Special Conditions: Airbus Model A380-800 Airplane, Discrete Gust Requirements, 46113-46115 [05-15659]
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Federal Register / Vol. 70, No. 152 / Tuesday, August 9, 2005 / Proposed Rules
the Model A380–800 has been moved
from May 2005, to January 2006, to
match the delivery date of the first
production airplane. In accordance with
14 CFR 21.17(d)(2), Airbus chose a new
application date of April 20, 1999, and
requested that the 7-year certification
period which had already been
approved be continued. The part 25
certification basis for the Model A380–
800 airplane was adjusted to reflect the
new application date.
The Model A380–800 airplane will be
an all-new, four-engine jet transport
airplane with a full double-deck, twoaisle cabin. The maximum takeoff
weight will be 1.235 million pounds
with a typical three-class layout of 555
passengers.
Type Certification Basis
Under the provisions of 14 CFR 21.17,
Airbus must show that the Model A380–
800 airplane meets the applicable
provisions of 14 CFR part 25, as
amended by Amendments 25–1 through
25–98. If the Administrator finds that
the applicable airworthiness regulations
do not contain adequate or appropriate
safety standards for the Airbus A380–
800 airplane because of novel or
unusual design features, special
conditions are prescribed under the
provisions of 14 CFR 21.16.
In addition to the applicable
airworthiness regulations and special
conditions, the Airbus Model A380–800
airplane must comply with the fuel vent
and exhaust emission requirements of
14 CFR part 34 and the noise
certification requirements of 14 CFR
part 36. In addition, the FAA must issue
a finding of regulatory adequacy
pursuant to section 611 of Public Law
93–574, the ‘‘Noise Control Act of
1972.’’
Special conditions, as defined in 14
CFR 11.19, are issued in accordance
with 14 CFR 11.38 and become part of
the type certification basis in
accordance with 14 CFR 21.17(a)(2),
Amendment 21–69, effective September
16, 1991.
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, or should any other
model already included on the same
type certificate be modified to
incorporate the same novel or unusual
design features, the special conditions
would also apply to the other model
under the provisions of 14 CFR
21.101(a)(1), Amendment 21–69,
effective September 16, 1991.
VerDate jul<14>2003
15:10 Aug 08, 2005
Jkt 205001
Discussion of Novel or Unusual Design
Features
Emergency evacuations are generally
associated with adverse conditions,
such as a fire outside the airplane.
Because those adverse conditions may
pose an immediate threat to the
occupants of the airplane, it is often
necessary to avoid opening emergency
exits that would otherwise be usable.
For this reason, it would be extremely
useful to have a viewing window or
other means of assessing the outside
conditions to determine whether to
open a particular emergency exit.
The regulations governing the
certification of the A380 do not
adequately address a full-length double
deck airplane in terms of the exit of
passengers in an emergency and a
viewing window or other means of
assessing the outside conditions to
determine whether to open an
emergency exit. Therefore, the FAA is
proposing special conditions to ensure
that each emergency exit has a means to
permit viewing of the conditions
outside the exit when the exit is closed.
These special conditions are based upon
Notice of Proposed Rulemaking (NPRM)
96–9 and Amendment 25–116, effective
November 26, 2004, which adopted a
similar requirement into § 25.809(a).
Applicability
As discussed above, these special
conditions are applicable to the Airbus
A380–800 airplane. Should Airbus
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 special
conditions would apply to that model as
well under the provisions of
§ 21.101(a)(1), Amendment 21–69,
effective September 16, 1991.
Conclusion
This action affects only certain novel
or unusual design features of the Airbus
A380–800 airplane. It is not a rule of
general applicability, and it affects only
the applicant which applied to the FAA
for approval of these features on the
airplane.
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, pursuant to the
authority delegated to me by the
Administrator, the Federal Aviation
PO 00000
Frm 00015
Fmt 4702
Sfmt 4702
46113
Administration (FAA) proposes the
following special conditions as part of
the type certification basis for the
Airbus A380–800 airplane.
In addition to the requirements of
§ 25.809(a), the following special
conditions apply:
Each emergency exit must have means
to permit viewing of the conditions
outside the exit when the exit is closed.
The viewing means may be on the exit
or adjacent to it, provided that no
obstructions exist between the exit and
the viewing means. Means must also be
provided to permit viewing of the likely
areas of evacuee ground contact with
the landing gear extended as well as in
all conditions of landing gear collapse.
A single device that satisfies both
objectives is acceptable.
Issued in Renton, Washington, on July 19,
2005.
Ali Bahrami,
Manager, Transport Airplane Directorate,
Aircraft Certification Service.
[FR Doc. 05–15658 Filed 8–8–05; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. NM316; Notice No. 25–05–11–
SC]
Special Conditions: Airbus Model
A380–800 Airplane, Discrete Gust
Requirements
Federal Aviation
Administration (FAA), DOT.
ACTION: Notice of proposed special
conditions.
AGENCY:
SUMMARY: This notice proposes special
conditions for the Airbus A380–800
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. Many of these novel or
unusual design features are associated
with the complex systems and the
configuration of the airplane, including
its full-length double deck. For these
design features, the applicable
airworthiness regulations do not contain
adequate or appropriate safety standards
regarding discrete gust requirements.
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.
Additional special conditions will be
E:\FR\FM\09AUP1.SGM
09AUP1
46114
Federal Register / Vol. 70, No. 152 / Tuesday, August 9, 2005 / Proposed Rules
issued for other novel or unusual design
features of the Airbus Model A380–800
airplane.
DATES: Comments must be received on
or before September 23, 2005.
ADDRESSES: Comments on this proposal
may be mailed in duplicate to: Federal
Aviation Administration, Transport
Airplane Directorate, Attention: Rules
Docket (ANM–113), Docket No. NM316,
1601 Lind Avenue SW., Renton,
Washington 98055–4056; or delivered in
duplicate to the Transport Airplane
Directorate at the above address. All
comments must be marked: Docket No.
NM316. 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:
Holly Thorson, FAA, International
Branch, ANM–116, Transport Airplane
Directorate, Aircraft Certification
Service, 1601 Lind Avenue SW.,
Renton, Washington 98055–4056;
telephone (425) 227–1357; facsimile
(425) 227–1149.
SUPPLEMENTARY INFORMATION:
Comments Invited
The FAA invites interested persons to
participate in this rulemaking by
submitting 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 proposed special conditions. The
docket is available for public inspection
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 notice
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 the proposed special
conditions in light of the comments we
receive.
If you want the FAA to acknowledge
receipt of your comments on this
proposal, include with your comments
a pre-addressed, stamped postcard on
which the docket number appears. We
will stamp the date on the postcard and
mail it back to you.
VerDate jul<14>2003
15:10 Aug 08, 2005
Jkt 205001
Background
Airbus applied for FAA certification/
validation of the provisionallydesignated Model A3XX–100 in its
letter AI/L 810.0223/98, dated August
12, 1998, to the FAA. Application for
certification by the Joint Aviation
Authorities (JAA) of Europe had been
made on January 16, 1998, reference AI/
L 810.0019/98. In its letter to the FAA,
Airbus requested an extension to the 5year period for type certification in
accordance with 14 CFR 21.17(c). The
request was for an extension to a 7-year
period, using the date of the initial
application letter to the JAA as the
reference date. The reason given by
Airbus for the request for extension is
related to the technical challenges,
complexity, and the number of new and
novel features on the airplane. On
November 12, 1998, the Manager,
Aircraft Engineering Division, AIR–100,
granted Airbus’ request for the 7-year
period, based on the date of application
to the JAA.
In its letter AI/LE–A 828.0040/99
Issue 3, dated July 20, 2001, Airbus
stated that its target date for type
certification of the Model A380–800 has
been moved from May 2005, to January
2006, to match the delivery date of the
first production airplane. In accordance
with 14 CFR 21.17(d)(2), Airbus chose a
new application date of April 20, 1999,
and requested that the 7-year
certification period which had already
been approved be continued. The part
25 certification basis for the Model
A380–800 airplane was adjusted to
reflect the new application date.
The Model A380–800 airplane will be
an all-new, four-engine jet transport
airplane with a full double-deck, twoaisle cabin. The maximum takeoff
weight will be 1.235 million pounds
with a typical three-class layout of 555
passengers.
Type Certification Basis
Under the provisions of 14 CFR 21.17,
Airbus must show that the Model A380–
800 airplane meets the applicable
provisions of 14 CFR part 25, as
amended by Amendments 25–1 through
25–98. If the Administrator finds that
the applicable airworthiness regulations
do not contain adequate or appropriate
safety standards for the Airbus A380–
800 airplane because of novel or
unusual design features, special
conditions are prescribed under the
provisions of 14 CFR 21.16.
In addition to the applicable
airworthiness regulations and special
conditions, the Airbus Model A380–800
airplane must comply with the fuel vent
and exhaust emission requirements of
PO 00000
Frm 00016
Fmt 4702
Sfmt 4702
14 CFR part 34 and the noise
certification requirements of 14 CFR
part 36. In addition, the FAA must issue
a finding of regulatory adequacy
pursuant to section 611 of Public Law
93–574, the ‘‘Noise Control Act of
1972.’’
Special conditions, as defined in 14
CFR 11.19, are issued in accordance
with 14 CFR 11.38 and become part of
the type certification basis in
accordance with 14 CFR 21.17(a)(2),
Amendment 21–69, effective September
16, 1991.
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, or should any other
model already included on the same
type certificate be modified to
incorporate the same novel or unusual
design features, the special conditions
would also apply to the other model
under the provisions of 14 CFR
21.101(a)(1), Amendment 21–69,
effective September 16, 1991.
Discussion of Novel or Unusual Design
Features
In terms of discrete gust requirements,
the size of the Airbus Model A380 is a
novel or unusual design feature. These
requirements are found in 14 CFR
25.341 (Amendment 25–86) which
specifies that the gust loads acting on
the airplane are to be determined by
dynamic analysis, considering the
dynamic and rigid body responses of the
airplane. Section 25.341(a)(3) requires
that a sufficient number of gust gradient
distances in the range of 30 feet to 350
feet be investigated to find the critical
response for each load quantity. For
large airplanes, the longer gust gradient
distances are vital to assess the rigid
body response.
At the time § 25.341 was adopted, the
value of the upper end of the range of
gust gradient distances to be
investigated was determined from the
largest commercial airplane then in
existence, the Boeing Model 747. This
value was calculated to be the mean
geometric chord of the Boeing 747
(which is 28 feet) multiplied by 12.5,
which equals 350 feet.
Since the mean geometric chord of the
A380 is larger than that of the Boeing
747, a special condition is necessary to
define an appropriate upper value for
the range of gust gradient distances to be
investigated. That value would be the
mean geometric chord of the A380
(which is 34.8 feet) multiplied by 12.5,
which equals 435 feet. Increasing the
range of gust gradient distances to be
E:\FR\FM\09AUP1.SGM
09AUP1
Federal Register / Vol. 70, No. 152 / Tuesday, August 9, 2005 / Proposed Rules
investigated to 435 feet will ensure an
appropriate analysis of the critical rigid
body response of the A380.
DEPARTMENT OF TRANSPORTATION
Applicability
14 CFR Part 25
As discussed above, these special
conditions are applicable to the Airbus
A380–800 airplane. Should Airbus
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 special
conditions would apply to that model as
well under the provisions of
§ 21.101(a)(1), Amendment 21–69,
effective September 16, 1991.
Conclusion
This action affects only certain novel
or unusual design features of the Airbus
A380–800 airplane. It is not a rule of
general applicability, and it affects only
the applicant which applied to the FAA
for approval of these features on the
airplane.
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, pursuant to the
authority delegated to me by the
Administrator, the Federal Aviation
Administration (FAA) proposes the
following special conditions as part of
the type certification basis for the
Airbus A380–800 airplane.
In lieu of the requirements of
§ 25.341(a)(3), the following special
conditions apply:
A sufficient number of gust gradient
distances in the range of 30 feet to 435
feet (12.5 times the Geometric Mean
Chord of the Model A380) must be
investigated to find the critical response
for each load quantity.
Issued in Renton, Washington, on July 19,
2005.
Ali Bahrami,
Manager, Transport Airplane Directorate,
Aircraft Certification Service.
[FR Doc. 05–15659 Filed 8–8–05; 8:45 am]
BILLING CODE 4910–13–P
VerDate jul<14>2003
15:10 Aug 08, 2005
Jkt 205001
Federal Aviation Administration
[Docket No. NM317; Notice No. 25–05–12–
SC]
Special Conditions: Airbus Model
A380–800 Airplane, Flotation and
Ditching
Federal Aviation
Administration (FAA), DOT.
ACTION: Notice of proposed special
conditions.
AGENCY:
SUMMARY: This notice proposes special
conditions for the Airbus A380–800
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. Many of these novel or
unusual design features are associated
with the complex systems and the
configuration of the airplane, including
its full-length double deck. For these
design features, the applicable
airworthiness regulations do not contain
adequate or appropriate safety standards
regarding flotation and ditching. 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. Additional
special conditions will be issued for
other novel or unusual design features
of the Airbus Model A380–800 airplane.
DATES: Comments must be received on
or before September 23, 2005.
ADDRESSES: Comments on this proposal
may be mailed in duplicate to: Federal
Aviation Administration, Transport
Airplane Directorate, Attention: Rules
Docket (ANM–113), Docket No. NM317,
1601 Lind Avenue SW., Renton,
Washington 98055–4056; or delivered in
duplicate to the Transport Airplane
Directorate at the above address. All
comments must be marked: Docket No.
NM317. 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:
Holly Thorson, FAA, International
Branch, ANM–116, Transport Airplane
Directorate, Aircraft Certification
Service, 1601 Lind Avenue SW.,
Renton, Washington 98055–4056;
telephone (425) 227–1357; facsimile
(425) 227–1149.
SUPPLEMENTARY INFORMATION:
PO 00000
Frm 00017
Fmt 4702
Sfmt 4702
46115
Comments Invited
The FAA invites interested persons to
participate in this rulemaking by
submitting 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 proposed special conditions. The
docket is available for public inspection
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 notice
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 the proposed special
conditions in light of the comments we
receive.
If you want the FAA to acknowledge
receipt of your comments on this
proposal, include with your comments
a pre-addressed, stamped postcard on
which the docket number appears. We
will stamp the date on the postcard and
mail it back to you.
Background
Airbus applied for FAA certification/
validation of the provisionallydesignated Model A3XX–100 in its
letter AI/L 810.0223/98, dated August
12, 1998, to the FAA. Application for
certification by the Joint Aviation
Authorities (JAA) of Europe had been
made on January 16, 1998, reference
AI/L 810.0019/98. In its letter to the
FAA, Airbus requested an extension to
the 5-year period for type certification
in accordance with 14 CFR 21.17(c). The
request was for an extension to a 7-year
period, using the date of the initial
application letter to the JAA as the
reference date. The reason given by
Airbus for the request for extension is
related to the technical challenges,
complexity, and the number of new and
novel features on the airplane. On
November 12, 1998, the Manager,
Aircraft Engineering Division, AIR–100,
granted Airbus’ request for the 7-year
period, based on the date of application
to the JAA.
In its letter AI/LE–A 828.0040/99
Issue 3, dated July 20, 2001, Airbus
stated that its target date for type
E:\FR\FM\09AUP1.SGM
09AUP1
Agencies
[Federal Register Volume 70, Number 152 (Tuesday, August 9, 2005)]
[Proposed Rules]
[Pages 46113-46115]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-15659]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. NM316; Notice No. 25-05-11-SC]
Special Conditions: Airbus Model A380-800 Airplane, Discrete Gust
Requirements
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed special conditions.
-----------------------------------------------------------------------
SUMMARY: This notice proposes special conditions for the Airbus A380-
800 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. Many of these
novel or unusual design features are associated with the complex
systems and the configuration of the airplane, including its full-
length double deck. For these design features, the applicable
airworthiness regulations do not contain adequate or appropriate safety
standards regarding discrete gust requirements. 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.
Additional special conditions will be
[[Page 46114]]
issued for other novel or unusual design features of the Airbus Model
A380-800 airplane.
DATES: Comments must be received on or before September 23, 2005.
ADDRESSES: Comments on this proposal may be mailed in duplicate to:
Federal Aviation Administration, Transport Airplane Directorate,
Attention: Rules Docket (ANM-113), Docket No. NM316, 1601 Lind Avenue
SW., Renton, Washington 98055-4056; or delivered in duplicate to the
Transport Airplane Directorate at the above address. All comments must
be marked: Docket No. NM316. 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: Holly Thorson, FAA, International
Branch, ANM-116, Transport Airplane Directorate, Aircraft Certification
Service, 1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone
(425) 227-1357; facsimile (425) 227-1149.
SUPPLEMENTARY INFORMATION:
Comments Invited
The FAA invites interested persons to participate in this
rulemaking by submitting 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 proposed special conditions. The docket is available
for public inspection 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 notice 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 the
proposed special conditions in light of the comments we receive.
If you want the FAA to acknowledge receipt of your comments on this
proposal, include with your comments a pre-addressed, stamped postcard
on which the docket number appears. We will stamp the date on the
postcard and mail it back to you.
Background
Airbus applied for FAA certification/validation of the
provisionally-designated Model A3XX-100 in its letter AI/L 810.0223/98,
dated August 12, 1998, to the FAA. Application for certification by the
Joint Aviation Authorities (JAA) of Europe had been made on January 16,
1998, reference AI/L 810.0019/98. In its letter to the FAA, Airbus
requested an extension to the 5-year period for type certification in
accordance with 14 CFR 21.17(c). The request was for an extension to a
7-year period, using the date of the initial application letter to the
JAA as the reference date. The reason given by Airbus for the request
for extension is related to the technical challenges, complexity, and
the number of new and novel features on the airplane. On November 12,
1998, the Manager, Aircraft Engineering Division, AIR-100, granted
Airbus' request for the 7-year period, based on the date of application
to the JAA.
In its letter AI/LE-A 828.0040/99 Issue 3, dated July 20, 2001,
Airbus stated that its target date for type certification of the Model
A380-800 has been moved from May 2005, to January 2006, to match the
delivery date of the first production airplane. In accordance with 14
CFR 21.17(d)(2), Airbus chose a new application date of April 20, 1999,
and requested that the 7-year certification period which had already
been approved be continued. The part 25 certification basis for the
Model A380-800 airplane was adjusted to reflect the new application
date.
The Model A380-800 airplane will be an all-new, four-engine jet
transport airplane with a full double-deck, two-aisle cabin. The
maximum takeoff weight will be 1.235 million pounds with a typical
three-class layout of 555 passengers.
Type Certification Basis
Under the provisions of 14 CFR 21.17, Airbus must show that the
Model A380-800 airplane meets the applicable provisions of 14 CFR part
25, as amended by Amendments 25-1 through 25-98. If the Administrator
finds that the applicable airworthiness regulations do not contain
adequate or appropriate safety standards for the Airbus A380-800
airplane because of novel or unusual design features, special
conditions are prescribed under the provisions of 14 CFR 21.16.
In addition to the applicable airworthiness regulations and special
conditions, the Airbus Model A380-800 airplane must comply with the
fuel vent and exhaust emission requirements of 14 CFR part 34 and the
noise certification requirements of 14 CFR part 36. In addition, the
FAA must issue a finding of regulatory adequacy pursuant to section 611
of Public Law 93-574, the ``Noise Control Act of 1972.''
Special conditions, as defined in 14 CFR 11.19, are issued in
accordance with 14 CFR 11.38 and become part of the type certification
basis in accordance with 14 CFR 21.17(a)(2), Amendment 21-69, effective
September 16, 1991.
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, or should any other model already included on
the same type certificate be modified to incorporate the same novel or
unusual design features, the special conditions would also apply to the
other model under the provisions of 14 CFR 21.101(a)(1), Amendment 21-
69, effective September 16, 1991.
Discussion of Novel or Unusual Design Features
In terms of discrete gust requirements, the size of the Airbus
Model A380 is a novel or unusual design feature. These requirements are
found in 14 CFR 25.341 (Amendment 25-86) which specifies that the gust
loads acting on the airplane are to be determined by dynamic analysis,
considering the dynamic and rigid body responses of the airplane.
Section 25.341(a)(3) requires that a sufficient number of gust gradient
distances in the range of 30 feet to 350 feet be investigated to find
the critical response for each load quantity. For large airplanes, the
longer gust gradient distances are vital to assess the rigid body
response.
At the time Sec. 25.341 was adopted, the value of the upper end of
the range of gust gradient distances to be investigated was determined
from the largest commercial airplane then in existence, the Boeing
Model 747. This value was calculated to be the mean geometric chord of
the Boeing 747 (which is 28 feet) multiplied by 12.5, which equals 350
feet.
Since the mean geometric chord of the A380 is larger than that of
the Boeing 747, a special condition is necessary to define an
appropriate upper value for the range of gust gradient distances to be
investigated. That value would be the mean geometric chord of the A380
(which is 34.8 feet) multiplied by 12.5, which equals 435 feet.
Increasing the range of gust gradient distances to be
[[Page 46115]]
investigated to 435 feet will ensure an appropriate analysis of the
critical rigid body response of the A380.
Applicability
As discussed above, these special conditions are applicable to the
Airbus A380-800 airplane. Should Airbus 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 special conditions
would apply to that model as well under the provisions of Sec.
21.101(a)(1), Amendment 21-69, effective September 16, 1991.
Conclusion
This action affects only certain novel or unusual design features
of the Airbus A380-800 airplane. It is not a rule of general
applicability, and it affects only the applicant which applied to the
FAA for approval of these features on the airplane.
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, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration (FAA) proposes the
following special conditions as part of the type certification basis
for the Airbus A380-800 airplane.
In lieu of the requirements of Sec. 25.341(a)(3), the following
special conditions apply:
A sufficient number of gust gradient distances in the range of 30
feet to 435 feet (12.5 times the Geometric Mean Chord of the Model
A380) must be investigated to find the critical response for each load
quantity.
Issued in Renton, Washington, on July 19, 2005.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 05-15659 Filed 8-8-05; 8:45 am]
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