Special Conditions: AmSafe; Non-Rechargeable Lithium Battery Installations, 14164-14166 [2017-05198]

Download as PDF 14164 Proposed Rules Federal Register Vol. 82, No. 51 Friday, March 17, 2017 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. DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 25 [Docket No. FAA–2016–7852; Notice No. 25– 17–01–SC] Special Conditions: AmSafe; NonRechargeable Lithium Battery Installations Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed special conditions. AGENCY: This action proposes special conditions for a supplemental type certificate for installing an inflatable restraint system with non-rechargeable lithium batteries on seats in certain transport category airplanes. These airplanes, as modified by AmSafe, 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 a non-rechargeable lithium battery. 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 April 17, 2017. ADDRESSES: Send comments identified by docket number FAA–2016–7852 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. asabaliauskas on DSK3SPTVN1PROD with PROPOSALS SUMMARY: VerDate Sep<11>2014 19:33 Mar 16, 2017 Jkt 241001 • 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 NonRechargeable Lithium Batteries The FAA anticipates that nonrechargeable lithium batteries will be installed in most makes and models of transport category airplanes. We intend to require special conditions for certification projects involving nonrechargeable lithium battery installations to address certain safety issues until we can revise the airworthiness requirements. Applying special conditions to these installations across the range of transport category airplanes will ensure regulatory consistency. PO 00000 Frm 00001 Fmt 4702 Sfmt 4702 Typically, the FAA issues special conditions after receiving an application for type certificate approval of a novel or unusual design feature. However, the FAA has found that the presence of nonrechargeable lithium batteries in certification projects is not always immediately identifiable, since the battery itself may not be the focus of the project. Meanwhile, the inclusion of these batteries has become virtually ubiquitous on in-production transport category airplanes, which shows that there will be a need for these special conditions. Also, delaying the issuance of special conditions until after each design application is received could lead to costly certification delays. Therefore the FAA finds it necessary to issue special conditions applicable to these battery installations on particular makes and models of aircraft. 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 GVI airplane. Those were the first special conditions the FAA issued for non-rechargeable lithium battery installations. We explained in that document our decision to make those special conditions effective one year after publication in the Federal Register, and our intention for other special conditions for other makes and models to be effective on that same date or 30 days after publication, whichever is later. The effective date of special conditions no. 25–612–SC is April 22, 2017. Section 1205 of the FAA Reauthorization Act of 1996 requires the FAA to consider the extent to which Alaska is not served by transportation modes other than aviation and to establish appropriate regulatory distinctions when modifying airworthiness regulations that affect intrastate aviation in Alaska. In consideration of this requirement and the overall impact on safety, the FAA does not intend to require nonrechargeable lithium battery special conditions for design changes that only replace a 121.5 megahertz (MHz) emergency locator transmitter (ELT) with a 406 MHz ELT that meets Technical Standard Order C126b, or later revision, on transport airplanes operating only in Alaska. This will support our efforts of encouraging E:\FR\FM\17MRP1.SGM 17MRP1 Federal Register / Vol. 82, No. 51 / Friday, March 17, 2017 / Proposed Rules operators in Alaska to upgrade to a 406 MHz ELT. These ELTs provide significantly improved accuracy for lifesaving services to locate an accident site in Alaskan terrain. The FAA considers that the safety benefits from upgrading to a 406 MHz ELT for Alaskan operations will outweigh the battery fire risk. 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. asabaliauskas on DSK3SPTVN1PROD with PROPOSALS Background AmSafe is the holder of supplemental type certificate (STC) no. ST02152LA. This STC is for the installation of an inflatable restraint system with nonrechargeable lithium batteries on seats in several transport category airplanes. AmSafe periodically applies to amend this STC to expand its applicability to include additional transport category airplane makes and models. The current battery requirements in Title 14, Code of Federal Regulations (14 CFR) part 25 are inadequate for addressing an airplane with non-rechargeable lithium batteries. Type Certification Basis Under the provisions of 14 CFR 21.101, AmSafe must show that airplanes for which they make application to modify by STC no. ST02152LA, 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 § 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 any other model included on the same type certificate to incorporate the same novel or unusual design feature, these VerDate Sep<11>2014 19:33 Mar 16, 2017 Jkt 241001 special conditions would also apply to the other model under § 21.101. In addition to the applicable airworthiness regulations and special conditions, the airplanes modified by STC no. ST02152LA 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 § 11.38, and they become part of the type certification basis under § 21.101. Novel or Unusual Design Features STC no. ST02152LA is for the installation of an inflatable restraint system that incorporates nonrechargeable lithium batteries, which are a novel or unusual design feature. For the purpose of these special conditions, we refer to a battery and battery system as a battery. 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. 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 that established 14 CFR part 25 in February 1965. This recodification basically reworded the CAR 4b battery requirements, which are currently in § 25.1353(b)(1) through (4). Nonrechargeable 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 revealed 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. PO 00000 Frm 00002 Fmt 4702 Sfmt 4702 14165 On July 12, 2013, an event involving a non-rechargeable lithium battery, in an emergency locator transmitter installation, demonstrated unanticipated failure modes. The United Kingdom’s Air Accidents Investigation Branch Bulletin S5/2013 describes this event. Some 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 linereplaceable units; • Cabin safety, entertainment, and communications equipment, including emergency locator transmitters, 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 nonrechargeable 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 selfsustaining 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 nickelcadmium and lead-acid batteries, lithium 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 no. 1 of these special conditions requires that each individual cell within a nonrechargeable lithium battery be designed E:\FR\FM\17MRP1.SGM 17MRP1 asabaliauskas on DSK3SPTVN1PROD with PROPOSALS 14166 Federal Register / Vol. 82, No. 51 / Friday, March 17, 2017 / Proposed Rules to maintain safe temperatures and pressures. Proposed special condition no. 2 addresses these same issues but for the entire battery. Proposed 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. Proposed special condition nos. 1 and 2 are intended to ensure that the nonrechargeable 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. Proposed special condition nos. 3, 7, and 8 are self-explanatory. The FAA proposes special condition no. 4 to make it clear that the flammable fluid fire protection requirements of § 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 an electrolyte that is a flammable fluid. Proposed special condition no. 5 requires that each non-rechargeable lithium battery 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 proposed special condition no. 5 addresses corrosive fluids and gases, special condition no. 6 addresses heat. Proposed special condition no. 6 requires that each non-rechargeable lithium battery 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 proposed special conditions apply in lieu of § 25.1353(b)(1) through (4) at Amendment 25–123 for the installation of inflatable restraint systems with non-rechargeable lithium batteries on the seats of the subject airplanes. Sections 25.1353(b)(1) through (4) at Amendment 25–123 remain in effect for other battery installations on these airplanes. VerDate Sep<11>2014 19:33 Mar 16, 2017 Jkt 241001 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 These special conditions are applicable to the airplane models listed on the approved model list (AML) of STC no. ST02152LA, which is available at rgl.faa.gov. Should AmSafe apply at a later date for a change to STC no. ST02152LA 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 AmSafe 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. ST02152LA 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 only applicable to design changes applied for after its effective date. These special conditions are not applicable to changes to previously certified non-rechargeable lithium battery installations where the only change is either cosmetic or to relocate the installation to improve the safety of the airplane and occupants. A cosmetic change is a change in appearance only, and does not change any function or safety characteristic of the battery installation. These special conditions are also not applicable to unchanged, previously certified non-rechargeable lithium battery installations that are affected by a change in a manner that improves the safety of its installation. The FAA determined that these exclusions are in the public interest because the need to meet all of the special conditions might otherwise deter these design changes that improve safety. Conclusion This action only affects the installation of inflatable restraint systems with non-rechargeable lithium batteries on seats on the airplane models listed on the AML of STC no. ST02152LA. It is not a rule of general applicability and affects only the applicant who will apply to the FAA for approval of these features on the airplane. List of Subjects in 14 CFR Part 25 Aircraft, Aviation safety, Reporting and record keeping requirements. The authority citation for these special conditions is as follows: PO 00000 Frm 00003 Fmt 4702 Sfmt 9990 Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, 44704. The Proposed Special Conditions Accordingly, the FAA proposes the following special conditions as part of the type certification basis for airplane models listed on the approved model list of supplemental type certificate no. ST02152LA, modified by AmSafe. Non-Rechargeable Lithium Battery Installations In lieu of § 25.1353(b)(1) through (4) at Amendment 25–123, each nonrechargeable lithium battery 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 § 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 flightcrew if its failure affects safe operation of the airplane. 8. 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: 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 January 30, 2017. Michael Kaszycki, Assistant Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 2017–05198 Filed 3–16–17; 8:45 am] BILLING CODE 4910–13–P E:\FR\FM\17MRP1.SGM 17MRP1

Agencies

[Federal Register Volume 82, Number 51 (Friday, March 17, 2017)]
[Proposed Rules]
[Pages 14164-14166]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-05198]


========================================================================
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. 82, No. 51 / Friday, March 17, 2017 / 
Proposed Rules

[[Page 14164]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2016-7852; Notice No. 25-17-01-SC]


Special Conditions: AmSafe; Non-Rechargeable Lithium Battery 
Installations

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed special conditions.

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

SUMMARY: This action proposes special conditions for a supplemental 
type certificate for installing an inflatable restraint system with 
non-rechargeable lithium batteries on seats in certain transport 
category airplanes. These airplanes, as modified by AmSafe, 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 a non-rechargeable lithium 
battery. 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 April 17, 2017.

ADDRESSES: Send comments identified by docket number FAA-2016-7852 
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 most makes and models of transport category airplanes. We 
intend to require special conditions for certification projects 
involving non-rechargeable lithium battery installations to address 
certain safety issues until we can revise the airworthiness 
requirements. Applying special conditions to these installations across 
the range of transport category airplanes will ensure regulatory 
consistency.
    Typically, the FAA issues special conditions after receiving an 
application for type certificate approval of a novel or unusual design 
feature. However, the FAA has found that the presence of non-
rechargeable lithium batteries in certification projects is not always 
immediately identifiable, since the battery itself may not be the focus 
of the project. Meanwhile, the inclusion of these batteries has become 
virtually ubiquitous on in-production transport category airplanes, 
which shows that there will be a need for these special conditions. 
Also, delaying the issuance of special conditions until after each 
design application is received could lead to costly certification 
delays. Therefore the FAA finds it necessary to issue special 
conditions applicable to these battery installations on particular 
makes and models of aircraft.
    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 GVI airplane. Those were the first 
special conditions the FAA issued for non-rechargeable lithium battery 
installations. We explained in that document our decision to make those 
special conditions effective one year after publication in the Federal 
Register, and our intention for other special conditions for other 
makes and models to be effective on that same date or 30 days after 
publication, whichever is later. The effective date of special 
conditions no. 25-612-SC is April 22, 2017.
    Section 1205 of the FAA Reauthorization Act of 1996 requires the 
FAA to consider the extent to which Alaska is not served by 
transportation modes other than aviation and to establish appropriate 
regulatory distinctions when modifying airworthiness regulations that 
affect intrastate aviation in Alaska. In consideration of this 
requirement and the overall impact on safety, the FAA does not intend 
to require non-rechargeable lithium battery special conditions for 
design changes that only replace a 121.5 megahertz (MHz) emergency 
locator transmitter (ELT) with a 406 MHz ELT that meets Technical 
Standard Order C126b, or later revision, on transport airplanes 
operating only in Alaska. This will support our efforts of encouraging

[[Page 14165]]

operators in Alaska to upgrade to a 406 MHz ELT. These ELTs provide 
significantly improved accuracy for lifesaving services to locate an 
accident site in Alaskan terrain. The FAA considers that the safety 
benefits from upgrading to a 406 MHz ELT for Alaskan operations will 
outweigh the battery fire risk.

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

    AmSafe is the holder of supplemental type certificate (STC) no. 
ST02152LA. This STC is for the installation of an inflatable restraint 
system with non-rechargeable lithium batteries on seats in several 
transport category airplanes. AmSafe periodically applies to amend this 
STC to expand its applicability to include additional transport 
category airplane makes and models. The current battery requirements in 
Title 14, Code of Federal Regulations (14 CFR) part 25 are inadequate 
for addressing an airplane with non-rechargeable lithium batteries.

Type Certification Basis

    Under the provisions of 14 CFR 21.101, AmSafe must show that 
airplanes for which they make application to modify by STC no. 
ST02152LA, 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 any other 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. ST02152LA 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

    STC no. ST02152LA is for the installation of an inflatable 
restraint system that incorporates non-rechargeable lithium batteries, 
which are a novel or unusual design feature.
    For the purpose of these special conditions, we refer to a battery 
and battery system as a battery. 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.

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 that 
established 14 CFR part 25 in February 1965. This recodification 
basically reworded the CAR 4b battery requirements, which are currently 
in Sec.  25.1353(b)(1) through (4). 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 revealed 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. The United Kingdom's Air Accidents 
Investigation Branch Bulletin S5/2013 describes this event.
    Some 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;
     Cabin safety, entertainment, and communications equipment, 
including emergency locator transmitters, 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, lithium 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 no. 1 of these special conditions 
requires that each individual cell within a non-rechargeable lithium 
battery be designed

[[Page 14166]]

to maintain safe temperatures and pressures. Proposed special condition 
no. 2 addresses these same issues but for the entire battery. Proposed 
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.
    Proposed 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.
    Proposed special condition nos. 3, 7, and 8 are self-explanatory.
    The FAA proposes special condition no. 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 an electrolyte that is a flammable fluid.
    Proposed special condition no. 5 requires that each non-
rechargeable lithium battery 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 proposed special condition no. 5 addresses corrosive fluids 
and gases, special condition no. 6 addresses heat. Proposed special 
condition no. 6 requires that each non-rechargeable lithium battery 
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 proposed special conditions apply in lieu of Sec.  
25.1353(b)(1) through (4) at Amendment 25-123 for the installation of 
inflatable restraint systems with non-rechargeable lithium batteries on 
the seats of the subject airplanes. Sections 25.1353(b)(1) through (4) 
at Amendment 25-123 remain in effect for other battery installations on 
these airplanes.
    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

    These special conditions are applicable to the airplane models 
listed on the approved model list (AML) of STC no. ST02152LA, which is 
available at rgl.faa.gov. Should AmSafe apply at a later date for a 
change to STC no. ST02152LA 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 AmSafe 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. ST02152LA 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 only applicable to design changes 
applied for after its effective date.
    These special conditions are not applicable to changes to 
previously certified non-rechargeable lithium battery installations 
where the only change is either cosmetic or to relocate the 
installation to improve the safety of the airplane and occupants. A 
cosmetic change is a change in appearance only, and does not change any 
function or safety characteristic of the battery installation. These 
special conditions are also not applicable to unchanged, previously 
certified non-rechargeable lithium battery installations that are 
affected by a change in a manner that improves the safety of its 
installation. The FAA determined that these exclusions are in the 
public interest because the need to meet all of the special conditions 
might otherwise deter these design changes that improve safety.

Conclusion

    This action only affects the installation of inflatable restraint 
systems with non-rechargeable lithium batteries on seats on the 
airplane models listed on the AML of STC no. ST02152LA. It is not a 
rule of general applicability and affects only the applicant who will 
apply to the FAA for approval of these features on the airplane.

List of Subjects in 14 CFR Part 25

    Aircraft, Aviation safety, Reporting and record keeping 
requirements.

    The authority citation for these special conditions is as follows:

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

The Proposed Special Conditions

    Accordingly, the FAA proposes the following special conditions as 
part of the type certification basis for airplane models listed on the 
approved model list of supplemental type certificate no. ST02152LA, 
modified by AmSafe.

Non-Rechargeable Lithium Battery Installations

    In lieu of Sec.  25.1353(b)(1) through (4) at Amendment 25-123, 
each non-rechargeable lithium battery 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 
flightcrew if its failure affects safe operation of the airplane.
    8. 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: 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 January 30, 2017.
Michael Kaszycki,
Assistant Manager, Transport Airplane Directorate, Aircraft 
Certification Service.
[FR Doc. 2017-05198 Filed 3-16-17; 8:45 am]
BILLING CODE 4910-13-P