[Federal Register Volume 73, Number 59 (Wednesday, March 26, 2008)]
[Proposed Rules]
[Pages 15959-15961]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E8-6106]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2008-0357; Directorate Identifier 2008-NM-005-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-300, -400, and -500
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 all
Boeing Model 737-300, -400, and -500 series airplanes. This proposed AD
would require repetitive inspections for discrepancies of the fuse pins
of the inboard and outboard midspar fittings of the nacelle strut, and
corrective actions if necessary. This proposed AD results from a report
of corrosion damage of the chrome runout on the head side found on all
four midspar fuse pins of the nacelle strut. Additionally, a large
portion of the chrome plate was missing from the corroded area of the
shank. We are proposing this AD to detect and correct discrepancies of
the fuse pins of the inboard and outboard midspar fittings of the
nacelle strut, which could result in reduced structural integrity of
the fuse pins and consequent loss of the strut and separation of the
engine from the airplane.
DATES: We must receive comments on this proposed AD by May 12, 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: Allen Rauschendorfer, Aerospace
Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft
Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-
3356; telephone (425) 917-6432; 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-2008-0357;
Directorate Identifier 2008-NM-005-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 a report of corrosion damage of the chrome runout
on the head side found on all four midspar fuse pins of the nacelle
strut on a Model 737-300 airplane. Additionally, a large portion of the
chrome plate was missing from the corroded area of the shank. The
airplane had a total of 28,621 flight cycles. This condition, if not
corrected, could result in discrepancies of the fuse pins of the
inboard and outboard midspar fittings of the nacelle strut, reduced
structural integrity of the fuse pins, and consequent loss of the strut
and separation of the engine from the airplane.
Relevant Service Information
We have reviewed Boeing Special Attention Service Bulletin 737-54-
1044, dated December 10, 2007. The service bulletin describes
procedures for
[[Page 15960]]
repetitive detailed inspections for discrepancies (cracking, pitting,
corrosion, or chrome plate damage) of the fuse pins of the left- and
right-side inboard and outboard midspar fittings of the nacelle strut,
and corrective actions if necessary. The corrective actions include
blending out pitting or corrosion damage, inspecting blended areas to
make sure all damage was removed, and repairing or replacing damaged
fuse pins with new or serviceable fuse pins.
The compliance time specified in the service bulletin is the latest
of the following: Within 180 months from the date of issuance of the
original standard certificate of airworthiness or original export
certificate of airworthiness, within 180 months from date of previous
pin replacement, or within 24 months after the effective date of the
service bulletin. The repetitive interval is not to exceed 60 months.
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.
Interim Action
We consider this proposed AD interim action. The manufacturer is
currently developing a modification that will address the unsafe
condition identified in this AD. Once this modification is developed,
approved, and available, we might consider additional rulemaking.
Costs of Compliance
We estimate that this proposed AD would affect 616 airplanes of
U.S. registry. We also estimate that it would take about 4 work-hours
per product to comply with the inspection in 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
$197,120, or $320 per product.
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-2008-0357; Directorate Identifier 2008-NM-
005-AD.
Comments Due Date
(a) We must receive comments by May 12, 2008.
Affected ADs
(b) None.
Applicability
(c) This AD applies to all Boeing Model 737-300, -400, and -500
series airplanes, certificated in any category.
Unsafe Condition
(d) This AD results from a report of corrosion damage of the
chrome runout on the head side found on all four midspar fuse pins
of the nacelle strut. Additionally, a large portion of the chrome
plate was missing from the corroded area of the shank. We are
issuing this AD to detect and correct damage of the fuse pins of the
inboard and outboard midspar fittings of the nacelle strut, which
could result in reduced structural integrity of the fuse pins and
consequent loss of the strut and separation of the engine from the
airplane.
Compliance
(e) Comply with this AD within the compliance times specified,
unless already done.
Repetitive Inspections/Corrective Actions
(f) At the applicable time specified in paragraph 1.E.,
``Compliance'' of Boeing Special Attention Service Bulletin 737-54-
1044, dated December 10, 2007; except, where the service bulletin
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: Do a detailed inspection for
discrepancies of the fuse pins of the inboard and outboard midspar
fittings of the nacelle strut by doing all the actions, including
all applicable corrective actions, in accordance with the
Accomplishment Instructions of the service bulletin. Do all
applicable corrective actions before further flight. Repeat the
inspection at the time specified in paragraph 1.E. of the service
bulletin.
Alternative Methods of Compliance (AMOCs)
(g)(1) The Manager, Seattle Aircraft Certification Office (ACO),
FAA, ATTN: Allen Rauschendorfer, Aerospace Engineer, Airframe
Branch, ANM-120S, FAA, Seattle ACO, 1601 Lind Avenue, SW., Renton,
Washington 98057-3356; telephone (425) 917-6432; 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
[[Page 15961]]
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.
Issued in Renton, Washington, on March 19, 2008.
Dionne Palermo,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E8-6106 Filed 3-25-08; 8:45 am]
BILLING CODE 4910-13-P