Special Conditions: The Boeing Company Model 787-10 Airplane; Aeroelastic Stability Requirements, Flaps-Up Vertical Modal-Suppression System, 14115-14117 [2017-05326]
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Federal Register / Vol. 82, No. 51 / Friday, March 17, 2017 / Rules and Regulations
and all adverse impacts upon, airplane
equipment, systems, networks, or other
assets required for safe flight and
operations.
2. The applicant must establish
appropriate procedures to allow the
operator to ensure that continued
airworthiness of the airplane is
maintained, including all post-typecertification modifications that may
have an impact on the approved
electronic-system security safeguards.
Issued in Renton, Washington, on February
10, 2017.
Michael Kaszycki,
Assistant Manager, Transport Airplane
Directorate, Aircraft Certification Service.
[FR Doc. 2017–05333 Filed 3–16–17; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA–2016–6137; Special
Conditions No. 25–644–SC]
Special Conditions: The Boeing
Company Model 787–10 Airplane;
Aeroelastic Stability Requirements,
Flaps-Up Vertical Modal-Suppression
System
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions.
AGENCY:
These special conditions are
issued for the Boeing Company (Boeing)
Model 787–10 airplane. This airplane
will have a novel or unusual design
feature when compared to the state of
technology envisioned in the
airworthiness standards for transportcategory airplanes. This design feature
is a flaps-up vertical modal-suppression
system, which is in lieu of traditional
methods of improving airplane flutter
characteristics. The applicable
airworthiness regulations do not contain
adequate or appropriate safety standards
for this design feature. These special
conditions contain the additional safety
standards that the Administrator
considers necessary to establish a level
of safety equivalent to that established
by the existing airworthiness standards.
DATES: Effective April 17, 2017.
FOR FURTHER INFORMATION CONTACT:
Wael Nour, FAA, Airframe and Cabin
Safety Branch, ANM–115, Transport
Airplane Directorate, Aircraft
Certification Service, 1601 Lind Avenue
SW., Renton, Washington 98057–3356;
telephone 425–227–2143; facsimile
425–227–1320.
mstockstill on DSK3G9T082PROD with RULES
SUMMARY:
VerDate Sep<11>2014
19:31 Mar 16, 2017
Jkt 241001
SUPPLEMENTARY INFORMATION:
Background
On July 30, 2013, Boeing applied for
an amendment to Type Certificate No.
T00021SE to include the new Model
787–10 airplane. This twin-engine,
transport-category airplane is a
stretched-fuselage derivative of the 787–
9, with maximum seating capacity of
440 passengers. The 787–10 has a
maximum takeoff weight of 560,000 lbs.
Type Certification Basis
Under the provisions of Title 14, Code
of Federal Regulations (14 CFR) 21.101,
Boeing must show that the Model 787–
10 airplane meets the applicable
provisions of the regulations listed in
Type Certificate No. T00021SE or the
applicable regulations in effect on the
date of application for the change,
except for earlier amendments as agreed
upon by the FAA.
In addition, the certification basis
includes other regulations, special
conditions, and exemptions that are not
relevant to these proposed special
conditions. Type Certificate No.
T00021SE will be updated to include a
complete description of the certification
basis for this airplane model.
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 Model 787–10 airplane 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 feature, or should any other
model already included on the same
type certificate be modified to
incorporate the same novel or unusual
design feature, these special conditions
would also apply to the other model
under § 21.101.
In addition to the applicable
airworthiness regulations and special
conditions, the Model 787–10 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.
The FAA issues special conditions, as
defined in 14 CFR 11.19, in accordance
with § 11.38, and they become part of
the type certification basis under
§ 21.101.
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Fmt 4700
Sfmt 4700
14115
Novel or Unusual Design Features
The Model 787–10 airplane will
incorporate the following novel or
unusual design feature:
A flaps-up vertical modal suppression
system.
Discussion
The Boeing Model 787–10 will add a
new flaps-up vertical modalsuppression (F0VMS) system to the
Normal mode of the primary flightcontrol system (PFCS). The F0VMS
system is needed to satisfy the flutterdamping margin requirements of
§ 25.629 and the means-of-compliance
provisions in Advisory Circular (AC)
25.629–1B. This system will be used in
lieu of typical methods of improving the
flutter characteristics of an airplane,
such as increasing the torsional stiffness
of the wing or adding wingtip ballast
weights.
The F0VMS system is an active
modal-suppression system that will
provide additional damping to an
already stable, but low-damped, 3Hz
symmetric wing, nacelle, and body
aeroelastic mode of the airplane. This
feedback-control system will maintain
adequate damping margins to flutter.
The F0VMS system accomplishes this
by oscillating the elevators, and, when
needed, the flaperons.
Because Boeing’s flutter analysis
shows that the 3Hz mode is stable and
does not flutter, the F0VMS system is
not an active flutter-suppression system,
but, rather, a damping-augmentation
system. At this time, the FAA is not
prepared to accept an active fluttersuppression system that suppresses a
divergent flutter mode in the
operational or design envelope of the
airplane.
This will be the first time an active
modal-suppression system will be used
for § 25.629 compliance. The use of this
new active modal-suppression system
for flutter compliance is novel or
unusual when compared to the
technology envisioned in the current
airworthiness standards. Consequently,
special conditions are required in
consideration of the effects of this new
system on the aeroelastic stability of the
airplane, both in the normal and failed
state, to maintain the level of safety
intended by § 25.629.
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.
Discussion of Comments
Notice of Proposed Special
Conditions No. 25–16–05–SC for the
E:\FR\FM\17MRR1.SGM
17MRR1
Federal Register / Vol. 82, No. 51 / Friday, March 17, 2017 / Rules and Regulations
Boeing Model 787–10 airplane was
published in the Federal Register on
September 20, 2016 (81 FR 64360). One
substantive comment was received.
By letter no. B–H020–REG–16–TLM–
68 dated November 1, 2016, Boeing
stated that they ‘‘. . . recommend that
development of future requirements for
the application of [active modalsuppression system for flutter
compliance] technology be the subject
of an Aviation Rulemaking Advisory
Committee (ARAC).’’ Boeing adds that
‘‘. . . standard requirements should be
developed which reflect this state-ofthe-art system and apply to all airplane
manufacturers. The development of
these requirements would benefit from
the collaborative effort of an ARAC.’’
The FAA agrees with Boeing and
currently has plans to task ARAC to
develop recommendations on this
subject.
mstockstill on DSK3G9T082PROD with RULES
Applicability
As discussed above, these special
conditions are applicable to the Boeing
Model 787–10 airplane. Should Boeing
apply at a later date for a change to the
type certificate to include another
VerDate Sep<11>2014
19:31 Mar 16, 2017
Jkt 241001
model incorporating the same novel or
unusual design feature, these special
conditions would apply to that model as
well.
Conclusion
This action affects only a certain
novel or unusual design feature on one
model series of airplane. 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 Special Conditions
Accordingly, pursuant to the
authority delegated to me by the
Administrator, the following special
conditions are issued as part of the type
certification basis for Boeing Model
787–10 airplanes.
The following special conditions are
proposed to address the aeroelastic
stability of the 787–10 airplane with the
PO 00000
Frm 00006
Fmt 4700
Sfmt 4725
F0VMS system as an integral part of the
PFCS Normal mode:
Analytical Flutter-Clearance
Requirements
1. The airplane in the PFCS Normal
mode (which includes F0VMS) must
meet the nominal (no failures) flutter
and aeroelastic stability requirements of
§ 25.629(b)(1), and the damping-margin
criteria of AC 25.629–1B, Section
7.1.3.3. Figure 1, below, illustrates the
Damping versus Airspeed plot.
a. The aeroservoelastic analysis must
take into account the effect of the
following items:
i. Significant structural and
aerodynamic nonlinearities.
ii. Significant F0VMS nonlinearities,
including control-surface rate and
displacement saturation, and
blowdown.
iii. The range of design maneuver load
factors.
iv. Control surface freeplay.
v. Any other items that may affect the
performance of the F0VMS system in
maintaining adequate modal damping
margins.
E:\FR\FM\17MRR1.SGM
17MRR1
ER17MR17.000
14116
Federal Register / Vol. 82, No. 51 / Friday, March 17, 2017 / Rules and Regulations
14117
KEAS) to zero damping margin to flutter
at 1.15 VD/1.15 MD, limited to Mach 1.0.
That is, the 3Hz mode should not cross
the g = 0.015 line below VD, or the g =
0.03 line below 1.15 VD, assuming the
use of analysis Method 1 of AC 25.629–
1B, Section 7.1.3.3. Figure 2, below,
illustrates the Damping versus Airspeed
plot.
3. The airplane in the PFCS Normal
mode (which includes F0VMS) must
meet the fail-safe flutter and aeroelastic
stability requirements of § 25.629(b)(2),
and the damping-margin criteria of AC
25.629–1B, Section 7.1.3.5.
4. The airplane in the PFCS
Secondary and Direct modes must meet
the fail-safe flutter and aeroelasticstability requirements of § 25.629(b)(2),
and the damping-margin criteria of AC
25.629–1B, Section 7.1.3.5.
DEPARTMENT OF TRANSPORTATION
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: This action is effective on
Embraer on March 17, 2017. We must
receive your comments by May 1, 2017.
ADDRESSES: Send comments identified
by docket number FAA–2016–9403
using any of the following methods:
• Federal eRegulations Portal: Go to
https://www.regulations.gov/ and follow
the online instructions for sending your
comments electronically.
• Mail: Send comments to Docket
Operations, M–30, U.S. Department of
Transportation (DOT), 1200 New Jersey
Avenue SE., Room W12–140, West
Building Ground Floor, Washington, DC
20590–0001.
• Hand Delivery or Courier: Take
comments to Docket Operations in
Room W12–140 of the West Building
Issued in Renton, Washington, on February
10, 2017.
Michael Kaszycki,
Assistant Manager, Transport Airplane
Directorate, Aircraft Certification Service.
mstockstill on DSK3G9T082PROD with RULES
[FR Doc. 2017–05326 Filed 3–16–17; 8:45 am]
BILLING CODE 4910–13–P
VerDate Sep<11>2014
19:31 Mar 16, 2017
Jkt 241001
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA–2016–9403; Special
Conditions No. 25–643–SC] Special
Conditions: Embraer, S.A., Model ERJ 190–
300 Airplane; Dive-Speed
Definition with High-Speed-Protection
System
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions; request
for comments.
AGENCY:
These special conditions are
issued for the Embraer, S.A., (Embraer)
Model ERJ 190–300 airplane. This
airplane will have a novel or unusual
design feature when compared to the
state of technology envisioned in the
airworthiness standards for transportcategory airplanes. This design feature
is a high-speed-protection system. The
applicable airworthiness regulations do
SUMMARY:
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17MRR1
ER17MR17.001
2. The airplane in the PFCS Normal
mode, but with the F0VMS system
inoperative, must exhibit a damping
margin to flutter of 0.015g within the
VD/MD envelope, linearly decreasing (in
Agencies
[Federal Register Volume 82, Number 51 (Friday, March 17, 2017)]
[Rules and Regulations]
[Pages 14115-14117]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-05326]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA-2016-6137; Special Conditions No. 25-644-SC]
Special Conditions: The Boeing Company Model 787-10 Airplane;
Aeroelastic Stability Requirements, Flaps-Up Vertical Modal-Suppression
System
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions.
-----------------------------------------------------------------------
SUMMARY: These special conditions are issued for the Boeing Company
(Boeing) Model 787-10 airplane. This airplane will have a novel or
unusual design feature when compared to the state of technology
envisioned in the airworthiness standards for transport-category
airplanes. This design feature is a flaps-up vertical modal-suppression
system, which is in lieu of traditional methods of improving airplane
flutter characteristics. The applicable airworthiness regulations do
not contain adequate or appropriate safety standards for this design
feature. These special conditions contain the additional safety
standards that the Administrator considers necessary to establish a
level of safety equivalent to that established by the existing
airworthiness standards.
DATES: Effective April 17, 2017.
FOR FURTHER INFORMATION CONTACT: Wael Nour, FAA, Airframe and Cabin
Safety Branch, ANM-115, Transport Airplane Directorate, Aircraft
Certification Service, 1601 Lind Avenue SW., Renton, Washington 98057-
3356; telephone 425-227-2143; facsimile 425-227-1320.
SUPPLEMENTARY INFORMATION:
Background
On July 30, 2013, Boeing applied for an amendment to Type
Certificate No. T00021SE to include the new Model 787-10 airplane. This
twin-engine, transport-category airplane is a stretched-fuselage
derivative of the 787-9, with maximum seating capacity of 440
passengers. The 787-10 has a maximum takeoff weight of 560,000 lbs.
Type Certification Basis
Under the provisions of Title 14, Code of Federal Regulations (14
CFR) 21.101, Boeing must show that the Model 787-10 airplane meets the
applicable provisions of the regulations listed in Type Certificate No.
T00021SE or the applicable regulations in effect on the date of
application for the change, except for earlier amendments as agreed
upon by the FAA.
In addition, the certification basis includes other regulations,
special conditions, and exemptions that are not relevant to these
proposed special conditions. Type Certificate No. T00021SE will be
updated to include a complete description of the certification basis
for this airplane model.
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 Model 787-10 airplane 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 feature, or should any other model already included on
the same type certificate be modified to incorporate the same novel or
unusual design feature, these special conditions would also apply to
the other model under Sec. 21.101.
In addition to the applicable airworthiness regulations and special
conditions, the Model 787-10 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.
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. 21.101.
Novel or Unusual Design Features
The Model 787-10 airplane will incorporate the following novel or
unusual design feature:
A flaps-up vertical modal suppression system.
Discussion
The Boeing Model 787-10 will add a new flaps-up vertical modal-
suppression (F0VMS) system to the Normal mode of the primary flight-
control system (PFCS). The F0VMS system is needed to satisfy the
flutter-damping margin requirements of Sec. 25.629 and the means-of-
compliance provisions in Advisory Circular (AC) 25.629-1B. This system
will be used in lieu of typical methods of improving the flutter
characteristics of an airplane, such as increasing the torsional
stiffness of the wing or adding wingtip ballast weights.
The F0VMS system is an active modal-suppression system that will
provide additional damping to an already stable, but low-damped, 3Hz
symmetric wing, nacelle, and body aeroelastic mode of the airplane.
This feedback-control system will maintain adequate damping margins to
flutter. The F0VMS system accomplishes this by oscillating the
elevators, and, when needed, the flaperons.
Because Boeing's flutter analysis shows that the 3Hz mode is stable
and does not flutter, the F0VMS system is not an active flutter-
suppression system, but, rather, a damping-augmentation system. At this
time, the FAA is not prepared to accept an active flutter-suppression
system that suppresses a divergent flutter mode in the operational or
design envelope of the airplane.
This will be the first time an active modal-suppression system will
be used for Sec. 25.629 compliance. The use of this new active modal-
suppression system for flutter compliance is novel or unusual when
compared to the technology envisioned in the current airworthiness
standards. Consequently, special conditions are required in
consideration of the effects of this new system on the aeroelastic
stability of the airplane, both in the normal and failed state, to
maintain the level of safety intended by Sec. 25.629.
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.
Discussion of Comments
Notice of Proposed Special Conditions No. 25-16-05-SC for the
[[Page 14116]]
Boeing Model 787-10 airplane was published in the Federal Register on
September 20, 2016 (81 FR 64360). One substantive comment was received.
By letter no. B-H020-REG-16-TLM-68 dated November 1, 2016, Boeing
stated that they ``. . . recommend that development of future
requirements for the application of [active modal-suppression system
for flutter compliance] technology be the subject of an Aviation
Rulemaking Advisory Committee (ARAC).'' Boeing adds that ``. . .
standard requirements should be developed which reflect this state-of-
the-art system and apply to all airplane manufacturers. The development
of these requirements would benefit from the collaborative effort of an
ARAC.''
The FAA agrees with Boeing and currently has plans to task ARAC to
develop recommendations on this subject.
Applicability
As discussed above, these special conditions are applicable to the
Boeing Model 787-10 airplane. Should Boeing apply at a later date for a
change to the type certificate to include another model incorporating
the same novel or unusual design feature, these special conditions
would apply to that model as well.
Conclusion
This action affects only a certain novel or unusual design feature
on one model series of airplane. 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 Special Conditions
Accordingly, pursuant to the authority delegated to me by the
Administrator, the following special conditions are issued as part of
the type certification basis for Boeing Model 787-10 airplanes.
The following special conditions are proposed to address the
aeroelastic stability of the 787-10 airplane with the F0VMS system as
an integral part of the PFCS Normal mode:
Analytical Flutter-Clearance Requirements
1. The airplane in the PFCS Normal mode (which includes F0VMS) must
meet the nominal (no failures) flutter and aeroelastic stability
requirements of Sec. 25.629(b)(1), and the damping-margin criteria of
AC 25.629-1B, Section 7.1.3.3. Figure 1, below, illustrates the Damping
versus Airspeed plot.
a. The aeroservoelastic analysis must take into account the effect
of the following items:
i. Significant structural and aerodynamic nonlinearities.
ii. Significant F0VMS nonlinearities, including control-surface
rate and displacement saturation, and blowdown.
iii. The range of design maneuver load factors.
iv. Control surface freeplay.
v. Any other items that may affect the performance of the F0VMS
system in maintaining adequate modal damping margins.
[GRAPHIC] [TIFF OMITTED] TR17MR17.000
[[Page 14117]]
2. The airplane in the PFCS Normal mode, but with the F0VMS system
inoperative, must exhibit a damping margin to flutter of 0.015g within
the VD/MD envelope, linearly decreasing (in KEAS)
to zero damping margin to flutter at 1.15 VD/1.15
MD, limited to Mach 1.0. That is, the 3Hz mode should not
cross the g = 0.015 line below VD, or the g = 0.03 line
below 1.15 VD, assuming the use of analysis Method 1 of AC
25.629-1B, Section 7.1.3.3. Figure 2, below, illustrates the Damping
versus Airspeed plot.
[GRAPHIC] [TIFF OMITTED] TR17MR17.001
3. The airplane in the PFCS Normal mode (which includes F0VMS) must
meet the fail-safe flutter and aeroelastic stability requirements of
Sec. 25.629(b)(2), and the damping-margin criteria of AC 25.629-1B,
Section 7.1.3.5.
4. The airplane in the PFCS Secondary and Direct modes must meet
the fail-safe flutter and aeroelastic-stability requirements of Sec.
25.629(b)(2), and the damping-margin criteria of AC 25.629-1B, Section
7.1.3.5.
Issued in Renton, Washington, on February 10, 2017.
Michael Kaszycki,
Assistant Manager, Transport Airplane Directorate, Aircraft
Certification Service.
[FR Doc. 2017-05326 Filed 3-16-17; 8:45 am]
BILLING CODE 4910-13-P