This section of the FEDERAL REGISTER

contains regulatory documents having general

applicability and legal effect, most of which

are keyed to and codified in the Code of

Federal Regulations, which is published under

50 titles pursuant to 44 U.S.C. 1510.

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REGISTER issue of each week.

Rules and Regulations Federal Register

55351 

Vol. 81, No. 161 

Friday, August 19, 2016 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 25 

[Docket No. FAA–2015–5758; Special 

Conditions No. 25–632–SC] 

Special Conditions: The Boeing 

Company, Boeing Model 737–8 

Airplane; Non-Rechargeable Lithium 

Battery Installations 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final special conditions. 

SUMMARY: These special conditions are 

issued for the Boeing Company (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 transportcategory airplanes. This design feature 

is associated with non-rechargeable 

lithium battery installations. 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: Effective April 22, 2017. 

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 other makes and models of 

airplanes. We have determined to 

require special conditions for all 

applications requesting nonrechargeable lithium battery 

installations, except the installations 

excluded in the Applicability section, 

until the airworthiness requirements 

can be revised to address this issue. 

Applying special conditions to these 

installations across the range of all 

transport-airplane makes and models 

ensures regulatory consistency among 

applicants. 

The FAA issued special conditions 

no. 25–612–SC to Gulfstream Aerospace 

Corporation for their GVI airplane. 

Those are the first special conditions the 

FAA issued for non-rechargeable 

lithium battery installations. We 

explained in that document our 

determination to make those special 

conditions effective one year after 

publication of those special conditions 

in the Federal Register, and our 

intention for other special conditions for 

other makes and models to be effective 

on this same date or 30 days after their 

publication, whichever is later. 

Background 

On January 27, 2012, Boeing applied 

for an amendment to type certificate no. 

A16WE to include a new Model 737–8 

airplane. The Model 737–8 airplane is a 

twin-engine, transport-category airplane 

that is a derivative of the Model 737– 

800 airplane. The Model 737–8 has a 

maximum passenger capacity of 200 and 

a maximum takeoff weight of 181,200 

lbs. 

Type Certification Basis 

Under the provisions of title 14, Code 

of Federal Regulations (14 CFR) 21.101, 

Boeing must show that the Model 737– 

8 airplane meets the applicable 

provisions of the regulations listed in 

type certificate no. 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 

special conditions. Type certificate no. 

A16WE will be updated to include a 

complete description of the certification 

basis for this airplane model. 

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 § 21.16. 

Special conditions are initially 

applicable to the airplane 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 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 § 21.101. 

In addition to the applicable 

airworthiness regulations and special 

conditions, the Model 737–8 airplane 

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 

The Boeing Model 737–8 airplane will 

incorporate non-rechargeable lithium 

batteries. 

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. 

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 re-codification 

of CAR 4b that established 14 CFR part 

25 in February 1965. We basically 

reworded the battery requirements, 

which are currently in § 25.1353(b)(1) 

through (4), from the CAR requirements. 


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55352 Federal Register / Vol. 81, No. 161 / Friday, August 19, 2016 / Rules and Regulations 

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. 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. 

Special condition 1 requires that each 

individual cell within a nonrechargeable lithium battery be designed 

to maintain safe temperatures and 

pressures. Special condition 2 addresses 

these same issues but for the entire 

battery. Special condition 2 requires 

that 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. 

Special conditions 1 and 2 are 

intended to ensure that the nonrechargeable lithium 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. 

Special conditions 3, 7, and 8 are selfexplanatory, and the FAA does not 

provide further explanation for them at 

this time. 

Special condition 4 makes it clear that 

the flammable-fluid fire-protection 

requirements of § 25.863 apply to nonrechargeable lithium battery 

installations. Section 25.863 is 

applicable to areas of the airplane that 

could be exposed to flammable fluid 

leakage from airplane systems. Nonrechargeable lithium batteries contain 

electrolyte that is a flammable fluid. 

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. 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 special conditions may be the 

same, but they are independent 

requirements addressing different 

hazards. Special condition 5 addresses 

corrosive fluids and gases, whereas 

special condition 6 addresses heat. 

These special conditions will apply to 

all non-rechargeable lithium battery 

installations in lieu of § 25.1353(b)(1) 

through (4) at Amendment 25–123. 

Sections 25.1353(b)(1) through (4) at 

Amendment 25–123 will 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. 

Discussion of Comments 

Notice of proposed special conditions 

no. 25–16–02–SC, for the Boeing 737–8 

airplane, was published in the Federal 

Register on February 11, 2016 [81 FR 

7249]. We received two substantive 

comments. 

The Aerospace Industries Association 

(AIA) provided several comments that 

were identical to their comments for 

special conditions no. 25–612–SC (81 

FR 23573), which we issued to 

Gulfstream Aerospace Corporation for 

non-rechargeable lithium battery 

installations on Gulfstream GVI 

airplanes. The FAA responded to each 

of these comments in that final special 

conditions document. We incorporated 

the same revisions into this Boeing 737– 

8 special conditions that we 

incorporated into the Gulfstream GVI 

special conditions as a result of AIA’s 

comments. 

Boeing commented that they fully 

support AIA’s comments. 

Boeing requested that the FAA 

provide adequate time before nonrechargeable lithium battery special 

conditions become effective to support 

validation activities by foreign civil 

airworthiness authorities (FCAA) and to 

not adversely impact future airplane 

deliveries by all applicants. The FAA 

considered this same comment from 

Boeing for special conditions no. 25– 

612–SC and provided a detailed 

response in that document. We 

determined the effective date for these 

Boeing 737–8 special conditions based 

on Boeing’s comment and other factors 

stated in special conditions no. 25–612– 

SC. 

Boeing commented that the FAA 

needs to clearly define the applicability 

of these special conditions. The FAA 

concurs. Boeing’s comment is similar to 


jstallworth on DSK7TPTVN1PROD with RULES
Federal Register / Vol. 81, No. 161 / Friday, August 19, 2016 / Rules and Regulations 55353 

their comment on special conditions no. 

25–612–SC. We provided a detailed 

response in special conditions no. 25– 

612–SC and have now clearly defined 

the applicability for these Boeing 737– 

8 special conditions. One aspect of 

Boeing’s comment that we did not 

address in special conditions no. 25– 

612–SC is that some design changes 

may not change a lithium battery 

installation but affect it, which results 

in these special conditions being 

applicable. For example, adding a heat 

source next to a lithium battery can 

increase its possibility of entering into 

thermal runaway. Lithium battery 

installations affected by design changes 

must meet these special conditions. 

Some examples of changes that affect 

lithium battery installations are those 

that: 

• Increase the temperatures or 

pressures in a battery, 

• Increase the electrical load on a 

battery, 

• Increase potential for imbalance 

between battery cells, 

• Modify protective circuitry for a 

lithium battery, 

• Increase the airplane level risk due 

to the location of an existing lithium 

battery. An example is installation of a 

new oxygen line next to an existing part 

that has a lithium battery. The airplane 

level risk may increase due to the 

potential hazard of a lithium battery fire 

in the proximity of oxygen. 

The FAA has determined that 

‘‘uncontrolled’’ in special condition 2 

should be ‘‘uncontrollable’’ to more 

accurately describe the concern. This 

revision does not change the intended 

meaning of this special condition. 

Except as discussed above, the special 

conditions are adopted as proposed. 

Applicability 

As discussed above, these special 

conditions are applicable to the 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. 

These special conditions are only 

applicable to design changes applied for 

after the effective date of the special 

conditions. The existing airplane fleet 

and follow-on deliveries of airplanes 

with previously certified nonrechargeable lithium battery 

installations are not affected. 

These special conditions are not 

applicable to previously certified nonrechargeable lithium battery 

installations where the only change is 

either cosmetic or relocating the 

installation to improve the safety of the 

airplane and occupants. The FAA 

determined that this exclusion is in the 

public interest because the need to meet 

all of the special conditions might 

otherwise deter such design changes 

that involve relocating batteries. A 

cosmetic change is a change in 

appearance only, and does not change 

any function or safety characteristic of 

the battery installation. 

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 recordkeeping requirements. 

■ The authority citation for these 

special conditions is as follows: 

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

44702, 44704. 

The Special Conditions 

Accordingly, the following special 

conditions are part of the type 

certification basis for the Boeing Model 

737–8 airplane. 

Non-Rechargeable Lithium Battery 

Installations 

In lieu of § 25.1353(b)(1) through 

(b)(4) at Amendment 25–123, each nonrechargeable 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 selfsustaining, 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 August 

12, 2016. 

Michael Kaszycki, 

Assistant Manager, Transport Airplane 

Directorate, Aircraft Certification Service. 

[FR Doc. 2016–19856 Filed 8–18–16; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2015–3986; Directorate 

Identifier 2015–NM–057–AD; Amendment 

39–18613; AD 2016–16–15] 

RIN 2120–AA64 

Airworthiness Directives; Bombardier, 

Inc. Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final rule. 

SUMMARY: We are adopting a new 

airworthiness directive (AD) for certain 

Bombardier, Inc. Model DHC–8–400, 

–401, and –402 airplanes. This AD was 

prompted by reports of chafing damage 

due to insufficient clearance on the 

main landing gear (MLG) stabilizer 

brace, the nacelle A-frame structure, and 

the adjacent electrical wiring harnesses. 

An insufficient fillet radius may also 

exist on certain airplanes. This AD 

requires, depending on airplane 

configuration, an inspection of the 

nacelle A-frame structure for 

insufficient fillet radius; an inspection 

for cracking of affected structure, and 

rework or repair if necessary, and 

rework of the nacelle A-frame structure; 

repetitive inspections of the nacelle Aframe structure and the MLG stabilizer 

brace for insufficient clearance and 

damage, and repair if necessary, and 

rework of the nacelle A-frame structure, 

which would terminate the repetitive 

inspections; installation of new stop 

brackets and a shim on each MLG 

stabilizer brace assembly; and rework of 

the electrical wiring harnesses in the 

nacelle area. We are issuing this AD to 


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