Special Conditions: B/E Aerospace, Bombardier Model CL-600-2B16 (604 Variant) Airplane; Seats With Pretensioner Restraint Systems, 55198-55200 [2020-18309]
Download as PDF
55198
Proposed Rules
Federal Register
Vol. 85, No. 173
Friday, September 4, 2020
This section of the FEDERAL REGISTER
contains notices to the public of the proposed
issuance of rules and regulations. The
purpose of these notices is to give interested
persons an opportunity to participate in the
rule making prior to the adoption of the final
rules.
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA–2020–0404; Notice No. 25–
20–04–SC]
Special Conditions: B/E Aerospace,
Bombardier Model CL–600–2B16 (604
Variant) Airplane; Seats With
Pretensioner Restraint Systems
Federal Aviation
Administration (FAA), DOT.
ACTION: Notice of proposed special
conditions.
AGENCY:
This action proposes special
conditions for the Bombardier Inc.
(Bombardier) Model CL–600–2B16 (604
variant) airplane. This airplane, as
modified by B/E Aerospace, 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 a 3-point shoulder harness
incorporating a pretensioner restraint
system. The applicable airworthiness
regulations do not contain adequate or
appropriate safety standards for this
design feature. 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: Send comments on or before
October 19, 2020.
ADDRESSES: Send comments identified
by Docket No. FAA–2020–0404 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.
jbell on DSKJLSW7X2PROD with PROPOSALS
SUMMARY:
VerDate Sep<11>2014
15:57 Sep 03, 2020
Jkt 250001
• 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:
Shannon Lennon, Airframe and Cabin
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:
Comments Invited
The FAA invites 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.
The FAA will consider all comments
received by the closing date for
comments. The FAA may change these
special conditions based on the
comments received.
PO 00000
Frm 00001
Fmt 4702
Sfmt 4702
Background
On June 7, 2019, B/E Aerospace
applied for a supplemental type
certificate for seats with 3-point harness
and pretensioner restraint systems in
Bombardier Model CL–600–2B16 (604
variant) airplanes. The 604 variant is a
derivative of the Bombardier Model CL–
600–2B16 airplane currently approved
under Type Certificate No. A21EA. This
airplane variant is a twin-engine,
transport category airplane with seating
for 22 passengers, including crew, and
a maximum take-off weight of 47,600
pounds.
Type Certification Basis
Under the provisions of title 14, Code
of Federal Regulations (14 CFR) 21.101,
B/E Aerospace must show that the
Bombardier Model CL–600–2B16 (604
variant) airplane, as changed, continues
to meet the applicable provisions of the
regulations listed in Type Certificate No.
A21EA 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
(e.g., 14 CFR part 25) do not contain
adequate or appropriate safety standards
for the Bombardier Model CL–600–2B16
(604 variant) 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 applicant apply
for a supplemental type certificate to
modify any other model included on the
same type certificate 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 Bombardier Model CL–
600–2B16 (604 variant) airplane must
comply with the fuel-vent and exhaustemission 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.
E:\FR\FM\04SEP1.SGM
04SEP1
Federal Register / Vol. 85, No. 173 / Friday, September 4, 2020 / Proposed Rules
Novel or Unusual Design Features
The Bombardier Model CL–600–2B16
(604 variant) airplane will incorporate
the following novel or unusual design
features: Seats with a 3-point shoulder
harness incorporating a pretensioner
restraint system to prevent head
injuries.
jbell on DSKJLSW7X2PROD with PROPOSALS
Discussion
B/E Aerospace has developed a
system in which a pretensioning
automotive retractor eliminates slack in
the 3-point shoulder harness, pulling
the occupant back into the seat prior to
impact. This has the effect of reducing
forward translation of the occupant
(reduced head arc), while reducing the
loads in the shoulder harness. B/E
Aerospace will install, in Bombardier
Model CL–600–2B16 (604 variant)
airplanes, seats that incorporate a 3point harness and pretensioner restraint
system to protect seat occupants from
head injuries.
Over the past 10 years, multiple
sensor-driven systems have been
installed in various airplanes to meet
improved crashworthiness regulations.
A sensor-driven system is defined as
any system that activates due to a signal
sent by an impact-triggered inertial
sensor. These types of systems include
a lap-belt airbag, a structure-mounted
airbag, and a 3-point harness and
pretensioner restraint system.
Shoulder harnesses have been widely
used on flight-attendant seats, flightdeck seats, in business jets, and in
general-aviation airplanes to reduce
occupant head injury in the unlikely
event of an emergency landing. Special
conditions, pertinent regulations, and
guidance have been published, relating
to other or existing restraint systems.
However, the use of a pretensioner
restraint system with a 3-point harness
on transport airplane seats is a novel
design.
Pretensioner technology involves a
step change in loading experienced by
the occupant for impacts below and
above that at which the device activates,
because the upper torso excursion
would be interrupted by activation of
the shoulder harness. This could result
in the head-injury criteria being higher
at an intermediate impact condition
than that resulting from the maximum
impact condition corresponding to the
test conditions specified in § 25.562.
The ideal triangular maximumseverity pulse is defined in Advisory
Circular 25.562–1B Dynamic Evaluation
of Seat Restraint Systems and Occupant
Protection on Transport Airplanes with
Change 1, dated January 10, 2006. For
evaluating and testing less-severe pulses
VerDate Sep<11>2014
15:57 Sep 03, 2020
Jkt 250001
to assess the effectiveness of the
pretensioner 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 these special
conditions.
Additionally, the pretensioner might
not provide protection, after actuation,
during secondary impacts. Therefore,
the case where a small impact is
followed by a large impact should be
addressed. If the minimum deceleration
severity at which the pretensioner is set
to activate is unnecessarily low, the
protection offered by the pretensioner
may be lost by the time a second larger
impact occurs.
The existing regulations do not
adequately address seats with
pretensioner restraint systems.
Therefore, the proposed configuration
requires special conditions.
Special conditions 1 through 5
address ensuring that the pretensioner
system activates when intended, to
provide the necessary protection of
occupants. This includes protection of a
range of occupants under various
accident conditions. Special conditions
6 through 11 address maintenance and
reliability of the pretensioner system,
including any outside influences on the
mechanism, to ensure it functions as
intended.
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.
Applicability
As discussed above, these special
conditions are applicable to the
Bombardier Model CL–600–2B16 (604
variant) airplanes as modified by B/E
Aerospace. Should B/E Aerospace apply
at a later date for a supplemental type
certificate to modify any other model
included on Type Certificate No. A21EA
to incorporate 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 of airplanes. It is not a rule of
general applicability and affects only
the applicant who applied to the FAA
PO 00000
Frm 00002
Fmt 4702
Sfmt 4702
55199
for approval of these features on the
airplane.
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, and 44704.
The Proposed Special Conditions
Accordingly, the Federal Aviation
Administration (FAA) proposes the
following special conditions as part of
the type certification basis for
Bombardier Model CL–600–2B16 (604
variant) airplanes as modified by B/E
Aerospace.
In addition to the requirements of
§§ 25.562, forward-facing passenger
seats incorporating pretensioner
restraint systems must meet the
following:
1. Head Injury Criteria—The Head
Injury Criteria value must not exceed
1,000 units at any condition at which
the pretensioner does or does not
deploy, up to the maximum severity
pulse that corresponds to the test
conditions specified in § 25.562. Tests
must be performed to demonstrate this,
taking into account any necessary
tolerances for deployment.
2. Protection during Secondary
Impacts—The pretensioner activation
setting must be demonstrated to
maximize the probability of the
protection being available when needed,
considering secondary impacts.
3. Protection of Occupants Other than
50th Percentile—Protection of
occupants for a range of stature from a
2-year-old child to a 95th percentile
male must be shown. For shoulder
harnesses that include pretensioners,
protection of occupants other than a
50th percentile male may be shown by
test or analysis. In addition, the
pretensioner must not introduce a
hazard to passengers due to the
following seating configurations:
a. The seat occupant is holding an
infant.
b. The seat occupant is a child in a
child restraint device.
c. The seat occupant is a pregnant
woman.
4. Occupants Adopting the Brace
Position—Occupants in the traditional
brace position when the pretensioner
activates must not experience adverse
effects from the pretensioner activation.
5. Inadvertent Pretensioner Actuation
a. The probability of inadvertent
pretensioner actuation must be shown
to be extremely remote (i.e., average
E:\FR\FM\04SEP1.SGM
04SEP1
55200
Federal Register / Vol. 85, No. 173 / Friday, September 4, 2020 / Proposed Rules
jbell on DSKJLSW7X2PROD with PROPOSALS
probability per flight hour of less than
10¥7).
b. The system must be shown not
susceptible to inadvertent pretensioner
actuation as a result of wear and tear, or
inertia loads resulting from in-flight or
ground maneuvers likely to be
experienced in service.
c. The seated occupant must not be
seriously injured as a result of
inadvertent pretensioner actuation.
d. Inadvertent pretensioner activation
must not cause a hazard to the airplane
nor cause serious injury to anyone who
may be positioned close to the retractor
or belt (e.g., seated in an adjacent seat
or standing adjacent to the seat).
6. Availability of the Pretensioner
Function Prior to Flight—The design
must provide means for a crewmember
to verify the availability of the
pretensioner function prior to each
flight, or the probability of failure of the
pretensioner function must be
demonstrated to be extremely remote
(i.e., average probability per flight hour
of less than 10¥7) between inspection
intervals.
7. Incorrect Seatbelt Orientation—The
system design must ensure that any
incorrect orientation (twisting) of the
seatbelt does not compromise the
pretensioner protection function.
8. Contamination Protection—The
pretensioner mechanisms and controls
must be protected from external
contamination associated with that
which could occur on or around
passenger seating.
9. Prevention of Hazards—The
pretensioner system must not induce a
hazard to passengers in case of fire, nor
create a fire hazard if activated.
10. Functionality after Loss of
Power—The system must function
properly after loss of normal airplane
electrical power, and after a transverse
separation in the fuselage at the most
critical location. A separation at the
location of the system does not have to
be considered.
11. High-intensity Radiated Fields
(HIRF) and Lightning Protection—For
airplanes that do not already
incorporate 14 CFR 25.1316 and 25.1317
into their certification basis, the
equipment must meet the applicable
requirements of §§ 25.1316 and 25.1317.
Electrostatic discharge must also be
considered in the design and testing of
the equipment.
Issued in Des Moines, Washington, on
August 14, 2020.
James E. Wilborn,
Acting Manager, Transport Standards
Branch, Policy and Innovation Division,
Aircraft Certification Service.
[FR Doc. 2020–18309 Filed 9–3–20; 8:45 am]
BILLING CODE 4910–13–P
VerDate Sep<11>2014
15:57 Sep 03, 2020
Jkt 250001
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 71
[Docket No. FAA–2020–0651; Airspace
Docket No. 18–AAL–13]
RIN 2120–AA66
Proposed Amendment of Federal
Airway V–456
Federal Aviation
Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking
(NPRM).
AGENCY:
This action proposes to
amend Alaskan Federal Airway V–456
due to the pending decommissioning of
the Glenallen Non-Directional Beacon
(NDB) in east central Alaska, and the
cancellation of Federal Colored Airway
Green 11 (G–11) under Regional Docket
Number 20–AAL–4.
DATES: Comments must be received on
or before October 19, 2020.
ADDRESSES: Send comments on this
proposal to the U.S. Department of
Transportation, Docket Operations, 1200
New Jersey Avenue SE, West Building
Ground Floor, Room W12–140,
Washington, DC 20590; telephone:
1(800) 647–5527, or (202) 366–9826.
You must identify FAA Docket No.
FAA–2020–0651; Airspace Docket No.
18–AAL–13 at the beginning of your
comments. You may also submit
comments through the internet at
https://www.regulations.gov.
FAA Order 7400.11D, Airspace
Designations and Reporting Points, and
subsequent amendments can be viewed
online at https://www.faa.gov/air_
traffic/publications/. For further
information, you can contact the Rules
and Regulations Group, Federal
Aviation Administration, 800
Independence Avenue SW, Washington,
DC 20591; telephone: (202) 267–8783.
The Order is also available for
inspection at the National Archives and
Records Administration (NARA). For
information on the availability of FAA
Order 7400.11D at NARA, email:
fedreg.legal@nara.gov or go to https://
www.archives.gov/federal-register/cfr/
ibr-locations.html.
FOR FURTHER INFORMATION CONTACT:
Christopher McMullin, Rules and
Regulations Group, Office of Policy,
Federal Aviation Administration, 800
Independence Avenue SW, Washington,
DC 20591; telephone: (202) 267–8783.
SUPPLEMENTARY INFORMATION:
SUMMARY:
PO 00000
Frm 00003
Fmt 4702
Sfmt 4702
Authority for This Rulemaking
The FAA’s authority to issue rules
regarding aviation safety is found in
Title 49 of the United States Code.
Subtitle I, Section 106 describes the
authority of the FAA Administrator.
Subtitle VII, Aviation Programs,
describes in more detail the scope of the
agency’s authority. This rulemaking is
promulgated under the authority
described in Subtitle VII, Part A,
Subpart I, Section 40103. Under that
section, the FAA is charged with
prescribing regulations to assign the use
of the airspace necessary to ensure the
safety of aircraft and the efficient use of
airspace. This regulation is within the
scope of that authority as it would
modify the route structure as necessary
to preserve the safe and efficient flow of
air traffic within the National Airspace
System.
Comments Invited
Interested parties are invited to
participate in this proposed rulemaking
by submitting such written data, views,
or arguments as they may desire.
Comments that provide the factual basis
supporting the views and suggestions
presented are particularly helpful in
developing reasoned regulatory
decisions on the proposal. Comments
are specifically invited on the overall
regulatory, aeronautical, economic,
environmental, and energy-related
aspects of the proposal.
Communications should identify both
docket numbers (FAA Docket No. FAA–
2020–0651; Airspace Docket No. 18–
AAL–13) and be submitted in triplicate
to the Docket Management Facility (see
ADDRESSES section for address and
phone number). You may also submit
comments through the internet at
https://www.regulations.gov.
Commenters wishing the FAA to
acknowledge receipt of their comments
on this action must submit with those
comments a self-addressed, stamped
postcard on which the following
statement is made: ‘‘Comments to FAA
Docket No. FAA–2020–0651; Airspace
Docket No. 18–AAL–13.’’ The postcard
will be date/time stamped and returned
to the commenter.
All communications received on or
before the specified comment closing
date will be considered before taking
action on the proposed rule. The
proposal contained in this action may
be changed in light of comments
received. All comments submitted will
be available for examination in the
public docket both before and after the
comment closing date. A report
summarizing each substantive public
contact with FAA personnel concerned
E:\FR\FM\04SEP1.SGM
04SEP1
Agencies
[Federal Register Volume 85, Number 173 (Friday, September 4, 2020)]
[Proposed Rules]
[Pages 55198-55200]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-18309]
========================================================================
Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
========================================================================
Federal Register / Vol. 85, No. 173 / Friday, September 4, 2020 /
Proposed Rules
[[Page 55198]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA-2020-0404; Notice No. 25-20-04-SC]
Special Conditions: B/E Aerospace, Bombardier Model CL-600-2B16
(604 Variant) Airplane; Seats With Pretensioner Restraint Systems
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed special conditions.
-----------------------------------------------------------------------
SUMMARY: This action proposes special conditions for the Bombardier
Inc. (Bombardier) Model CL-600-2B16 (604 variant) airplane. This
airplane, as modified by B/E Aerospace, 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 a 3-point shoulder harness incorporating a
pretensioner restraint system. The applicable airworthiness regulations
do not contain adequate or appropriate safety standards for this design
feature. 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: Send comments on or before October 19, 2020.
ADDRESSES: Send comments identified by Docket No. FAA-2020-0404 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 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: Shannon Lennon, Airframe and Cabin
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:
Comments Invited
The FAA invites 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.
The FAA will consider all comments received by the closing date for
comments. The FAA may change these special conditions based on the
comments received.
Background
On June 7, 2019, B/E Aerospace applied for a supplemental type
certificate for seats with 3-point harness and pretensioner restraint
systems in Bombardier Model CL-600-2B16 (604 variant) airplanes. The
604 variant is a derivative of the Bombardier Model CL-600-2B16
airplane currently approved under Type Certificate No. A21EA. This
airplane variant is a twin-engine, transport category airplane with
seating for 22 passengers, including crew, and a maximum take-off
weight of 47,600 pounds.
Type Certification Basis
Under the provisions of title 14, Code of Federal Regulations (14
CFR) 21.101, B/E Aerospace must show that the Bombardier Model CL-600-
2B16 (604 variant) airplane, as changed, continues to meet the
applicable provisions of the regulations listed in Type Certificate No.
A21EA 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 (e.g., 14 CFR part 25) do not contain adequate or
appropriate safety standards for the Bombardier Model CL-600-2B16 (604
variant) 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 applicant apply for a supplemental type
certificate to modify any other model included on the same type
certificate 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 Bombardier Model CL-600-2B16 (604 variant) 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.
[[Page 55199]]
Novel or Unusual Design Features
The Bombardier Model CL-600-2B16 (604 variant) airplane will
incorporate the following novel or unusual design features: Seats with
a 3-point shoulder harness incorporating a pretensioner restraint
system to prevent head injuries.
Discussion
B/E Aerospace has developed a system in which a pretensioning
automotive retractor eliminates slack in the 3-point shoulder harness,
pulling the occupant back into the seat prior to impact. This has the
effect of reducing forward translation of the occupant (reduced head
arc), while reducing the loads in the shoulder harness. B/E Aerospace
will install, in Bombardier Model CL-600-2B16 (604 variant) airplanes,
seats that incorporate a 3-point harness and pretensioner restraint
system to protect seat occupants from head injuries.
Over the past 10 years, multiple sensor-driven systems have been
installed in various airplanes to meet improved crashworthiness
regulations. A sensor-driven system is defined as any system that
activates due to a signal sent by an impact-triggered inertial sensor.
These types of systems include a lap-belt airbag, a structure-mounted
airbag, and a 3-point harness and pretensioner restraint system.
Shoulder harnesses have been widely used on flight-attendant seats,
flight-deck seats, in business jets, and in general-aviation airplanes
to reduce occupant head injury in the unlikely event of an emergency
landing. Special conditions, pertinent regulations, and guidance have
been published, relating to other or existing restraint systems.
However, the use of a pretensioner restraint system with a 3-point
harness on transport airplane seats is a novel design.
Pretensioner technology involves a step change in loading
experienced by the occupant for impacts below and above that at which
the device activates, because the upper torso excursion would be
interrupted by activation of the shoulder harness. This could result in
the head-injury criteria being higher at an intermediate impact
condition than that resulting from the maximum impact condition
corresponding to the test conditions specified in Sec. 25.562.
The ideal triangular maximum-severity pulse is defined in Advisory
Circular 25.562-1B Dynamic Evaluation of Seat Restraint Systems and
Occupant Protection on Transport Airplanes with Change 1, dated January
10, 2006. For evaluating and testing less-severe pulses to assess the
effectiveness of the pretensioner 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
these special conditions.
Additionally, the pretensioner might not provide protection, after
actuation, during secondary impacts. Therefore, the case where a small
impact is followed by a large impact should be addressed. If the
minimum deceleration severity at which the pretensioner is set to
activate is unnecessarily low, the protection offered by the
pretensioner may be lost by the time a second larger impact occurs.
The existing regulations do not adequately address seats with
pretensioner restraint systems. Therefore, the proposed configuration
requires special conditions.
Special conditions 1 through 5 address ensuring that the
pretensioner system activates when intended, to provide the necessary
protection of occupants. This includes protection of a range of
occupants under various accident conditions. Special conditions 6
through 11 address maintenance and reliability of the pretensioner
system, including any outside influences on the mechanism, to ensure it
functions as intended.
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.
Applicability
As discussed above, these special conditions are applicable to the
Bombardier Model CL-600-2B16 (604 variant) airplanes as modified by B/E
Aerospace. Should B/E Aerospace apply at a later date for a
supplemental type certificate to modify any other model included on
Type Certificate No. A21EA to incorporate 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 of airplanes. It is not a rule of general applicability
and affects only the applicant who applied to the FAA for approval of
these features on the airplane.
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, and
44704.
The Proposed Special Conditions
Accordingly, the Federal Aviation Administration (FAA) proposes the
following special conditions as part of the type certification basis
for Bombardier Model CL-600-2B16 (604 variant) airplanes as modified by
B/E Aerospace.
In addition to the requirements of Sec. Sec. 25.562, forward-
facing passenger seats incorporating pretensioner restraint systems
must meet the following:
1. Head Injury Criteria--The Head Injury Criteria value must not
exceed 1,000 units at any condition at which the pretensioner does or
does not deploy, up to the maximum severity pulse that corresponds to
the test conditions specified in Sec. 25.562. Tests must be performed
to demonstrate this, taking into account any necessary tolerances for
deployment.
2. Protection during Secondary Impacts--The pretensioner activation
setting must be demonstrated to maximize the probability of the
protection being available when needed, considering secondary impacts.
3. Protection of Occupants Other than 50th Percentile--Protection
of occupants for a range of stature from a 2-year-old child to a 95th
percentile male must be shown. For shoulder harnesses that include
pretensioners, protection of occupants other than a 50th percentile
male may be shown by test or analysis. In addition, the pretensioner
must not introduce a hazard to passengers due to the following seating
configurations:
a. The seat occupant is holding an infant.
b. The seat occupant is a child in a child restraint device.
c. The seat occupant is a pregnant woman.
4. Occupants Adopting the Brace Position--Occupants in the
traditional brace position when the pretensioner activates must not
experience adverse effects from the pretensioner activation.
5. Inadvertent Pretensioner Actuation
a. The probability of inadvertent pretensioner actuation must be
shown to be extremely remote (i.e., average
[[Page 55200]]
probability per flight hour of less than 10-7).
b. The system must be shown not susceptible to inadvertent
pretensioner actuation as a result of wear and tear, or inertia loads
resulting from in-flight or ground maneuvers likely to be experienced
in service.
c. The seated occupant must not be seriously injured as a result of
inadvertent pretensioner actuation.
d. Inadvertent pretensioner activation must not cause a hazard to
the airplane nor cause serious injury to anyone who may be positioned
close to the retractor or belt (e.g., seated in an adjacent seat or
standing adjacent to the seat).
6. Availability of the Pretensioner Function Prior to Flight--The
design must provide means for a crewmember to verify the availability
of the pretensioner function prior to each flight, or the probability
of failure of the pretensioner function must be demonstrated to be
extremely remote (i.e., average probability per flight hour of less
than 10-7) between inspection intervals.
7. Incorrect Seatbelt Orientation--The system design must ensure
that any incorrect orientation (twisting) of the seatbelt does not
compromise the pretensioner protection function.
8. Contamination Protection--The pretensioner mechanisms and
controls must be protected from external contamination associated with
that which could occur on or around passenger seating.
9. Prevention of Hazards--The pretensioner system must not induce a
hazard to passengers in case of fire, nor create a fire hazard if
activated.
10. Functionality after Loss of Power--The system must function
properly after loss of normal airplane electrical power, and after a
transverse separation in the fuselage at the most critical location. A
separation at the location of the system does not have to be
considered.
11. High-intensity Radiated Fields (HIRF) and Lightning
Protection--For airplanes that do not already incorporate 14 CFR
25.1316 and 25.1317 into their certification basis, the equipment must
meet the applicable requirements of Sec. Sec. 25.1316 and 25.1317.
Electrostatic discharge must also be considered in the design and
testing of the equipment.
Issued in Des Moines, Washington, on August 14, 2020.
James E. Wilborn,
Acting Manager, Transport Standards Branch, Policy and Innovation
Division, Aircraft Certification Service.
[FR Doc. 2020-18309 Filed 9-3-20; 8:45 am]
BILLING CODE 4910-13-P