Special Conditions: Cessna Aircraft Company, Models 208 and 208B, Caravan Airplanes; As Modified by Peregrine; Installation of Rechargeable Lithium Battery, 30164-30166 [2016-11502]
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Federal Register / Vol. 81, No. 94 / Monday, May 16, 2016 / Rules and Regulations
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 23
[Docket No. FAA–2016–6567; Special
Conditions No. 23–274–SC]
Special Conditions: Cessna Aircraft
Company, Models 208 and 208B,
Caravan Airplanes; As Modified by
Peregrine; Installation of Rechargeable
Lithium Battery
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions; request
for comments.
AGENCY:
These special conditions are
issued for the Cessna Aircraft Company,
Models 208 and 208B Caravan
airplanes. This airplane, as modified by
Peregrine, will have a novel or unusual
design feature associated with the use of
a replacement option of a lithium
battery instead of nickel-cadmium (NiCd) and lead-acid rechargeable batteries.
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: The effective date of these
special conditions is May 16, 2016. We
must receive your comments by June 15,
2016.
ADDRESSES: Send comments identified
by docket number FAA–2016–6567
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 of 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 https://regulations.gov, including any
personal information the commenter
provides. Using the search function of
the docket Web site, anyone can find
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SUMMARY:
VerDate Sep<11>2014
14:36 May 13, 2016
Jkt 238001
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 https://DocketsInfo.dot.gov.
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 the 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:
Ruth Hirt, Federal Aviation
Administration, Small Airplane
Directorate, Aircraft Certification
Service, ACE–114, 901 Locust, Room
301, Kansas City, MO 64106; telephone
(816) 329–4108, facsimile (816) 329–
4090.
SUPPLEMENTARY INFORMATION:
The FAA has determined, in
accordance with 5 U.S.C. 553(b)(3)(B)
and 553(d)(3), that notice and
opportunity for prior public comment
hereon are unnecessary because the
substance of this special condition has
been subject to the public comment
process in several prior instances with
no substantive comments received. The
FAA, therefore, finds that good cause
exists for making these special
conditions effective upon issuance.
Special
condition
number
23–269–SC 1 ..
23–236–SC 2 ..
23–249–SC 3 ..
Company/airplane model
Honda Aircraft Company
Model HA–420.
Cessna Aircraft Company
Model 525C (CJ4).
Cessna Aircraft Company
Model 525 Citation.
1 https://rgl.faa.gov/Regulatory_and_
Guidance_Library/rgSC.nsf/0/
673E1A183F208FF186257EC90042DD79?
OpenDocument&Highlight=lithium
%20ion%20battery%20installation.
2 https://rgl.faa.gov/Regulatory_and_
Guidance_Library/rgSC.nsf/0/
83608DAA4B3E5D7A8625761D004EDE7B?
OpenDocument&Highlight=lithium
%20ion%20battery%20installation.
3 https://rgl.faa.gov/Regulatory_and_
Guidance_Library/rgSC.nsf/0/
BBFDE3920E2AFB1D862577700046E311?
OpenDocument&Highlight=lithium
%20ion%20battery%20installation.
Comments Invited
We invite interested people to take
part in this rulemaking by sending
written comments, data, or views. The
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most helpful comments reference a
specific portion of the special
conditions, explain the reason for any
recommended change, and include
supporting data. We ask that you send
us two copies of written comments.
We will consider all comments we
receive on or before the closing date for
comments. We will consider comments
filed late if it is possible to do so
without incurring expense or delay. We
may change these special conditions
based on the comments we receive.
Background
On March 25, 2015, Peregrine applied
for a supplemental type certificate (STC)
to install a rechargeable lithium battery
on the Cessna Models 208 and 208B
Caravan airplanes. Both the 208 and
208B are normal category airplanes,
powered by a single-turbine engine that
drives an aircraft propeller, with
passenger seating up to eleven (11) and
a maximum takeoff weight of 8,000 and
8,750 pounds respectively.
The current regulatory requirements
for part 23 airplanes do not contain
adequate requirements for the
application of rechargeable lithium
batteries in airborne applications. This
type of battery possesses certain failure
and operational characteristics with
maintenance requirements that differ
significantly from that of the Ni-Cd and
lead-acid rechargeable batteries
currently approved in other normal,
utility, acrobatic, and commuter
category airplanes. Therefore, the FAA
is proposing this special condition to
address (1) all characteristics of the
rechargeable lithium batteries and their
installation that could affect safe
operation of the modified 208 and 208B
airplanes, and (2) appropriate
Instructions for Continued
Airworthiness (ICAW) that include
maintenance requirements to ensure the
availability of electrical power from the
batteries when needed.
Type Certification Basis
Under the provisions of Title 14, Code
of Federal Regulations (CFR) 21.101,
Peregrine must show that the 208 and
208B airplanes, as changed, continue to
meet the applicable provisions of the
regulations incorporated by reference in
Type Certificate Data Sheet No. A37CE,
or the applicable regulations in effect on
the date of application for the change.
If the Administrator finds that the
applicable airworthiness regulations
(i.e., 14 CFR part 23) do not contain
adequate or appropriate safety standards
for the 208 and 208B airplanes because
of a novel or unusual design feature,
special conditions are prescribed under
the provisions of § 21.16.
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Federal Register / Vol. 81, No. 94 / Monday, May 16, 2016 / Rules and Regulations
In addition to the applicable
airworthiness regulations and special
conditions, the 208 and 208B airplanes
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 § 11.19, under § 11.38 and
they become part of the type
certification basis under § 21.101.
Special conditions are initially
applicable to the models 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 § 21.101.
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Novel or Unusual Design Features
The Cessna Models 208 and 208B
airplanes will incorporate the following
novel or unusual design features:
The installation of a rechargeable
lithium battery as a main or engine start
aircraft battery.
Discussion
The applicable part 23 airworthiness
regulations governing the installation of
batteries in general aviation airplanes,
including § 23.1353, were derived from
Civil Air Regulations (CAR) 3 as part of
the recodification that established 14
CFR part 23. The battery requirements,
which are identified in § 23.1353, were
a rewording of the CAR requirements
that did not add any substantive
technical requirements. An increase in
incidents involving battery fires and
failures that accompanied the increased
use of Ni-Cd batteries in aircraft resulted
in rulemaking activities on the battery
requirements for transport category
airplanes. These regulations were
incorporated into § 23.1353(f) and (g),
which apply only to Ni-Cd battery
installations.
The introduction of lithium batteries
into aircraft raises some concern about
associated battery or cell monitoring
systems and the impact to the electrical
system when monitoring components
fail. Associated battery or cell
monitoring systems (e.g., temperature,
state of charge, etc.) should be evaluated
with respect the expected extremes in
the aircraft operating environment.
Lithium batteries typically have
different electrical impedance
characteristics than Ni-Cd or lead-acid
batteries. Peregrine needs to evaluate
other components of the aircraft
electrical system with respect to these
characteristics.
Presently, there is limited experience
with use of rechargeable lithium
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batteries and rechargeable lithium
battery systems in applications
involving commercial aviation.
However, other users of this technology,
ranging from personal computers,
wireless telephone manufacturers to the
electric vehicle industry, have noted
safety problems with rechargeable
lithium batteries. These problems
include overcharging, over-discharging,
flammability of cell components, cell
internal defects, and during exposure to
extreme temperatures that are described
in the following paragraphs.
1. Overcharging: In general,
rechargeable lithium batteries are
significantly more susceptible to
internal failures that can result in selfsustaining increases in temperature and
pressure (e.g., thermal runaway) than
their Ni-Cd or lead-acid counterparts.
This is especially true for overcharging
which causes heating and
destabilization of the components of the
cell, leading to the formation (by
plating) of highly unstable metallic
lithium. The metallic lithium can ignite,
resulting in a self-sustaining fire or
explosion. Finally, the severity of
thermal runaway due to overcharging
increases with increasing battery
capacity due to the higher amount of
electrolyte in large batteries.
2. Over-discharging: Discharge of
some types of rechargeable lithium
battery cells beyond the manufacturer’s
recommended specification can cause
corrosion of the electrodes of the cell,
resulting in loss of battery capacity that
cannot be reversed by recharging. This
loss of capacity may not be detected by
the simple voltage measurements
commonly available to flight crews as a
means of checking battery status—a
problem shared with Ni-Cd batteries. In
addition, over-discharging has the
potential to lead to an unsafe condition
(creation of dendrites that could result
in internal short circuit during the
recharging cycle).
3. Flammability of Cell Components:
Unlike Ni-Cd and lead-acid batteries,
some types of rechargeable lithium
batteries use liquid electrolytes that are
flammable. The electrolyte can serve as
a source of fuel for an external fire, if
there is a breach of the battery
container.
4. Cell Internal Defects: The
rechargeable lithium batteries and
rechargeable battery systems have a
history of undetected cell internal
defects. These defects may or may not
be detected during normal operational
evaluation, test and validation. This
may lead to an unsafe condition during
in service operation.
5. Extreme Temperatures: Exposure to
an extreme temperature environment
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30165
has the potential to create major
hazards. Care must be taken to ensure
that the lithium battery remains within
the manufacturer’s recommended
specification.
These problems experienced by users
of lithium batteries raise concern about
the use of lithium batteries in aviation.
The intent of the proposed special
condition is to establish appropriate
airworthiness standards for lithium
battery installations in the 208 and 208B
airplanes and to ensure, as required by
§§ 23.1309 and 23.601, that these battery
installations are not hazardous or
unreliable.
Applicability
The special conditions are applicable
to the 208 and 208B airplanes. Should
Peregrine apply at a later date for an
STC to modify any other model
included on Type Certificate No. A37CE
to incorporate the same novel or
unusual design feature, the special
conditions would apply to that model as
well.
Conclusion
This action affects only certain novel
or unusual design features on the 208
and 208B airplanes. 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.
The substance of these special
conditions has been subjected to the
notice and comment period in several
prior instances and has been derived
without substantive change from those
previously issued. It is unlikely that
prior public comment would result in a
significant change from the subject
contained herein. Therefore, notice and
opportunity for prior public comment
hereon are unnecessary and the FAA
finds good cause, in accordance with 5
U.S.C. 553(b)(3)(B) and 553(d)(3),
making these special conditions
effective upon issuance. The FAA is
requesting comments to allow interested
persons to submit views that may not
have been submitted in response to the
prior opportunities for comment
described above.
List of Subjects in 14 CFR Part 23
Aircraft, Aviation safety, Signs and
symbols.
Citation
The authority citation for these
special conditions is as follows:
■
Authority: 49 U.S.C. 106(g), 40113 and
44701; 14 CFR 21.16 and 21.101; and 14 CFR
11.38 and 11.19.
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Federal Register / Vol. 81, No. 94 / Monday, May 16, 2016 / Rules and Regulations
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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 Cessna Aircraft Company, 208
and 208B Caravan airplanes modified by
Peregrine.
1. Installation of Lithium Battery
The FAA states in this Notice that the
following special conditions be applied
to lithium battery installations on the
208 and 208B airplanes in lieu of the
requirements § 23.1353(a)(b)(c)(d)(e),
amendment 49.
Lithium battery installations on the
208 and 208B airplanes must be
designed and installed as follows:
a. Safe cell temperatures and
pressures must be maintained during
any probable charging or discharging
condition, or during any failure of the
charging or battery monitoring system
not shown to be extremely remote. The
lithium battery installation must be
designed to preclude explosion or fire in
the event of those failures.
b. Lithium batteries must be designed
to preclude the occurrence of selfsustaining, uncontrolled increases in
temperature or pressure.
c. No explosive or toxic gasses
emitted by any lithium battery in
normal operation or as the result of any
failure of the battery charging or
monitoring system, or battery
installation not shown to be extremely
remote, may accumulate in hazardous
quantities within the airplane.
d. Lithium batteries that contain
flammable fluids must comply with the
flammable fluid fire protection
requirements of 14 CFR 23.863(a)
through (d).
e. No corrosive fluids or gases that
may escape from any lithium battery
may damage airplane structure or
essential equipment.
f. Each lithium battery installation
must have provisions to prevent any
hazardous effect on structure or
essential systems that may be caused by
the maximum amount of heat the
battery can generate during a short
circuit of the battery or of its individual
cells.
g. Lithium battery installations must
have—
(1) A system to control the charging
rate of the battery automatically to
prevent battery overheating or
overcharging, or
(2) A battery temperature sensing and
over-temperature warning system with a
means for automatically disconnecting
the battery from its charging source in
the event of an over-temperature
condition or,
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14:36 May 13, 2016
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(3) A battery failure sensing and
warning system with a means for
automatically disconnecting the battery
from its charging source in the event of
battery failure.
h. Any lithium battery installation
functionally required for safe operation
of the airplane, must incorporate a
monitoring and warning feature that
will provide an indication to the
appropriate flight crewmembers,
whenever the capacity and state of
charge of the batteries have fallen below
levels considered acceptable for
dispatch of the airplane.
i. The ICAW must contain
recommended manufacturer’s
maintenance and inspection
requirements to ensure that batteries,
including single cells, meet a
functionally safe level essential to the
aircraft’s continued airworthiness.
(1) The ICAW must contain operating
instructions and equipment limitations
in an installation maintenance manual.
(2) The ICAW must contain
installation procedures and limitations
in a maintenance manual, sufficient to
ensure that cells or batteries, when
installed according to the installation
procedures, still meet safety functional
levels essential to the aircraft’s
continued airworthiness. The
limitations must identify any unique
aspects of the installation.
(3) The ICAW must contain corrective
maintenance procedures to check
battery capacity at manufacturer’s
recommended inspection intervals.
(4) The ICAW must contain scheduled
servicing information to replace
batteries at manufacturer’s
recommended replacement time.
(5) The ICAW must contain
maintenance and inspection
requirements how to check visually for
battery and charger degradation.
j. Batteries in a rotating stock (spares)
that have degraded charge retention
capability or other damage due to
prolonged storage must be checked at
manufacturer’s recommended
inspection intervals.
k. If the lithium battery application
contains software and/or complex
hardware, in accordance with AC 20–
115 1 and AC 20–152,2 they should be
developed to the standards of DO–178
for software and DO–254 for complex
hardware.
Compliance with the requirements of
this Special Condition must be shown
1 https://rgl.faa.gov/Regulatory_and_Guidance_
Library/rgAdvisoryCircular.nsf/0/
E35FBC0060E2159186257BBE00719FB3?Open
Document&Highlight=ac%2020-115b.
2 https://rgl.faa.gov/Regulatory_and_Guidance_
Library/rgAdvisoryCircular.nsf/0/
6D4AE0BF1BDE3579862570360055D119?Open
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by test or analysis, with the concurrence
of the Wichita Aircraft Certification
Office.
Issued in Kansas City, Missouri on May 9,
2016.
Pat Mullen,
Acting Manager, Small Airplane Directorate,
Aircraft Certification Service.
[FR Doc. 2016–11502 Filed 5–13–16; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2015–2462; Directorate
Identifier 2014–NM–224–AD; Amendment
39–18515; AD 2016–10–04]
RIN 2120–AA64
Airworthiness Directives; The Boeing
Company Airplanes
Federal Aviation
Administration (FAA), DOT.
ACTION: Final rule.
AGENCY:
We are adopting a new
airworthiness directive (AD) for certain
The Boeing Company Model 737–100,
–200, –200C, –300, –400, and –500
series airplanes. This AD was prompted
by reports of cracked antenna support
channels, skin cracking underneath the
number 2 very high frequency (VHF)
antenna, and cracking in the frames
attached to the internal support
structure. This AD requires repetitive
inspections to determine the condition
of the skin and the internal support
structure, and follow-on actions
including corrective action as necessary.
We are issuing this AD to detect and
correct skin cracking of the fuselage.
Such cracking could result in separation
of the number 2 VHF antenna from the
airplane and rapid depressurization of
the cabin.
DATES: This AD is effective June 20,
2016.
The Director of the Federal Register
approved the incorporation by reference
of a certain publication listed in this AD
as of June 20, 2016.
ADDRESSES: For service information
identified in this final rule, contact
Boeing Commercial Airplanes,
Attention: Data & Services Management,
P.O. Box 3707, MC 2H–65, Seattle, WA
98124–2207; telephone 206–544–5000,
extension 1; fax 206–766–5680; Internet
https://www.myboeingfleet.com. You
may view this referenced service
information at the FAA, Transport
Airplane Directorate, 1601 Lind Avenue
SW., Renton, WA. For information on
SUMMARY:
E:\FR\FM\16MYR1.SGM
16MYR1
]]>Agencies
[Federal Register Volume 81, Number 94 (Monday, May 16, 2016)]
[Rules and Regulations]
[Pages 30164-30166]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-11502]
[[Page 30164]]
=======================================================================
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 23
[Docket No. FAA-2016-6567; Special Conditions No. 23-274-SC]
Special Conditions: Cessna Aircraft Company, Models 208 and 208B,
Caravan Airplanes; As Modified by Peregrine; Installation of
Rechargeable Lithium Battery
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions; request for comments.
-----------------------------------------------------------------------
SUMMARY: These special conditions are issued for the Cessna Aircraft
Company, Models 208 and 208B Caravan airplanes. This airplane, as
modified by Peregrine, will have a novel or unusual design feature
associated with the use of a replacement option of a lithium battery
instead of nickel-cadmium (Ni-Cd) and lead-acid rechargeable batteries.
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: The effective date of these special conditions is May 16, 2016.
We must receive your comments by June 15, 2016.
ADDRESSES: Send comments identified by docket number FAA-2016-6567
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 of 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 https://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 https://DocketsInfo.dot.gov.
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 the 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: Ruth Hirt, Federal Aviation
Administration, Small Airplane Directorate, Aircraft Certification
Service, ACE-114, 901 Locust, Room 301, Kansas City, MO 64106;
telephone (816) 329-4108, facsimile (816) 329-4090.
SUPPLEMENTARY INFORMATION:
The FAA has determined, in accordance with 5 U.S.C. 553(b)(3)(B)
and 553(d)(3), that notice and opportunity for prior public comment
hereon are unnecessary because the substance of this special condition
has been subject to the public comment process in several prior
instances with no substantive comments received. The FAA, therefore,
finds that good cause exists for making these special conditions
effective upon issuance.
------------------------------------------------------------------------
Special condition number Company/airplane model
------------------------------------------------------------------------
23-269-SC \1\.......................... Honda Aircraft Company Model HA-
420.
23-236-SC \2\.......................... Cessna Aircraft Company Model
525C (CJ4).
23-249-SC \3\.......................... Cessna Aircraft Company Model
525 Citation.
------------------------------------------------------------------------
\1\ https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgSC.nsf/0/673E1A183F208FF186257EC90042DD79?OpenDocument&Highlight=lithium%20ion%20battery%20installation.
\2\ https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgSC.nsf/0/83608DAA4B3E5D7A8625761D004EDE7B?OpenDocument&Highlight=lithium%20ion%20battery%20installation.
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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 ask
that you send us two copies of written comments.
We will consider all comments we receive on or before the closing
date for comments. We will consider comments filed late if it is
possible to do so without incurring expense or delay. We may change
these special conditions based on the comments we receive.
Background
On March 25, 2015, Peregrine applied for a supplemental type
certificate (STC) to install a rechargeable lithium battery on the
Cessna Models 208 and 208B Caravan airplanes. Both the 208 and 208B are
normal category airplanes, powered by a single-turbine engine that
drives an aircraft propeller, with passenger seating up to eleven (11)
and a maximum takeoff weight of 8,000 and 8,750 pounds respectively.
The current regulatory requirements for part 23 airplanes do not
contain adequate requirements for the application of rechargeable
lithium batteries in airborne applications. This type of battery
possesses certain failure and operational characteristics with
maintenance requirements that differ significantly from that of the Ni-
Cd and lead-acid rechargeable batteries currently approved in other
normal, utility, acrobatic, and commuter category airplanes. Therefore,
the FAA is proposing this special condition to address (1) all
characteristics of the rechargeable lithium batteries and their
installation that could affect safe operation of the modified 208 and
208B airplanes, and (2) appropriate Instructions for Continued
Airworthiness (ICAW) that include maintenance requirements to ensure
the availability of electrical power from the batteries when needed.
Type Certification Basis
Under the provisions of Title 14, Code of Federal Regulations (CFR)
21.101, Peregrine must show that the 208 and 208B airplanes, as
changed, continue to meet the applicable provisions of the regulations
incorporated by reference in Type Certificate Data Sheet No. A37CE, or
the applicable regulations in effect on the date of application for the
change.
If the Administrator finds that the applicable airworthiness
regulations (i.e., 14 CFR part 23) do not contain adequate or
appropriate safety standards for the 208 and 208B airplanes because of
a novel or unusual design feature, special conditions are prescribed
under the provisions of Sec. 21.16.
[[Page 30165]]
In addition to the applicable airworthiness regulations and special
conditions, the 208 and 208B airplanes 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 Sec. 11.19, under
Sec. 11.38 and they become part of the type certification basis under
Sec. 21.101.
Special conditions are initially applicable to the models 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.
Novel or Unusual Design Features
The Cessna Models 208 and 208B airplanes will incorporate the
following novel or unusual design features:
The installation of a rechargeable lithium battery as a main or
engine start aircraft battery.
Discussion
The applicable part 23 airworthiness regulations governing the
installation of batteries in general aviation airplanes, including
Sec. 23.1353, were derived from Civil Air Regulations (CAR) 3 as part
of the recodification that established 14 CFR part 23. The battery
requirements, which are identified in Sec. 23.1353, were a rewording
of the CAR requirements that did not add any substantive technical
requirements. An increase in incidents involving battery fires and
failures that accompanied the increased use of Ni-Cd batteries in
aircraft resulted in rulemaking activities on the battery requirements
for transport category airplanes. These regulations were incorporated
into Sec. 23.1353(f) and (g), which apply only to Ni-Cd battery
installations.
The introduction of lithium batteries into aircraft raises some
concern about associated battery or cell monitoring systems and the
impact to the electrical system when monitoring components fail.
Associated battery or cell monitoring systems (e.g., temperature, state
of charge, etc.) should be evaluated with respect the expected extremes
in the aircraft operating environment.
Lithium batteries typically have different electrical impedance
characteristics than Ni-Cd or lead-acid batteries. Peregrine needs to
evaluate other components of the aircraft electrical system with
respect to these characteristics.
Presently, there is limited experience with use of rechargeable
lithium batteries and rechargeable lithium battery systems in
applications involving commercial aviation. However, other users of
this technology, ranging from personal computers, wireless telephone
manufacturers to the electric vehicle industry, have noted safety
problems with rechargeable lithium batteries. These problems include
overcharging, over-discharging, flammability of cell components, cell
internal defects, and during exposure to extreme temperatures that are
described in the following paragraphs.
1. Overcharging: In general, rechargeable lithium batteries are
significantly more susceptible to internal failures that can result in
self-sustaining increases in temperature and pressure (e.g., thermal
runaway) than their Ni-Cd or lead-acid counterparts. This is especially
true for overcharging which causes heating and destabilization of the
components of the cell, leading to the formation (by plating) of highly
unstable metallic lithium. The metallic lithium can ignite, resulting
in a self-sustaining fire or explosion. Finally, the severity of
thermal runaway due to overcharging increases with increasing battery
capacity due to the higher amount of electrolyte in large batteries.
2. Over-discharging: Discharge of some types of rechargeable
lithium battery cells beyond the manufacturer's recommended
specification can cause corrosion of the electrodes of the cell,
resulting in loss of battery capacity that cannot be reversed by
recharging. This loss of capacity may not be detected by the simple
voltage measurements commonly available to flight crews as a means of
checking battery status--a problem shared with Ni-Cd batteries. In
addition, over-discharging has the potential to lead to an unsafe
condition (creation of dendrites that could result in internal short
circuit during the recharging cycle).
3. Flammability of Cell Components: Unlike Ni-Cd and lead-acid
batteries, some types of rechargeable lithium batteries use liquid
electrolytes that are flammable. The electrolyte can serve as a source
of fuel for an external fire, if there is a breach of the battery
container.
4. Cell Internal Defects: The rechargeable lithium batteries and
rechargeable battery systems have a history of undetected cell internal
defects. These defects may or may not be detected during normal
operational evaluation, test and validation. This may lead to an unsafe
condition during in service operation.
5. Extreme Temperatures: Exposure to an extreme temperature
environment has the potential to create major hazards. Care must be
taken to ensure that the lithium battery remains within the
manufacturer's recommended specification.
These problems experienced by users of lithium batteries raise
concern about the use of lithium batteries in aviation. The intent of
the proposed special condition is to establish appropriate
airworthiness standards for lithium battery installations in the 208
and 208B airplanes and to ensure, as required by Sec. Sec. 23.1309 and
23.601, that these battery installations are not hazardous or
unreliable.
Applicability
The special conditions are applicable to the 208 and 208B
airplanes. Should Peregrine apply at a later date for an STC to modify
any other model included on Type Certificate No. A37CE to incorporate
the same novel or unusual design feature, the special conditions would
apply to that model as well.
Conclusion
This action affects only certain novel or unusual design features
on the 208 and 208B airplanes. 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.
The substance of these special conditions has been subjected to the
notice and comment period in several prior instances and has been
derived without substantive change from those previously issued. It is
unlikely that prior public comment would result in a significant change
from the subject contained herein. Therefore, notice and opportunity
for prior public comment hereon are unnecessary and the FAA finds good
cause, in accordance with 5 U.S.C. 553(b)(3)(B) and 553(d)(3), making
these special conditions effective upon issuance. The FAA is requesting
comments to allow interested persons to submit views that may not have
been submitted in response to the prior opportunities for comment
described above.
List of Subjects in 14 CFR Part 23
Aircraft, Aviation safety, Signs and symbols.
Citation
0
The authority citation for these special conditions is as follows:
Authority: 49 U.S.C. 106(g), 40113 and 44701; 14 CFR 21.16 and
21.101; and 14 CFR 11.38 and 11.19.
[[Page 30166]]
The Special Conditions
0
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 Cessna Aircraft Company, 208 and 208B
Caravan airplanes modified by Peregrine.
1. Installation of Lithium Battery
The FAA states in this Notice that the following special conditions
be applied to lithium battery installations on the 208 and 208B
airplanes in lieu of the requirements Sec. 23.1353(a)(b)(c)(d)(e),
amendment 49.
Lithium battery installations on the 208 and 208B airplanes must be
designed and installed as follows:
a. Safe cell temperatures and pressures must be maintained during
any probable charging or discharging condition, or during any failure
of the charging or battery monitoring system not shown to be extremely
remote. The lithium battery installation must be designed to preclude
explosion or fire in the event of those failures.
b. Lithium batteries must be designed to preclude the occurrence of
self-sustaining, uncontrolled increases in temperature or pressure.
c. No explosive or toxic gasses emitted by any lithium battery in
normal operation or as the result of any failure of the battery
charging or monitoring system, or battery installation not shown to be
extremely remote, may accumulate in hazardous quantities within the
airplane.
d. Lithium batteries that contain flammable fluids must comply with
the flammable fluid fire protection requirements of 14 CFR 23.863(a)
through (d).
e. No corrosive fluids or gases that may escape from any lithium
battery may damage airplane structure or essential equipment.
f. Each lithium battery installation must have provisions to
prevent any hazardous effect on structure or essential systems that may
be caused by the maximum amount of heat the battery can generate during
a short circuit of the battery or of its individual cells.
g. Lithium battery installations must have--
(1) A system to control the charging rate of the battery
automatically to prevent battery overheating or overcharging, or
(2) A battery temperature sensing and over-temperature warning
system with a means for automatically disconnecting the battery from
its charging source in the event of an over-temperature condition or,
(3) A battery failure sensing and warning system with a means for
automatically disconnecting the battery from its charging source in the
event of battery failure.
h. Any lithium battery installation functionally required for safe
operation of the airplane, must incorporate a monitoring and warning
feature that will provide an indication to the appropriate flight
crewmembers, whenever the capacity and state of charge of the batteries
have fallen below levels considered acceptable for dispatch of the
airplane.
i. The ICAW must contain recommended manufacturer's maintenance and
inspection requirements to ensure that batteries, including single
cells, meet a functionally safe level essential to the aircraft's
continued airworthiness.
(1) The ICAW must contain operating instructions and equipment
limitations in an installation maintenance manual.
(2) The ICAW must contain installation procedures and limitations
in a maintenance manual, sufficient to ensure that cells or batteries,
when installed according to the installation procedures, still meet
safety functional levels essential to the aircraft's continued
airworthiness. The limitations must identify any unique aspects of the
installation.
(3) The ICAW must contain corrective maintenance procedures to
check battery capacity at manufacturer's recommended inspection
intervals.
(4) The ICAW must contain scheduled servicing information to
replace batteries at manufacturer's recommended replacement time.
(5) The ICAW must contain maintenance and inspection requirements
how to check visually for battery and charger degradation.
j. Batteries in a rotating stock (spares) that have degraded charge
retention capability or other damage due to prolonged storage must be
checked at manufacturer's recommended inspection intervals.
k. If the lithium battery application contains software and/or
complex hardware, in accordance with AC 20-115 \1\ and AC 20-152,\2\
they should be developed to the standards of DO-178 for software and
DO-254 for complex hardware.
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\1\ https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/0/E35FBC0060E2159186257BBE00719FB3?OpenDocument&Highlight=ac%2020-115b.
\2\ https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/0/6D4AE0BF1BDE3579862570360055D119?OpenDocument&Highlight=ac%2020-152.
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Compliance with the requirements of this Special Condition must be
shown by test or analysis, with the concurrence of the Wichita Aircraft
Certification Office.
Issued in Kansas City, Missouri on May 9, 2016.
Pat Mullen,
Acting Manager, Small Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2016-11502 Filed 5-13-16; 8:45 am]
BILLING CODE 4910-13-P
