
[Federal Register: October 29, 2008 (Volume 73, Number 210)]
[Proposed Rules]               
[Page 64284-64286]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr29oc08-25]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-1117; Directorate Identifier 2008-NM-106-AD]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 727 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 all 
Boeing Model 727 airplanes. This proposed AD would require inspections 
for cracking of the left- and right-side shear ties and web posts of 
the kickload beam and the adjacent structure in the vertical 
stabilizer, and corrective actions if necessary. This proposed AD 
results from a report of cracking of the left- and right-side web posts 
and shear ties of the kickload beam. We are proposing this AD to detect 
and correct cracking of the left- and right-side web posts and shear 
ties of the kickload beam, which, when coupled with failures in the 
adjacent structure, could result in structural failure of the vertical 
stabilizer, and loss of control of the airplane.

DATES: We must receive comments on this proposed AD by December 15, 
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-2008-1117; 
Directorate Identifier 2008-NM-106-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

[[Page 64285]]

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 have received a report of cracking of the left- and right-side 
web posts and shear ties of the kickload beam. The cracking was 
discovered during a scheduled maintenance visit of an airplane with 
65,000 total flight hours and 42,000 total flight cycles. The reported 
cracking of the left- and right-side web posts, which attach to the 
kickload beam and the left- and right-side stringer 11 in the vertical 
stabilizer, was due to stress corrosion caused by elevated fit up 
stress. Cracking in the left- and right-side shear ties, which attach 
to the kickload beam, was a result of fatigue caused by compensation 
for cracking in the web posts. Cracking of the shear ties and web posts 
can diminish the effectiveness of both left- and right-side stringer 
11. When coupled with failures in the rear spar chord or stringer 10, 
the critical crack length at which limit load can be sustained is 
reduced, rendering the existing inspection intervals for stringer 10 
and the rear spar chord insufficient. This condition, if not corrected, 
could result in structural failure of the vertical stabilizer, which 
could lead to loss of control of the airplane.

Relevant Service Information

    We have reviewed Boeing Special Attention Service Bulletin 727-55-
0093, dated March 12, 2008. The service bulletin describes procedures 
for doing repetitive high frequency eddy current (HFEC) and low 
frequency eddy current (LFEC) inspections for cracking of the left- and 
right-side shear ties, left- and right-side web posts, left- and right-
side stringers 10 and 11, rear spar chord, associated critical 
fasteners, and adjacent surfaces in the vertical stabilizer. For 
airplanes on which any cracking is found in the shear ties or web 
posts, the service bulletin describes replacing the cracked parts with 
new parts and inspecting all open fastener holes in the kickload beam 
web and chords for cracking. For airplanes on which cracking is found 
in stringer 10 or 11, rear spar chord and skin, associated critical 
fasteners, adjacent surfaces of the vertical stabilizer, or areas other 
than the shear ties and web posts, the service bulletin specifies 
contacting Boeing for repair instructions. The service bulletin 
specifies the following compliance times:

                                                Compliance Times
----------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------
Airplanes/condition                                     Compliance time                  Repetitive interval
                                                   (whichever occurs first)
----------------------------------------------------------------------------------------------------------------
Less than 52,000 total flight hours    Before 56,000 total      Before 42,000 total      10,000 flight hours or
 or 39,000 total flight cycles.         flight hours.            flight cycles.           7,500 flight cycles,
                                                                                          whichever occurs
                                                                                          first.
More than 52,000 total flight hours    Within 4,000 flight      Within 3,000 flight      10,000 flight hours or
 or 39,000 total flight cycles.         hours after the date     cycles after the date    7,500 flight cycles,
                                        of the service           of the service           whichever occurs
                                        bulletin.                bulletin.                first.
Any cracking found...................  Before further flight..  .......................  (None).
----------------------------------------------------------------------------------------------------------------

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(se) same type 
design(s). This proposed AD would require accomplishing the actions 
specified in the service information described previously, except as 
discussed under ``Differences Between the Proposed AD and the Service 
Bulletin.''

Differences Between the Proposed AD and the Service Bulletin

    Boeing Special Attention Service Bulletin 727-55-0093, dated March 
12, 2008, specifies to contact the manufacturer for instructions on how 
to repair certain conditions, but this proposed AD would require 
repairing those conditions in one of the following ways:
     Using a method that we approve; or
     Using data that meet the certification basis of the 
airplane, and that have been approved by an Authorized Representative 
for the Boeing Commercial Airplanes Delegation Option Authorization 
Organization, whom we have authorized to make those findings.
    The service bulletin does not specify a compliance time for 
airplanes with exactly 52,000 total flight hours or 39,000 total flight 
cycles. We have grouped those airplanes with airplanes having ``less 
than'' 52,000 total flight hours or 39,000 total flight cycles, as 
specified in paragraph (g) of this proposed AD.

Interim Action

    We consider this proposed AD interim action. If final action is 
later identified, we might consider further rulemaking then.

Costs of Compliance

    We estimate that this proposed AD would affect 364 airplanes of 
U.S. registry. The following table provides the estimated costs for 
U.S. operators to comply with this proposed AD.

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                            Average                                  Number of
                                   Work      labor                                     U.S.-
            Action                hours    rate  per    Parts    Cost per  product  registered     Fleet cost
                                              hour                                   airplanes
----------------------------------------------------------------------------------------------------------------
Inspection....................         10        $80         $0  $800, per                 364  $291,200, per
                                                                  inspection cycle.              inspection
                                                                                                 cycle.
----------------------------------------------------------------------------------------------------------------


[[Page 64286]]

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, Incorporation by 
reference, 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-2008-1117; Directorate Identifier 2008-NM-
106-AD.

Comments Due Date

    (a) We must receive comments by December 15, 2008.

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 cracking of the left- and 
right-side web posts and shear ties of the kickload beam. We are 
issuing this AD to detect and correct cracking of the left- and 
right-side web posts and shear ties of the kickload beam, which, 
when coupled with failures in the adjacent structure, could result 
in structural failure of the vertical stabilizer, and loss of 
control of the airplane.

Compliance

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

Inspections and Corrective Actions

    (f) At the times specified in paragraph 1.E., ``Compliance,'' of 
Boeing Special Attention Service Bulletin 727-55-0093, dated March 
12, 2008 (``the service bulletin''), except as provided by 
paragraphs (g) and (h) of this AD: Do the inspections to detect 
cracking of the left- and right-side web posts and shear ties of the 
kickload beam, by doing all of the actions specified in Part 2 and 
the applicable corrective actions specified in Part 3 of the 
Accomplishment Instructions of the service bulletin, except as 
provided by paragraph (i) of this AD. Do all applicable corrective 
actions before further flight. Repeat the inspections thereafter at 
the intervals specified in paragraph 1.E. of the service bulletin.

Clarification and Exception to the Specified Compliance Times

    (g) To determine the compliance times for airplanes having 
exactly 52,000 total flight hours or 39,000 total flight cycles, for 
the purposes of this AD, these airplanes are grouped with airplanes 
having ``less than'' 52,000 total flight hours or 39,000 total 
flight cycles, as specified in paragraph 1.E., ``Compliance,'' of 
Boeing Special Attention Service Bulletin 727-55-0093, dated March 
12, 2008.
    (h) Where Boeing Special Attention Service Bulletin 727-55-0093, 
dated March 12, 2008, specifies a compliance time after the date on 
the service bulletin, this AD requires compliance within the 
specified compliance time after the effective date of this AD.

Exception to the Specified Corrective Actions

    (i) If any cracking is found during any inspection required by 
this AD, and Boeing Special Attention Service Bulletin 727-55-0093, 
dated March 12, 2008, specifies contacting Boeing for appropriate 
action: Before further flight, repair the cracking or damage using a 
method approved by the Manager, Seattle Aircraft Certification 
Office (ACO), FAA. For a repair method to be approved by the 
Manager, Seattle ACO, as required by this paragraph, the Manager's 
approval letter must specifically refer to this AD.

Alternative Methods of Compliance (AMOCs)

    (j)(1) The Manager, Seattle ACO, FAA, ATTN: Berhane Alazar, 
Aerospace Engineer, Airframe Branch, ANM-120S, 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 October 10, 2008.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E8-25758 Filed 10-28-08; 8:45 am]

BILLING CODE 4910-13-P
