[Federal Register Volume 74, Number 71 (Wednesday, April 15, 2009)]
[Rules and Regulations]
[Pages 17382-17384]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E9-8582]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 23

[Docket No. CE291; Special Conditions No. 23-231-SC]


Special Conditions: Spectrum Aeronautical, LLC Model 40; Lithium 
Polymer Battery Installation

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final special conditions.

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SUMMARY: These special conditions are issued for the Spectrum 
Aeronautical, LLC Model 40 (S-40) airplane. This airplane will have a 
novel or unusual design feature associated with the installation of 
lithium polymer (Li-Poly) batteries for emergency, main, and auxiliary 
power unit (APU) applications. 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 Date: April 7, 2009.

FOR FURTHER INFORMATION CONTACT: Jim Brady, Aerospace Engineer, 
Standards

[[Page 17383]]

Office (ACE-111), Small Airplane Directorate, Aircraft Certification 
Service, Federal Aviation Administration, 901 Locust, Room 301, Kansas 
City, Missouri 64106; telephone (816) 329-4132.

SUPPLEMENTARY INFORMATION:

Background

    On November 21, 2007, Spectrum Aeronautical, LLC applied for a type 
certificate for their new model 40 airplane. The model 40 (S-40) 
airplane is a 2+9 (pilots + passengers) conventionally configured low 
wing normal category twin-engine jet airplane manufactured primarily 
from advanced carbon fiber composite materials. The model S-40 is 
designed to be certified for a single pilot operation for day, night, 
VFR, IFR and flight into known icing operations at altitudes up to 
45,000 feet. The company will show compliance with Reduced Vertical 
Separation Minimums (RVSM) requirements. Spectrum proposes to utilize 
lithium polymer (Li-Poly) batteries for emergency, main, and auxiliary 
power unit (APU) on the model S-40 airplane.

Type Certification Basis

    Under the provisions of 14 CFR part 21, Sec.  21.17, Spectrum 
Aeronautical, LLC must show that the model S-40 meets the applicable 
provisions of part 23, as amended by Amendments 23-1 through 23-57 
thereto.
    In addition, the certification basis includes certain special 
conditions, and exemptions that are not relevant to these special 
conditions.
    In addition to the applicable airworthiness regulations and special 
conditions, the S-40 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 and the FAA must issue a finding of 
regulatory adequacy under Sec.  611 of Public Law 92-574, the ``Noise 
Control Act of 1972.''
    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 model S-40 because of a novel or 
unusual design feature, special conditions are prescribed under the 
provisions of Sec.  21.16.
    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.  21.17(a)(2).
    Special conditions are initially applicable to the model for which 
they are issued. Should the type certificate for that model be amended 
later to include any other model that incorporates the same or similar 
novel or unusual design feature, the special conditions would also 
apply to the other model under Sec.  21.101.

Novel or Unusual Design Features

    The Spectrum S-40 will incorporate the following novel or unusual 
design features: Spectrum proposes to utilize lithium polymer (Li-Poly) 
batteries for emergency, main, and auxiliary power unit (APU) on the 
Spectrum S-40 airplane model. This type of battery possesses certain 
failure and operational characteristics, and maintenance requirements 
that differ significantly from that of the nickel cadmium (Ni-Cd) and 
lead acid rechargeable batteries currently approved for installation in 
small airplanes. Current regulations in 14 CFR part 23 do not address 
installation of Li-Poly batteries. This special condition is being 
proposed to require that all characteristics of the Li-Poly battery and 
its installation that could affect safe operation of the Spectrum S-40 
airplane are addressed, along with establishing that appropriate 
maintenance requirements must be provided to ensure electrical power is 
available from the batteries when needed.

Discussion of Comments

    Notice of proposed special conditions No. 23-08-05-SC for the 
Spectrum Aeronautical, LLC Model 40 (S-40) airplanes was published on 
December 2, 2008 (73 FR 73195). No comments were received, and the 
special conditions are adopted as proposed except for paragraphs (8), 
(9), and (10). In paragraph (8), we added the words ``state of charge'' 
to indicate the condition of the batteries. In paragraph (9), we added 
the word ``manufacturer's'' to indicate which maintenance manual we 
were discussing. Finally, in paragraph (10), we reworded the paragraph 
to clarify the intent.
    As discussed above, these special conditions are applicable to the 
Spectrum S-40. Should Spectrum Aeronautical LLC apply at a later date 
for a change to the type certificate to include another model on the 
same type certificate incorporating 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 one model of airplane. It is not a rule of general applicability and 
it affects only the applicant who applied to the FAA for approval of 
these features on the airplane.

List of Subjects in 14 CFR Part 23

    Aircraft, Aviation safety, Signs and Symbols.

0
The authority citation for these special conditions is as follows:

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

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 Spectrum Aeronautical, LLC model S-40 
airplanes.

Spectrum Aeronautical, LLC Model 40 Lithium Polymer Battery 
Installation

    In lieu of the requirements of 14 CFR part 23, Sec.  23.1353(a) 
through (e), lithium polymer batteries and battery installations on the 
Spectrum S-40 airplane must be designed and installed as follows:
    (1) 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 Li-Poly battery installation must be designed to preclude 
explosion or fire in the event of those failures.
    (2) Li-Poly batteries must be designed to preclude the occurrence 
of self-sustaining, uncontrolled increases in temperature or pressure.
    (3) No explosive or toxic gasses emitted by any Li-Poly 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.
    (4) Li-Poly batteries that contain flammable fluids must comply 
with the flammable fluid fire protection requirements of 14 CFR part 
23, Sec.  23.863(a) through (d).
    (5) No corrosive fluids or gasses that may escape from any Li-Poly 
battery may damage surrounding airplane structure or adjacent essential 
equipment.
    (6) Each Li-Poly 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.
    (7) Li-Poly battery installations must have a system to control the 
charging

[[Page 17384]]

rate of the battery automatically, so as to prevent battery overheating 
or overcharging, and
    (i) 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,
    (ii) 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.
    (8) Any Li-Poly battery installation whose function is 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.
    (9) The Instructions for Continued Airworthiness (ICAW) must 
contain recommended manufacturer's maintenance and inspection 
requirements to ensure that batteries, including single cells, meet a 
safety function level essential to the aircraft's continued 
airworthiness.
    (i) The ICAW must contain operating instructions and equipment 
limitations in an installation maintenance manual.
    (ii) The ICAW must contain installation procedures and limitation 
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 limitation must identify any unique aspects of the 
installation.
    (iii) The ICAW must contain corrective maintenance procedures to 
functionally check battery capacity at manufacturers recommended 
inspection intervals.
    (iv) The ICAW must contain scheduled servicing information to 
replace batteries at manufacturers recommended replacement time.
    (v) The ICAW must contain maintenance inspection requirements to 
visually check for a battery and/or charger degradation.
    (10) The ICAW must contain maintenance procedures to check, at 
manufacturer's recommended inspection intervals, the function of any 
batteries in a rotating stock (spares) that experience degraded charge 
retention capability or other damage due to prolonged storage.
    (11) System Safety Assessment process should address the software 
and complex hardware levels for the sensing, monitoring and warning 
systems, if these systems contain complex devices. The functional 
hazard assessment (FHA) for the system is required based on the 
intended functions described. The criticality of the specific functions 
will be determined by the safety assessment process for compliance with 
14 CFR part 23, Sec.  23.1309, and Advisory Circular 23.1309-1C 
contains acceptable means for accomplishing this requirement. For 
determining the failure condition, the criticality of a function will 
include the mitigating factors. The failure conditions must address the 
loss of function and improper operations.
    It should be noted that these special conditions are not intended 
to replace 14 CFR part 23, Sec.  23.1353 in the certification basis of 
the Spectrum model S-40 airplanes. The special conditions apply only to 
Li-Poly batteries and battery installations. The battery requirements 
of 14 CFR part 23, Sec.  23.1353 would remain in effect for batteries 
and battery installations on the Spectrum airplane that do not utilize 
Li-Poly chemistry.

    Issued in Kansas City, Missouri on April 7, 2009.
John Colomy,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E9-8582 Filed 4-14-09; 8:45 am]
BILLING CODE 4910-13-P