[Federal Register Volume 72, Number 152 (Wednesday, August 8, 2007)]
[Proposed Rules]
[Pages 44433-44435]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-15426]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-28884; Directorate Identifier 2007-NM-116-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 727 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 adopt a new airworthiness directive (AD) 
for all Boeing Model 727 airplanes. This proposed AD would require 
repetitive external high frequency eddy current (HFEC) inspections of 
the crown skin for cracks at certain stringer attachment holes, and 
repair if necessary. This proposed AD results from a report of cracks 
at multiple locations on certain areas of the crown skin. We are 
proposing this AD to detect and correct fatigue cracks of the crown 
skin, which could result in rapid decompression of the airplane.

DATES: We must receive comments on this proposed AD by September 24, 
2007.

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: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     Fax: (202) 493-2251.
     Hand Delivery: Room W12-140 on the ground floor of the 
West Building, 1200 New Jersey Avenue, SE., 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 the service information identified in this 
proposed AD.

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 submit any relevant written data, views, or 
arguments regarding this proposed AD. Send your comments to an address 
listed in the ADDRESSES section. Include the docket number ``FAA-2007-
28884; Directorate Identifier 2007-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 any of our 
dockets, 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 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 Operations office between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays. The 
Docket Operations office (telephone (800) 647-5527) is located on the

[[Page 44434]]

ground level of the West 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

    We have received a report indicating that fatigue tests resulted in 
cracks at multiple locations on the 727 body section 43 and 46 crown 
skin between stringers 11L and 11R. The first fatigue test cracks were 
found at approximately 66,000 simulated flight cycles. Subsequent 
inspection by Boeing on in-service airplanes also revealed similar 
crown skin cracks. In-service cracks were found on airplanes with 
between 71,236 and 81,234 total flight cycles. Fatigue cracks of the 
crown skin, if not detected and corrected, could result in rapid 
decompression of the airplane.

Relevant Service Information

    We have reviewed Boeing Alert Service Bulletin 727-53A0224, dated 
April 10, 2003. The service information describes procedures for 
repetitive external high frequency eddy current (HFEC) inspections of 
the crown skin for cracks at stringer attachment holes between stringer 
11L and stringer 11R and from body station (BS) 259.5 to BS 1183, and 
repair of any crack. Accomplishing the actions specified in the service 
information is intended to adequately address the unsafe condition.

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 require accomplishing the actions specified in the service 
information described previously, except as discussed under 
``Differences Between the Proposed AD and Referenced Service 
Information.''

Difference Between Proposed AD and Referenced Service Information

    Operators should note that, although the Accomplishment 
Instructions of the referenced service information describe procedures 
for reporting all cracks to Boeing, this proposed AD would not require 
that action.

Costs of Compliance

    There are about 842 airplanes of the affected design in the 
worldwide fleet. This proposed AD would affect about 459 airplanes of 
U.S. registry. The proposed inspection would take about 110 work hours 
per airplane, at an average labor rate of $80 per work hour. Based on 
these figures, the estimated cost of the proposed AD for U.S. operators 
is $4,039,200, or $8,800 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 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 placed 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 
adding the following new airworthiness directive (AD):

BOEING: Docket No. FAA-2007-28884; Directorate Identifier 2007-NM-
116-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by September 
24, 2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to all Boeing Model 727, 727C, 727-100, 727-
100C, 727-200, and 727-200F series airplanes, certificated in any 
category.

Unsafe Condition

    (d) This AD results from a report of cracks at multiple 
locations on certain areas of the crown skin. We are issuing this AD 
to detect and correct fatigue cracks of the crown skin, which could 
result in 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.

Repetitive Inspections and Repair

    (f) Before the accumulation of 66,000 total flight cycles, or 
within 3,500 flight cycles after the effective date of this AD, 
whichever occurs later, do an external high frequency eddy current 
inspection of the crown skin for cracks at stringer attachment holes 
between stringer 11L and stringer 11R and from body station (BS) 
259.5 to BS 1183. Repair any crack found before further flight. Do 
the actions in accordance with the Accomplishment Instructions of 
Boeing Alert Service Bulletin 727-53A0224, dated April 10, 2003, 
except as provided by paragraph (g) of this AD. Repeat the 
inspection at intervals not to exceed 3,500 flight cycles.
    (g) Although the service bulletin referred to in this AD 
specifies to submit certain information to the manufacturer, this AD 
does not include that requirement.

Alternative Methods of Compliance (AMOCs)

    (h)(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) To request a different method of compliance or a different 
compliance time

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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.

    Issued in Renton, Washington, on July 30, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E7-15426 Filed 8-7-07; 8:45 am]
BILLING CODE 4910-13-P