Special Conditions: Cessna Aircraft Company; EFIS on the Cessna 172R and 172S; Protection of Systems for High Intensity Radiated Fields (HIRF), 11841-11844 [05-4745]
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Federal Register / Vol. 70, No. 46 / Thursday, March 10, 2005 / Rules and Regulations
to or greater than the forward static
design longitudinal load factor required
by the original certification basis of the
Applicability
airplane.
As discussed above, these special
c. The means of protection must take
conditions are applicable to the Mooney into consideration a range of stature
models M20 (K, M, R, and S) equipped
from a 5th percentile female to a 95th
with the AMSAFE, Inc., three-point
percentile male. The inflatable restraint
inflatable restraint system. Should
must provide a consistent approach to
AMSAFE, Inc., apply at a later date for
energy absorption throughout the range.
2. The inflatable restraint must
a supplemental type certificate to
provide adequate protection for each
modify any other model on the Type
occupant. In addition, unoccupied seats
Certificates identified in these special
that have an active restraint must not
conditions to incorporate the same
constitute a hazard to any occupant.
novel or unusual design feature, the
3. The design must prevent the
special conditions would also apply to
the other model under the provisions of inflatable restraint from either being
incorrectly buckled or incorrectly
§ 21.101.
installed, or both, such that the airbag
Conclusion
would not properly deploy.
This action affects only certain novel
Alternatively, it must be shown that
or unusual design features on the
such deployment is not hazardous to the
Mooney models M20 (K, M, R, and S).
occupant and will provide the required
It is not a rule of general applicability,
protection.
4. It must be shown that the inflatable
and it affects only the applicant who
applied to the FAA for approval of these restraint system is not susceptible to
inadvertent deployment as a result of
features on the airplane.
wear and tear or the inertial loads
List of Subjects in 14 CFR Part 23
resulting from in-flight or ground
Aircraft, Aviation safety, Signs and
maneuvers (including gusts and hard
symbols.
landings) that are likely to be
experienced in service.
Citation
5. It must be extremely improbable for
I The authority citation for these special
an inadvertent deployment of the
conditions is as follows:
restraint system to occur, or an
inadvertent deployment must not
Authority: 49 U.S.C. 106(g), 40113 and
44701; 14 CFR 21.16 and 21.101; and 14 CFR impede the pilot’s ability to maintain
11.38 and 11.19.
control of the airplane or cause an
unsafe condition (or hazard to the
The Special Conditions
airplane). In addition, a deployed
inflatable restraint must be at least as
I The FAA has determined that this
project will be accomplished on the basis strong as a Technical Standard Order
of not lowering the current level of safety (C114) certificated belt and shoulder
harness.
for the Mooney models M20 (K, M, R,
6. It must be shown that deployment
and S) occupant restraint system.
of the inflatable restraint system is not
Accordingly, pursuant to the authority
hazardous to the occupant and will not
delegated to me by the Administrator,
result in injuries that could impede
the following special conditions are
rapid egress. This assessment should
issued as part of the type certification
basis for the Mooney models M20 (K, M, include occupants whose restraint is
R, and S), as modified by AMSAFE, Inc. loosely fastened.
7. It must be shown that an
Inflatable Three-Point Restraint Safety
Belt with an Integrated Airbag Device on inadvertent deployment that could
cause injury to a standing or sitting
Mooney Models M20 (K, M, R, and S).
1. It must be shown that the inflatable person is improbable. In addition, the
restraint must also provide suitable
restraint will deploy and provide
visual warnings that would alert rescue
protection under crash conditions.
Compliance will be demonstrated using personnel to the presence of an
inflatable restraint system.
the dynamic test condition specified in
8. It must be shown that the inflatable
§ 23.562, which may be modified as
restraint will not impede rapid egress of
follows:
the occupants 10 seconds after its
a. The peak longitudinal deceleration
may be reduced; however, the onset rate deployment.
9. For the purposes of complying with
of the deceleration must be equal to or
greater than the crash pulse identified in HIRF and lightning requirements, the
inflatable restraint system is considered
§ 23.562.
b. The peak longitudinal deceleration a critical system since its deployment
could have a hazardous effect on the
must be above the deployment
airplane.
threshold of the crash sensor and equal
published on January 19, 2005 (70 FR
2977). No comments were received.
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10. It must be shown that the
inflatable restraints will not release
hazardous quantities of gas or
particulate matter into the cabin.
11. The inflatable restraint system
installation must be protected from the
effects of fire such that no hazard to
occupants will result.
12. There must be a means to verify
the integrity of the inflatable restraint
activation system before each flight or it
must be demonstrated to reliably
operate between inspection intervals.
13. A life limit must be established for
appropriate system components.
14. Qualification testing of the
internal firing mechanism must be
performed at vibration levels
appropriate for a general aviation
airplane.
Issued in Kansas City, Missouri on
February 25, 2005.
David R. Showers,
Acting Manager, Small Airplane Directorate,
Aircraft Certification Service.
[FR Doc. 05–4649 Filed 3–9–05; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 23
[Docket No. CE219, Special Condition No.
23–159–SC]
Special Conditions: Cessna Aircraft
Company; EFIS on the Cessna 172R
and 172S; Protection of Systems for
High Intensity Radiated Fields (HIRF)
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions; request
for comments.
AGENCY:
SUMMARY: These special conditions are
issued for the Cessna Aircraft Company,
Model 172R and 172S airplanes. These
airplanes, as modified by Cessna
Aircraft Company, will have a novel or
unusual design feature(s) associated
with the installation of a Garmin G1000
electronic flight instrument system
(EFIS) and the protection of this system
from the effects of high intensity
radiated field (HIRF) environments. 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 March 2, 2005.
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Federal Register / Vol. 70, No. 46 / Thursday, March 10, 2005 / Rules and Regulations
Comments must be received on or
before April 11, 2005.
ADDRESSES: Comments may be mailed
in duplicate to: Federal Aviation
Administration, Regional Counsel,
ACE–7, Attention: Rules Docket Clerk,
Docket No. marked: Docket No. CE219.
Comments may be inspected in the
Rules Docket weekdays, except Federal
holidays, between 7:30 a.m. and 4 p.m.
FOR FURTHER INFORMATION CONTACT: Wes
Ryan, Aerospace Engineer, Standards
Office (ACE–110), Small Airplane
Directorate, Aircraft Certification
Service, Federal Aviation
Administration, 901 Locust, Room 301,
Kansas City, Missouri 64106; telephone
(816) 329–4127.
SUPPLEMENTARY INFORMATION: The FAA
has determined that notice and
opportunity for prior public comment
hereon are impracticable because these
procedures would significantly delay
issuance of the design approval and
thus delivery of the affected aircraft. In
addition, the substance of these special
conditions 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.
Comments Invited
Interested persons are invited to
submit such written data, views, or
arguments, as they may desire.
Communications should identify the
regulatory docket or notice number and
be submitted in duplicate to the address
specified above. All communications
received on or before the closing date
for comments will be considered by the
Administrator. The special conditions
may be changed in light of the
comments received. All comments
received will be available in the Rules
Docket for examination by interested
persons, both before and after the
closing date for comments. A report
summarizing each substantive public
contact with FAA personnel concerning
this rulemaking will be filed in the
docket. Commenters wishing the FAA to
acknowledge receipt of their comments
submitted in response to this notice
must include a self-addressed, stamped
postcard on which the following
statement is made: ‘‘Comments to
Docket No. CE219.’’ The postcard will
be date stamped and returned to the
commenter.
Background
On January 28, 2004, Cessna Aircraft
Company; One Cessna Boulevard; Post
Office Box 7704; Wichita, KS 67277,
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made an application to the FAA for an
amended type certificate for the Cessna
172R and 172S. The 172R and 172S are
currently approved under TC No. 3A12.
The proposed modification incorporates
a novel or unusual design feature, such
as digital avionics consisting of an EFIS
that may be vulnerable to HIRF external
to the airplane.
Type Certification Basis
Under the provisions of 14 CFR part
21, § 21.101, Cessna Aircraft Company
must show that the Cessna Model 172R
and 172S meet the following provisions
or the applicable provisions in effect on
the date of application for type
certification of the Cessna 172R and
172S.
For the 172R Series:
14 CFR part 23 of the Federal
Aviation Regulations effective February
1, 1965, as amended by 23–1 through
23–6, except as follows: Sec. 23.423;
23.611; 23.619; 23.623; 23.689; 23.775;
23.871; 23.1323; and 23.1563 as
amended by Amendment 23–7. Sections
23.807 and 23.1524 as amended by
Amendment 23–10. Sections 23.507;
23.771; 23.853(a), (b) and (c); and
23.1365 as amended by Amendment 23–
14. Section 23.951 as amended by
Amendment 23–15. Sections 23.607;
23.675; 23.685; 23.733; 23.787; 23.1309
and 23.1322 as amended by
Amendment 23–17. Section 23.1301 as
amended by Amendment 23–20. Section
23.1353; and 23.1559 as amended by
Amendment 23–21. Sections 23.603;
23.605; 23.613; 23.1329 and 23.1545 as
amended by Amendment 23–23.
Sections 23.441 and 23.1549 as
amended by Amendment 23–28.
Sections 23.779 and 23.781 as amended
by Amendment 23–33. Sections 23.1;
23.51 and 23.561 as amended by
Amendment 23–34. Sections 23.301;
23.331; 23.351; 23.427; 23.677; 23.701;
23.735; and 23.831 as amended by
Amendment 23–42. Sections 23.961;
23.1093; 23.1143(g); 23.1147(b);
23.1303; 23.1357; 23.1361 and 23.1385
as amended by Amendment 23–43.
Sections 23.562(a), 23.562(b)2,
23.562(c)1, 23.562(c)2, 23.562(c)3, and
23.562(c)4 as amended by Amendment
23–44. Sections 23.33; 23.53; 23.305;
23.321; 23.485; 23.621; 23.655 and
23.731 as amended by Amendment 23–
45. 14 CFR part 36 dated December 1,
1969, as amended by Amendments 36–
1 through 36–21, additional certification
requirements applied to the G1000
system itself, such as 23.1309 and
23.1311 as amended by Amendment 23–
49, 23.1321 as amended by Amendment
23–41, and 23.1322 as amended by
Amendment 23–43, exemptions, if any;
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and the special conditions adopted by
this rulemaking action.
For the 172S series:
14 CFR part 23 effective February 1,
1965, as amended by 23–1 through 23–
6, except as follows: Sections 23.423;
23.611; 23.619; 23.623; 23.689; 23.775;
23.871; 23.1323; and 23.1563 as
amended by Amendment 23–7. Sections
23.807 and 23.1524 as amended by
Amendment 23–10. Sections 23.507;
23.771; 23.853(a), (b) and (c); and
23.1365 as amended by Amendment 23–
14. Section 23.951 as amended by
Amendment 23–15. Sections 23.607;
23.675; 23.685; 23.733; 23.787; 23.1309
and 23.1322 as amended by
Amendment 23–17. Section 23.1301 as
amended by Amendment 23–20.
Sections 23.1353; and 23.1559 as
amended by Amendment 23–21.
Sections 23.603; 23.605; 23.613; 23.1329
and 23.1545 as amended by
Amendment 23–23. Sections 23.441 and
23.1549 as amended by Amendment 23–
28. Sections 23.779 and 23.781 as
amended by Amendment 23–33.
Sections 23.1; 23.51 and 23.561 as
amended by Amendment 23–34.
Sections 23.301; 23.331; 23.351; 23.427;
23.677; 23.701; 23.735; and 23.831 as
amended by Amendment 23–42.
Sections 23.961; 23.1093; 23.1143(g);
23.1147(b); 23.1303; 23.1357; 23.1361
and 23.1385 as amended by
Amendment 23–43. Sections 23.562(a),
23.562(b)2, 23.562(c)1, 23.562(c)2,
23.562(c)3, and 23.562(c)4 as amended
by Amendment 23–44. Sections 23.33;
23.53; 23.305; 23.321; 23.485; 23.621;
23.655 and 23.731 as amended by
Amendment 23–45. 14 CFR part 36
dated December 1, 1969, as amended by
Amendments 36–1 through 36–21,
additional certification requirements
applied to the G1000 system itself, such
as 23.1309 and 23.1311 as amended by
Amendment 23–49, 23.1321 as amended
by Amendment 23–41, and 23.1322 as
amended by Amendment 23–43,
exemptions, if any; and the special
conditions adopted by this rulemaking
action.
Discussion
If the Administrator finds that the
applicable airworthiness standards do
not contain adequate or appropriate
safety standards because of novel or
unusual design features of an airplane,
special conditions are prescribed under
the provisions of § 21.16.
Special conditions, as appropriate, as
defined in § 11.19, are issued in
accordance with § 11.38 after public
notice and become part of the type
certification basis in accordance with
§ 21.101.
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Federal Register / Vol. 70, No. 46 / Thursday, March 10, 2005 / Rules and Regulations
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 novel or unusual
design feature, the special conditions
would also apply to the other model
under the provisions of § 21.101.
Novel or Unusual Design Features
The Cessna Model 172R and Model
172S will incorporate the following
novel or unusual design features: A
Garmin G1000 electronic flight
instrument system (EFIS) including a
primary flight display on the pilot side
as well as a multifunction display in the
center of the instrument panel.
Protection of Systems From High
Intensity Radiated Fields (HIRF): Recent
advances in technology have given rise
to the application in aircraft designs of
advanced electrical and electronic
systems that perform functions required
for continued safe flight and landing.
Due to the use of sensitive solid-state
advanced components in analog and
digital electronics circuits, these
advanced systems are readily responsive
to the transient effects of induced
electrical current and voltage caused by
the HIRF. The HIRF can degrade
electronic systems performance by
damaging components or upsetting
system functions.
Furthermore, the HIRF environment
has undergone a transformation that was
not foreseen when the current
requirements were developed. Higher
energy levels are radiated from
transmitters that are used for radar,
radio, and television. Also, the number
of transmitters has increased
significantly. There is also uncertainty
concerning the effectiveness of airframe
shielding for HIRF. Furthermore,
coupling to cockpit-installed equipment
through the cockpit window apertures is
undefined.
The combined effect of the
technological advances in airplane
design and the changing environment
has resulted in an increased level of
vulnerability of electrical and electronic
systems required for the continued safe
flight and landing of the airplane.
Effective measures against the effects of
exposure to HIRF must be provided by
the design and installation of these
systems. The accepted maximum energy
levels in which civilian airplane system
installations must be capable of
operating safely are based on surveys
and analysis of existing radio frequency
emitters. These special conditions
require that the airplane be evaluated
under these energy levels for the
protection of the electronic system and
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its associated wiring harness. These
external threat levels, which are lower
than previous required values, are
believed to represent the worst case to
which an airplane would be exposed in
the operating environment.
These special conditions require
qualification of systems that perform
critical functions, as installed in aircraft,
to the defined HIRF environment in
paragraph 1 or, as an option to a fixed
value using laboratory tests, in
paragraph 2, as follows:
(1) The applicant may demonstrate
that the operation and operational
capability of the installed electrical and
electronic systems that perform critical
functions are not adversely affected
when the aircraft is exposed to the HIRF
environment defined below:
Field strength
(volts per meter)
Frequency
Peak
10 kHz–100kHz ............
100 kHz–500 kHz .........
500 kHz–2 MHz ............
2 MHz–30 MHz .............
30 MHz–70 MHz ...........
70 MHz–100 MHz .........
100 MHz–200 MHz .......
200 MHz–400 MHz .......
400 MHz–700 MHz .......
700 MHz–1 GHz ...........
1 GHz–2 GHz ...............
2 GHz–4 GHz ...............
4 GHz–6 GHz ...............
6 GHz–8 GHz ...............
8 GHz–12 GHz .............
12 GHz–18 GHz ...........
18 GHz–40 GHz ...........
50
50
50
100
50
50
100
100
700
700
2000
3000
3000
1000
3000
2000
600
Average
50
50
50
100
50
50
100
100
50
100
200
200
200
200
300
200
200
The field strengths are expressed in
terms of peak root-mean-square (rms)
values.
or,
(2) The applicant may demonstrate by
a system test and analysis that the
electrical and electronic systems that
perform critical functions can withstand
a minimum threat of 100 volts per
meter, electrical field strength, from 10
kHz to 18 GHz. When using this test to
show compliance with the HIRF
requirements, no credit is given for
signal attenuation due to installation.
A preliminary hazard analysis must
be performed by the applicant for
approval by the FAA to identify either
electrical or electronic systems that
perform critical functions. The term
‘‘critical’’ means those functions, whose
failure would contribute to, or cause, a
failure condition that would prevent the
continued safe flight and landing of the
airplane. The systems identified by the
hazard analysis that perform critical
functions are candidates for the
application of HIRF requirements. A
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11843
system may perform both critical and
non-critical functions. Primary
electronic flight display systems, and
their associated components, perform
critical functions such as attitude,
altitude, and airspeed indication. The
HIRF requirements apply only to critical
functions.
Compliance with HIRF requirements
may be demonstrated by tests, analysis,
models, similarity with existing
systems, or any combination of these.
Service experience alone is not
acceptable since normal flight
operations may not include an exposure
to the HIRF environment. Reliance on a
system with similar design features for
redundancy as a means of protection
against the effects of external HIRF is
generally insufficient since all elements
of a redundant system are likely to be
exposed to the fields concurrently.
Applicability
As discussed above, these special
conditions are applicable to the Cessna
172R and 172S airplanes. Should the
Cessna Aircraft Company apply at a
later date to modify any other model on
the same type certificate to incorporate
the same novel or unusual design
feature, the special conditions would
apply to that model as well under the
provisions of § 21.101.
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 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 substance
contained herein. For this reason, and
because a delay would significantly
affect the certification of the airplane,
which is imminent, the FAA has
determined that prior public notice and
comment are unnecessary and
impracticable, and good cause exists for
adopting these special conditions 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.
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Federal Register / Vol. 70, No. 46 / Thursday, March 10, 2005 / Rules and Regulations
01, 788945, 753187, and 807410, knifeedges for cracks, each time the engine’s
I The authority citation for these special
HPT second stage airseal is accessible.
conditions is as follows:
This AD requires replacing each existing
Authority: 49 U.S.C. 106(g), 40113 and
HPT second stage airseal with an
44701; 14 CFR 21.16 and 21.17; and 14 CFR
improved design HPT second stage
11.38 and 11.19.
airseal and modifying the 2nd stage HPT
vane cluster assembly and 1st stage
The Special Conditions
retaining blade HPT plate assembly at
I Accordingly, pursuant to the authority
next piece-part exposure, but no later
delegated to me by the Administrator,
than five years after the effective date of
the following special conditions are
this AD. These actions are considered
issued as part of the type certification
basis for Cessna 172R and 172S airplanes terminating action to the repetitive
inspections required by AD 2002–10–
modified by the Cessna Aircraft
Company to add the Garmin G1000 EFIS 07. This AD results from the
manufacturer introducing an improved
system.
design HPT second stage airseal and
1. Protection of Electrical and
modifications to increase cooling. We
Electronic Systems from High Intensity
are issuing this AD to prevent failure of
Radiated Fields (HIRF). Each system
the HPT second stage airseal due to
that performs critical functions must be
designed and installed to ensure that the cracks in the knife-edges, which if not
detected, could result in uncontained
operations, and operational capabilities
engine failure and damage to the
of these systems to perform critical
airplane.
functions, are not adversely affected
when the airplane is exposed to high
DATES: This AD becomes effective April
intensity radiated electromagnetic fields 14, 2005. The Director of the Federal
external to the airplane.
Register approved the incorporation by
2. For the purpose of these special
reference of certain publications listed
conditions, the following definition
in the regulations as of April 14, 2005.
applies: Critical Functions: Functions
ADDRESSES: You can get the service
whose failure would contribute to, or
information identified in this AD from
cause, a failure condition that would
Pratt & Whitney, 400 Main St., East
prevent the continued safe flight and
Hartford, CT 06108; telephone (860)
landing of the airplane.
565–8770; fax (860) 565–4503.
Issued in Kansas City, Missouri on March
You may examine the AD docket and
2, 2005.
the service information at the FAA, New
Nancy C. Lane,
England Region, Office of the Regional
Acting Manager, Small Airplane Directorate,
Counsel, 12 New England Executive
Aircraft Certification Service.
Park, Burlington, MA.
[FR Doc. 05–4745 Filed 3–9–05; 8:45 am]
Citation
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2001–NE–27–AD; Amendment
39–14002; AD 2005–05–13]
RIN 2120–AA64
Airworthiness Directives; Pratt &
Whitney JT9D–59A, –70A, –7Q, and
–7Q3 Turbofan Engines
Federal Aviation
Administration (FAA), DOT.
ACTION: Final rule.
AGENCY:
SUMMARY: The FAA is superseding an
existing airworthiness directive (AD) for
Pratt & Whitney (PW) JT9D–59A, –70A,
–7Q, and –7Q3 turbofan engines. That
AD currently requires fluorescent
penetrant inspection (FPI) of high
pressure turbine (HPT) second stage
airseals, part numbers (P/Ns) 5002537–
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FOR FURTHER INFORMATION CONTACT:
Kevin Donovan, Aerospace Engineer,
Engine Certification Office, FAA, Engine
& Propeller Directorate, 12 New England
Executive Park, Burlington, MA 01887–
5299; telephone (781) 238–7743; fax
(781) 238–7199.
The FAA
proposed to amend 14 CFR Part 39 with
a proposed AD. The proposed AD
applies to PW JT9D–59A, –70A, –7Q,
and –7Q3 turbofan engines. We
published the proposed AD in the
Federal Register on July 7, 2004 (69 FR
40819). That action proposed to require
replacing each existing HPT second
stage airseal with an improved design
HPT second stage airseal and modifying
the 2nd stage HPT vane cluster
assembly and 1st stage retaining blade
HPT plate assembly at next piece-part
exposure, but no later than five years
after the effective date of the proposed
AD. These actions would be considered
terminating action to the repetitive
inspections required by AD 2002–10–
07.
SUPPLEMENTARY INFORMATION:
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Examining the AD Docket
You may examine the AD Docket
(including any comments and service
information), by appointment, between
8 a.m. and 4:30 p.m., Monday through
Friday, except Federal holidays. See
ADDRESSES for the location.
Comments
We provided the public the
opportunity to participate in the
development of this AD. We have
considered the comments received.
Request To Keep AD 2002–10–07 as an
Alternative Means of Compliance
One commenter requests that the
existing AD, which is AD 2002–10–07,
be kept as an alternative means of
compliance. The commenter states that
the compliance of the proposed AD, as
per the Accomplishment Instructions of
PW Service Bulletin (SB) No. JT9D
6454, Revision 1, not only requires
replacement of the HPT second stage
turbine airseal, but also requires
replacement and modification of many
other parts. Since all of the parts of the
HPT module are required to be exposed
to piece-parts during overhaul, and not
at any other time, the compliance
statement which states ‘‘At the next
piece-part exposure’’ should be
amended to ‘‘At the next HPT Module
overhaul’’, as also stated in SB No. JT9D
6454, Revision 1.
We do not agree. AD 2002–10–07 was
introduced solely as an interim action,
with the intent of the redesign being the
final solution. We are issuing this AD to
prevent failure of the HPT second stage
airseal due to cracks in the knife-edges,
which if not detected, could result in
uncontained engine failure and damage
to the airplane. Therefore we do not feel
that the AD 2002–10–07 interim action
provides an equivalent level of safety. In
addition, there are times such as an
unscheduled maintenance event, in
which the HPT module hardware will
be exposed. It is our intention to
incorporate this AD at the next piecepart exposure.
Proposal for an Alternative
Management Plan
One commenter proposes an
alternative management plan to the
compliance section in the proposed AD,
subject to the provisions in the
proposed AD. The commenter provided
the details of the proposed management
plan to us in a separate document. The
background to the proposed plan is as
follows:
HPT second stage airseals, P/Ns
5002537–01, 788945, 753187, and
807410, have very high scrap rates.
About 75% of airseals are scrapped after
E:\FR\FM\10MRR1.SGM
10MRR1
]]>Agencies
[Federal Register Volume 70, Number 46 (Thursday, March 10, 2005)]
[Rules and Regulations]
[Pages 11841-11844]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-4745]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 23
[Docket No. CE219, Special Condition No. 23-159-SC]
Special Conditions: Cessna Aircraft Company; EFIS on the Cessna
172R and 172S; Protection of Systems for High Intensity Radiated Fields
(HIRF)
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions; request for comments.
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SUMMARY: These special conditions are issued for the Cessna Aircraft
Company, Model 172R and 172S airplanes. These airplanes, as modified by
Cessna Aircraft Company, will have a novel or unusual design feature(s)
associated with the installation of a Garmin G1000 electronic flight
instrument system (EFIS) and the protection of this system from the
effects of high intensity radiated field (HIRF) environments. 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 March 2, 2005.
[[Page 11842]]
Comments must be received on or before April 11, 2005.
ADDRESSES: Comments may be mailed in duplicate to: Federal Aviation
Administration, Regional Counsel, ACE-7, Attention: Rules Docket Clerk,
Docket No. marked: Docket No. CE219. Comments may be inspected in the
Rules Docket weekdays, except Federal holidays, between 7:30 a.m. and 4
p.m.
FOR FURTHER INFORMATION CONTACT: Wes Ryan, Aerospace Engineer,
Standards Office (ACE-110), Small Airplane Directorate, Aircraft
Certification Service, Federal Aviation Administration, 901 Locust,
Room 301, Kansas City, Missouri 64106; telephone (816) 329-4127.
SUPPLEMENTARY INFORMATION: The FAA has determined that notice and
opportunity for prior public comment hereon are impracticable because
these procedures would significantly delay issuance of the design
approval and thus delivery of the affected aircraft. In addition, the
substance of these special conditions 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.
Comments Invited
Interested persons are invited to submit such written data, views,
or arguments, as they may desire. Communications should identify the
regulatory docket or notice number and be submitted in duplicate to the
address specified above. All communications received on or before the
closing date for comments will be considered by the Administrator. The
special conditions may be changed in light of the comments received.
All comments received will be available in the Rules Docket for
examination by interested persons, both before and after the closing
date for comments. A report summarizing each substantive public contact
with FAA personnel concerning this rulemaking will be filed in the
docket. Commenters wishing the FAA to acknowledge receipt of their
comments submitted in response to this notice must include a self-
addressed, stamped postcard on which the following statement is made:
``Comments to Docket No. CE219.'' The postcard will be date stamped and
returned to the commenter.
Background
On January 28, 2004, Cessna Aircraft Company; One Cessna Boulevard;
Post Office Box 7704; Wichita, KS 67277, made an application to the FAA
for an amended type certificate for the Cessna 172R and 172S. The 172R
and 172S are currently approved under TC No. 3A12. The proposed
modification incorporates a novel or unusual design feature, such as
digital avionics consisting of an EFIS that may be vulnerable to HIRF
external to the airplane.
Type Certification Basis
Under the provisions of 14 CFR part 21, Sec. 21.101, Cessna
Aircraft Company must show that the Cessna Model 172R and 172S meet the
following provisions or the applicable provisions in effect on the date
of application for type certification of the Cessna 172R and 172S.
For the 172R Series:
14 CFR part 23 of the Federal Aviation Regulations effective
February 1, 1965, as amended by 23-1 through 23-6, except as follows:
Sec. 23.423; 23.611; 23.619; 23.623; 23.689; 23.775; 23.871; 23.1323;
and 23.1563 as amended by Amendment 23-7. Sections 23.807 and 23.1524
as amended by Amendment 23-10. Sections 23.507; 23.771; 23.853(a), (b)
and (c); and 23.1365 as amended by Amendment 23-14. Section 23.951 as
amended by Amendment 23-15. Sections 23.607; 23.675; 23.685; 23.733;
23.787; 23.1309 and 23.1322 as amended by Amendment 23-17. Section
23.1301 as amended by Amendment 23-20. Section 23.1353; and 23.1559 as
amended by Amendment 23-21. Sections 23.603; 23.605; 23.613; 23.1329
and 23.1545 as amended by Amendment 23-23. Sections 23.441 and 23.1549
as amended by Amendment 23-28. Sections 23.779 and 23.781 as amended by
Amendment 23-33. Sections 23.1; 23.51 and 23.561 as amended by
Amendment 23-34. Sections 23.301; 23.331; 23.351; 23.427; 23.677;
23.701; 23.735; and 23.831 as amended by Amendment 23-42. Sections
23.961; 23.1093; 23.1143(g); 23.1147(b); 23.1303; 23.1357; 23.1361 and
23.1385 as amended by Amendment 23-43. Sections 23.562(a), 23.562(b)2,
23.562(c)1, 23.562(c)2, 23.562(c)3, and 23.562(c)4 as amended by
Amendment 23-44. Sections 23.33; 23.53; 23.305; 23.321; 23.485; 23.621;
23.655 and 23.731 as amended by Amendment 23-45. 14 CFR part 36 dated
December 1, 1969, as amended by Amendments 36-1 through 36-21,
additional certification requirements applied to the G1000 system
itself, such as 23.1309 and 23.1311 as amended by Amendment 23-49,
23.1321 as amended by Amendment 23-41, and 23.1322 as amended by
Amendment 23-43, exemptions, if any; and the special conditions adopted
by this rulemaking action.
For the 172S series:
14 CFR part 23 effective February 1, 1965, as amended by 23-1
through 23-6, except as follows: Sections 23.423; 23.611; 23.619;
23.623; 23.689; 23.775; 23.871; 23.1323; and 23.1563 as amended by
Amendment 23-7. Sections 23.807 and 23.1524 as amended by Amendment 23-
10. Sections 23.507; 23.771; 23.853(a), (b) and (c); and 23.1365 as
amended by Amendment 23-14. Section 23.951 as amended by Amendment 23-
15. Sections 23.607; 23.675; 23.685; 23.733; 23.787; 23.1309 and
23.1322 as amended by Amendment 23-17. Section 23.1301 as amended by
Amendment 23-20. Sections 23.1353; and 23.1559 as amended by Amendment
23-21. Sections 23.603; 23.605; 23.613; 23.1329 and 23.1545 as amended
by Amendment 23-23. Sections 23.441 and 23.1549 as amended by Amendment
23-28. Sections 23.779 and 23.781 as amended by Amendment 23-33.
Sections 23.1; 23.51 and 23.561 as amended by Amendment 23-34. Sections
23.301; 23.331; 23.351; 23.427; 23.677; 23.701; 23.735; and 23.831 as
amended by Amendment 23-42. Sections 23.961; 23.1093; 23.1143(g);
23.1147(b); 23.1303; 23.1357; 23.1361 and 23.1385 as amended by
Amendment 23-43. Sections 23.562(a), 23.562(b)2, 23.562(c)1,
23.562(c)2, 23.562(c)3, and 23.562(c)4 as amended by Amendment 23-44.
Sections 23.33; 23.53; 23.305; 23.321; 23.485; 23.621; 23.655 and
23.731 as amended by Amendment 23-45. 14 CFR part 36 dated December 1,
1969, as amended by Amendments 36-1 through 36-21, additional
certification requirements applied to the G1000 system itself, such as
23.1309 and 23.1311 as amended by Amendment 23-49, 23.1321 as amended
by Amendment 23-41, and 23.1322 as amended by Amendment 23-43,
exemptions, if any; and the special conditions adopted by this
rulemaking action.
Discussion
If the Administrator finds that the applicable airworthiness
standards do not contain adequate or appropriate safety standards
because of novel or unusual design features of an airplane, special
conditions are prescribed under the provisions of Sec. 21.16.
Special conditions, as appropriate, as defined in Sec. 11.19, are
issued in accordance with Sec. 11.38 after public notice and become
part of the type certification basis in accordance with Sec. 21.101.
[[Page 11843]]
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 novel or
unusual design feature, the special conditions would also apply to the
other model under the provisions of Sec. 21.101.
Novel or Unusual Design Features
The Cessna Model 172R and Model 172S will incorporate the following
novel or unusual design features: A Garmin G1000 electronic flight
instrument system (EFIS) including a primary flight display on the
pilot side as well as a multifunction display in the center of the
instrument panel.
Protection of Systems From High Intensity Radiated Fields (HIRF):
Recent advances in technology have given rise to the application in
aircraft designs of advanced electrical and electronic systems that
perform functions required for continued safe flight and landing. Due
to the use of sensitive solid-state advanced components in analog and
digital electronics circuits, these advanced systems are readily
responsive to the transient effects of induced electrical current and
voltage caused by the HIRF. The HIRF can degrade electronic systems
performance by damaging components or upsetting system functions.
Furthermore, the HIRF environment has undergone a transformation
that was not foreseen when the current requirements were developed.
Higher energy levels are radiated from transmitters that are used for
radar, radio, and television. Also, the number of transmitters has
increased significantly. There is also uncertainty concerning the
effectiveness of airframe shielding for HIRF. Furthermore, coupling to
cockpit-installed equipment through the cockpit window apertures is
undefined.
The combined effect of the technological advances in airplane
design and the changing environment has resulted in an increased level
of vulnerability of electrical and electronic systems required for the
continued safe flight and landing of the airplane. Effective measures
against the effects of exposure to HIRF must be provided by the design
and installation of these systems. The accepted maximum energy levels
in which civilian airplane system installations must be capable of
operating safely are based on surveys and analysis of existing radio
frequency emitters. These special conditions require that the airplane
be evaluated under these energy levels for the protection of the
electronic system and its associated wiring harness. These external
threat levels, which are lower than previous required values, are
believed to represent the worst case to which an airplane would be
exposed in the operating environment.
These special conditions require qualification of systems that
perform critical functions, as installed in aircraft, to the defined
HIRF environment in paragraph 1 or, as an option to a fixed value using
laboratory tests, in paragraph 2, as follows:
(1) The applicant may demonstrate that the operation and
operational capability of the installed electrical and electronic
systems that perform critical functions are not adversely affected when
the aircraft is exposed to the HIRF environment defined below:
------------------------------------------------------------------------
Field strength
(volts per meter)
Frequency -------------------
Peak Average
------------------------------------------------------------------------
10 kHz-100kHz....................................... 50 50
100 kHz-500 kHz..................................... 50 50
500 kHz-2 MHz....................................... 50 50
2 MHz-30 MHz........................................ 100 100
30 MHz-70 MHz....................................... 50 50
70 MHz-100 MHz...................................... 50 50
100 MHz-200 MHz..................................... 100 100
200 MHz-400 MHz..................................... 100 100
400 MHz-700 MHz..................................... 700 50
700 MHz-1 GHz....................................... 700 100
1 GHz-2 GHz......................................... 2000 200
2 GHz-4 GHz......................................... 3000 200
4 GHz-6 GHz......................................... 3000 200
6 GHz-8 GHz......................................... 1000 200
8 GHz-12 GHz........................................ 3000 300
12 GHz-18 GHz....................................... 2000 200
18 GHz-40 GHz....................................... 600 200
------------------------------------------------------------------------
The field strengths are expressed in terms of peak root-mean-square
(rms) values.
or,
(2) The applicant may demonstrate by a system test and analysis
that the electrical and electronic systems that perform critical
functions can withstand a minimum threat of 100 volts per meter,
electrical field strength, from 10 kHz to 18 GHz. When using this test
to show compliance with the HIRF requirements, no credit is given for
signal attenuation due to installation.
A preliminary hazard analysis must be performed by the applicant
for approval by the FAA to identify either electrical or electronic
systems that perform critical functions. The term ``critical'' means
those functions, whose failure would contribute to, or cause, a failure
condition that would prevent the continued safe flight and landing of
the airplane. The systems identified by the hazard analysis that
perform critical functions are candidates for the application of HIRF
requirements. A system may perform both critical and non-critical
functions. Primary electronic flight display systems, and their
associated components, perform critical functions such as attitude,
altitude, and airspeed indication. The HIRF requirements apply only to
critical functions.
Compliance with HIRF requirements may be demonstrated by tests,
analysis, models, similarity with existing systems, or any combination
of these. Service experience alone is not acceptable since normal
flight operations may not include an exposure to the HIRF environment.
Reliance on a system with similar design features for redundancy as a
means of protection against the effects of external HIRF is generally
insufficient since all elements of a redundant system are likely to be
exposed to the fields concurrently.
Applicability
As discussed above, these special conditions are applicable to the
Cessna 172R and 172S airplanes. Should the Cessna Aircraft Company
apply at a later date to modify any other model on the same type
certificate to incorporate the same novel or unusual design feature,
the special conditions would apply to that model as well under the
provisions of Sec. 21.101.
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
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 substance contained herein. For this reason, and because a
delay would significantly affect the certification of the airplane,
which is imminent, the FAA has determined that prior public notice and
comment are unnecessary and impracticable, and good cause exists for
adopting these special conditions 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.
[[Page 11844]]
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
21.17; and 14 CFR 11.38 and 11.19.
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 172R and 172S airplanes
modified by the Cessna Aircraft Company to add the Garmin G1000 EFIS
system.
1. Protection of Electrical and Electronic Systems from High
Intensity Radiated Fields (HIRF). Each system that performs critical
functions must be designed and installed to ensure that the operations,
and operational capabilities of these systems to perform critical
functions, are not adversely affected when the airplane is exposed to
high intensity radiated electromagnetic fields external to the
airplane.
2. For the purpose of these special conditions, the following
definition applies: Critical Functions: Functions whose failure would
contribute to, or cause, a failure condition that would prevent the
continued safe flight and landing of the airplane.
Issued in Kansas City, Missouri on March 2, 2005.
Nancy C. Lane,
Acting Manager, Small Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 05-4745 Filed 3-9-05; 8:45 am]
BILLING CODE 4910-13-P
