AD 2015-09-07
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Boeing | Various | Airworthiness Directives; The Boeing Company Airplanes |
Unsafe Condition
A Model 787 airplane that has been powered continuously for 248 days can lose all alternating current (AC) electrical power due to the generator control units (GCUs) simultaneously going into failsafe mode. This condition is caused by a software counter internal to the GCUs that will overflow after 248 days of continuous power.
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Required Actions
This AD requires a repetitive maintenance task for electrical power deactivation.
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Compliance Time
Within 50 flight hours after the effective date of this AD.
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Affected Aircraft
All The Boeing Company Model 787 airplanes, certificated in any category.
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Federal Register Abstract
We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 787 airplanes. This AD requires a repetitive maintenance task for electrical power deactivation on Model 787 airplanes. This AD was prompted by the determination that a Model 787 airplane that has been powered continuously for 248 days can lose all alternating current (AC) electrical power due to the generator control units (GCUs) simultaneously going into failsafe mode. This condition is caused by a software counter internal to the GCUs that will overflow after 248 days of continuous power. We are issuing this AD to prevent loss of all AC electrical power, which could result in loss of control of the airplane.
Applicability Source Text
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(c) Applicability
This AD applies to all The Boeing Company Model 787 airplanes,
certificated in any category.
Document Text
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[Federal Register Volume 80, Number 84 (Friday, May 1, 2015)]
[Rules and Regulations]
[Pages 24789-24791]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2015-10066]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2015-0936; Directorate Identifier 2015-NM-058-AD;
Amendment 39-18153; AD 2015-09-07]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule; request for comments.
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SUMMARY: We are adopting a new airworthiness directive (AD) for all The
Boeing Company Model 787 airplanes. This AD requires a repetitive
maintenance task for electrical power deactivation on Model 787
airplanes. This AD was prompted by the determination that a Model 787
airplane that has been powered continuously for 248 days can lose all
alternating current (AC) electrical power due to the generator control
units (GCUs) simultaneously going into failsafe mode. This condition is
caused by a software counter internal to the GCUs that will overflow
after 248 days of continuous power. We are issuing this AD to prevent
loss of all AC electrical power, which could result in loss of control
of the airplane.
DATES: This AD is effective May 1, 2015.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of May 1, 2015.
We must receive comments on this AD by June 15, 2015.
ADDRESSES: You may send comments, using the procedures found in 14 CFR
11.43 and 11.45, by any of the following methods:
<bullet> Federal eRulemaking Portal: Go to <a href="http://www.regulations.gov">http://www.regulations.gov</a>. Follow the instructions for submitting comments.
<bullet> Fax: 202-493-2251.
<bullet> 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.
<bullet> 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, 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 <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
You may view this 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. It
is also available on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by
searching for and locating Docket No. FAA-2015-0936.
Examining the AD Docket
You may examine the AD docket on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by searching for and locating Docket No. FAA-2015-
0936; 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 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: Kelly McGuckin, Aerospace Engineer,
Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft
Certification Office (ACO), 1601 Lind Avenue SW., Renton, WA 98057-
3356; phone: 425-917-6490; fax: 425-917-6590; email:
<a href="/cdn-cgi/l/email-protection#c982aca5a5b0e784aa8ebcaaa2a0a789afa8a8e7aea6bf"><span class="__cf_email__" data-cfemail="3b705e5757421576587c4e585052557b5d5a5a155c544d">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
We have been advised by Boeing of an issue identified during
laboratory testing. The software counter internal to the generator
control units (GCUs) will overflow after 248 days of continuous power,
causing that GCU to go into failsafe mode. If the four main GCUs
(associated with the engine mounted generators) were powered up at the
same time, after 248 days of continuous power, all four GCUs will go
into failsafe mode at the same time, resulting in a loss of all AC
electrical power regardless of flight phase.
FAA's Determination
We are issuing 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 the same type design.
AD Requirements
This AD requires a repetitive maintenance task for electrical power
deactivation.
Interim Action
We consider this AD interim action. The manufacturer is currently
developing a GCU software upgrade that will address the unsafe
condition identified in this AD. Once this software is developed,
approved, and available, we might consider additional rulemaking.
FAA's Justification and Determination of the Effective Date
An unsafe condition exists that requires the immediate adoption of
this AD. The FAA has found that the risk to the flying public justifies
waiving notice and comment prior to adoption of this rule. If the four
main GCUs were
[[Page 24790]]
powered up at the same time, after 248 days of continuous power, all
four GCUs will go into failsafe mode at the same time, resulting in a
loss of all AC electrical power regardless of flight phase. Loss of all
AC electrical power can result in loss of control of the airplane.
Therefore, we find that notice and opportunity for prior public comment
are impracticable and that good cause exists for making this amendment
effective in less than 30 days.
Comments Invited
This AD is a final rule that involves requirements affecting flight
safety and was not preceded by notice and an opportunity for public
comment. However, we invite you to send any written data, views, or
arguments about this AD. Send your comments to an address listed under
the ADDRESSES section. Include the docket number FAA-2015-0936 and
Directorate Identifier 2015-NM-058-AD at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of this AD. We will
consider all comments received by the closing date and may amend this
AD because of those comments.
We will post all comments we receive, without change, to <a href="http://www.regulations.gov">http://www.regulations.gov</a>, including any personal information you provide. We
will also post a report summarizing each substantive verbal contact we
receive about this AD.
Related Service Information Under 1 CFR Part 51
We reviewed Boeing Multi Operator Message MOM-MOM-15-0248-01B,
dated April 19, 2015; and Boeing Multi Operator Message MOM-MOM-15-
0248-01B(R1), dated April 20, 2015. The service information describes
procedures for electrical power deactivation of Model 787 airplanes.
This service information is reasonably available at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by searching for and locating Docket No. FAA-2015-
0936. Or see ADDRESSES for other ways to access this service
information.
Costs of Compliance
We estimate that this AD affects 28 airplanes of U.S. registry. We
estimate the following costs to comply with this AD:
Estimated Costs
----------------------------------------------------------------------------------------------------------------
Cost on U.S.
Action Labor cost Parts cost Cost per product operators
----------------------------------------------------------------------------------------------------------------
Electrical power deactivation 1 work-hour x $85 $0 $85 per deactivation $2,380 per
per hour = $85 per cycle. deactivation cycle.
deactivation cycle.
----------------------------------------------------------------------------------------------------------------
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
This AD will not have federalism implications under Executive Order
13132. This 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 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),
(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.
Adoption of the Amendment
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 FAA amends Sec. 39.13 by adding the following new airworthiness
directive (AD):
2015-09-07 The Boeing Company: Amendment 39-18153; Docket No. FAA-
2015-0936; Directorate Identifier 2015-NM-058-AD.
(a) Effective Date
This AD is effective May 1, 2015.
(b) Affected ADs
None.
(c) Applicability
This AD applies to all The Boeing Company Model 787 airplanes,
certificated in any category.
(d) Subject
Air Transport Association (ATA) of America Code 24, Electrical
power.
(e) Unsafe Condition
This AD was prompted by the determination that a Model 787
airplane that has been powered continuously for 248 days can lose
all alternating current (AC) electrical power due to the generator
control units (GCUs) simultaneously going into failsafe mode. This
condition is caused by a software counter internal to the GCUs that
will overflow after 248 days of continuous power. We are issuing
this AD to prevent loss of all AC electrical power, which could
result in loss of control of the airplane.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Repetitive Maintenance Task: Electrical Power Deactivation
At the latest of the times specified in paragraphs (g)(1),
(g)(2), and (g)(3) of this AD, accomplish electrical power
deactivation on
[[Page 24791]]
the airplane, in accordance with step 2) in ``DESIRED ACTION'' of
Boeing Multi Operator Message MOM-MOM-15-0248-01B, dated April 19,
2015; or Boeing Multi Operator Message MOM-MOM-15-0248-01B(R1),
dated April 20, 2015. The main and auxiliary power unit (APU)
batteries do not need to be disconnected when performing the
electrical power deactivation. Repeat the electrical power
deactivation thereafter at intervals not to exceed 120 days.
(1) Within 120 days after the last electrical power deactivation
in accordance with step 2) in ``DESIRED ACTION'' of Boeing Multi
Operator Message MOM-MOM-15-0248-01B, dated April 19, 2015; or
Boeing Multi Operator Message MOM-MOM-15-0248-01B(R1), dated April
20, 2015.
(2) Within 120 days after the date of issuance of the original
certificate of airworthiness or the date of issuance of the original
export certificate of airworthiness.
(3) Within 7 days after the effective date of this AD.
(h) Special Flight Permit
Special flight permits, as described in Section 21.197 and
Section 21.199 of the Federal Aviation Regulations (14 CFR 21.197
and 21.199), are not allowed.
(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 paragraph (j) of this AD.
Information may be emailed to: <a href="/cdn-cgi/l/email-protection#21180c606f6c0c72444055554d440c60626e0c606c6e620c7344505444525552614740400f464e57"><span class="__cf_email__" data-cfemail="bb8296faf5f696e8dedacfcfd7de96faf8f496faf6f4f896e9decacedec8cfc8fbdddada95dcd4cd">[email protected]</span></a>.
(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.
(j) Related Information
For more information about this AD, contact Kelly McGuckin,
Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA,
Seattle Aircraft Certification Office (ACO), 1601 Lind Avenue SW.,
Renton, WA 98057-3356; phone: 425-917-6490; fax: 425-917-6590;
email: <a href="/cdn-cgi/l/email-protection#ca81afa6a6b3e487a98dbfa9a1a3a48aacababe4ada5bc"><span class="__cf_email__" data-cfemail="c388a6afafbaed8ea084b6a0a8aaad83a5a2a2eda4acb5">[email protected]</span></a>.
(k) Material Incorporated by Reference
(1) The Director of the Federal Register approved the
incorporation by reference (IBR) of the service information listed
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) You must use this service information as applicable to do
the actions required by this AD, unless the AD specifies otherwise.
(i) Boeing Multi Operator Message MOM-MOM-15-0248-01B, dated
April 19, 2015. The date appears only on the first page of this
document.
(ii) Boeing Multi Operator Message MOM-MOM-15-0248-01B(R1),
dated April 20, 2015. The date appears only on the first page of
this document.
(3) 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 <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
(4) You may view this 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.
(5) You may view this service information that is incorporated
by reference 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 <a href="http://www.archives.gov/federal-register/cfr/ibr-locations.html">http://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.
Issued in Renton, Washington, on April 23, 2015.
Jeffrey E. Duven,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2015-10066 Filed 4-30-15; 8:45 am]
BILLING CODE 4910-13-P
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