Special Conditions: Gulfstream Model GVI Airplane; Limit Engine Torque Loads for Sudden Engine Stoppage, 25648-25650 [2011-10922]
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Federal Register / Vol. 76, No. 87 / Thursday, May 5, 2011 / Proposed Rules
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VerDate Mar<15>2010
19:33 May 04, 2011
Jkt 223001
explanation of the competitive injury to
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It is DOE’s policy that all comments
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without change and as received,
including any personal information
provided in the comments (except
information deemed to be exempt from
public disclosure).
B. Issues on Which DOE Seeks Comment
Although DOE welcomes comments
on any aspect of this notice, DOE is
particularly interested in receiving
comments and views of interested
parties concerning the following issues:
(1) The impact of proposed addenda
h, i, and j to ASHRAE Standard 90.1–
2010 on the energy savings presented in
today’s NODA;
(2) The energy savings potential of
small and large evaporatively-cooled
commercial package air conditioners;
(3) The market for VRF water-source
heat pumps with cooling capacities
below 17,000 Btu/h and above 135,000
Btu/h. DOE is seeking data and
information that would allow it to
accurately characterize the energy
savings from amended energy
conservation standards for these
products;
(4) The market for large and very large
SPVACs and SPVHPs;
(5) Approaches for establishing energy
conservation standards for covering air
conditioners and condensing units
serving computer rooms;
(6) Data and information for air
conditioners and condensing units
serving computer rooms that could be
used in performing an energy savings
analysis at a future stage of this
rulemaking;
(7) Approaches for developing
appropriate definitions for ‘‘air
conditioners and condensing units
serving computer rooms’’ that would not
result in overlap between this
equipment and the other types of
commercial packaged air conditioning
and heating equipment covered by
EPCA;
(8) The use of AHRI 1230, ASHRAE
127, and AHRI 390 as the test method
for VRF equipment, air conditioners and
condensing units serving computer
rooms, and SPVACs and SPVHPs,
respectively; and
(9) DOE’s preliminary conclusion that
the updates to the most recent versions
of AHRI 210/240, AHRI 340/360, UL
727, ANSI Z21.47, and ANSI Z21.10.3
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Fmt 4702
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do not have a substantive impact on the
measurement of energy efficiency for
the associated equipment types for each
test procedure;
(10) DOE’s analysis of UEC for the
water-cooled, evaporatively-cooled,
SVPU equipment classes and its use in
establishing the energy savings potential
for higher standards. Of particular
interest are other building applications
for SPVU equipment and the value of
incorporating these into the analysis of
UEC.
(11) DOE’s allocation of shipments to
the eight classes of water-cooled and
evaporatively-cooled equipment for
which analysis was performed, as well
as the future market and shipment
scenarios for these products; and
(12) DOE’s determination of the basecase distribution efficiencies and its
prediction on how amended energy
conservation standards affect the
distribution of efficiencies in the
standards case for the twelve classes of
equipment for which analysis was
performed.
V. Approval of the Office of the
Secretary
The Secretary of Energy has approved
publication of this notice of data
availability.
Issued in Washington, DC, on April 27,
2011.
Kathleen Hogan,
Deputy Assistant Secretary for Energy
Efficiency, Office of Technology
Development, Energy Efficiency and
Renewable Energy.
[FR Doc. 2011–10877 Filed 5–4–11; 8:45 am]
BILLING CODE 6450–01–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. NM454 Special Conditions No.
25–11–11–SC]
Special Conditions: Gulfstream Model
GVI Airplane; Limit Engine Torque
Loads for Sudden Engine Stoppage
Federal Aviation
Administration (FAA), DOT.
ACTION: Notice of proposed special
conditions.
AGENCY:
This action proposes special
conditions for the Gulfstream GVI
airplane. This airplane will have novel
or unusual design features when
compared to the state of technology
envisioned in the airworthiness
standards for transport category
airplanes. These design features include
SUMMARY:
E:\FR\FM\05MYP1.SGM
05MYP1
Federal Register / Vol. 76, No. 87 / Thursday, May 5, 2011 / Proposed Rules
emcdonald on DSK2BSOYB1PROD with PROPOSALS
engine size and the potential torque
load imposed by sudden engine
stoppage. These proposed special
conditions pertain to their effects on the
structural performance of the airplane.
The applicable airworthiness
regulations do not contain adequate or
appropriate safety standards for these
design features. These proposed special
conditions contain the additional safety
standards that the Administrator
considers necessary to establish a level
of safety equivalent to that established
by the existing airworthiness standards.
DATES: We must receive your comments
by June 20, 2011.
ADDRESSES: You must mail two copies
of your comments to: Federal Aviation
Administration, Transport Airplane
Directorate, Attn: Rules Docket (ANM–
113), Docket No. NM454, 1601 Lind
Avenue SW., Renton, Washington
98057–3356. You may deliver two
copies to the Transport Airplane
Directorate at the above address. You
must mark your comments: Docket No.
NM454. You can inspect comments in
the Rules Docket weekdays, except
Federal holidays, between 7:30 a.m. and
4 p.m.
FOR FURTHER INFORMATION CONTACT: Carl
Niedermeyer, FAA, Airframe/Cabin
Safety Branch, ANM–115, Transport
Standards Staff, Transport Airplane
Directorate, Aircraft Certification
Service, 1601 Lind Avenue SW.,
Renton, Washington 98057–3356;
telephone (425) 227–2279; electronic
mail Carl.Neidermeyer@faa.gov.
SUPPLEMENTARY INFORMATION:
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 file in the docket all
comments we receive, as well as a
report summarizing each substantive
public contact with FAA personnel
concerning these special conditions.
You can inspect the docket before and
after the comment closing date. If you
wish to review the docket in person, go
to the address in the ADDRESSES section
of this preamble between 7:30 a.m. and
4 p.m., Monday through Friday, except
Federal holidays.
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
VerDate Mar<15>2010
19:33 May 04, 2011
Jkt 223001
may change these special conditions
based on the comments we receive.
If you want us to acknowledge receipt
of your comments on this proposal,
include with your comments a selfaddressed, stamped postcard on which
you have written the docket number.
We will stamp the date on the postcard
and mail it back to you.
Background
On March 29, 2005, Gulfstream
Aerospace Corporation (hereafter
referred to as ‘‘Gulfstream’’) applied for
an FAA type certificate for its new
Gulfstream Model GVI passenger
airplane. Gulfstream later applied for,
and was granted, an extension of time
for the type certificate, which changed
the effective application date to
September 28, 2006. The Gulfstream
Model GVI airplane will be an all-new,
two-engine jet transport airplane with
an executive cabin interior. The
maximum takeoff weight will be 99,600
pounds, with a maximum passenger
count of 19 passengers.
Type Certification Basis
Under provisions of Title 14, Code of
Federal Regulations (14 CFR) 21.17,
Gulfstream must show that the
Gulfstream Model GVI airplane
(hereafter referred to as ‘‘the GVI’’) meets
the applicable provisions of 14 CFR part
25, as amended by Amendments 25–1
through 25–119, 25–122, and 25.124. If
the Administrator finds that the
applicable airworthiness regulations
(i.e., 14 CFR part 25) do not contain
adequate or appropriate safety standards
for the GVI because of a novel or
unusual design feature, special
conditions are prescribed under the
provisions of § 21.16.
Special conditions are initially
applicable to the 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 features, the special conditions
would also apply to the other model
under provisions of § 21.101.
In addition to complying with the
applicable airworthiness regulations
and special conditions, the GVI 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 must also issue a finding of
regulatory adequacy pursuant to section
611 of Public Law 92–574, the ‘‘Noise
Control Act of 1972.’’
The FAA issues special conditions, as
defined in 14 CFR 11.19, in accordance
with § 11.38, and they become part of
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Fmt 4702
Sfmt 4702
25649
the type certification basis under
§ 21.17(a)(2).
Novel or Unusual Design Features
The GVI will have high bypass
engines. Engines of this size,
configuration, and failure modes were
not envisioned when § 25.361, which
addresses loads imposed by engine
seizure, was adopted in 1965. Worst
case engine seizure events have become
increasingly more severe with
increasing engine size because of the
higher inertia of the rotating
components. The GVI engines are
sufficiently different and novel to justify
issuance of a special condition to
establish appropriate design standards.
Discussion of Proposed Special
Conditions
Section 25.361(b)(1) requires that for
turbine engine installations, the engine
mounts and the supporting structures
must be designed to withstand a ‘‘limit
engine torque load imposed by sudden
engine stoppage due to malfunction or
structural failure.’’ Limit loads are
expected to occur about once in the
lifetime of any airplane. Section 25.305
requires that supporting structures be
able to support limit loads without
detrimental permanent deformation,
meaning that supporting structures
should remain serviceable after a limit
load event.
Since adoption of § 25.361(b)(1), the
size, configuration, and failure modes of
jet engines have changed considerably.
Current engines are much larger and are
designed with large bypass fans. In the
event of a structural failure, these
engines are capable of producing much
higher transient loads on the engine
mounts and supporting structures.
As a result, modern high bypass
engines are subject to certain rare-butsevere engine seizure events. Service
history shows that such events occur far
less frequently than limit load events.
Although it is important for the airplane
to be able to support such rare loads
safely without failure, it is unrealistic to
expect that no permanent deformation
will occur.
Given this situation, Aviation
Rulemaking Advisory Committee
(ARAC) has proposed a design standard
for today’s large engines. For the
commonly-occurring deceleration
events, the proposed standard would
require engine mounts and structures to
support maximum torques without
detrimental permanent deformation. For
the rare-but-severe engine seizure events
such as loss of any fan, compressor, or
turbine blade, the proposed standard
would require engine mounts and
structures to support maximum torques
E:\FR\FM\05MYP1.SGM
05MYP1
25650
Federal Register / Vol. 76, No. 87 / Thursday, May 5, 2011 / Proposed Rules
without failure, but allows for some
deformation in the structure.
The FAA concludes that modern large
engines, including those on the GVI, are
novel and unusual compared to those
envisioned when § 25.361(b)(1) was
adopted and thus warrant special
conditions. The proposed special
conditions contain design criteria
recommended by ARAC. The proposed
special conditions also clarify the
design criteria that apply to auxiliary
power units.
Applicability
As discussed above, these proposed
special conditions are applicable to the
GVI. Should Gulfstream apply at a later
date for a change to the type certificate
to include another model incorporating
the same novel or unusual design
features, these proposed special
conditions would apply to that model as
well.
Conclusion
This action affects only certain novel
or unusual design features of the GVI. It
is not a rule of general applicability.
List of Subjects in 14 CFR Part 25
Aircraft, Aviation safety, Reporting
and recordkeeping requirements.
The authority citation for these
special conditions is as follows:
BILLING CODE 4910–13–P
DEPARTMENT OF EDUCATION
emcdonald on DSK2BSOYB1PROD with PROPOSALS
The Proposed Special Conditions
Accordingly, the Federal Aviation
Administration (FAA) proposes the
following special conditions as part of
the type certification basis for the GVI
airplanes.
In lieu of § 25.361(b) the following
special conditions are proposed:
1. For turbine engine installations, the
engine mounts, pylons and adjacent
supporting airframe structure must be
designed to withstand 1g level flight
loads acting simultaneously with the
maximum limit torque loads imposed
by each of the following:
(a) Sudden engine deceleration due to
a malfunction which could result in a
temporary loss of power or thrust; and
(b) The maximum acceleration of the
engine.
2. For auxiliary power unit
installations, the power unit mounts
and adjacent supporting airframe
structure must be designed to withstand
1g level flight loads acting
simultaneously with the maximum limit
torque loads imposed by each of the
following:
(a) Sudden auxiliary power unit
deceleration due to malfunction or
structural failure; and
19:33 May 04, 2011
Jkt 223001
Issued in Renton, Washington, on April 20,
2011.
KC Yanamura,
Acting Manager, Transport Airplane
Directorate, Aircraft Certification Service.
[FR Doc. 2011–10922 Filed 5–4–11; 8:45 am]
Authority: 49 U.S.C. 106(g), 40113, 44701,
44702, 44704.
VerDate Mar<15>2010
(b) The maximum acceleration of the
power unit.
3. For engine supporting structure, an
ultimate loading condition must be
considered that combines 1g flight loads
with the transient dynamic loads
resulting from:
(a) The loss of any fan, compressor, or
turbine blade; and
(b) Separately, where applicable to a
specific engine design, any other engine
structural failure that results in higher
loads.
4. The ultimate loads developed from
the conditions specified in paragraphs
3(a) and 3(b) are to be multiplied by a
factor of 1.0 when applied to engine
mounts and pylons and multiplied by a
factor of 1.25 when applied to adjacent
supporting airframe structure.
5. Any permanent deformation that
results from the conditions specified in
paragraph 3 must not prevent continued
safe flight and landing.
34 CFR Chapter VI
[Docket ID ED–2011–OPE–0003]
Negotiated Rulemaking Committees;
Public Hearings
Office of Postsecondary
Education, Department of Education.
ACTION: Intent to establish negotiated
rulemaking committees.
AGENCY:
We announce our intention to
establish one or more negotiated
rulemaking committees to propose
regulations under the Higher Education
Act of 1965, as amended (HEA). The
committees will include representatives
of organizations or groups with interests
that are significantly affected by the
subject matter of the proposed
regulations, as described more fully in
the Regulatory Issues section of this
document. We also announce three
public hearings, at which interested
parties may suggest additional issues
that should be considered for action by
the negotiating committees. In addition,
for anyone unable to attend a public
hearing, we announce that the
Department will accept written
comments.
Finally, the Department announces
that it will conduct roundtable
SUMMARY:
PO 00000
Frm 00039
Fmt 4702
Sfmt 4702
discussions that focus on the areas of
teacher preparation, college completion,
and the Department’s proposed ‘‘First in
the World’’ competition, as more fully
described in the Roundtable Discussions
section of this document.
DATES: The dates, times, and locations
of the public hearings and the
roundtable discussions are listed under
the SUPPLEMENTARY INFORMATION section
of this notice. We must receive written
comments suggesting issues that should
be considered for action by the
negotiating committees on or before
May 20, 2011.
ADDRESSES: Submit your comments
through the Federal eRulemaking Portal
or via postal mail, commercial delivery,
or hand delivery. We will not accept
comments by fax or by e-mail. Please
submit your comments only one time, in
order to ensure that we do not receive
duplicate copies. In addition, please
include the Docket ID at the top of your
comments.
• Federal eRulemaking Portal: Go to
www.regulations.gov to submit your
comments electronically. Information
on using Regulations.gov, including
instructions for finding a notice,
submitting a comment, finding a
comment, and signing up for e-mail
alerts, is available on the site under
‘‘How to Use Regulations.gov’’ in the
Help section.
• Postal Mail, Commercial Delivery,
or Hand Delivery. If you mail or deliver
your comments about these proposed
regulations, address them to Nikki
Harris, U.S. Department of Education,
1990 K Street, NW., room 8033,
Washington, DC 20006.
Privacy Note: The Department’s policy for
comments received from members of the
public (including those comments submitted
by mail, commercial delivery, or hand
delivery) is to make these submissions
available for public viewing in their entirety
on the Federal eRulemaking Portal at
www.regulations.gov. Therefore, commenters
should be careful to include in their
comments only information that they wish to
make publicly available on the Internet.
For
information about the public hearings
and roundtable discussions, go to
https://www2.ed.gov/policy/highered/
reg/hearulemaking/2011/hearings.html
or contact: Nikki Harris, U.S.
Department of Education, 1990 K Street,
NW., room 8033, Washington, DC
20006. Telephone: (202) 219–7050. You
may also e-mail your questions about
the public hearings to:
negreg.2011@ed.gov.
For information about negotiated
rulemaking in general, go to The
Negotiated Rulemaking Process for Title
FOR FURTHER INFORMATION CONTACT:
E:\FR\FM\05MYP1.SGM
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]]>Agencies
[Federal Register Volume 76, Number 87 (Thursday, May 5, 2011)]
[Proposed Rules]
[Pages 25648-25650]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-10922]
=======================================================================
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. NM454 Special Conditions No. 25-11-11-SC]
Special Conditions: Gulfstream Model GVI Airplane; Limit Engine
Torque Loads for Sudden Engine Stoppage
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed special conditions.
-----------------------------------------------------------------------
SUMMARY: This action proposes special conditions for the Gulfstream GVI
airplane. This airplane will have novel or unusual design features when
compared to the state of technology envisioned in the airworthiness
standards for transport category airplanes. These design features
include
[[Page 25649]]
engine size and the potential torque load imposed by sudden engine
stoppage. These proposed special conditions pertain to their effects on
the structural performance of the airplane. The applicable
airworthiness regulations do not contain adequate or appropriate safety
standards for these design features. These proposed special conditions
contain the additional safety standards that the Administrator
considers necessary to establish a level of safety equivalent to that
established by the existing airworthiness standards.
DATES: We must receive your comments by June 20, 2011.
ADDRESSES: You must mail two copies of your comments to: Federal
Aviation Administration, Transport Airplane Directorate, Attn: Rules
Docket (ANM-113), Docket No. NM454, 1601 Lind Avenue SW., Renton,
Washington 98057-3356. You may deliver two copies to the Transport
Airplane Directorate at the above address. You must mark your comments:
Docket No. NM454. You can inspect comments in the Rules Docket
weekdays, except Federal holidays, between 7:30 a.m. and 4 p.m.
FOR FURTHER INFORMATION CONTACT: Carl Niedermeyer, FAA, Airframe/Cabin
Safety Branch, ANM-115, Transport Standards Staff, Transport Airplane
Directorate, Aircraft Certification Service, 1601 Lind Avenue SW.,
Renton, Washington 98057-3356; telephone (425) 227-2279; electronic
mail Carl.Neidermeyer@faa.gov.
SUPPLEMENTARY INFORMATION:
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 file in the docket all comments we receive, as well as a
report summarizing each substantive public contact with FAA personnel
concerning these special conditions. You can inspect the docket before
and after the comment closing date. If you wish to review the docket in
person, go to the address in the ADDRESSES section of this preamble
between 7:30 a.m. and 4 p.m., Monday through Friday, except Federal
holidays.
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.
If you want us to acknowledge receipt of your comments on this
proposal, include with your comments a self-addressed, stamped postcard
on which you have written the docket number. We will stamp the date on
the postcard and mail it back to you.
Background
On March 29, 2005, Gulfstream Aerospace Corporation (hereafter
referred to as ``Gulfstream'') applied for an FAA type certificate for
its new Gulfstream Model GVI passenger airplane. Gulfstream later
applied for, and was granted, an extension of time for the type
certificate, which changed the effective application date to September
28, 2006. The Gulfstream Model GVI airplane will be an all-new, two-
engine jet transport airplane with an executive cabin interior. The
maximum takeoff weight will be 99,600 pounds, with a maximum passenger
count of 19 passengers.
Type Certification Basis
Under provisions of Title 14, Code of Federal Regulations (14 CFR)
21.17, Gulfstream must show that the Gulfstream Model GVI airplane
(hereafter referred to as ``the GVI'') meets the applicable provisions
of 14 CFR part 25, as amended by Amendments 25-1 through 25-119, 25-
122, and 25.124. If the Administrator finds that the applicable
airworthiness regulations (i.e., 14 CFR part 25) do not contain
adequate or appropriate safety standards for the GVI because of a novel
or unusual design feature, special conditions are prescribed under the
provisions of Sec. 21.16.
Special conditions are initially applicable to the 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 features, the special conditions would also apply to the
other model under provisions of Sec. 21.101.
In addition to complying with the applicable airworthiness
regulations and special conditions, the GVI 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 must also issue a
finding of regulatory adequacy pursuant to section 611 of Public Law
92-574, the ``Noise Control Act of 1972.''
The FAA issues special conditions, as defined in 14 CFR 11.19, in
accordance with Sec. 11.38, and they become part of the type
certification basis under Sec. 21.17(a)(2).
Novel or Unusual Design Features
The GVI will have high bypass engines. Engines of this size,
configuration, and failure modes were not envisioned when Sec. 25.361,
which addresses loads imposed by engine seizure, was adopted in 1965.
Worst case engine seizure events have become increasingly more severe
with increasing engine size because of the higher inertia of the
rotating components. The GVI engines are sufficiently different and
novel to justify issuance of a special condition to establish
appropriate design standards.
Discussion of Proposed Special Conditions
Section 25.361(b)(1) requires that for turbine engine
installations, the engine mounts and the supporting structures must be
designed to withstand a ``limit engine torque load imposed by sudden
engine stoppage due to malfunction or structural failure.'' Limit loads
are expected to occur about once in the lifetime of any airplane.
Section 25.305 requires that supporting structures be able to support
limit loads without detrimental permanent deformation, meaning that
supporting structures should remain serviceable after a limit load
event.
Since adoption of Sec. 25.361(b)(1), the size, configuration, and
failure modes of jet engines have changed considerably. Current engines
are much larger and are designed with large bypass fans. In the event
of a structural failure, these engines are capable of producing much
higher transient loads on the engine mounts and supporting structures.
As a result, modern high bypass engines are subject to certain
rare-but-severe engine seizure events. Service history shows that such
events occur far less frequently than limit load events. Although it is
important for the airplane to be able to support such rare loads safely
without failure, it is unrealistic to expect that no permanent
deformation will occur.
Given this situation, Aviation Rulemaking Advisory Committee (ARAC)
has proposed a design standard for today's large engines. For the
commonly-occurring deceleration events, the proposed standard would
require engine mounts and structures to support maximum torques without
detrimental permanent deformation. For the rare-but-severe engine
seizure events such as loss of any fan, compressor, or turbine blade,
the proposed standard would require engine mounts and structures to
support maximum torques
[[Page 25650]]
without failure, but allows for some deformation in the structure.
The FAA concludes that modern large engines, including those on the
GVI, are novel and unusual compared to those envisioned when Sec.
25.361(b)(1) was adopted and thus warrant special conditions. The
proposed special conditions contain design criteria recommended by
ARAC. The proposed special conditions also clarify the design criteria
that apply to auxiliary power units.
Applicability
As discussed above, these proposed special conditions are
applicable to the GVI. Should Gulfstream apply at a later date for a
change to the type certificate to include another model incorporating
the same novel or unusual design features, these proposed special
conditions would apply to that model as well.
Conclusion
This action affects only certain novel or unusual design features
of the GVI. It is not a rule of general applicability.
List of Subjects in 14 CFR Part 25
Aircraft, Aviation safety, Reporting and recordkeeping
requirements.
The authority citation for these special conditions is as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, 44704.
The Proposed Special Conditions
Accordingly, the Federal Aviation Administration (FAA) proposes the
following special conditions as part of the type certification basis
for the GVI airplanes.
In lieu of Sec. 25.361(b) the following special conditions are
proposed:
1. For turbine engine installations, the engine mounts, pylons and
adjacent supporting airframe structure must be designed to withstand 1g
level flight loads acting simultaneously with the maximum limit torque
loads imposed by each of the following:
(a) Sudden engine deceleration due to a malfunction which could
result in a temporary loss of power or thrust; and
(b) The maximum acceleration of the engine.
2. For auxiliary power unit installations, the power unit mounts
and adjacent supporting airframe structure must be designed to
withstand 1g level flight loads acting simultaneously with the maximum
limit torque loads imposed by each of the following:
(a) Sudden auxiliary power unit deceleration due to malfunction or
structural failure; and
(b) The maximum acceleration of the power unit.
3. For engine supporting structure, an ultimate loading condition
must be considered that combines 1g flight loads with the transient
dynamic loads resulting from:
(a) The loss of any fan, compressor, or turbine blade; and
(b) Separately, where applicable to a specific engine design, any
other engine structural failure that results in higher loads.
4. The ultimate loads developed from the conditions specified in
paragraphs 3(a) and 3(b) are to be multiplied by a factor of 1.0 when
applied to engine mounts and pylons and multiplied by a factor of 1.25
when applied to adjacent supporting airframe structure.
5. Any permanent deformation that results from the conditions
specified in paragraph 3 must not prevent continued safe flight and
landing.
Issued in Renton, Washington, on April 20, 2011.
KC Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2011-10922 Filed 5-4-11; 8:45 am]
BILLING CODE 4910-13-P
