the lower lobe fuselage frames from Body Station 1820 to 
Body Station 2100, in accordance with the Accomplishment 
Instructions of Boeing Alert Service Bulletin 747-53A2408, dated 
April 25, 1996; or Boeing Alert Service Bulletin 747-53A2408, 
Revision 1, dated April 4, 2002; as applicable; at the later of the 
applicable times specified in paragraph (f)(1), (f)(2), or (f)(3) of 
this AD.
    (1) For all airplanes: Prior to the accumulation of 15,000 total 
flight cycles; or
    (2) For Group 1 airplanes identified in Revision 1 of the 
service bulletin: Within 1,500 flight cycles or 18 months after May 
5, 1999 (the effective date of AD 99-07-12), whichever occurs first.
    (3) For Group 2 airplanes identified in Revision 1 of the 
service bulletin: Within 1,500 flight cycles or 18 months after June 
7, 2006, whichever occurs first.

    Note 1: Paragraphs (f)(2) and (i)(2) of AD 2005-20-30 require a 
detailed inspection to detect cracks in the Section 46 lower lobe 
frames, in accordance with Boeing Service Bulletin 747-53A2349, 
Revision 2, dated April 3, 2003. The initial inspection is required 
prior to the accumulation of 22,000 total flight cycles; or within 
1,000 flight cycles after June 11, 1993 (the effective date of AD 
93-08-12, amendment 39-8559), or November 16, 2005 (the effective 
date of AD 2005-20-30), depending on previous inspections 
accomplished; whichever occurs later.


    Note 2: 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.''

Repetitive Inspections

    (g) If no cracking is detected during the inspection required by 
paragraph (f) of this AD, repeat the inspection thereafter at 
intervals not to exceed 3,000 flight cycles.

Corrective Actions

    (h) If any cracking is detected during any inspection required 
by paragraph (f) of this AD, prior to further flight, accomplish 
paragraphs (h)(1) and (h)(2) of this AD:
    (1) Within 20 inches of the crack location on the frame, perform 
a detailed inspection of the adjacent structure to detect cracking. 
As of the effective date of this AD, the detailed inspection must be 
done in accordance with Boeing Alert Service Bulletin 747-53A2408, 
Revision 1, dated April 4, 2002. If any cracking is detected during 
any detailed inspection done in accordance with paragraph (f) or 
(h)(1) of this AD, prior to further flight, repair in accordance 
with paragraph (h)(1)(i) or (h)(1)(ii) of this AD, as applicable.
    (i) For Group 1 airplanes: Using a method approved in accordance 
with the procedures specified in paragraph (j) of this AD. The 
Boeing 747 Structural Repair Manual, Subject 53-10-04, Figure 67 or 
90, is one approved method.
    (ii) For Group 2 airplanes: Using a method approved in 
accordance with the procedures specified in paragraph (j) of this 
AD. The Boeing 747-400 Structural Repair Manual, Subject 53-60-07, 
Repair 1 or 2, is one approved method.
    (2) Repeat the inspection required by paragraph (f) of this AD 
thereafter at intervals not to exceed 3,000 flight cycles.

Optional Terminating Inspection

    (i) Accomplishment of the initial detailed inspection of the 
Section 46 lower lobe frames required by paragraph (f)(2) or (i)(2) 
of AD 2005-20-30 constitutes terminating action for the requirements 
of this AD only for airplanes identified in Boeing Alert Service 
Bulletin 747-53A2408, Revision 1, dated April 4, 2002, as Group 1 
airplanes. Accomplishment of the initial detailed inspection of the 
Section 46 lower lobe frames required by paragraph (f) of AD 2006-
05-02 constitutes terminating action for the requirements of this AD 
only for airplanes identified in Boeing Alert Service Bulletin 747-
53A2408, Revision 1, dated April 4, 2002, as Group 2 airplanes.

Alternative Methods of Compliance (AMOCs)

    (j)(1) The Manager, Seattle Aircraft Certification Office (ACO), 
FAA, has the authority to approve AMOCs for this AD, if requested in 
accordance with the procedures found in 14 CFR 39.19.
    (2) Before using any AMOC approved in accordance with Sec.  
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair required by this AD, if it is approved by an 
Authorized Representative for the Boeing Commercial Airplanes 
Delegation Option Authorization Organization who has been authorized 
by the Manager, Seattle ACO, to make those findings. For a repair 
method to be approved, the repair must meet the certification basis 
of the airplane.
    (4) AMOCs approved previously in accordance with AD 99-07-12, 
amendment

[[Page 39603]]

39-11097, are approved as AMOCs for the corresponding provisions of 
this AD.

    Issued in Renton, Washington, on July 5, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E6-11019 Filed 7-12-06; 8:45 am]
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