[Federal Register: March 3, 2005 (Volume 70, Number 41)]
[Proposed Rules]
[Page 10337-10339]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr03mr05-8]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2005-20475; Directorate Identifier 2004-NM-157-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 777-200, -200ER, and -300
Series 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 certain Boeing Model 777-200, -200ER, and -300 series airplanes.
This proposed AD would require modification of the splice plate
assemblies installed under the floor panels at the forward and aft
edges of the cabin aisle. This proposed AD is prompted by reports of
cracking of the aluminum splice plates under the floor panels in the
cabin aisle. We are proposing this AD to prevent loss of the capability
of the cabin floor and seat track structure to support the airplane
interior inertia loads under emergency landing conditions. Loss of this
support could lead to galley or seat separation from attached
restraints, which could result in blocking of the emergency exits and
consequent injury to passengers and crew.
DATES: We must receive comments on this proposed AD by April 18, 2005.
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: Docket Management Facility, U.S. Department of
Transportation, 400 Seventh Street, SW., Nassif Building, room PL-401,
Washington, DC 20590.
By fax: (202) 493-2251.
Hand Delivery: Room PL-401 on the plaza level of the
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
For service information identified in this proposed AD, contact
Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-
2207.
You can examine the contents of this 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., room PL-
401, on the plaza level of the Nassif Building, Washington, DC. This
docket number is FAA-2005-20475; the directorate identifier for this
docket is 2004-NM-157-AD.
FOR FURTHER INFORMATION CONTACT: Gary Oltman, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425)
917-6443; 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 under ADDRESSES. Include ``Docket No. FAA-2005-20475;
Directorate Identifier 2004-NM-157-AD'' in the subject line 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 submitted 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
[[Page 10338]]
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 can review DOT's
complete Privacy Act Statement in the Federal Register published on
April 11, 2000 (65 FR 19477-78), or you can visit http://dms.dot.gov.
Examining the Docket
You can examine the 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 DOT
street address stated in the ADDRESSES section. Comments will be
available in the AD docket shortly after the DMS receives them.
Discussion
We have received reports indicating that cracking of the aluminum
splice plates installed at the forward and aft edges under the floor
panels in the cabin was found during routine maintenance on several
Model 777 series airplanes. The floor panels are attached with
fasteners that pass through the floor panel and connect to a threaded
nut plate on the splice plate. The airplanes had accumulated between
1,375 and 14,614 total flight cycles. Analysis shows that the cracking
of the splice plates is due to repeated bending from frequent traffic
in the cabin aisle. This condition, if not corrected, could result in
loss of the capability of the cabin floor and seat track structure to
support the airplane interior inertia loads under emergency landing
conditions. Loss of this support could lead to galley or seat
separation from attached restraints, which could result in blocking of
the emergency exits and consequent injury to passengers and crew.
Relevant Service Information
We have reviewed Boeing Special Attention Service Bulletin 777-53-
0042, dated April 15, 2004. The service bulletin describes procedures
for modification of the splice plate assemblies under the floor panels
at the forward and aft edges of the cabin aisle. The modification
involves replacing the existing aluminum splice plate assemblies with
new fiberglass laminate assemblies; and marking the service bulletin
number on the top of the floor panel. The modification also includes
replacing any damaged fasteners with new fasteners. 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. Therefore, 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 Service Bulletin.''
Differences Between the Proposed AD and Service Bulletin
The service bulletin recommends accomplishing the modification at
the next scheduled heavy maintenance check, not to exceed 72 months
from the service bulletin release date. We have determined that,
because maintenance schedules vary among operators, and in order to
address the unsafe condition in a timely manner, this proposed AD would
require compliance within 60 months after the effective date of this
AD. In developing an appropriate compliance time for this proposed AD,
we considered not only the manufacturer's recommendation, but the
degree of urgency associated with addressing the subject unsafe
condition, the average utilization of the affected fleet, and the time
necessary to perform the modification. In light of all of these
factors, we find a compliance time of 60 months for completing the
modification to be warranted, in that it represents an appropriate
interval of time for affected airplanes to continue to operate without
compromising safety.
The applicability of the service bulletin inadvertently excluded
Boeing Model 777-200ER series airplanes. Therefore, this proposed AD
includes a requirement that the actions specified in the service
bulletin be accomplished on those airplanes. This requirement would
ensure that the actions specified in the service bulletin, and required
by this proposed AD, are accomplished on all affected airplanes.
The service bulletin also recommends marking the service bulletin
number on the top of the floor panel assembly, but this proposed AD
would not require that action. We find that, with a variety of marking
methods and panel locations, this marking could not be accurately
verified.
These differences have been coordinated with the manufacturer.
Costs of Compliance
There are about 330 airplanes of the affected design in the
worldwide fleet. This proposed AD would affect about 131 airplanes of
U.S. registry. The proposed modification would take about 28 work hours
per airplane, at an average labor rate of $65 per work hour. Required
parts would cost between $4,717 and $9,099 per airplane. Based on these
figures, the estimated cost of the proposed AD for U.S. operators is
between $856,347 and $1,430,389, or between $6,537 and $10,919 per
airplane.
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 will not have federalism
implications under Executive Order 13132. This proposed 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 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. See the ADDRESSES section for a location
to examine the regulatory evaluation.
[[Page 10339]]
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
airworthiness directive (AD):
Boeing: Docket No. FAA-2005-20475; Directorate Identifier 2004-NM-
157-AD.
Comments Due Date
(a) The Federal Aviation Administration (FAA) must receive
comments on this AD action by April 18, 2005.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Boeing Model 777-200, -200ER, and -300
series airplanes, certificated in any category; as listed in Boeing
Special Attention Service Bulletin 777-53-0042, dated April 15,
2004.
Unsafe Condition
(d) This AD was prompted by reports of cracking of the aluminum
splice plates under the floor panels in the cabin aisle. We are
issuing this AD to prevent loss of the capability of the cabin floor
and seat track structure to support the airplane interior inertia
loads under emergency landing conditions. Loss of this support could
lead to galley or seat separation from attached restraints, which
could result in blocking of the emergency exits and consequent
injury to passengers and crew.
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.
Modification
(f) Within 60 months after the effective date of this AD: Except
as provided by paragraph (g) of this AD, modify the splice plate
assemblies installed under the floor panels at the forward and aft
edges of the cabin aisle (including replacement of damaged fasteners
with new fasteners) in accordance with Boeing Special Attention
Service Bulletin 777-53-0042, dated April 15, 2004.
(g) The referenced service bulletin recommends marking the
service bulletin number on the top of the floor panel assembly, but
this proposed AD does not require that action.
Alternative Methods of Compliance (AMOCs)
(h) 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.
Issued in Renton, Washington, on February 22, 2005.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 05-4073 Filed 3-2-05; 8:45 am]
BILLING CODE 4910-13-P