[Federal Register: July 2, 2008 (Volume 73, Number 128)]
[Rules and Regulations]
[Page 37778-37780]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr02jy08-3]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2006-26110; Directorate Identifier 2006-NM-112-AD;
Amendment 39-15585; AD 2008-13-22]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 747-400, 747-400D, and
747-400F Series Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule.
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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain Boeing Model 747-400, 747-400D, and 747-400F series airplanes.
This AD requires replacement of an electronic flight instrument system/
engine indicating and crew alerting system (EFIS/EICAS) interface unit
(EIU) located on the E2-6 shelf of the main equipment center with a new
or modified EIU. This AD results from two instances where all six
integrated display units (IDUs) on the flight deck panels went blank in
flight. We are issuing this AD to prevent loss of the IDUs due to
failure of all three EIUs, which could result in the inability of the
flightcrew to maintain safe flight and landing of the airplane.
DATES: This AD becomes effective August 6, 2008.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in the AD as of August 6,
2008.
ADDRESSES: 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 AD, the regulatory evaluation,
any comments received, and other information. The address for the
Docket Office (telephone 800-647-5527) is the Document Management
Facility, U.S. Department of Transportation, Docket Operations, M-30,
West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE.,
Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Jay Yi, Aerospace Engineer, Systems
and Equipment Branch, ANM-130S, FAA, Seattle Aircraft Certification
Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone
(425) 917-6494; fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
Discussion
The FAA issued a supplemental notice of proposed rulemaking (NPRM)
to amend 14 CFR part 39 to include an AD that would apply to certain
Boeing Model 747-400, 747-400D, and 747-400F series airplanes. That
supplemental NPRM was published in the Federal Register on August 23,
2007 (72 FR 48246). That supplemental NPRM proposed to require
replacement of an electronic flight instrument system/engine indicating
and crew alerting system (EFIS/EICAS) interface unit (EIU) located on
the E2-6 shelf of the main equipment center with a new or modified EIU.
We issued that supplemental NPRM to propose reducing the compliance
time for replacing the EIU.
Compliance With AD 2004-10-05, Amendment 39-13635
We have determined that in order to comply with both this AD and
the EIU replacements required by paragraph (d)(1) of AD 2004-10-05, at
least one of the three EIUs must be part number (P/N) 622-8589-105 and
the other two EIUs may be either P/N 622-8589-104 or P/N 622-8589-105.
(The installation of P/N 622-8589-105 is required by paragraph (f) of
this AD, and the installation of P/N 622-8589-104 is required by
paragraph (d)(1) of AD 2004-10-05.) Boeing has confirmed that P/N 622-
8589-104 and P/N 622-8589-105 are fully interchangeable and may be used
in any combination. Therefore, we have revised paragraph (h) of this AD
accordingly. In addition, we have removed the information that appeared
in paragraph (b) of the supplemental NPRM and included it in paragraph
(h) of this AD. These changes are necessary to ensure that operators
are able to comply with both this AD and AD 2004-10-05, in light of the
parts availability constraint.
Comments
We provided the public the opportunity to participate in the
development of this AD. We have considered the comments received.
Support for the Supplemental NPRM
The National Transportation Safety Board (NTSB) supports reducing
the compliance time from 60 months to 24 months. The Association of
Asia Pacific Airlines (AAPA) supports the intent of the supplemental
NPRM.
Request To Extend the Compliance Time
Boeing, Korean Air, Japan Airlines, United Airlines, and the AAPA
request that we extend the compliance time to 60 months for replacing
at least one EIU. As justification for extending the compliance time,
Boeing states that (1) the loss of primary displays has been
demonstrated and certified as not being a catastrophic condition, (2)
pilots are able to maintain continued safe flight and landing by using
backup or standby instruments as certified, and (3) mitigating action
has been provided with issuance of the Boeing 747-400 Flight Crew
Operations Maintenance Bulletin (OMB) TB1-20, ``Flight Deck Display
Unit Blanking Anomaly,'' dated February 25, 2003, to the Boeing 747
Flight Crew Operations Manual. Boeing further states that the EIU
manufacturer has advised that it has limited capacity to modify units,
which needs to be taken into consideration in the fleet modification
plan. Boeing also asserts that most operators will choose to modify all
three EIUs simultaneously to ease configuration control and logistics.
AAPA states that its member airlines operate about 50 percent of
the affected airplanes worldwide, and that none of its members have
reported any blanking of all integrated display units (IDUs). AAPA
further states that many of its members have already planned to replace
all three EIUs, but that the 24-month compliance time will require them
to change their existing retrofit programs to meet the new timeline.
AAPA asserts this schedule change could involve removing airplanes from
revenue service before scheduled maintenance, thus affecting their
operational flexibility (capacity, manpower, and revenue generation).
AAPA also states that the capacity of the EIU manufacturer must be
considered at the global level, as many operators have already started
their replacement programs based on replacing all three EIUs within a
60-month compliance time.
Korean Air states that the 24-month compliance time will impose an
excessive burden considering the parts availability constraint. United
Airlines and Japan Airlines state that replacing one EIU, instead of
all three EIUs, creates a risk that the requirements of the AD could be
inadvertently undone at a later time. They further state that replacing
all three EIUs, which can be done only within a 60-month compliance
time, will ensure that the
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requirements of the AD cannot be undone.
We do not agree to extend the compliance time for any of the stated
reasons. We also disagree with AAPA's assertion that none of its
members have experienced blanking of the IDUs; we have received a
report that one of its members experienced losing all IDUs on two Model
747-400 series airplanes. We have determined that a 24-month compliance
time is the longest acceptable compliance time for ensuring that an
acceptable level of safety is maintained, even with the mitigating
action mentioned by Boeing.
While the loss of the primary displays, by itself, is not
catastrophic in the same sense as other types of failures such as a
major structural failure, it is still considered to be unsafe. When all
primary displays are lost, flightcrew access to critical flight
management information is denied and flightcrew workload could be
significantly increased. In addition to the primary displays of
airplane flight and navigation data, such information includes engine
monitoring, depiction of hazardous weather and terrain, flightcrew
warnings, fuel management, and other vital systems information. Access
to this information is critical to the flightcrew's ability to maintain
airplane control, positional awareness, and awareness of the airplane's
condition. Conversely, a simultaneous loss of all of this information
unacceptably degrades the flightcrew's ability to continue safe flight
and landing. We have taken AD action on other airplane models that also
experienced loss of the primary displays.
We recognize that operators would prefer to replace all three EIUs
simultaneously for fleet management reasons, and that replacing only
one EIU involves more complicated maintenance planning. However,
operators' approved maintenance programs should provide sufficient
controls to minimize the risk of releasing airplanes for service in a
noncompliant condition. Further, the parts availability constraint will
prevent operators from replacing all three EIUs on all affected
airplanes within 24 months. The only course of action that likely can
be supported with adequate parts availability for a 24-month compliance
time is a requirement to replace one EIU. Although under the provisions
of paragraph (i) of this AD, we will consider requests for adjustments
to the compliance time if data are submitted to substantiate that such
an adjustment would provide an acceptable level of safety. We have
revised paragraph (i) of this AD to specify the information that must
be submitted with the request.
Request To Require Replacement of All Three EIUs
The NTSB reiterates its concern about requiring replacement of only
one EIU. The NTSB states that, despite the intended redundancy of three
EIUs, if only one EIU is replaced and that modified EIU suffers an
unrelated fault removing it from operation, an airplane is still
exposed to the potential for the IDUs to go blank since the other two
EIUs would not have the auto-restart capability. The NTSB urges that we
continue to work with the EIU manufacturer and operators to ensure that
all three EIUs are replaced with new or modified parts in a timely
manner.
We infer the NTSB requests that we revise this AD to require
replacement of all three EIUs. Although we understand the NTSB's
concern, we do not agree to revise this AD. We have performed a risk
assessment of a modified EIU failing and have determined that the risk
of failure of the modified EIU is remote enough that an acceptable
level of safety is maintained by replacing only one EIU. Further, since
we have reduced the compliance time, there are only enough modification
kits available for all operators to replace one EIU per airplane within
the 24-month compliance time. Further, operators have already indicated
that, for fleet management reasons, they are likely to replace all
three EIUs as more parts become available. Also, the unsafe condition
has been further mitigated by the Boeing 747-400 Flight Crew OMB TB1-
20, ``Flight Deck Display Unit Blanking Anomaly.'' That document
advises flightcrews of the problem and provides instructions for
restarting the EIUs should there be a display blanking problem during
operation. We have not revised this AD in this regard.
Request To Revise Work-Hour Estimate
AAPA states that the work-hour estimate in the supplemental NPRM is
without basis, and that time to remove, install, and test the EIU must
be included to accurately determine the time for performing the task.
Based on operator experience, AAPA asserts that the EIU modification,
replacement, and testing range between 6 to 40 hours per airplane.
We disagree with revising the work hour estimate. The cost
information in an AD describes only the direct costs of the specific
actions required by this AD. Based on the best data available, the
manufacturer provided the number of work hours necessary to do the
required actions. This number represents the time necessary to perform
only the actions actually required by this AD. We recognize that, in
doing the actions required by an AD, operators might incur incidental
costs in addition to the direct costs. The cost analysis in AD
rulemaking actions, however, typically does not include incidental
costs such as the time required to gain access and close up, time
necessary for planning, or time necessitated by other administrative
actions. Those incidental costs, which might vary significantly among
operators, are almost impossible to calculate. Therefore, we have not
revised this 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 in the supplemental NPRM.
Costs of Compliance
There are about 639 airplanes of the affected design in the
worldwide fleet. This AD affects about 79 airplanes of U.S. registry.
The required actions take about 1 work hour per airplane, at an average
labor rate of $80 per work hour. Required parts cost about $2,840 per
airplane (for one EIU). Based on these figures, the estimated cost of
this AD for U.S. operators is $230,680, or $2,920 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 AD will not have federalism
implications under Executive Order 13132. This AD will not have a
substantial direct effect on
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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):
2008-13-22 Boeing: Amendment 39-15585. Docket No. FAA-2006-26110;
Directorate Identifier 2006-NM-112-AD.
Effective Date
(a) This AD becomes effective August 6, 2008.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Boeing Model 747-400, 747-400D, and 747-
400F series airplanes, certificated in any category; as identified
in Boeing Service Bulletin 747-31-2368, Revision 1, dated July 24,
2006.
Unsafe Condition
(d) This AD results from two instances where all six integrated
display units (IDUs) on the flight deck panels went blank in flight.
We are issuing this AD to prevent loss of the IDUs due to failure of
all three electronic flight instrument system/engine indicating and
crew alerting system (EFIS/EICAS) interface units (EIUs), which
could result in the inability of the flightcrew to maintain safe
flight and landing of the airplane.
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.
Replacement
(f) Within 24 months after the effective date of this AD,
replace at least one of the three EIUs, part number (P/N) 622-8589-
104, located on the E2-6 shelf of the main equipment center with a
new or modified EIU, P/N 622-8589-105, in accordance with the
Accomplishment Instructions of Boeing Service Bulletin 747-31-2368,
Revision 1, dated July 24, 2006.
Note 1: Boeing Service Bulletin 747-31-2368, Revision 1, dated
July 24, 2006, refers to Rockwell Collins Service Bulletin EIU-7000-
31-502, dated March 21, 2006, as an additional source of service
information for modifying an EIU by adding auto restart circuitry,
which converts EIU P/N 622-8589-104 to P/N 622-8589-105.
Credit for Actions Done According to Previous Service Bulletin
(g) Actions done before the effective date of this AD in
accordance with Boeing Service Bulletin 747-31-2368, dated November
22, 2005 (Revision 1 of the service bulletin specifies that the
original issue is dated December 1, 2005), are acceptable for
compliance with the corresponding requirements of paragraph (f) of
this AD.
Terminating Action for AD 2004-10-05, Amendment 39-13635
(h) Replacing an EIU with a new or modified EIU in accordance
with paragraph (f) of this AD constitutes terminating action for the
EIU replacement of paragraph (d)(1) of AD 2004-10-05, provided that
the other two EIUs are replaced with EIUs having P/N 622-8589-104 or
P/N 622-8589-105. All other actions required by paragraph (d)(1) of
AD 2004-10-05 must be complied with.
Alternative Methods of Compliance (AMOCs)
(i)(1) The Manager, Seattle Aircraft Certification Office, FAA,
has the authority to approve AMOCs for this AD, if requested in
accordance with 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.
We will only grant a compliance time extension for this AD if the
requestor can show that it is unable to accomplish the minimum
requirements of the AD (i.e., one modified EIU for each airplane) by
the compliance time for reasons beyond its control, such as the
inability to obtain enough parts to comply with the minimum
requirements of the AD by the compliance time. Therefore, requests
to extend the compliance time for this AD must include the following
information:
(i) How many airplanes are included in the request,
(ii) An inventory of how many modified EIUs the requestor
currently has on hand,
(iii) A forecast inventory showing that the requestor will not
have enough modified EIUs available to accomplish the minimum AD
requirements (i.e., one modified EIU for each airplane) by the AD
compliance time, based upon the current inventory on hand and
delivery rates from the parts supplier,
(iv) Documentation of supplier delivery commitments for modified
EIUs or conversion kits, as applicable, including firm delivery
commitment dates, that will provide the requestor with an adequate
number of parts to be able to accomplish the minimum AD requirements
on its affected airplanes, and
(v) Documentation of maintenance facility schedule availability
for accomplishing the AD requirements on all airplanes included in
the request. We will not approve AMOC requests that propose
replacing or modifying all three EIUs in a time frame longer than 24
months instead of replacing or modifying one EIU within 24 months.
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.
Material Incorporated by Reference
(j) You must use Boeing Service Bulletin 747-31-2368, Revision
1, dated July 24, 2006, to do the actions required by this AD,
unless the AD specifies otherwise.
(1) The Director of the Federal Register approved the
incorporation by reference of this service information under 5
U.S.C. 552(a) and 1 CFR part 51.
(2) For service information identified in this AD, contact
Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington
98124-2207.
(3) You may review copies of the service information
incorporated by reference at the FAA, Transport Airplane
Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the
National Archives and Records Administration (NARA). For information
on the availability of this material at 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 June 8, 2008.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E8-14188 Filed 7-1-08; 8:45 am]
BILLING CODE 4910-13-P