Special Conditions: Boeing Model 787 Series Airplanes; Seats With Inertia Locking Devices, 26739-26741 [2019-12121]
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26739
Rules and Regulations
Federal Register
Vol. 84, No. 111
Monday, June 10, 2019
This section of the FEDERAL REGISTER
contains regulatory documents having general
applicability and legal effect, most of which
are keyed to and codified in the Code of
Federal Regulations, which is published under
50 titles pursuant to 44 U.S.C. 1510.
The Code of Federal Regulations is sold by
the Superintendent of Documents.
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA–2019–0236; Special
Conditions No. 25–745–SC]
Special Conditions: Boeing Model 787
Series Airplanes; Seats With Inertia
Locking Devices
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions.
AGENCY:
These special conditions are
issued for the Boeing Model 787 series
airplane. These airplanes 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 seats
with inertia locking devices. 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 June 10, 2019.
FOR FURTHER INFORMATION CONTACT:
Shannon Lennon, Cabin and Airframe
Safety Section, AIR–675, Transport
Standards Branch, Policy and
Innovation Division, Aircraft
Certification Service, Federal Aviation
Administration, 2200 South 216th
Street, Des Moines, Washington 98198;
telephone and fax 206–231–3209; email
shannon.lennon@faa.gov.
SUPPLEMENTARY INFORMATION:
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SUMMARY:
Background
On February 14, 2019, Boeing applied
for a change to Type Certificate No.
T00021SE for seats with inertia locking
devices in Model 787 series airplanes.
The Model 787 series airplane is a twin-
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engine transport-category airplane with
a maximum takeoff weight of 560,000
pounds and seating for 440 passengers.
Type Certification Basis
Under the provisions of title 14, Code
of Federal Regulations (14 CFR) 21.101,
Boeing must show that the Model 787
series airplanes, as changed, continue to
meet 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.
If the Administrator finds that the
applicable airworthiness regulations
(i.e., 14 CFR part 25) do not contain
adequate or appropriate safety standards
for Boeing Model 787 series airplanes
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, Boeing Model 787 series
airplanes must comply with the fuelvent and exhaust-emission requirements
of 14 CFR part 34, and the noisecertification 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.
Novel or Unusual Design Features
Boeing Model 787 series airplanes
will incorporate the following novel or
unusual design features:
Seats with inertia locking devices
(ILD).
Discussion
Boeing will install, in Model 787
series airplanes, Thompson Aero
Seating Ltd. passenger seats that can be
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translated in the fore and aft direction
by an electrically powered motor
(actuator) that is attached to the seat
primary structure. Under typical
service-loading conditions, the motor
internal brake is able to translate the
seat and hold the seat in the translated
position. However, under the inertial
loads of emergency-landing loading
conditions specified in 14 CFR 25.562,
the motor internal brake may not be able
to maintain the seat in the required
position. The ILD is an ‘‘active’’ device
intended to control seat movement (i.e.,
a system that mechanically deploys
during an impact event) to lock the
gears of the motor assembly in place.
The ILD mechanism is activated by the
higher inertial load factors that could
occur during an emergency landing
event. Each seat place incorporates two
ILDs; one on either side of the seat pan.
Only one ILD is required to hold an
occupied seat in position during worstcase dynamic loading specified in
§ 25.562.
The ILD will self-activate only in the
event of a predetermined airplane
loading condition such as that occurring
during crash or emergency landing, and
will prevent excessive seat forward
translation. A minimum level of
protection must be provided if the seatlocking device does not deploy.
The normal means of satisfying the
structural and occupant protection
requirements of § 25.562 result in a nonquantified, but predictable, progressive
structural deformation or reduction of
injury severity for impact conditions
less than the maximum specified by the
rule. A seat using ILD technology,
however, may involve a step change in
protection for impacts below and above
that at which the ILD activates and
deploys to retain the seat pan in place.
This could result in structural
deformation or occupant injury output
being higher at an intermediate impact
condition than that resulting from the
maximum impact condition. It is
acceptable for such step-change
characteristics to exist, provided the
resulting output does not exceed the
maximum allowable criteria at any
condition at which the ILD does or does
not deploy, up to the maximum severity
pulse specified by the requirements.
The ideal triangular maximum
severity pulse is defined in Advisory
Circular (AC) 25.562–1B. For the
evaluation and testing of less-severe
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pulses for purposes of assessing the
effectiveness of the ILD deployment
setting, a similar triangular pulse should
be used with acceleration, rise time, and
velocity change scaled accordingly. The
magnitude of the required pulse should
not deviate below the ideal pulse by
more than 0.5g until 1.33 t1 is reached,
where t1 represents the time interval
between 0 and t1 on the referenced
pulse shape as shown in AC 25.562–1B.
This is an acceptable method of
compliance to the test requirements of
the special conditions.
Conditions 1 through 5 address
ensuring that the ILD activates when
intended in order to provide the
necessary protection of occupants. This
includes protection of a range of
occupants under various accident
conditions. Conditions 6 through 10
address maintenance and reliability of
the ILD, including any outside
influences on the mechanism, to ensure
it functions as intended.
The 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
The FAA issued Notice of Proposed
Special Conditions No. 25–19–03–SC,
for the Boeing Model 787 series
airplane, which was published in the
Federal Register on April 29, 2019 (84
FR 17977). The FAA received responses
from two commenters.
One commenter writes:
Seats are dynamically tested in
upright positions to show compliance
with 14 CFR part 25.562. In this specific
installation, there is a mechanical or
electrical actuation of the movement of
the seat, and the following points of
concern may raise:
(1) If the motor loses electrical power
before a crash during an actuation, can
it lock the seat in a position other than
that considered for [taxi, takeoff, and
landing] TTL?
(2) There should be included a
Special Condition to address possible
interference of lightning and highintensity radiated fields on the motor or
its commands;
(3) Design features should be
demanded to avoid the seat to be locked
in an intermediate position (for
example, because of fail in link between
the seat structure and the actuator).
The FAA clarifies, regarding the
commenter’s concerns about seatactuator motor disability and impact on
the seat position due to loss of power or
other conditions, the seat design
includes a manual-override feature to
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restore the seat in the required position.
However, while the actuator motor is
part of the seat-actuation system, this
feature is not the subject of the proposed
special conditions. Rather, the special
conditions address the ILDs, which are
a different component of the seatactuation system and are intended to
ensure that the seat position is
maintained in the event that the
structural capability of the actuator
motor brake is exceeded during
emergency-landing conditions. The ILDs
are a mechanical interlock feature and
are not affected by loss of power or
external electrical forces.
Another commenter asks if such extra
safety precautions as ILDs may
potentially be implemented in other
airplane models, adding that seats with
inertia locking devices likely enhance
air-travel safety.
The FAA agrees that ILDs enhance
airplane safety. It is possible that ILDs
potentially will be incorporated into
seat designs intended for installation on
other airplane models. Incorporation of
such a feature is contingent on the
airplane manufacturer’s determination
to install seats that include ILDs as part
of a seat-actuation system.
The comments do not change the
special conditions, and the special
conditions are adopted as proposed.
Applicability
As discussed above, these special
conditions are applicable to Boeing
Model 787 series airplanes. 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 one novel or
unusual design feature on one model
series of airplanes. It is not a rule of
general applicability.
List of Subjects in 14 CFR Part 25
Aircraft, Aviation safety, Reporting
and recordkeeping requirements.
Authority Citation
The authority citation for these
special conditions is as follows:
Authority: 49 U.S.C. 106(f), 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
series airplanes.
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Fmt 4700
Sfmt 4700
In addition to the requirements of
§ 25.562, passenger seats incorporating
an inertia locking device (ILD) must
meet the following:
1. Level of Protection Provided by
ILD—It must be demonstrated by test
that the seats and attachments, when
subject to the emergency-landing
dynamic conditions specified in
§ 25.562, and with one ILD not
deployed, do not experience structural
failure that could result in:
a. Separation of the seat from the
airplane floor.
b. Separation of any part of the seat
that could form a hazard to the seat
occupant or any other airplane
occupant.
c. Failure of the occupant restraint or
any other condition that could result in
the occupant separating from the seat.
2. Protection Provided Below and
Above the ILD Actuation Condition—If
step-change effects on occupant
protection exist for impacts below and
above that at which the ILD deploys,
tests must be performed to demonstrate
that the occupant is shown to be
protected at any condition at which the
ILD does or does not deploy, up to the
maximum severity pulse specified by
§ 25.562. Test conditions must take into
account any necessary tolerances for
deployment.
3. Protection Over a Range of Crash
Pulse Vectors—The ILD must be shown
to function as intended for all test
vectors specified in § 25.562.
4. Protection During Secondary
Impacts—The ILD activation setting
must be demonstrated to maximize the
probability of the protection being
available when needed, considering a
secondary impact that is above the
severity at which the device is intended
to deploy up to the impact loading
required by § 25.562.
5. Protection of Occupants other than
50th Percentile—Protection of
occupants for a range of stature from a
two-year-old child to a ninety-five
percentile male must be shown.
6. Inadvertent Operation—It must be
shown that any inadvertent operation of
the ILD does not affect the performance
of the device during a subsequent
emergency landing.
7. Installation Protection—It must be
shown that the ILD installation is
protected from contamination and
interference from foreign objects.
8. Reliability—The performance of the
ILD must not be altered by the effects of
wear, manufacturing tolerances, aging or
drying of lubricants, and corrosion.
9. Maintenance and Functional
Checks—The design, installation, and
operation of the ILD must be such that
it is possible to functionally check the
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Federal Register / Vol. 84, No. 111 / Monday, June 10, 2019 / Rules and Regulations
device in place. Additionally, a
functional check method and a
maintenance check interval must be
included in the seat installer’s
instructions for continued airworthiness
(ICA) document.
10. Release Function—If a means
exists to release an inadvertently
activated ILD, the release means must
not introduce additional hidden failures
that would prevent the ILD from
functioning properly.
Issued in Des Moines, Washington, on June
5, 2019.
Paul Siegmund,
Acting Manager, Transport Standards
Branch, Policy and Innovation Division,
Aircraft Certification Service.
[FR Doc. 2019–12121 Filed 6–7–19; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA–2019–0424; Special
Conditions No. 25–748–SC]
Special Conditions: Mitsubishi Aircraft
Corporation, Model MRJ–200 Airplane;
Operation Without Normal Electrical
Power
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions; request
for comments.
AGENCY:
These special conditions are
issued for the Mitsubishi Aircraft
Corporation (MITAC), Model MRJ–200
airplanes. These airplanes will have a
novel or unusual design feature when
compared to the state of technology
envisioned in the airworthiness
standards for transport category
airplanes. These design features are
electrical and electronic systems that
perform critical functions, the loss of
which could be catastrophic to the
airplane. The applicable airworthiness
regulations do not contain adequate or
appropriate safety standards for this
design features. 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
MITAC on June 10, 2019. Send
comments on or before July 25, 2019.
ADDRESSES: Send comments identified
by Docket No. FAA–2019–0424 using
any of the following methods:
• Federal eRegulations Portal: Go to
https://www.regulations.gov/ and follow
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SUMMARY:
VerDate Sep<11>2014
15:41 Jun 07, 2019
Jkt 247001
26741
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
Ground Floor at 1200 New Jersey
Avenue SE, Washington, DC, between 9
a.m. and 5 p.m., Monday through
Friday, except Federal holidays.
• Fax: Fax comments to Docket
Operations at 202–493–2251.
Privacy: The FAA will post all
comments it receives, without change,
to https://www.regulations.gov/,
including any personal information the
commenter provides. Using the search
function of the docket website, anyone
can find and read the electronic form of
all comments received into any FAA
docket, including the name of the
individual sending the comment (or
signing the comment for an association,
business, labor union, etc.). DOT’s
complete Privacy Act Statement can be
found in the Federal Register published
on April 11, 2000 (65 FR 19477–19478).
Docket: Background documents or
comments received may be read at
https://www.regulations.gov/ at any time.
Follow the online instructions for
accessing the docket or go to Docket
Operations in Room W12–140 of the
West Building Ground Floor at 1200
New Jersey Avenue SE, Washington,
DC, between 9 a.m. and 5 p.m., Monday
through Friday, except Federal holidays.
FOR FURTHER INFORMATION CONTACT:
Dean Thompson, Airplane and Flight
Crew Interface Section, AIR–671,
Transport Standards Branch, Policy and
Innovation Division, Aircraft
Certification Service, Federal Aviation
Administration, 2200 South 216th
Street, Des Moines, Washington 98198;
telephone and fax 206–231–3165; email
Dean.R.Thompson@faa.gov.
SUPPLEMENTARY INFORMATION: The
substance of these special conditions
has been published in the Federal
Register for public comment in several
prior instances with no substantive
comments received. Therefore, the FAA
has determined that prior public notice
and comment are unnecessary, and
finds that, for the same reason, good
cause exists for adopting these special
conditions upon publication in the
Federal Register.
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 will consider all comments we
receive by the closing date for
comments. We may change these special
conditions based on the comments we
receive.
Comments Invited
The MITAC Model MRJ–200 airplanes
will incorporate the following novel or
unusual design features:
We invite interested people to take
part in this rulemaking by sending
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Background
On March 3, 2015, MITAC applied for
a type certificate for their new Model
MRJ–200 airplanes. The MITAC Model
MRJ–200 airplane is a low-wing,
conventional-tail design with two wingmounted turbofan engines. The airplane
has seating for 92 passengers and a
maximum takeoff weight of 95,000 lbs.
Type Certification Basis
Under the provisions of title 14, Code
of Federal Regulations (14 CFR) 21.17,
MITAC must show that the Model MRJ–
200 airplanes meet the applicable
provisions of part 25, as amended by
amendments 25–1 through 25–141; and
part 26 continued airworthiness
certification requirements, as amended
by Amendments 26–1 through 26–6.
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 MITAC MRJ–200 airplanes
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, these special conditions
would also apply to the other model
under § 21.101.
In addition to the applicable
airworthiness regulations and special
conditions, the MITAC MRJ–200
airplanes 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
§ 21.17(a)(2).
Novel or Unusual Design Features
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Agencies
[Federal Register Volume 84, Number 111 (Monday, June 10, 2019)]
[Rules and Regulations]
[Pages 26739-26741]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-12121]
========================================================================
Rules and Regulations
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains regulatory documents
having general applicability and legal effect, most of which are keyed
to and codified in the Code of Federal Regulations, which is published
under 50 titles pursuant to 44 U.S.C. 1510.
The Code of Federal Regulations is sold by the Superintendent of Documents.
========================================================================
Federal Register / Vol. 84, No. 111 / Monday, June 10, 2019 / Rules
and Regulations
[[Page 26739]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA-2019-0236; Special Conditions No. 25-745-SC]
Special Conditions: Boeing Model 787 Series Airplanes; Seats With
Inertia Locking Devices
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions.
-----------------------------------------------------------------------
SUMMARY: These special conditions are issued for the Boeing Model 787
series airplane. These airplanes 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 seats with inertia locking devices. 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 June 10, 2019.
FOR FURTHER INFORMATION CONTACT: Shannon Lennon, Cabin and Airframe
Safety Section, AIR-675, Transport Standards Branch, Policy and
Innovation Division, Aircraft Certification Service, Federal Aviation
Administration, 2200 South 216th Street, Des Moines, Washington 98198;
telephone and fax 206-231-3209; email [email protected].
SUPPLEMENTARY INFORMATION:
Background
On February 14, 2019, Boeing applied for a change to Type
Certificate No. T00021SE for seats with inertia locking devices in
Model 787 series airplanes. The Model 787 series airplane is a twin-
engine transport-category airplane with a maximum takeoff weight of
560,000 pounds and seating for 440 passengers.
Type Certification Basis
Under the provisions of title 14, Code of Federal Regulations (14
CFR) 21.101, Boeing must show that the Model 787 series airplanes, as
changed, continue to meet 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.
If the Administrator finds that the applicable airworthiness
regulations (i.e., 14 CFR part 25) do not contain adequate or
appropriate safety standards for Boeing Model 787 series airplanes
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, Boeing Model 787 series airplanes 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
Boeing Model 787 series airplanes will incorporate the following
novel or unusual design features:
Seats with inertia locking devices (ILD).
Discussion
Boeing will install, in Model 787 series airplanes, Thompson Aero
Seating Ltd. passenger seats that can be translated in the fore and aft
direction by an electrically powered motor (actuator) that is attached
to the seat primary structure. Under typical service-loading
conditions, the motor internal brake is able to translate the seat and
hold the seat in the translated position. However, under the inertial
loads of emergency-landing loading conditions specified in 14 CFR
25.562, the motor internal brake may not be able to maintain the seat
in the required position. The ILD is an ``active'' device intended to
control seat movement (i.e., a system that mechanically deploys during
an impact event) to lock the gears of the motor assembly in place. The
ILD mechanism is activated by the higher inertial load factors that
could occur during an emergency landing event. Each seat place
incorporates two ILDs; one on either side of the seat pan. Only one ILD
is required to hold an occupied seat in position during worst-case
dynamic loading specified in Sec. 25.562.
The ILD will self-activate only in the event of a predetermined
airplane loading condition such as that occurring during crash or
emergency landing, and will prevent excessive seat forward translation.
A minimum level of protection must be provided if the seat-locking
device does not deploy.
The normal means of satisfying the structural and occupant
protection requirements of Sec. 25.562 result in a non-quantified, but
predictable, progressive structural deformation or reduction of injury
severity for impact conditions less than the maximum specified by the
rule. A seat using ILD technology, however, may involve a step change
in protection for impacts below and above that at which the ILD
activates and deploys to retain the seat pan in place. This could
result in structural deformation or occupant injury output being higher
at an intermediate impact condition than that resulting from the
maximum impact condition. It is acceptable for such step-change
characteristics to exist, provided the resulting output does not exceed
the maximum allowable criteria at any condition at which the ILD does
or does not deploy, up to the maximum severity pulse specified by the
requirements.
The ideal triangular maximum severity pulse is defined in Advisory
Circular (AC) 25.562-1B. For the evaluation and testing of less-severe
[[Page 26740]]
pulses for purposes of assessing the effectiveness of the ILD
deployment setting, a similar triangular pulse should be used with
acceleration, rise time, and velocity change scaled accordingly. The
magnitude of the required pulse should not deviate below the ideal
pulse by more than 0.5g until 1.33 t1 is reached, where
t1 represents the time interval between 0 and t1
on the referenced pulse shape as shown in AC 25.562-1B. This is an
acceptable method of compliance to the test requirements of the special
conditions.
Conditions 1 through 5 address ensuring that the ILD activates when
intended in order to provide the necessary protection of occupants.
This includes protection of a range of occupants under various accident
conditions. Conditions 6 through 10 address maintenance and reliability
of the ILD, including any outside influences on the mechanism, to
ensure it functions as intended.
The 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
The FAA issued Notice of Proposed Special Conditions No. 25-19-03-
SC, for the Boeing Model 787 series airplane, which was published in
the Federal Register on April 29, 2019 (84 FR 17977). The FAA received
responses from two commenters.
One commenter writes:
Seats are dynamically tested in upright positions to show
compliance with 14 CFR part 25.562. In this specific installation,
there is a mechanical or electrical actuation of the movement of the
seat, and the following points of concern may raise:
(1) If the motor loses electrical power before a crash during an
actuation, can it lock the seat in a position other than that
considered for [taxi, takeoff, and landing] TTL?
(2) There should be included a Special Condition to address
possible interference of lightning and high-intensity radiated fields
on the motor or its commands;
(3) Design features should be demanded to avoid the seat to be
locked in an intermediate position (for example, because of fail in
link between the seat structure and the actuator).
The FAA clarifies, regarding the commenter's concerns about seat-
actuator motor disability and impact on the seat position due to loss
of power or other conditions, the seat design includes a manual-
override feature to restore the seat in the required position. However,
while the actuator motor is part of the seat-actuation system, this
feature is not the subject of the proposed special conditions. Rather,
the special conditions address the ILDs, which are a different
component of the seat-actuation system and are intended to ensure that
the seat position is maintained in the event that the structural
capability of the actuator motor brake is exceeded during emergency-
landing conditions. The ILDs are a mechanical interlock feature and are
not affected by loss of power or external electrical forces.
Another commenter asks if such extra safety precautions as ILDs may
potentially be implemented in other airplane models, adding that seats
with inertia locking devices likely enhance air-travel safety.
The FAA agrees that ILDs enhance airplane safety. It is possible
that ILDs potentially will be incorporated into seat designs intended
for installation on other airplane models. Incorporation of such a
feature is contingent on the airplane manufacturer's determination to
install seats that include ILDs as part of a seat-actuation system.
The comments do not change the special conditions, and the special
conditions are adopted as proposed.
Applicability
As discussed above, these special conditions are applicable to
Boeing Model 787 series airplanes. 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 one novel or unusual design feature on one
model series of airplanes. It is not a rule of general applicability.
List of Subjects in 14 CFR Part 25
Aircraft, Aviation safety, Reporting and recordkeeping
requirements.
Authority Citation
The authority citation for these special conditions is as follows:
Authority: 49 U.S.C. 106(f), 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 series airplanes.
In addition to the requirements of Sec. 25.562, passenger seats
incorporating an inertia locking device (ILD) must meet the following:
1. Level of Protection Provided by ILD--It must be demonstrated by
test that the seats and attachments, when subject to the emergency-
landing dynamic conditions specified in Sec. 25.562, and with one ILD
not deployed, do not experience structural failure that could result
in:
a. Separation of the seat from the airplane floor.
b. Separation of any part of the seat that could form a hazard to
the seat occupant or any other airplane occupant.
c. Failure of the occupant restraint or any other condition that
could result in the occupant separating from the seat.
2. Protection Provided Below and Above the ILD Actuation
Condition--If step-change effects on occupant protection exist for
impacts below and above that at which the ILD deploys, tests must be
performed to demonstrate that the occupant is shown to be protected at
any condition at which the ILD does or does not deploy, up to the
maximum severity pulse specified by Sec. 25.562. Test conditions must
take into account any necessary tolerances for deployment.
3. Protection Over a Range of Crash Pulse Vectors--The ILD must be
shown to function as intended for all test vectors specified in Sec.
25.562.
4. Protection During Secondary Impacts--The ILD activation setting
must be demonstrated to maximize the probability of the protection
being available when needed, considering a secondary impact that is
above the severity at which the device is intended to deploy up to the
impact loading required by Sec. 25.562.
5. Protection of Occupants other than 50th Percentile--Protection
of occupants for a range of stature from a two-year-old child to a
ninety-five percentile male must be shown.
6. Inadvertent Operation--It must be shown that any inadvertent
operation of the ILD does not affect the performance of the device
during a subsequent emergency landing.
7. Installation Protection--It must be shown that the ILD
installation is protected from contamination and interference from
foreign objects.
8. Reliability--The performance of the ILD must not be altered by
the effects of wear, manufacturing tolerances, aging or drying of
lubricants, and corrosion.
9. Maintenance and Functional Checks--The design, installation, and
operation of the ILD must be such that it is possible to functionally
check the
[[Page 26741]]
device in place. Additionally, a functional check method and a
maintenance check interval must be included in the seat installer's
instructions for continued airworthiness (ICA) document.
10. Release Function--If a means exists to release an inadvertently
activated ILD, the release means must not introduce additional hidden
failures that would prevent the ILD from functioning properly.
Issued in Des Moines, Washington, on June 5, 2019.
Paul Siegmund,
Acting Manager, Transport Standards Branch, Policy and Innovation
Division, Aircraft Certification Service.
[FR Doc. 2019-12121 Filed 6-7-19; 8:45 am]
BILLING CODE 4910-13-P