[Federal Register Volume 72, Number 226 (Monday, November 26, 2007)]
[Proposed Rules]
[Pages 65913-65916]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-22939]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-0227; Directorate Identifier 2007-NM-159-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 inspections for cracking or corrosion of the threaded end of 
the lower segment of the main landing gear (MLG) side strut, and 
corrective actions if necessary. This proposed AD also would require 
prior or concurrent inspection for cracking or corrosion of the threads 
and thread relief area of the lower segment, corrective action if 
necessary, and re-assembly using corrosion inhibiting compound. This 
proposed AD results from reports of the threads cracking on the MLG 
side strut lower segment. We are proposing this AD to prevent a 
fractured side strut, which could result in collapse of the MLG.

DATES: We must receive comments on this proposed AD by January 10, 
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,

[[Page 65914]]

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-2007-0227; 
Directorate Identifier 2007-NM-159-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 have received many reports of the threads cracking on the main 
landing gear (MLG) side strut lower segment, on Boeing Model 727 
airplanes. In one instance an operator reported hearing a loud noise 
during taxiing after landing. The subsequent inspection revealed the 
MLG side strut was broken at the threaded end of the lower segment, 
causing the side strut to become detached from the shock strut. This 
condition, if not corrected, could result in collapse of the MLG.

Relevant Service Information

    We have reviewed Boeing Special Attention Service Bulletin 727-32-
0338, Revision 4, dated April 7, 2007. The service bulletin describes 
procedures for repetitive detailed and magnetic particle inspections 
for cracking or corrosion of the threaded end of the lower segment of 
the MLG side strut. The service bulletin also describes procedures for 
corrective actions for corrosion or cracking. The corrective actions 
include replacing the part with a serviceable part, repairing the part 
as given in the Boeing Model 727 Overhaul Manual (OHM) 32-13-01, and 
doing a modification of the lower segment. There are five 
configurations for modification:
     Option I Configuration--Blending out cracks and doing 
thread root radiusing. This modification applies only to airplanes with 
maximum taxi gross weight of 191,000 pounds and below.
     Option II Configuration--Installing a new retainer nut, 
locknut, lock washer, and seals. This modification applies only to 
airplanes on which the segment is crack-free.
     Option III Configuration--Removing 0.8-inch of the lower 
end of the lower segment, inserting a spacer, and replacing the 
retainer nut, locknut, lock washer, and seals.
     Option IV Configuration--Similar to Option III, but also 
removing additional lubrication on the retainer nut; and applying 
corrosion inhibiting compound, rather than grease, to the threads at 
re-assembly.
     Option V Configuration--Replacing the side strut lower 
segment with a larger-diameter spare (not production) part that has 
fatigue improvement on the threads.
    Boeing Special Attention Service Bulletin 727-32-0338, Revision 4, 
also recommends the prior or concurrent accomplishment of the actions 
specified in the table titled ``Prior/Concurrent Service Bulletins.'' 
The prior/concurrent service bulletins facilitate the overhaul and 
repair procedures specified in Boeing Special Attention Service 
Bulletin 727-32-0338, Revision 4.

                   Prior/Concurrent Service Bulletins
------------------------------------------------------------------------
                                                    Describes procedures
                               Boeing 727 service    for these prior or
            For--                  bulletin--       concurrent actions--
 
------------------------------------------------------------------------
All airplanes...............  727-32-0411,          Inspecting for
                               Revision 1, dated     corrosion or
                               February 19, 2007.    cracking of the
                                                     threads and thread
                                                     relief area of the
                                                     swivel clevis, and
                                                     improving the
                                                     corrosion
                                                     protection of the
                                                     swivel clevis
                                                     fitting threads in
                                                     commonly affected
                                                     airplanes.
Airplanes specified as        32-79, Revision 1,    Modifying the MLG
 Options III, IV and V         dated February 27,    side strut
 configurations in Boeing      1967.                 universal joint.
 Special Attention Service
 Bulletin 727-32-0338,
 Revision 4.
                              32-157, dated August  Replacing the MLG
                               30, 1968.             side strut swivel
                                                     bushing,
                                                     incorporating only
                                                     Parts Kit 65-89855-
                                                     1, and not
                                                     installing the lube
                                                     fitting in the
                                                     lower segment.
Airplanes specified as        727-32-268, Revision  Inspecting and
 Option V configuration in     2, dated February     modifying the MLG
 Boeing Special Attention      20, 1981.             side strut.
 Service Bulletin 727-32-
 0338, Revision 4.
                              727-57-163, dated     Resolving the
                               September 17, 1982.   interference
                                                     between the MLG
                                                     gear beam and the
                                                     MLG side strut.
------------------------------------------------------------------------

    Boeing Special Attention Service Bulletin 727-32-0338, Revision 4, 
specifies that where any assembly, lubrication, or corrosion protection 
procedure in a prior/concurrent service bulletin differs from those in 
Boeing Special Attention Service Bulletin 727-32-0338, Revision 4, 
operators should use the procedures in Boeing Special Attention Service 
Bulletin 727-32-0338, Revision 4.
    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.

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 following table provides the estimated costs for 
U.S. operators to comply with

[[Page 65915]]

this proposed AD. The average labor rate is $80 per work hour.

                                                 Estimated Costs
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                                                     Average labor
              Action                  Work hours     rate per hour    Cost per airplane          Fleet cost
----------------------------------------------------------------------------------------------------------------
Inspection........................              12             $80  $960, per inspection   $440,640, per
                                                                     cycle.                 inspection cycle.
Prior/concurrent actions..........         Up to 6             $80  Up to $480...........  Up to $220,320.
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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-2007-0227; Directorate Identifier 2007-NM-
159-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by January 
10, 2008.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to all 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 reports of the threads cracking on the 
main landing gear (MLG) side strut lower segment. We are issuing 
this AD to prevent a fractured side strut, which could result in 
collapse of the MLG.

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.

Inspections and Corrective Actions

    (f) At the latest applicable time in paragraph (f)(1), (f)(2), 
or (f)(3) of this AD: Do detailed and magnetic particle inspections 
for cracking or corrosion of the threaded end of the lower segment 
of the MLG side strut and do all applicable corrective actions as 
specified in the Accomplishment Instructions of Boeing Special 
Attention Service Bulletin 727-32-0338, Revision 4, dated April 7, 
2007. Do all applicable corrective actions before further flight. 
Repeat the inspection thereafter at intervals not to exceed 120 
months.
    (1) Within 48 months after the last MLG overhaul.
    (2) Within 6 months after the effective date of this AD.
    (3) Within 120 months after the last MLG overhaul for airplanes 
on which the actions in Boeing Special Attention Service Bulletin 
727-32-0338, Revision 4, dated April 7, 2007, have been accomplished 
before the effective date of this AD.

Prior/Concurrent Requirements

    (g) Prior to or concurrently with the actions required by 
paragraph (f) of this AD: Do all applicable actions specified in the 
service bulletins listed in Table 1 of this AD. Where the 
lubrication and corrosion protection procedures in any service 
bulletin listed in Table 1 of this AD differ from those in Boeing 
Special Attention Service Bulletin 727-32-0338, Revision 4, dated 
April 7, 2007, use the procedures in Boeing Special Attention 
Service Bulletin 727-32-0338, Revision 4.

                 Table 1.--Prior/Concurrent Requirements
------------------------------------------------------------------------
                                                    Describes procedures
            For--              Boeing 727 service    for these prior or
                                   bulletin--       concurrent actions--
------------------------------------------------------------------------
(1) All airplanes...........  727-32-0411,          Inspecting for
                               Revision 1, dated     corrosion or
                               February 19, 2007.    cracking of the
                                                     threads and thread
                                                     relief area of the
                                                     swivel clevis, and
                                                     improving the
                                                     corrosion
                                                     protection of the
                                                     swivel clevis
                                                     fitting threads in
                                                     commonly affected
                                                     airplanes.

[[Page 65916]]

 
(2) Airplanes specified as    32-79, Revision 1,    Modifying the MLG
 Options III, IV and V         dated February 27,    side strut
 configurations in Boeing      1967.                 universal joint.
 Special Attention Service
 Bulletin 727-32-0338,
 Revision 4.
                              32-157, dated August  Replacing the MLG
                               30, 1968.             side strut swivel
                                                     bushing,
                                                     incorporating only
                                                     Parts Kit 65-89855-
                                                     1, and not
                                                     installing the lube
                                                     fitting in the
                                                     lower segment.
(3) Airplanes specified as    727-32-268, Revision  Inspecting and
 Option V configuration in     2, dated February     modifying the MLG
 Boeing Special Attention      20, 1981.             side strut.
 Service Bulletin 727-32-
 0338, Revision 4.
                              727-57-163, dated     Resolving the
                               September 17, 1982.   interference
                                                     between the MLG
                                                     gear beam and the
                                                     MLG side strut.
------------------------------------------------------------------------

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 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 November 13, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E7-22939 Filed 11-23-07; 8:45 am]
BILLING CODE 4910-13-P