[Federal Register Volume 77, Number 233 (Tuesday, December 4, 2012)]
[Proposed Rules]
[Pages 71731-71734]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-29177]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2012-1221; Directorate Identifier 2012-NM-151-AD]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
-----------------------------------------------------------------------
SUMMARY: We propose to adopt a new airworthiness directive (AD) for
certain The Boeing Company Model 777-200 and -300 series airplanes.
This proposed AD was prompted by reports of hydraulic fluid
contamination found in the strut forward dry bay. This proposed AD
would require repetitive general visual inspections of the strut
forward dry bay for the presence of hydraulic fluid, and related
investigative and corrective actions if necessary. We are proposing
this AD to detect and correct hydraulic fluid contamination of the
strut forward dry bay, which could result in hydrogen embrittlement of
the titanium forward engine mount bulkhead fittings, and consequent
inability of the fittings to carry engine loads, resulting in the loss
or departure of an engine. Hydraulic embrittlement could cause a
through-crack formation across the fittings through which an engine
fire could breach into the strut, resulting in an uncontained strut
fire.
DATES: We must receive comments on this proposed AD by January 18,
2013.
ADDRESSES: You may send comments, using the procedures found in 14 CFR
11.43 and 11.45, 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: Deliver to Mail address above 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, Attention: Data & Services Management, P.
O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone 206-544-5000,
extension 1;
[[Page 71732]]
fax 206-766-5680; Internet https://www.myboeingfleet.com. You may
review copies of the referenced service information at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. For
information on the availability of this material at the FAA, call 425-
227-1221.
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 (phone: 800-647-5527) is in the ADDRESSES
section. Comments will be available in the AD docket shortly after
receipt.
FOR FURTHER INFORMATION CONTACT: Kevin Nguyen, Aerospace Engineer,
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification
Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-
6501; fax: 425-917-6590; email: [email protected].
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send any written relevant data, views, or
arguments about this proposal. Send your comments to an address listed
under the ADDRESSES section. Include ``Docket No. FAA-2012-1221;
Directorate Identifier 2012-NM-151-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 received reports of hydraulic fluid contamination in the strut
forward dry bay caused by the clogged and blocked forward strut drain
lines not allowing fluids (water, fuel, engine oil and hydraulic) to
drain properly, resulting in fluids backing up to the dry bay. The
presence of hydraulic fluid and temperatures above 270 degrees
Fahrenheit can cause hydrogen embrittlement of the titanium forward
engine mount bulkhead fittings. This condition, if not corrected, could
result in the inability of the forward engine mount bulkhead fittings
to carry engine loads, resulting in the loss or departure of an engine;
or cause a through-crack formation across the fittings through which an
engine fire could breach into the strut, resulting in an uncontained
strut fire.
Relevant Service Information
We reviewed Boeing Special Attention Service Bulletin 777-54-0028,
dated May 25, 2012. The service information describes procedures for
repetitive general visual inspections for hydraulic fluid contamination
of the strut forward dry bay, and related investigative and corrective
actions if necessary. Related investigative actions include a detailed
inspection for hydraulic fluid coking, heat discoloration, damage to
sealant and primer, damage to leveling compound, cracking, and etching
or pitting of the interior strut forward dry bay; a detailed and high
frequency eddy current (HFEC) inspection for cracking, etching, or
pitting of the bulkhead upper and lower fittings of the strut forward
engine mount; and checking drain lines for blockage. Corrective actions
include cleaning and restoring sealant, primer, and leveling compound
of the detail parts in the strut forward dry bay; cleaning or replacing
drain lines; and contacting the manufacturer for repair instructions
and doing the repair.
The compliance time for the initial inspection is within 600 flight
cycles or 12 months, whichever occurs first. The compliance times for
the related investigative actions are before further flight. The
compliance times for corrective actions vary between before further
flight, and within 25 flight cycles or 10 days, whichever occurs first
(depending on the condition). The repetitive inspection intervals do
not exceed 1,200 flight cycles.
FAA's Determination
We are proposing this AD because we evaluated all the relevant
information and determined the unsafe condition described previously is
likely to exist or develop in other products of these same type
designs.
Proposed AD Requirements
This proposed AD would require accomplishing the actions specified
in the service information described previously, except as discussed
under ``Differences Between the Proposed AD and the Service
Information.''
Differences Between the Proposed AD and the Service Information
Although the service bulletin specifies that operators may contact
the manufacturer for disposition of certain repair conditions, this
proposed AD would require operators to repair those conditions using a
method approved by the FAA.
Costs of Compliance
We estimate that this proposed AD affects 55 airplanes of U.S.
registry.
We estimate the following costs to comply with this proposed AD:
Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
Action Labor cost Parts cost Cost per product Cost on U.S. operators
--------------------------------------------------------------------------------------------------------------------------------------------------------
Repetitive general visual 5 work-hours x $85 per hour $0 $425 per inspection $23,375 per inspection cycle.
inspections. = $425 per inspection cycle. cycle.
--------------------------------------------------------------------------------------------------------------------------------------------------------
We estimate the following costs to do any actions that would be
required based on the results of the proposed inspection. We have no
way of determining the number of aircraft that might need these
actions.
On-Condition Costs
----------------------------------------------------------------------------------------------------------------
Cost per
Action Labor cost Parts cost product
----------------------------------------------------------------------------------------------------------------
Detailed inspection........................... 8 work-hours x $85 per hour = $680.... $0 $680
[[Page 71733]]
Check drain lines (including cleaning or 5 work-hours x $85 per hour = $425.... 0 425
replacing).
Detailed inspection and high frequency eddy 8 work-hours x $85 per hour = $680.... 0 680
current inspection.
Clean and restore sealant, primer and leveling 8 work-hours x $85 per hour = $680.... 0 680
compound.
----------------------------------------------------------------------------------------------------------------
We have received no definitive data that would enable us to provide
a cost estimate for the on-condition repair specified in this proposed
AD.
According to the manufacturer, some of the costs of this proposed
AD may be covered under warranty, thereby reducing the cost impact on
affected individuals. We do not control warranty coverage for affected
individuals. As a result, we have included all costs in our cost
estimate.
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),
(3) Will not affect intrastate aviation in Alaska, and
(4) 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.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, 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):
The Boeing Company: Docket No. FAA-2012-1221; Directorate Identifier
2012-NM-151-AD.
(a) Comments Due Date
We must receive comments by January 18, 2013.
(b) Affected ADs
None.
(c) Applicability
This AD applies to The Boeing Company Model 777-200 and -300
series airplanes; certificated in any category; equipped with Pratt
& Whitney 4000 engines; as identified in Boeing Special Attention
Service Bulletin 777-54-0028, dated May 25, 2012.
(d) Subject
Joint Aircraft System Component (JASC)/Air Transport Association
(ATA) of America Code 54, Nacelles/pylons.
(e) Unsafe Condition
This AD was prompted by reports of hydraulic fluid contamination
found in the strut forward dry bay. We are issuing this AD to detect
and correct hydraulic fluid contamination of the strut forward dry
bay, which could result in hydrogen embrittlement of the titanium
forward engine mount bulkhead fittings, and consequent inability of
the fittings to carry engine loads, resulting in the loss or
departure of an engine. Hydraulic embrittlement could cause a
through-crack formation across the fittings through which an engine
fire could breach into the strut, resulting in an uncontained strut
fire.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Inspection
Except as provided by paragraph (h)(1) of this AD, at the times
specified in paragraph 1.E., ``Compliance,'' of Boeing Special
Attention Service Bulletin 777-54-0028, dated May 25, 2012: Do a
general visual inspection for hydraulic fluid contamination of the
interior of the strut forward dry bay, and do all applicable related
investigative and corrective actions, in accordance with the
Accomplishment Instructions of Boeing Special Attention Service
Bulletin 777-54-0028, dated May 25, 2012, except as required by
paragraph (h)(2) of this AD. Repeat the inspection thereafter at the
times specified in paragraph 1.E., ``Compliance,'' of Boeing Special
Attention Service Bulletin 777-54-0028, dated May 25, 2012. Except
as required by paragraph (h)(3) of this AD, do all applicable
related investigative and corrective actions at the times specified
in paragraph 1.E., ``Compliance,'' of Boeing Special Attention
Service Bulletin 777-54-0028, dated May 25, 2012.
(h) Exceptions
(1) Where the Compliance time column of paragraph 1.E.,
``Compliance,'' of Boeing Service Bulletin 777-54-0028, dated May
25, 2012, refers to the compliance time ``after the original issue
date of this service bulletin,'' this AD requires compliance within
the specified compliance time after the effective date of this AD.
(2) Where Boeing Special Attention Service Bulletin 777-54-0028,
dated May 25, 2012, specifies to contact Boeing for repair: Except
as required by paragraph (h)(3) of this AD, at the applicable times
specified in paragraph 1.E., ``Compliance,'' of Boeing Special
Attention Service Bulletin 777-54-0028, dated May 25, 2012, repair,
in accordance with a method approved by the Manager, Seattle
Aircraft Certification Office (ACO), FAA. 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) Where paragraph 1.E., ``Compliance,'' of Boeing Special
Attention Service Bulletin
[[Page 71734]]
777-54-0028, dated May 25, 2012, specifies a compliance time of
``within 25 flight-cycles or 10 days, whichever occurs first,'' this
AD requires compliance within 25 flight cycles or 10 days after the
most recent inspection required by paragraph (g) of this AD,
whichever occurs first.
(i) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Seattle Aircraft Certification Office (ACO),
FAA, has the authority to approve AMOCs for this AD, if requested
using the procedures found in 14 CFR 39.19. In accordance with 14
CFR 39.19, send your request to your principal inspector or local
Flight Standards District Office, as appropriate. If sending
information directly to the manager of the ACO, send it to the
attention of the person identified in the Related Information
section of this AD. Information may be emailed to: [email protected].
(2) Before using any approved AMOC, notify your appropriate
principal inspector, or lacking a principal inspector, the manager
of the local flight standards district office/certificate holding
district office.
(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 the
Boeing Commercial Airplanes Organization Designation Authorization
(ODA) that 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.
(j) Related Information
(1) For more information about this AD, contact Kevin Nguyen,
Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle
Aircraft Certification Office, 1601 Lind Avenue SW., Renton, WA
98057-3356; phone: 425-917-6501; fax: 425-917-6590; email:
[email protected].
(2) For service information identified in this AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P. O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone 206-544-
5000, extension 1; fax 206-766-5680; Internet https://www.myboeingfleet.com. You may review copies of the referenced
service information at the FAA, Transport Airplane Directorate, 1601
Lind Avenue SW., Renton, WA. For information on the availability of
this material at the FAA, call 425-227-1221.
Issued in Renton, Washington, on November 21, 2012.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2012-29177 Filed 12-3-12; 8:45 am]
BILLING CODE 4910-13-P