[Federal Register Volume 87, Number 219 (Tuesday, November 15, 2022)]
[Rules and Regulations]
[Pages 68336-68338]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-24773]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2022-0760; Special Conditions No. 25-827-SC]


Special Conditions: Aptoz EHF; Non-Rechargeable Lithium Batteries 
and Battery System Installations

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final special conditions; request for comments.

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SUMMARY: These special conditions are issued for a supplemental type 
certificate (STC) to install non-rechargeable lithium batteries and 
battery systems on certain transport-category airplanes. The airplanes, 
as modified by Aptoz EHF (Aptoz), 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 batteries and battery system in 
emergency locator transmitters (ELTs). The applicable airworthiness 
regulations do not contain adequate or appropriate safety standards for 
this design feature. These 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: This action is effective on Aptoz on November 15, 2022. Send 
comments on or before December 30, 2022.

ADDRESSES: Send comments identified by Docket No. FAA-2022-0760 using 
any of the following methods:
     Federal eRegulations Portal: Go to https://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: Except for Confidential Business Information (CBI) as 
described in the following paragraph, and other information as 
described in title 14, Code of Federal Regulations (14 CFR) 11.35, the 
FAA will post all comments received without change to https://www.regulations.gov/, including any personal information you provide. 
The FAA will also post a report summarizing each substantive verbal 
contact received about these special conditions.
    Except for Confidential Business Information as described in the 
following paragraph, and other information as described in 14 CFR 
11.35, the FAA will file in the docket all comments received concerning 
these special conditions. The FAA will consider all comments received 
on or before the closing date for comments. The FAA will consider 
comments filed late if it is possible to do so without incurring delay. 
The FAA may change these special conditions based on comments received.
    Confidential Business Information: Confidential Business 
Information (CBI) is commercial or financial information that is both 
customarily and actually treated as private by its owner. Under the 
Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from 
public disclosure. If your comments responsive to these special 
conditions contain commercial or financial information that is 
customarily treated as private, that you actually treat as private, and 
that is relevant or responsive to these special conditions, it is 
important that you clearly designate the submitted comments as CBI. 
Please mark each page of your submission containing CBI as ``PROPIN.'' 
The FAA will treat such marked submissions as confidential under the 
FOIA, and the indicated comments will not be placed in the public 
docket of these special conditions. Send submissions containing CBI to 
Nazih Khaouly, Aircraft Systems Section, AIR-673, Technical Innovation 
Policy Branch, Policy and Innovation Division, Aircraft Certification 
Service, Federal Aviation Administration, 2200 South 216th Street, Des 
Moines, Washington 98198; telephone and fax 206-231-3160; email 
[email protected]. Comments the FAA receives, which are not 
specifically designated as CBI, will be placed in the public docket for 
these special conditions.
    Docket: Background documents or comments received may be read at 
https://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,

[[Page 68337]]

DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays.

FOR FURTHER INFORMATION CONTACT: Nazih Khaouly, Aircraft Systems 
Section, AIR-673, Technical Innovation Policy Branch, Policy and 
Innovation Division, Aircraft Certification Service, Federal Aviation 
Administration, 2200 South 216th Street, Des Moines, Washington 98198; 
telephone and fax 206-231-3160; email [email protected].

SUPPLEMENTARY INFORMATION: The substance of these special conditions 
has been published in the Federal Register for public comment in 
several prior instances with no substantive comments received. 
Therefore, the FAA finds, pursuant to 14 CFR 11.38(b), that new 
comments are unlikely, and notice and comment prior to this publication 
are unnecessary. The FAA finds that, for the same reason, good cause 
exists for adopting these special conditions upon publication in the 
Federal Register.

Comments Invited

    The FAA invites 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.
    The FAA will consider all comments received by the closing date for 
comments. The FAA may change these special conditions based on comments 
received.

Background

    On April 6, 2022, Aptoz applied for a supplemental type certificate 
to install non-rechargeable lithium batteries and battery systems in 
ELTs. Aptoz intends to apply this STC to multiple transport-category 
airplanes, and may periodically amend this STC to expand its 
applicability to include additional transport-category airplane makes 
and models.

Type Certification Basis

    Under the provisions of title 14, Code of Federal Regulations (14 
CFR) 21.101, Aptoz EHF must show that the airplanes, for which they 
make application to modify by FAA STC ST00030IB, as changed, continue 
to meet the applicable provisions of the regulations listed in each 
airplane's respective type certificate or the applicable regulations in 
effect on the date of application for the change except for earlier 
amendments as agreed upon by the FAA.
    If the Administrator finds that the applicable airworthiness 
regulations (i.e., 14 CFR part 25) do not contain adequate or 
appropriate safety standards 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 airplane model 
for which they are issued. Should the applicant apply for an STC to 
modify another model included on the same type certificate to 
incorporate the same novel or unusual design feature, these special 
conditions would also apply to the other model under Sec.  21.101.
    In addition to the applicable airworthiness regulations and special 
conditions, the airplanes modified by STC no. ST00030IB 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.
    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

    The airplanes listed in the FAA STC ST00030IB approved model list 
(AML) will incorporate the following novel or unusual design feature:
    Non-rechargeable lithium batteries and battery systems installed in 
ELTs.

Discussion

    The FAA derived the current regulations governing installation of 
batteries in transport-category airplanes from Civil Air Regulations 
(CAR) 4b.625(d), as part of the recodification of CAR 4b, which 
established 14 CFR part 25 in February 1965. This recodification 
essentially reworded the CAR 4b battery requirements, which are 
currently in Sec.  25.1353(b)(1) through (4). Non-rechargeable lithium 
batteries and battery systems are novel and unusual with respect to the 
state of technology considered when these requirements were codified. 
Non-rechargeable lithium batteries and battery systems 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 introduce failure modes that require 
unique design considerations, such as provisions for thermal 
management.
    In January 2013, two independent events involving rechargeable 
lithium-ion batteries revealed unanticipated failure modes. A National 
Transportation Safety Board letter to the FAA, dated May 22, 2014, 
which is available at https://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 ELT installation demonstrated unanticipated failure 
modes. The United Kingdom's Air Accidents Investigation Branch Bulletin 
S5/2013 describes this event. These events, involving rechargeable and 
non-rechargeable lithium batteries, prompted the FAA to initiate a 
broad evaluation of these energy-storage technologies.
    On April 22, 2016, the FAA published special conditions no. 25-612-
SC in the Federal Register (81 FR 23573), applicable to Gulfstream 
Aerospace Corporation, for the Model GVI airplane. Those were the first 
special conditions the FAA issued for non-rechargeable lithium battery 
installations. In that document, the FAA explained its decision to make 
those special conditions effective on April 22, 2017, one year after 
publication in the Federal Register. In those special conditions, the 
FAA stated its intention to apply non-rechargeable lithium battery and 
battery system special conditions to design changes on other airplane 
makes and models applied for after this same date.
    Special condition no. 1 of these special conditions requires that 
each individual cell within a non-rechargeable lithium battery and 
battery system be designed to maintain safe temperatures and pressures. 
Special condition no. 2 addresses these same issues but for the entire 
battery. Special condition no. 2 requires the battery be designed to 
prevent propagation of a thermal event, such as self-sustained, 
uncontrollable increases in temperature or pressure from one cell to 
adjacent cells.
    Special condition nos. 1 and 2 are intended to ensure that the non-
rechargeable lithium battery and its cells are designed to eliminate 
the potential for uncontrollable failures. However, a certain number of 
failures will occur due to various factors beyond the control of the 
battery designer. Therefore, other special conditions are intended to 
protect the airplane and its occupants if failure occurs.
    Special conditions 3, 7, and 8 are self-explanatory.
    Special condition no. 4 makes it clear that the flammable-fluid 
fire-protection requirements of Sec.  25.863 apply to non-rechargeable 
lithium battery and battery system 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 
and

[[Page 68338]]

battery systems contain an electrolyte that is a flammable fluid.
    Special condition no. 5 requires that each non-rechargeable lithium 
battery and battery system installation not damage surrounding 
structure or adjacent systems, equipment, or electrical wiring from 
corrosive fluids or gases that may escape in such a way as to cause a 
major or more severe failure condition.
    While special condition no. 5 addresses corrosive fluids and gases, 
special condition no. 6 addresses heat. Special condition no. 6 
requires that each non-rechargeable lithium battery and battery system 
installation have provisions to prevent any hazardous effect on 
airplane structure or systems caused by the maximum amount of heat the 
battery installation can generate due to any failure of it or its 
individual cells. The means of meeting special conditions nos. 5 and 6 
may be the same, but the requirements are independent and address 
different hazards.
    These special conditions apply to all non-rechargeable lithium 
battery and battery system installations, in lieu of Sec.  
25.1353(b)(1) through (4) at amendment 25-123. Sections 25.1353(b)(1) 
through (4) at amendment 25-123 remain in effect for other battery 
installations.
    These 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 
airplane models listed on the AML of STC no. ST00030IB, available 
online at rgl.faa.gov. All models listed in the AML must be evaluated 
and determined to comply with these special conditions. Additionally, 
each new model added to the AML subsequently must also be evaluated and 
determined to comply with these special conditions.
    Should Aptoz apply at a later date for a change to STC no. 
ST00030IB, to include any other model on the AML to incorporate the 
same novel or unusual design feature, these special conditions would 
apply to that model as well.
    Should Aptoz apply at a later date for another STC to modify any 
other model included on the type certificates of the models on the STC 
no. ST00030IB AML, to incorporate the same novel or unusual design 
feature, these special conditions would also apply to that model as 
well. These special conditions are not applicable to those models for 
which applicable special conditions for rechargeable lithium batteries 
and battery systems have already been issued against the type 
certificate for that specific model.

Conclusion

    This action only affects the installation of ELTs that contain non-
rechargeable lithium batteries and battery systems for airplanes listed 
on the AML of STC no. ST00030IB. It is not a rule of general 
applicability and affects only the applicant who applied to the FAA for 
approval of these features on the airplane.

List of Subjects in 14 CFR Part 25

    Aircraft, Aviation safety, Reporting and recordkeeping 
requirements.

Authority Citation

    The authority citation for these special conditions is as follows:

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

The Special Conditions

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the following special conditions are issued as part of 
the type certification basis for the airplane modelslisted on the 
approved model list of supplemental type certificate no. ST00030IB, as 
modified by Aptoz.
    In lieu of Sec.  25.1353(b)(1) through (4) at amendment 25-123, or 
Sec.  25.1353(c)(1) through (4) at earlier amendments, each non-
rechargeable lithium battery and battery system installation must:
    1. Be designed to maintain safe cell temperatures and pressures, 
under all foreseeable operating conditions, to prevent fire and 
explosion.
    2. Be designed to prevent the occurrence of self-sustaining, 
uncontrollable 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 in 
such a way as to cause a major or more severe failure condition.
    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. Have a failure-sensing and warning system to alert the flight 
crew, in the event its failure affects safe operation of the airplane.
    8. Have a means for the flight crew or maintenance personnel to 
determine the battery charge state if the battery's function is 
required for safe operation of the airplane.

    Note: A battery system consists of the battery, battery charger, 
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 the battery system is referred to as a 
battery.


    Issued in Kansas City, Missouri, on November 8, 2022.
Patrick R. Mullen,
Manager, Technical Innovation Policy Branch, Policy and Innovation 
Division, Aircraft Certification Service.
[FR Doc. 2022-24773 Filed 11-14-22; 8:45 am]
BILLING CODE 4910-13-P