
[Federal Register: October 17, 2008 (Volume 73, Number 202)]
[Proposed Rules]               
[Page 61747-61749]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr17oc08-18]                         

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Proposed Rules
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains notices to the public of 
the proposed issuance of rules and regulations. The purpose of these 
notices is to give interested persons an opportunity to participate in 
the rule making prior to the adoption of the final rules.

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[[Page 61747]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-1103; Directorate Identifier 2008-NM-048-AD]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 727-100 and 727-200 Series 
Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for 
certain Boeing Model 727-100 and 727-200 series airplanes. This 
proposed AD would require repetitive internal and external high 
frequency eddy current, mid frequency eddy current, low frequency eddy 
current, and magneto optic imaging inspections to detect cracks, 
corrosion, delamination, and materials loss in the lower fastener row 
of the lower skin and the upper fastener row of the upper skin, and 
corrective actions if necessary. This proposed AD results from a report 
of decompression in a Boeing Model 737 airplane at flight level 290. We 
are proposing this AD to detect and correct scratches and excessive 
reduction in material thickness from excessive blend-out or corrosion, 
which could lead to premature cracking in the lap joint. Such cracking 
could adversely affect the structural integrity of the airplane.

DATES: We must receive comments on this proposed AD by December 1, 
2008.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://
www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this AD, contact Boeing 
Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (telephone 800-647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Berhane Alazar, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 
917-6577; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2008-1103; 
Directorate Identifier 2008-NM-048-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://
www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We received a report of decompression in a Boeing Model 737 
airplane at flight level (FL) 290. An investigation revealed that the 
skin flapped between stringer (S)-4R and S-5R from body station (BS) 
300 to BS 328. Examination of the skin showed cracks initiating at 
scratches in the lower skin of a lap joint that was cold-bonded in 
production. The lap splice had been separated for rework. These 
conditions, if not corrected, may result in scratches and excessive 
reduction in material thickness from excessive blend out or corrosion, 
which could lead to premature cracking in the lap joint. Such cracking 
could adversely affect the structural integrity of the airplane.
    The cold-bonded lap joints on certain Boeing Model 727 airplanes 
are similar to those on the affected Model 737 and Model 747 airplanes. 
Therefore, all of these models may be subject to the same unsafe 
condition.

Other Relevant Rulemaking

    On November 7, 2003, we issued AD 2003-23-03, amendment 39-13367 
(68 FR 64980, dated November 18, 2003), for 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 circumferential joint, and repair if necessary. 
That AD requires a terminating modification for the repetitive 
inspections.
    On June 9, 2004, we issued AD 2004-13-02, amendment 39-13682 (69 FR 
35237, June 24, 2004), for certain Boeing Model 747-100, -200B, and -
200F series airplanes. That AD requires initial and repetitive 
inspections to find discrepancies in the upper and lower skins of the 
fuselage lap joints, and repair if necessary.

Relevant Service Information

    We have reviewed Boeing Alert Service Bulletin 727-53A0223, dated 
March 28, 2002. The service bulletin describes procedures for 
repetitive internal and external high frequency eddy current (HFEC), 
mid frequency eddy current (MFEC), low frequency eddy current (LFEC), 
and magneto optic imaging (MOI) inspections to detect cracks, 
corrosion, delamination, and materials loss in the lower fastener row 
of the lower skin and the upper fastener

[[Page 61748]]

row of the upper skin, and corrective actions if necessary. The 
corrective actions include repairing all cracks; repairing skin 
material loss that is greater than 10%; separating, cleaning, and 
refastening corroded areas where skin loss is less than 10%; and 
replacing remaining fasteners with serviceable fasteners, if necessary.
    The service bulletin also specifies compliance times for initial 
HFEC, MFEC, LFEC, and MOI inspections ranging between 9 months or 1,500 
flight cycles, whichever is earlier, and 60 months or 7,500 flight 
cycles, whichever is earlier, depending on number of flight cycles on 
the airplane. The service bulletin also specifies repetitive intervals 
for HFEC, MFEC, LFEC, and MOI inspections every 2,000 or 7,000 flight 
cycles, or every 4 years, depending on inspection area and type.

FAA's Determination and Requirements of This Proposed AD

    We are proposing this AD because we evaluated all relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design. 
This proposed AD would require accomplishing the actions specified in 
the service information described previously, except as discussed under 
``Differences Between the Proposed Rule and Referenced Service 
Bulletin.''

Differences Between the Proposed Rule and Referenced Service Bulletin

    Operators should note that, although the Accomplishment 
Instructions of Boeing Alert Service Bulletin 727-53A0223, dated March 
28, 2002, describes procedures for reporting all cracks and evidence of 
corrosion to Boeing, this proposed AD would not require that action.

Costs of Compliance

    We estimate that this proposed AD would affect 73 airplanes of U.S. 
registry. We also estimate that it would take about 56 work hours per 
product to comply with this proposed AD. The average labor rate is $80 
per work hour. Based on these figures, we estimate the cost of this 
proposed AD to the U.S. operators to be $327,040, or $4,480 per 
product, 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 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 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 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. 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.
    You can find our regulatory evaluation and the estimated costs of 
compliance in the AD Docket.

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 FAA amends Sec.  39.13 by adding the following new AD:

Boeing: Docket No. FAA-2008-1103; Directorate Identifier 2008-NM-
048-AD.

Comments Due Date

    (a) We must receive comments by December 1, 2008.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 727-100 and 727-200 series 
airplanes, certificated in any category; as identified in Boeing 
Alert Service Bulletin 727-53A0223, dated March 28, 2002.

Unsafe Condition

    (d) This proposed AD results from a report of decompression in a 
Boeing Model 737 airplane at flight level 290. We are proposing this 
AD to detect and correct scratches and excessive reduction in 
material thickness from excessive blend-out or corrosion, which 
could lead to premature cracking in the lap joint. Such cracking 
could adversely affect the structural integrity of the airplane.

Compliance

    (e) Comply with this AD within the compliance times specified, 
unless already done.

Inspections and Corrective Actions

    (f) Except as provided by paragraphs (f)(1), (f)(2), and 
(f)(3)of this AD, at the applicable compliance times and repeat 
intervals listed in paragraph 1.E., ``Compliance,'' of Boeing Alert 
Service Bulletin 727-53A0223, dated March 28, 2002: Do repetitive 
internal and external high frequency eddy current, mid frequency 
eddy current, low frequency eddy current, and magneto optic imaging 
inspections to detect cracks, corrosion, delamination, and materials 
loss in the lower fastener row of the lower skin and the upper 
fastener row of the upper skin, and corrective actions by 
accomplishing all the applicable actions specified in the 
Accomplishment Instructions of the service bulletin. The applicable 
corrective actions must be done before further flight.
    (1) Where paragraph 1.E., ``Compliance,'' of the service 
bulletin identifies airplanes, ``Airplane Fight Cycles (f/c) at time 
of SB Release,'' this AD affects those airplanes with the specified 
flight cycles as of the effective date of this AD.
    (2) Where paragraph 1.E., ``Compliance,'' of the service 
bulletin specifies ``Initial Inspection Threshold From SB Rel Upper 
and Lower Skin,'' the AD requires compliance within the specified 
compliance times after the effective date of this AD.
    (3) Where paragraph 1.E., ``Compliance,'' of the service 
bulletin specifies ``Repeat every * * *,'' this AD requires 
compliance at intervals not to exceed the specified flight cycles or 
years.

No Reporting

    (g) Although Boeing Alert Service Bulletin 727-53A0223, dated 
March 28, 2002, specifies to submit information to the manufacturer, 
this AD does not include that requirement.

[[Page 61749]]

Alternative Methods of Compliance (AMOCs)

    (h)(1) The Manager, Seattle Aircraft Certification Office, FAA, 
ATTN: Berhane Alazar, Aerospace Engineer, Airframe Branch, ANM-120S, 
FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., 
Renton, Washington 98057-3356; telephone (425) 917-6577; fax (425) 
917-6590; has the authority to approve AMOCs for this AD, if 
requested using the procedures found in 14 CFR 39.19.
    (2) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your appropriate principal inspector (PI) in the FAA 
Flight Standards District Office (FSDO), or lacking a PI, your local 
FSDO.
    (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, and the approval must specifically refer to this 
AD.

    Issued in Renton, Washington, on September 29, 2008.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E8-24763 Filed 10-16-08; 8:45 am]

BILLING CODE 4910-13-P
