[Federal Register: December 1, 2004 (Volume 69, Number 230)]
[Proposed Rules]
[Page 69832-69834]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr01de04-14]
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DEPARTMENT OF TRANSPORTATION (DOT)
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2004-19750; Directorate Identifier 2003-NM-192-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-600, -700, -700C, -
800, and -900 Series Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to supersede an existing airworthiness
directive (AD) that applies to all Boeing Model 737-600, -700, -700C, -
800, and -900 series airplanes. That AD currently requires either
determining exposure to runway deicing fluids containing potassium
formate, or performing repetitive inspections of certain electrical
connectors in the wheel well of the main landing gear (MLG) for
corrosion, and follow-on actions. This proposed AD would add a new
inspection requirement and related corrective actions. This proposed AD
is prompted by additional reports indicating that significant corrosion
of the electrical connectors in the wheel well of the MLG has also been
found on airplanes that land on runways treated with deicing fluids
containing potassium acetate. We are proposing this AD to prevent
corrosion and subsequent moisture ingress into the electrical
connectors, which could result in an electrical short and consequent
incorrect functioning of critical airplane systems essential to safe
flight and landing of the airplane, including fire warning systems.
DATES: We must receive comments on this proposed AD by January 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.
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 the service information identified in this proposed AD contact
Boeing Commercial Airplane Group, 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 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.
FOR FURTHER INFORMATION CONTACT: Technical Information: Binh Tran,
Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA,
Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton,
Washington 98055-4056; telephone (425) 917-6485; fax (425) 917-6590.
Plain language information: Marcia Walters, marcia.walters@faa.gov.
SUPPLEMENTARY INFORMATION:
Docket Management System (DMS)
The FAA has implemented new procedures for maintaining AD dockets
electronically. As of May 17, 2004, new AD actions are posted on DMS
and assigned a docket number. We track each action and assign a
corresponding directorate identifier. The DMS AD docket number is in
the form ``Docket No. FAA-2004-99999.'' The Transport Airplane
Directorate identifier is in the form ``Directorate Identifier 2004-NM-
999-AD.'' Each DMS AD docket also lists the directorate identifier
(``Old Docket Number'') as a cross-reference for searching purposes.
Comments Invited
We invite you to submit any written relevant data, views, or
arguments regarding this proposed AD. Send your comments to an address
listed under ADDRESSES. Include ``Docket No. FAA-2004-19750;
Directorate Identifier 2003-NM-192-AD'' at the beginning 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 received 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 our
docket Web site, anyone can find and read the 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 the DOT's complete Privacy Act Statement in the
Federal Register published on April 11, 2000 (65 FR 19477-78), or you
may visit http://dms.dot.gov.
We are reviewing the writing style we currently use in regulatory
documents. We are interested in your comments on whether the style of
this document is clear, and your suggestions to improve the clarity of
our communications that affect you. You can get more information about
plain language at http://www.faa.gov/language and http://www.plainlanguage.gov.Examining
the Docket
You can examine the AD docket 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 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
On July 29, 2002, we issued AD 2002-16-03, amendment 39-12842 (67
FR 52396, August 12, 2002), for all Boeing Model 737-600, -700, -700C,
-800, and -900 series airplanes. That AD requires either determining
exposure to runway deicing fluids containing potassium formate or
performing repetitive inspections of certain electrical connectors in
the wheel well of the main landing gear (MLG) for corrosion, and
follow-on actions. That AD was prompted by reports of significant
corrosion of the electrical connectors in the main wheel well. We
issued that AD to prevent such corrosion, which could result in
incorrect functioning of critical airplane systems essential to safe
flight and landing of the airplane, including fire warning systems.
Actions Since Existing AD was Issued
Since we issued AD 2002-16-03, we have received reports of
significant corrosion of the electrical connectors located in the wheel
well of the MLG on Model 737 series airplanes that land on runways
treated with deicing fluids containing potassium acetate. Investigation
revealed that the corrosive effects of potassium acetate on the
electrical connectors are similar to those of potassium formate, and
the
[[Page 69833]]
requirements in the existing AD do not account for exposure to deicing
fluids containing potassium acetate. Significant corrosion can lead to
loss of the cadmium plating of the electrical connectors and subsequent
moisture ingress into the connectors, which could result in an
electrical short and consequent incorrect functioning of critical
airplane systems essential to safe flight and landing of the airplane,
including fire warning systems.
Revised Service Information
We have reviewed Boeing Alert Service Bulletin 737-24A1148,
Revision 1, dated July 10, 2003 (the original issue was referenced in
the existing AD as the appropriate source of service information for
accomplishment of the actions). The service bulletin describes
procedures for inspecting electrical connectors (including the contacts
and backshells) of the line replaceable unit (LRU) in the wheel well of
the MLG for corrosion, and related corrective actions if necessary.
Signs of corrosion are the presence of moisture, corrosion pits, or
white-colored material buildup on the connectors; black or reddish
discoloration on the contacts; or loss of the olive-drab conversion
coating on the backshells. The related corrective actions include
cleaning the LRU connectors and applying corrosion inhibiting compound
(CIC) if no corrosion is found, and replacing the LRU with a new LRU
and applying CIC if corrosion is found. The service bulletin also
recommends an operational test of the affected systems after doing the
applicable actions. Accomplishing the actions specified in the revised
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 products
of this same type design. Therefore, we are proposing this AD, which
would supersede AD 2002-16-03. This proposed AD would require either
determining exposure to runway deicing fluids containing potassium
formate and/or potassium acetate, or performing repetitive inspections
of certain electrical connectors in the wheel well of the main landing
gear for corrosion, and significant/corrective actions if necessary.
This proposed AD would require you to use the service information
described previously to perform these actions, except as discussed
under ``Difference Between the Proposed AD and Service Information.''
Difference Between the Proposed AD and Service Information
The service bulletin specifies an ``examination'' for corrosion of
the electrical connectors in the MLG wheel well. For the purposes of
this AD, we have determined that the procedures in the service bulletin
constitute a ``detailed inspection.'' Note 1 of this proposed AD
defines that inspection.
Work Hour Rate Increase
We have reviewed the figures we have used over the past several
years to calculate AD costs to operators. To account for various
inflationary costs in the airline industry, we find it necessary to
increase the labor rate used in these calculations from $60 per work
hour to $65 per work hour. The cost impact information, below, reflects
this increase in the specified hourly labor rate.
Costs of Compliance
This proposed AD would affect about 587 airplanes of U.S. registry.
The new determination of airplane exposure would take about 1 work hour
per airplane, at an average labor rate of $65 per work hour. Based on
these figures, the estimated cost of the actions specified in this
proposed AD for U.S. operators is $38,155, or $65 per airplane, per
cycle.
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. 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 FAA amends Sec. 39.13 by removing amendment 39-12842 (67 FR
52396, August 12, 2002) and adding the following new airworthiness
directive (AD):
Boeing: Docket No. FAA-2004-19750; Directorate Identifier 2003-NM-
192-AD.
Comments Due Date
(a) The Federal Aviation Administration must receive comments on
this airworthiness directive (AD) action by January 18, 2005.
Affected ADs
(b) This AD supersedes AD 2002-16-03, amendment 39-12842.
Applicability
(c) This AD applies to all Model 737-600, -700, -700C, -800, and
-900 series airplanes; certificated in any category.
Unsafe Condition
(d) This AD was prompted by additional reports indicating that
significant corrosion of the electrical connectors in the wheel well
of the MLG has also been found on airplanes that land on runways
treated with deicing fluids containing potassium acetate. We are
issuing this AD to prevent corrosion and subsequent moisture ingress
into the electrical connectors, which could result in an electrical
short and consequent incorrect functioning of critical airplane
systems essential to safe flight and landing of the airplane,
including fire warning systems.
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.
Determine Airplane Exposure/Significant & Corrective Actions
(f) Except as required by paragraph (f)(1)(ii) of this AD:
Within 12 months after the effective date of this AD, do the actions
required by either paragraph (f)(1) or (f)(2) of this AD.
(1) Determine airplane exposure to runway deicing fluids
containing potassium formate or potassium acetate by reviewing
airport data on the type of components in the deicing fluid used at
airports that support airplane operations.
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(i) For airplanes that have not been exposed to potassium
formate or potassium acetate: Repeat the requirements in paragraph
(f) of this AD thereafter at intervals not to exceed 12 months.
(ii) For airplanes that have been exposed to potassium formate
or potassium acetate: Before further flight, do the inspection
required by paragraph (f)(2) of this AD.
(2) Do a detailed inspection of the electrical connectors,
including the contacts and backshells, of the line replaceable unit
(LRU) in the wheel well of the MLG for corrosion by doing all the
actions in accordance with the Accomplishment Instructions of Boeing
Alert Service Bulletin 737-24A1148, Revision 1, dated July 10, 2003.
Do any significant/corrective actions before further flight in
accordance with the service bulletin. Repeat the actions required by
paragraph (f)(1) of this AD thereafter at intervals not to exceed 12
months.
Note 1: For the purposes of this AD, a detailed inspection is
defined as: ``An intensive visual examination of a specific
structural area, system, installation, or assembly to detect damage,
failure, or irregularity. Available lighting is normally
supplemented with a direct source of good lighting at intensity
deemed appropriate by the inspector. Inspection aids such as mirror,
magnifying lenses, etc., may be used. Surface cleaning and elaborate
access procedures may be required.''
Alternative Methods of Compliance (AMOCs)
(g)(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) AMOCs approved previously in accordance with AD 2002-16-03,
amendment 39-12842, are not approved as AMOCs with this AD.
Issued in Renton, Washington, on November 17, 2004.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 04-26497 Filed 11-30-04; 8:45 am]
BILLING CODE 4910-13-P