[Federal Register Volume 68, Number 127 (Wednesday, July 2, 2003)]
[Proposed Rules]
[Pages 39483-39485]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-16694]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NM-149-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747-100, -200B, and -200F 
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 747-100, -
200B, and -200F series airplanes. This proposal would require initial 
and repetitive inspections to find discrepancies in the upper and lower 
skins of the fuselage lap joints, and repair if necessary. This action 
is necessary to find and fix such discrepancies, which could result in 
sudden fracture and failure of a lap joint and rapid in-flight 
decompression of the airplane fuselage. This action is intended to 
address the identified unsafe condition.

DATES: Comments must be received by August 18, 2003.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2002-NM-

[[Page 39484]]

149-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-149-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 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.

FOR FURTHER INFORMATION CONTACT: Rick Kawaguchi, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
917-6434; 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 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-149-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-149-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received a report indicating rapid in-flight 
decompression of a Boeing Model 737 series airplane. Investigation 
revealed that the skin above the forward entry door was separated at 
the stringer S-4R lap joint, with a 28-inch tear running along the lap 
joint. The skin was bent back at the upper edge of the stringer at S-5R 
and formed a rectangular opening that progressed from body station (BS) 
328 to BS 300. Further investigation revealed that numerous scratches 
on the skin of the lap joint had initiated fatigue cracks and 
subsequent tearing of the skin. We also have received reports of 
similar damage (corrosion and fatigue cracking) to certain lap joints 
on other Model 737 series airplanes. These discrepancies have been 
attributed to the manufacturing process, which includes a cold-bonded 
adhesive of the lap joint configuration. Such conditions, if not 
corrected, could result in sudden fracture and failure of a lap joint 
and rapid in-flight decompression of the airplane fuselage.
    The subject area on certain Model 747-100, -200B, and -200F series 
airplanes is manufactured using a process similar to that used on the 
affected Model 737 series airplanes. Therefore, those Model 747-100, -
200B, and -200F series airplanes may be subject to the same unsafe 
condition revealed on the Model 737 series airplanes.

Related AD

    This AD is related to AD 2000-17-04, amendment 39-11878, (65 FR 
51750, August 25, 2000), applicable to certain Boeing Model 737-100, -
200, and -200C series airplanes. That AD requires repetitive 
inspections to detect discrepancies in the upper and lower skins of the 
fuselage lap joint, and repair if necessary.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Alert Service Bulletin 
747-53A2463, including Appendices A, B, and C, and the Evaluation Form, 
dated March 7, 2002, which describes procedures for repetitive medium 
and low frequency eddy current inspections for discrepancies (cracking 
and/or corrosion), and repair of any discrepancies found. 
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.

Difference Between Alert Service Bulletin and This Proposed AD

    Although the alert service bulletin specifies that the manufacturer 
may be contacted for disposition of certain repair conditions or 
inspection procedures, this proposed AD requires the repair and 
inspection procedures be accomplished in accordance with a method 
approved by the FAA, 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 
FAA to make such findings.

Changes to 14 CFR Part 39/Effect on the Proposed AD

    On July 10, 2002, the FAA issued a new version of 14 CFR part 39 
(67 FR 47997, July 22, 2002), which governs the FAA's airworthiness 
directives system. The regulation now includes material that relates to 
altered products, special flight permits, and alternative methods of 
compliance. Because we have now included this material in part 39, we 
no longer need to include it in each individual AD; however, this AD 
identifies the office authorized to approve alternative methods of 
compliance.

Cost Impact

    There are approximately 86 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 55

[[Page 39485]]

airplanes of U.S. registry would be affected by this proposed AD, that 
it would take approximately 5,334 work hours per airplane to accomplish 
the proposed inspections, and that the average labor rate is $60 per 
work hour. Based on these figures, the cost impact of the proposed AD 
on U.S. operators is estimated to be $17,602,200, or $320,040 per 
airplane.
    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 
planning time, or time necessitated by other administrative actions.

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:

    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-149-AD.

    Applicability: Model 747-100, -200B, and -200F series airplanes, 
as listed in Boeing Alert Service Bulletin 747-53A2463, dated March 
7, 2002; certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To find and fix discrepancies in the upper and lower skins of 
the fuselage lap joints, which could result in sudden fracture and 
failure of a lap joint and rapid in-flight decompression of the 
airplane fuselage, accomplish the following:

Initial and Repetitive Inspections

    (a) Do the applicable (initial and repetitive) inspections as 
specified in Figures 2 through 8, as applicable, of the 
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
53A2463, including Appendices A, B, and C, dated March 7, 2002, to 
find discrepancies (cracking and corrosion) in the upper and lower 
skins of the fuselage lap joints. Do the inspections at the 
applicable times specified in Figure 1 of the Accomplishment 
Instructions of the alert service bulletin, in accordance with the 
alert service bulletin; except that where Figure 1 specifies a 
compliance time of ``after the release date of this service 
bulletin,'' this AD requires a compliance time of ``after the 
effective date of this AD.'' Where Figure 1 specifies a compliance 
time of ``flight cycles'' this AD requires a compliance time of 
``total flight cycles.''
    (b) Where Boeing Alert Service Bulletin 747-53A2463, including 
Appendices A, B, and C, dated March 7, 2002, specifies that the 
manufacturer may be contacted for certain inspection procedures, 
inspect 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 (DER) who has been authorized 
by the Manager, Seattle ACO, to make such findings.

Adjustments to Compliance Time: Cabin Differential Pressure

    (c) For the purposes of calculating the compliance threshold and 
repetitive interval for the inspections required by paragraph (a) of 
this AD: Flight cycles in which cabin differential pressure is at 
2.0 pounds per square inch (psi) or less need not be counted when 
determining the number of flight cycles that have occurred on the 
airplane, provided that flight cycles with momentary spikes in cabin 
differential pressure above 2.0 psi are included as full pressure 
flight cycles. For this provision to apply, all cabin pressure 
records must be maintained for each airplane. No fleet-averaging of 
cabin pressure is allowed.

Repair

    (d) Before further flight, repair any discrepancy (cracking or 
corrosion) found during any inspection required by paragraph (a) of 
this AD, per the Accomplishment Instructions of Boeing Alert Service 
Bulletin 747-53A2463, including Appendices A, B, and C, dated March 
7, 2002. If any discrepancy is found and the alert service bulletin 
specifies that the manufacturer may be contacted for disposition of 
certain repairs, before further flight, repair per a method approved 
by the Manager, Seattle ACO; 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.

Alternative Methods of Compliance

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

    Issued in Renton, Washington, on June 26, 2003.
Michael J. Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 03-16694 Filed 7-1-03; 8:45 am]
BILLING CODE 4910-13-P