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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 [www.gpo.gov]
[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:
     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: 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: 
Kelly.McGuckin@faa.gov.

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: 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.
    (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: Kelly.McGuckin@faa.gov.

(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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