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[Federal Register Volume 81, Number 28 (Thursday, February 11, 2016)]
[Proposed Rules]
[Pages 7249-7251]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-02761]

========================================================================
Proposed Rules
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains notices to the public of 
the proposed issuance of rules and regulations. The purpose of these 
notices is to give interested persons an opportunity to participate in 
the rule making prior to the adoption of the final rules.

========================================================================


Federal Register / Vol. 81, No. 28 / Thursday, February 11, 2016 / 
Proposed Rules

[[Page 7249]]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2015-5758; Notice No. 25-16-02-SC]

Special Conditions: The Boeing Company, Boeing Model 737-8 
Airplane; Non-Rechargeable Lithium Battery Installations

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed special conditions.

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SUMMARY: This action proposes special conditions for the Boeing Model 
737-8 airplane. This airplane will have a novel or unusual design 
feature when compared to the state of technology envisioned in the 
airworthiness standards for transport-category airplanes. This design 
feature is non-rechargeable lithium battery systems. The applicable 
airworthiness regulations do not contain adequate or appropriate safety 
standards for this design feature. These proposed special conditions 
contain the additional safety standards that the Administrator 
considers necessary to establish a level of safety equivalent to that 
established by the existing airworthiness standards.

DATES: Send your comments on or before March 28, 2016.

ADDRESSES: Send comments identified by docket number FAA-2015-5758 
using any of the following methods:
     Federal eRegulations Portal: Go to http://www.regulations.gov/ and follow the online instructions for sending 
your comments electronically.
     Mail: Send comments to Docket Operations, M-30, U.S. 
Department of Transportation (DOT), 1200 New Jersey Avenue SE., Room 
W12-140, West Building Ground Floor, Washington, DC, 20590-0001.
     Hand Delivery or Courier: Take comments to Docket 
Operations in Room W12-140 of the West Building Ground Floor at 1200 
New Jersey Avenue SE., Washington, DC, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
     Fax: Fax comments to Docket Operations at 202-493-2251.
    Privacy: The FAA will post all comments it receives, without 
change, to http://www.regulations.gov/, including any personal 
information the commenter provides. Using the search function of the 
docket Web site, anyone can find and read the electronic form of all 
comments received into any FAA docket, including the name of the 
individual sending the comment (or signing the comment for an 
association, business, labor union, etc.). DOT's complete Privacy Act 
Statement can be found in the Federal Register published on April 11, 
2000 (65 FR 19477-19478), as well as at http://DocketsInfo.dot.gov/.
    Docket: Background documents or comments received may be read at 
http://www.regulations.gov/ at any time. Follow the online instructions 
for accessing the docket or go to Docket Operations in Room W12-140 of 
the West Building Ground Floor at 1200 New Jersey Avenue SE., 
Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Nazih Khaouly, Airplane and Flight 
Crew Interface Branch, ANM-111, Transport Airplane Directorate, 
Aircraft Certification Service, 1601 Lind Avenue SW., Renton, 
Washington, 98057-3356; telephone 425-227-2432; facsimile 425-227-1149.

SUPPLEMENTARY INFORMATION:

Future Requests for Installation of Non-Rechargeable Lithium Batteries

    The FAA anticipates that non-rechargeable lithium batteries will be 
installed in other makes and models of airplanes. We have made the 
determination to require special conditions for all applications 
requesting the installation of non-rechargeable lithium batteries until 
the airworthiness requirements can be revised to address this issue. 
Having the same standards across the range of all transport-airplane 
makes and models will ensure regulatory consistency for the aviation 
industry.

Comments Invited

    We invite interested people to take part in this rulemaking by 
sending written comments, data, or views. The most helpful comments 
reference a specific portion of the special conditions, explain the 
reason for any recommended change, and include supporting data.
    We will consider all comments we receive by the closing date for 
comments. We may change these special conditions based on the comments 
we receive.

Background

    On January 27, 2012, The Boeing Company applied for an amendment to 
Type Certificate No. A16WE to include a new Model 737-8 airplane. The 
Model 737-8 airplane is a narrow-body, transport-category airplane that 
is a derivative of the Model 737-800 airplane with two CFM LEAP-1B 
wing-mounted engines.
    The Model 737-8 airplane will include non-rechargeable lithium 
batteries. The current battery requirements in Title 14, Code of 
Federal Regulations (14 CFR) part 25 are inadequate for addressing an 
airplane with lithium batteries.

Type Certification Basis

    Under the provisions of 14 CFR 21.101, The Boeing Company must show 
that the Model 737-8 airplane meets the applicable provisions of the 
regulations listed in Type Certificate A16WE or the applicable 
regulations in effect on the date of application for the change, except 
for earlier amendments as agreed upon by the FAA. The regulations 
listed in the type certificate are commonly referred to as the 
``original type certification basis.'' The regulations listed in Type 
Certificate No. A16WE are 14 CFR part 25 effective February 1, 1965 
including Amendments 25-1 through 25-77 with exceptions listed in the 
type certificate. In addition, the certification basis includes other 
regulations, special conditions, and exemptions that are not relevant 
to these proposed special conditions. Type Certificate No. A16WE will 
be updated to include a complete description of the certification basis 
for this airplane model.
    In addition to the applicable airworthiness regulations and special 
conditions, the Model 737-8 airplane

[[Page 7250]]

must comply with the fuel-vent and exhaust-emission requirements of 14 
CFR part 34, and the noise-certification requirements of 14 CFR part 
36.
    If the Administrator finds that the applicable airworthiness 
regulations (i.e., 14 CFR part 25) do not contain adequate or 
appropriate safety standards for the Model 737-8 airplane because of a 
novel or unusual design feature, special conditions are prescribed 
under the provisions of Sec.  21.16.
    Special conditions are initially applicable to the model for which 
they are issued. Should the type certificate for that model be amended 
later to include any other model that incorporates the same or similar 
novel or unusual design feature, or should any other model already 
included on the same type certificate be modified to incorporate the 
same novel or unusual design feature, these special conditions would 
also apply to the other model under Sec.  21.101.
    The FAA issues special conditions, as defined in 14 CFR 11.19, in 
accordance with Sec.  11.38, and they become part of the type-
certification basis under Sec.  21.101.

Novel or Unusual Design Features

    A battery system consists of the battery and any protective, 
monitoring and alerting circuitry or hardware inside or outside of the 
battery and venting capability where necessary. For the purpose of 
these special conditions, we refer to a battery and battery system as a 
battery. The Model 737-8 airplane will incorporate non-rechargeable 
lithium batteries, which are novel or unusual design features.

Discussion

    We derived the current regulations governing installation of 
batteries in transport-category airplanes from Civil Air Regulations 
(CAR) 4b.625(d) as part of the re-codification of CAR 4b that 
established 14 CFR part 25 in February 1965. We basically reworded the 
battery requirements, which are currently in Sec.  25.1353(b)(1) 
through (b)(4), from the CAR requirements. Non-rechargeable lithium 
batteries are novel and unusual with respect to the state of technology 
considered when these requirements were codified. These batteries 
introduce higher energy levels into airplane systems through new 
chemical compositions in various battery-cell sizes and construction. 
Interconnection of these cells in battery packs introduces failure 
modes that require unique design considerations, such as provisions for 
thermal management.
    Recent events involving rechargeable and non-rechargeable lithium 
batteries prompted the FAA to initiate a broad evaluation of these 
energy-storage technologies. In January 2013, two independent events 
involving rechargeable lithium-ion batteries demonstrated unanticipated 
failure modes. A National Transportation Safety Board (NTSB) letter to 
the FAA, dated May 22, 2014, which is available at http://www.ntsb.gov, 
filename A-14-032-036.pdf, describes these events.
    On July 12, 2013, an event involving a non-rechargeable lithium 
battery, in an emergency locator transmitter installation, demonstrated 
unanticipated failure modes. Air Accident Investigations Branch 
Bulletin S5/2013 describes this event.
    Some other known uses of rechargeable and non-rechargeable lithium 
batteries on airplanes include:
     Flight deck and avionics systems such as displays, global 
positioning systems, cockpit voice recorders, flight data recorders, 
underwater locator beacons, navigation computers, integrated avionics 
computers, satellite network and communication systems, communication-
management units, and remote-monitor electronic line-replaceable units 
(LRU);
     Cabin safety, entertainment, and communications equipment, 
including life rafts, escape slides, seatbelt air bags, cabin 
management systems, Ethernet switches, routers and media servers, 
wireless systems, internet and in-flight entertainment systems, 
satellite televisions, remotes, and handsets;
     Systems in cargo areas including door controls, sensors, 
video surveillance equipment, and security systems.
    Some known potential hazards and failure modes associated with non-
rechargeable lithium batteries are:

 Internal failures

    In general, these batteries are significantly more susceptible to 
internal failures that can result in self-sustaining increases in 
temperature and pressure (i.e., thermal runaway) than their nickel-
cadmium or lead-acid counterparts. The metallic lithium can ignite, 
resulting in a self-sustaining fire or explosion.

 Fast or imbalanced discharging

    Fast discharging or an imbalanced discharge of one cell of a multi-
cell battery may create an overheating condition that results in an 
uncontrollable venting condition, which in turn leads to a thermal 
event or an explosion.

 Flammability

    Unlike nickel-cadmium and lead-acid batteries, these batteries use 
higher energy and current in an electrochemical system that can be 
configured to maximize energy storage of lithium. They also use liquid 
electrolytes that can be extremely flammable. The electrolyte, as well 
as the electrodes, can serve as a source of fuel for an external fire 
if the battery casing is breached.
    Proposed Special Condition 1 requires that each individual cell 
within a battery be designed to maintain safe temperatures and 
pressures. Proposed Special Condition 2 addresses these same issues but 
for the entire battery. Proposed Special Condition 2 requires the 
battery be designed to prevent propagation of a thermal event, such as 
self-sustained, uncontrolled increases in temperature or pressure from 
one cell to adjacent cells.
    Proposed Special Conditions 1 and 2 are intended to ensure that the 
battery and its cells are designed to eliminate the potential for 
uncontrolled failures. However, a certain number of failures will occur 
due to various factors beyond the control of the designer. Therefore, 
other special conditions are intended to protect the airplane and its 
occupants if failure occurs.
    Proposed Special Conditions 3, 9 and 10 are self-explanatory, and 
the FAA does not provide further explanation for them at this time.
    The FAA proposes Special Condition 4 to make it clear that the 
flammable-fluid fire-protection requirements of Sec.  25.863 apply to 
non-rechargeable lithium battery installations. Section 25.863 is 
applicable to areas of the airplane that could be exposed to flammable 
fluid leakage from airplane systems. Non-rechargeable lithium batteries 
contain electrolyte that is a flammable fluid.
    Proposed Special Condition 5 requires each non-rechargeable lithium 
battery installation to not damage surrounding structure or adjacent 
systems, equipment, or electrical wiring from corrosive fluids or gases 
that may escape. Proposed Special Condition 6 requires each non-
rechargeable lithium battery installation to have provisions to prevent 
any hazardous effect on airplane structure or systems caused by the 
maximum amount of heat it can generate due to any failure of it or its 
individual cells. The means of meeting these proposed special 
conditions may be the same, but they are independent requirements 
addressing different hazards. Proposed Special Condition 5 addresses 
corrosive fluids and gases, whereas Proposed Special Condition 6 
addresses heat.
    Proposed Special Conditions 7 and 8 require non-rechargeable 
lithium

[[Page 7251]]

batteries to have automatic means for battery disconnection and control 
of battery discharge rate due to the fast-acting nature of lithium-
battery chemical reactions. Manual intervention would not be timely or 
effective in mitigating the hazards associated with these batteries.
    These special conditions will apply to all non-rechargeable lithium 
battery installations in lieu of Sec.  25.1353(b)(1) through (b)(4) at 
Amendment 25-123. Sections 25.1353(b)(1) through (b)(4) at Amendment 
25-123 will remain in effect for other battery installations.
    These proposed special conditions contain the additional safety 
standards that the Administrator considers necessary to establish a 
level of safety equivalent to that established by the existing 
airworthiness standards.

Applicability

    As discussed above, these special conditions are applicable to the 
Boeing Model 737-8 airplane. Should the applicant apply at a later date 
for a change to the type certificate to include another model 
incorporating the same novel or unusual design feature, or should any 
other model already included on the same type certificate be modified 
to incorporate the same novel or unusual design feature, these special 
conditions would apply to that model as well.

Conclusion

    This action affects only certain novel or unusual design features 
on one model of airplane. It is not a rule of general applicability.

List of Subjects in 14 CFR Part 25

    Aircraft, Aviation safety, Reporting and record keeping 
requirements.

0
The authority citation for these special conditions continues to read 
as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, 44704.

The Proposed Special Conditions

0
Accordingly, the FAA proposes the following special conditions as part 
of the type certification basis for Boeing Model 737-8 airplane.

Non-Rechargeable Lithium Battery Installations

    In lieu of Sec.  25.1353(b)(1) through (b)(4) at Amendment 25-123, 
each non-rechargeable lithium battery installation must:
    1. Maintain safe cell temperatures and pressures under all 
foreseeable operating conditions to prevent fire and explosion.
    2. Prevent the occurrence of self-sustaining, uncontrolled 
increases in temperature or pressure.
    3. Not emit explosive or toxic gases, either in normal operation or 
as a result of its failure, that may accumulate in hazardous quantities 
within the airplane.
    4. Meet the requirements of Sec.  25.863.
    5. Not damage surrounding structure or adjacent systems, equipment, 
or electrical wiring from corrosive fluids or gases that may escape.
    6. Have provisions to prevent any hazardous effect on airplane 
structure or systems caused by the maximum amount of heat it can 
generate due to any failure of it or its individual cells.
    7. Be capable of automatically controlling the discharge rate of 
each cell to prevent cell imbalance, back-charging, overheating, and 
uncontrollable temperature and pressure.
    8. Have a means to automatically disconnect from its discharging 
circuit in the event of an over-temperature condition, cell failure or 
battery failure.
    9. Have a failure sensing and warning system to alert the 
flightcrew if its failure affects safe operation of the airplane.
    10. Have a means for the flightcrew or maintenance personnel to 
determine the battery charge state if the battery's function is 
required for safe operation of the airplane.

    Note 1: A battery system consists of the battery and any 
protective, monitoring and alerting circuitry or hardware inside or 
outside of the battery. It also includes vents (where necessary) and 
packaging. For the purpose of these special conditions, a battery 
and battery system are referred to as a battery.

    Issued in Renton, Washington, on February 4, 2016.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2016-02761 Filed 2-10-16; 8:45 am]
 BILLING CODE 4910-13-P
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