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Published 2015-05-01 · Federal Register document 2015-10066

Airworthiness Directives; The Boeing Company Airplanes

Publication 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.

Why this record is shown

Source: Federal Register annual FAA metadata. Acquired 2026-09-03T22:23:48.517946+00:00. The title, summary and date are source facts.

Source revision
federal_register_ad_metadata_2015-3bb842c840a7e6e6
Source row
results[96]
Raw source SHA-256
3bb842c840a7e6e6e43779ca68008e1e63ad8287ad840c3a981d1f66a934b14b

Final-rule publication

Recorded publication clauses

AD identifier printed in this edition
2015-09-07
Effective date printed in this edition
2015-05-01
Read 11 complete recorded clauses
Effective Date
(a) Effective Date

    This AD is effective May 1, 2015.

Exact source excerpt. Text positions 10698–10757, end exclusive, in the original decoded publication. SHA-256: 35bf558e5bb6f08d5862ed76e89a0572666834d2d3ea50b3d8aa4a3cf6848e11

Affected ADs
(b) Affected ADs

    None.

Exact source excerpt. Text positions 10757–10786, end exclusive, in the original decoded publication. SHA-256: 871a4afc60ceeae06e8010585055188633d616078500c45937092bfe892239c0

Applicability wording · Applicability
(c) Applicability

    This AD applies to all The Boeing Company Model 787 airplanes, 
certificated in any category.

Exact source excerpt. Text positions 10786–10904, end exclusive, in the original decoded publication. SHA-256: 43c4daec06371f016cdd9c667ac1ddcd12de426fbdb06c18a464b67c077e351f

Subject
(d) Subject

    Air Transport Association (ATA) of America Code 24, Electrical 
power.

Exact source excerpt. Text positions 10904–10993, end exclusive, in the original decoded publication. SHA-256: 255ad8dea90f73c6c0904fcd7f65ac20d65a0da0af7ff85531f827e632a9c83d

Unsafe Condition
(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.

Exact source excerpt. Text positions 10993–11526, end exclusive, in the original decoded publication. SHA-256: c8727a62c6489f5bc3db207b507d4d2acf75d5050d3dabb16b50138d5e09aff4

Compliance
(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

Exact source excerpt. Text positions 11526–11628, end exclusive, in the original decoded publication. SHA-256: 00fbfa31932483f627d0ce0a11cbd2e35e15d9231842b91ac85623ce533912d3

Repetitive Maintenance Task: Electrical Power Deactivation
(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.

Exact source excerpt. Text positions 11628–12808, end exclusive, in the original decoded publication. SHA-256: 6bb959ec687cdb1c9a141ec92faa55756eed28cb46859050ffd410571a60fd3d

Special Flight Permit
(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.

Exact source excerpt. Text positions 12808–12997, end exclusive, in the original decoded publication. SHA-256: 0ab5bbe64b13d96e843f3110b18210063c57e770d9954807977ee8b9d1be5c6e

Alternative Methods of Compliance (AMOCs)
(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: [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.

Exact source excerpt. Text positions 12997–13771, end exclusive, in the original decoded publication. SHA-256: 37661751426954bcbbd7de920a0d2b7d4b46d078951040c04c2fc683f1d9ff23

Related Information
(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: [email protected].

Exact source excerpt. Text positions 13771–14086, end exclusive, in the original decoded publication. SHA-256: ecb97c1bc3e2b2ceb2c37cb40fd4682dcd3e7d7e6e29979cd44a9b8e0f25f90a

Material Incorporated by Reference
(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 https://www.myboeingfleet.com.
    (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 http://www.archives.gov/federal-register/cfr/ibr-locations.html.

Exact source excerpt. Text positions 14086–15522, end exclusive, in the original decoded publication. SHA-256: cdf18fa8dba6e9ef0b4dbd482d0e34b7a5f687ec4d419bac36aa3330ddaeea53

No replacement link has been established from this edition. The complete historical rule chain and current legal effect remain unknown.

Find all recorded historical references to AD 2015-09-07 · 1 printed reference observations in this pinned collection.

These are observations from one dated publication. Current legal status is unknown; aircraft applicability, installed configuration, compliance and burden require separate evidence. Missing or unparsed conditions remain unknown.

Why these observations are shown

They were extracted offline from the same immutable official HTML source as the complete recorded text. The dated source wording, original text coordinates and exact quote digests are retained. PDF/text agreement and current regulatory effect have not been qualified.

Observation revision: whole-ad-publication-clause-observations-1.0.1. Text SHA-256: bee6dde4d4c5feff4cd7d913aa77f1d180d85cca2f2319a040fb134420fba670. Source manifest: 704cae7b5e68589f7583b82b7c85106015bdbe77e39a379cba3eadb423d04816.

Official source · 2015-05-01

Publication text

This is the complete recorded text of this dated publication.

Current legal effect is unknown. Aircraft applicability, installed configuration and compliance require separate evidence. PDF/text agreement has not been evaluated.

Read the complete official publication text
[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 [www.gpo.gov]
[FR Doc No: 2015-10066]


=======================================================================
-----------------------------------------------------------------------

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.

-----------------------------------------------------------------------

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 http://www.regulations.gov. 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 https://www.myboeingfleet.com. 
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 http://www.regulations.gov by 
searching for and locating Docket No. FAA-2015-0936.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov 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: 
[email protected].

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 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 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 http://www.regulations.gov 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: [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.

(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: [email protected].

(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 https://www.myboeingfleet.com.
    (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 http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    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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Text SHA-256
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These are dated publication metadata, recorded clauses and literal source observations. Word, model-label, header and reference matches do not establish current legal effect, manufacturer/model identity, aircraft applicability, installed configuration or compliance.

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