[Federal Register: October 21, 2005 (Volume 70, Number 203)]
[Rules and Regulations]
[Page 61226-61229]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr21oc05-6]
=======================================================================
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2005-21086; Directorate Identifier 2004-NM-217-AD;
Amendment 39-14344; AD 2005-21-06]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-600, -700, -700C, -
800, and -900 Series Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule.
-----------------------------------------------------------------------
[[Page 61227]]
SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all
Boeing Model 737-600, -700, -700C, -800, and -900 series airplanes.
This AD requires repetitive inspections of the aft pressure bulkhead
web for fatigue cracks, crack indications, discrepant holes, and
corrosion; and repair if necessary. This AD results from reports of
fatigue cracks in the aft pressure bulkhead web. We are issuing this AD
to detect and correct such fatigue cracks, which could result in a
rapid decompression of the airplane.
DATES: This AD becomes effective November 25, 2005.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in the AD as of November 25,
2005.
ADDRESSES: You may examine the AD docket on the Internet at http://dms.dot.gov
or in person at the Docket Management Facility, U.S.
Department of Transportation, 400 Seventh Street, SW., Nassif Building,
room PL-401, Washington, DC.
Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle,
Washington 98124-2207, for service information identified in this AD.
FOR FURTHER INFORMATION CONTACT: Howard Hall, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425)
917-6430; fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
Examining the Docket
You may examine the airworthiness directive (AD) docket on the
Internet at http://dms.dot.gov or in person at the Docket Management
Facility office between 9 a.m. and 5 p.m., Monday through Friday,
except Federal holidays. The Docket Management Facility office
(telephone (800) 647-5227) is located on the plaza level of the Nassif
Building at the street address stated in the ADDRESSES section.
Discussion
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 to include an AD that would apply to all Boeing Model 737-
600, -700, -700C, -800, and -900 series airplanes. That NPRM was
published in the Federal Register on May 2, 2005 (70 FR 22620). That
NPRM proposed to require repetitive inspections of the aft pressure
bulkhead web for fatigue cracks, crack indications, discrepant holes,
and corrosion; and repair if necessary.
Comments
We provided the public the opportunity to participate in the
development of this AD. We have considered the comments received.
Supportive Comments
Two commenters, including the manufacturer, support the proposed
AD.
Request To Add Provision for Special Flight Permits
One commenter requests that the proposed AD be revised to include a
phrase used in earlier ADs to permit the use of special flight permits.
The commenter explains that, due to the number of work hours needed to
gain access to the forward side of the aft pressure bulkhead, it needs
to use the provisions for special flight permits. We infer that the
commenter believes that because the proposed AD does not contain
information on ferry flights, ferry flights are not allowed.
We do not agree with the commenter's request to add the special
flight permit language, nor do we agree with the commenter's inference
that special flight permits are not allowed by this AD. Special flight
permits are allowed unless limitations or prohibitions are specifically
identified in the AD. For this AD there are no limitations or
prohibitions. On July 10, 2002, we 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 (i.e., ferry flights), and
alternative methods of compliance (AMOCs). Since we have now included
this information in 14 CFR part 39, information on special flight
permits is not included in each individual AD unless there are
limitations on special flight permits for an individual AD. We have not
changed the AD in this regard.
Request To Add Language That Advises Operators How To Address Pre-
existing Repairs
Another commenter requests that the proposed AD be revised to
include language advising operators how to treat pre-existing repairs
in the inspection area of the aft pressure bulkhead. The commenter
justifies the request by noting that the ``* * * bulkhead is the
subject of numerous other service bulletins and other ADs, any or all
of which may have resulted in the installation of repairs in the
inspection area,'' and that the absence of such advisory language would
require AMOCs for each instance of pre-existing repairs. We infer that
the commenter believes that the AD requires AMOCs for each pre-existing
repair that prevents someone from complying with the requirements of
the AD, and is requesting that the AD include specific language to
provide relief for treating these pre-existing repairs.
We understand the commenter's concern about obtaining AMOCs for
pre-existing repairs, especially since there are three ADs that cover
the inspection area. We concur with the commenter in this regard. As
noted in the reply to the previous comment on special flight permits,
we issued a new version of 14 CFR part 39 on July 10, 2002. In section
39.17, it states, ``If a change in a product affects your ability to
accomplish the actions required by the airworthiness directive in any
way, you must request FAA approval of an alternative method of
compliance.'' This statement means that pre-existing repairs do not
require AMOC approval unless they affect the operator's ability to
accomplish the actions of the AD. Since we cannot anticipate the wide
variety of possible repair configurations, this is best handled by
requesting an AMOC for each repair. We have not changed the AD in this
regard.
Request To Query Boeing for Availability of Parts
One commenter notes that certain repairs would require replacement
of sections of curved structural members that are difficult for
operators to fabricate on short notice. The commenter suggests that
Boeing should be queried for availability of replacement materials in
the event that an inspection finds the need for corrective action.
We agree that certain parts may be difficult for operators to
fabricate on short notice (i.e., before further flight). We contacted
Boeing about parts availability in regard to this AD, and have
confirmed that a sufficient quantity of parts is available. We
encourage operators to contact Boeing for specific information on parts
availability. We have not changed the AD in this regard.
Request to Operator for Additional Repair Guidance
One commenter requests that Boeing provide additional repair
guidance other than ``contact Boeing.'' The commenter notes that the
manufacturer has previous experience in addressing similar repairs in
the area to be inspected in accordance with this AD. The commenter
acknowledges that every repair is different, but believes that a repair
drawing or structural-repair-manual-type of repair should be
[[Page 61228]]
made available. The commenter also states that it is impractical to
contact Boeing in an airline's operational environment.
We acknowledge the commenter's request. We understand that general
repair information applicable to this AD would help operators plan for
any potential corrective action. We have coordinated this issue with
Boeing. However, in this particular area, it is difficult to develop
specific guidelines for the various conditions that an operator may
encounter. Although no general repair information exists now (at time
of publication), we remind operators that we may approve (if submitted
and approved) repair drawings as allowed for in paragraph (i) of this
AD, which describes ways to get approval of an alternative method of
compliance (AMOC). We remind operators that they may apply for an AMOC
in accordance with the provisions in paragraphs (i) and (g) of this AD.
We have not changed the AD in this regard.
Conclusion
We have carefully reviewed the available data, including the
comments received, and determined that air safety and the public
interest require adopting the AD as proposed.
Explanation of Change Made to This AD
We have simplified paragraph (g) of this AD by referring to the
``Alternative Methods of Compliance (AMOCs)'' paragraph of this AD for
repair methods.
Clarification of Alternative Method of Compliance (AMOC) Paragraph
We have revised this AD to clarify the appropriate procedure for
notifying the principal inspector before using any approved AMOC on any
airplane to which the AMOC applies.
Costs of Compliance
There are about 978 airplanes of the affected design in the
worldwide fleet. The following table provides the estimated costs for
U.S. operators to comply with this AD:
Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
Number of
Work Average U.S.-
Action hours labor rate Parts Cost per airplane registered Fleet cost
per hour airplanes
--------------------------------------------------------------------------------------------------------------------------------------------------------
LFEC and detailed inspection, 8 $65 None..... $520 per inspection cycle........ 630 $327,600 per inspection cycle.
per inspection cycle.
HFEC and detailed inspection 2 65 None..... $130 per inspection cycle........ 630 $81,900 per inspection cycle.
(in lieu of LFEC and
detailed inspection), 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 AD will not have federalism
implications under Executive Order 13132. This AD will 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 this AD:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866;
(2) Is not a ``significant rule'' under 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 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, Incorporation by
reference, Safety.
Adoption of the Amendment
0
Accordingly, under the authority delegated to me by the Administrator,
the FAA amends 14 CFR part 39 as follows:
PART 39--AIRWORTHINESS DIRECTIVES
0
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]
0
2. The Federal Aviation Administration (FAA) amends Sec. 39.13 by
adding the following new airworthiness directive (AD):
2005-21-06 Boeing: Amendment 39-14344. Docket No. FAA-2005-21086;
Directorate Identifier 2004-NM-217-AD.
Effective Date
(a) This AD becomes effective November 25, 2005.
Affected ADs
(b) None.
Applicability
(c) This AD applies to all Boeing Model 737-600, -700, -700C, -
800, and -900 series airplanes, certificated in any category.
Unsafe Condition
(d) This AD was prompted by reports of fatigue cracks in the aft
pressure bulkhead web. We are issuing this AD to detect and correct
such fatigue cracks, which could result in rapid decompression of
the airplane.
[[Page 61229]]
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
(f) At the applicable ``Inspection Threshold'' in the table in
Part 1.E. ``Compliance'' of Boeing Alert Service Bulletin 737-
53A1248, dated September 9, 2004, or within 18 months after the
effective date of this AD, whichever occurs later, and thereafter at
intervals not to exceed the applicable ``Inspection Repeat
Interval'' in that table: Do the inspections (i.e., detailed
inspection and either high- or low-frequency eddy current
inspections) of the aft pressure bulkhead web for fatigue cracks,
crack indications, discrepant holes, and corrosion, in accordance
with the Accomplishment Instructions of the service bulletin.
Corrective Action Difference
(g) If any fatigue crack, crack indication, discrepant hole, or
corrosion is found during any inspection required by this AD, before
further flight, repair the fatigue crack, crack indication,
discrepant hole, and corrosion according to a method approved by the
Manager, Seattle Aircraft Certification Office (ACO), FAA; or using
a method approved in accordance with the procedures specified in
paragraph (i) of this AD.
No Reporting
(h) Although the service bulletin references a reporting
requirement in the Accomplishment Instructions, that reporting is
not required by this AD.
Alternative Methods of Compliance (AMOCs)
(i)(1) The Manager, Seattle 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) An AMOC that provides an acceptable level of safety may be
used for corrective actions, 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.
(3) Before using any AMOC approved in accordance with Sec.
39.19 on any airplane to which the AMOC applies, notify the
appropriate principal inspector in the FAA Flight Standards
Certificate Holding District Office.
Material Incorporated by Reference
(j) You must use Boeing Alert Service Bulletin 737-53A1248,
dated September 9, 2004, to perform the actions that are required by
this AD, unless the AD specifies otherwise. The Director of the
Federal Register approved the incorporation by reference of this
document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51.
Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle,
Washington 98124-2207, for a copy of this service information. You
may review copies at the Docket Management Facility, U.S. Department
of Transportation, 400 Seventh Street, SW., room PL-401, Nassif
Building, Washington, DC; on the Internet at http://dms.dot.gov; or
at the National Archives and Records Administration (NARA). For
information on the availability of this material at the NARA, call
(202) 741-6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html
.
Issued in Renton, Washington, on October 13, 2005.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 05-20966 Filed 10-20-05; 8:45 am]
BILLING CODE 4910-13-P