
[Federal Register Volume 82, Number 193 (Friday, October 6, 2017)]
[Proposed Rules]
[Pages 46719-46721]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-21365]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2017-0904; Product Identifier 2017-NM-071-AD]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for 
certain The Boeing Company Model 787-8 and 787-9 airplanes. This 
proposed AD was prompted by a report of an in-service reliability issue 
of a latent flow sensor failure combined with single cabin air 
compressor (CAC) operation. This condition resulted in reduced airflow 
which led to a persistent single CAC surge condition that caused 
overheat damage to the CAC inlet. This proposed AD would require 
installing new pack control unit (PCU) software for the cabin air 
conditioning and temperature control system (CACTCS) and new CAC outlet 
pressure sensor J-tube hardware, and doing related investigative and 
corrective actions if necessary. We are proposing this AD to address 
the unsafe condition on these products.

DATES: We must receive comments on this proposed AD by November 20, 
2017.

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 NPRM, contact Boeing 
Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 
2600 Westminster Blvd., MC 110 SK57, Seal Beach, CA 90740-5600; 
telephone: 562-797-1717; Internet: https://www.myboeingfleet.com. You 
may view this service information at the FAA, Transport Standards 
Branch, 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-2017-0904.

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-2017-
0904; 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

[[Page 46720]]

contains this NPRM, 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: Caspar Wang, Aerospace Engineer, Cabin 
Safety and Environmental Systems Section, FAA, Seattle ACO Branch, 1601 
Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6414; fax: 425-
917-6590; email: caspar.wang@faa.gov.

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-2017-0904; 
Product Identifier 2017-NM-071-AD'' at the beginning of your comments. 
We specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of this NPRM. We will consider all 
comments received by the closing date and may amend this NPRM 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 NPRM.

Discussion

    Boeing Model 787-8 and 787-9 airplanes have two air conditioning 
packs, one on each side of the airplane. Each pack contains two CACs 
that function together under normal operating conditions. The Smarter 
Environmental Control System ensures that airflow is distributed 
equally across the CACs. If the airflow is low, a single operating CAC 
on a pack can be driven into an undetected surge. We have received a 
report of an in-service reliability issue involving a latent flow 
sensor failure combined with single CAC operation, which resulted in 
reduced airflow and a persistent single CAC surge condition. During the 
surge, the temperature exceeded the 450-degree Fahrenheit maximum 
allowable temperature and generated enough heat energy to degrade the 
structural integrity of the CAC inlet. The PCU software logic was only 
designed to detect the surge when both CACs were operating on the same 
pack, and therefore, it was unable to detect a persistent single CAC 
surge condition which led to CAC inlet overheating. This overheating 
condition resulted in structural degradation of the CAC inlet, fumes in 
the cabin and flight deck, and interruption to in-service air 
conditioning.
    In addition, we received a report of an in-service event involving 
foreign object debris in the CAC inlet and accumulation at the ozone 
converter that also led to a persistent single CAC surge resulting in 
overheat damage to the CAC inlet housing. The proposed PCU software 
change would redistribute the airflow to provide more flow to a single 
CAC, reducing the potential for a CAC surge. Reduced airflow leading to 
persistent CAC surge conditions and CAC inlet overheating, if not 
corrected, could result in structural degradation of the CAC inlet, and 
fumes in the cabin and flight deck, as well as causing interruption to 
in-service air conditioning.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Service Bulletin B787-81205-SB210075-00, Issue 
003, dated March 29, 2017; and Boeing Service Bulletin B787-81205-
SB210077-00, Issue 003, dated October 20, 2016. The service information 
describes procedures for installing new PCU software for the CACTCS and 
new CAC outlet pressure sensor J-tube hardware, and doing related 
investigative and corrective actions. These documents are distinct 
since they apply to different airplane models. This service information 
is reasonably available because the interested parties have access to 
it through their normal course of business or by the means identified 
in the ADDRESSES section.

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 the same type design.

Proposed AD Requirements

    This proposed AD would require accomplishing the actions specified 
in the service information described previously. For information on the 
procedures and compliance times, see this service information at http://www.regulations.gov by searching for and locating Docket No. FAA-2017-
0904.
    The phrase ``related investigative actions'' is used in this 
proposed AD. Related investigative actions are follow-on actions that 
(1) are related to the primary action, and (2) further investigate the 
nature of any condition found. Related investigative actions in an AD 
could include, for example, inspections.
    The phrase ``corrective actions'' is used in this proposed AD. 
Corrective actions correct or address any condition found. Corrective 
actions in an AD could include, for example, repairs.

Costs of Compliance

    We estimate that this proposed AD affects 62 airplanes of U.S. 
registry. We estimate the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
               Action                         Labor cost            Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Software Installation..............  1 work-hour x $85 per hour               $0             $85          $5,270
                                      = $85.
Modify Left and Right Inboard and    20 work-hours x $85 per              22,821          24,521       1,520,302
 Outboard CAC Modules.                hour = $1,700.
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    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition actions specified in this proposed 
AD.

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

[[Page 46721]]

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.
    This proposed AD is issued in accordance with authority delegated 
by the Executive Director, Aircraft Certification Service, as 
authorized by FAA Order 8000.51C. In accordance with that order, 
issuance of ADs is normally a function of the Compliance and 
Airworthiness Division, but during this transition period, the 
Executive Director has delegated the authority to issue ADs applicable 
to transport category airplanes to the Director of the System Oversight 
Division.

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

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):

The Boeing Company: Docket No. FAA-2017-0904; Product Identifier 
2017-NM-071-AD.

(a) Comments Due Date

    We must receive comments by November 20, 2017.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model 787-8 and 787-9 
airplanes, certificated in any category, as identified in the 
applicable service information specified in paragraphs (c)(1) and 
(c)(2) of this AD.
    (1) Boeing Service Bulletin B787-81205-SB210075-00, Issue 003, 
dated March 29, 2017 (for Model 787-8 airplanes).
    (2) Boeing Service Bulletin B787-81205-SB210077-00, Issue 003, 
dated October 20, 2016 (for Model 787-9 airplanes).

(d) Subject

    Air Transport Association (ATA) of America Code 21, Air 
conditioning.

(e) Unsafe Condition

    This AD was prompted by a report of an in-service reliability 
issue involving a latent flow sensor failure combined with single 
cabin air compressor (CAC) operation. This condition resulted in 
reduced airflow which led to a persistent single CAC surge condition 
that caused overheat damage to the CAC inlet. We are issuing this AD 
to prevent CAC inlet overheating leading to structural degradation 
of the CAC inlet, fumes in the cabin and flight deck, and 
interruption to in-service air conditioning.

(f) Compliance

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

(g) Software and Hardware Installation

    Within 36 months after the effective date of this AD: Install 
new pack control unit software for the cabin air conditioning and 
temperature control system and new CAC outlet pressure sensor J-tube 
hardware, and do all applicable related investigative and corrective 
actions; in accordance with the Accomplishment Instructions of the 
applicable service information specified in paragraphs (g)(1) or 
(g)(2) of this AD. Related investigative and corrective actions must 
be done before further flight.
    (1) For Boeing Model 787-8 airplanes: Boeing Service Bulletin 
B787-81205-SB210075-00, Issue 003, dated March 29, 2017.
    (2) For Boeing Model 787-9 airplanes: Boeing Service Bulletin 
B787-81205-SB210077-00, Issue 003, dated October 20, 2016.

(h) Credit for Previous Actions

    This paragraph provides credit for the actions specified in 
paragraph (g) of this AD, if those actions were performed before the 
effective date of this AD using the applicable service information 
specified in paragraphs (h)(1) or (h)(2) of this AD.
    (1) Boeing Service Bulletin B787-81205-SB210075-00, Issue 002, 
dated May 11, 2016 (for Model 787-8 airplanes).
    (2) Boeing Service Bulletin B787-81205-SB210077-00, Issue 002, 
dated May 11, 2016 (for Model 787-9 airplanes).

(i) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Seattle ACO Branch, 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 certification office, send it to the attention of the 
person identified in paragraph (j)(1) 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.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair, modification, or alteration 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 Branch, to make those findings. To be approved, 
the repair method, modification deviation, or alteration deviation 
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 Caspar Wang, 
Aerospace Engineer, Cabin Safety and Environmental Systems Section, 
FAA, Seattle ACO Branch, 1601 Lind Avenue SW., Renton, WA 98057-
3356; phone: 425-917-6414; fax: 425-917-6590; email: 
caspar.wang@faa.gov.
    (2) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Contractual & Data Services 
(C&DS), 2600 Westminster Blvd., MC 110 SK57, Seal Beach, CA 90740-
5600; telephone: 562-797-1717; Internet: https://www.myboeingfleet.com. You may view this service information at the 
FAA, Transport Standards Branch, 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 September 25, 2017.
Dionne Palermo,
Acting Director, System Oversight Division, Aircraft Certification 
Service.
[FR Doc. 2017-21365 Filed 10-5-17; 8:45 am]
BILLING CODE 4910-13-P


