Special Conditions: The Boeing Company, Model 767-300; Seats With Inflatable Lapbelts, 1618-1622 [2012-350]
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used, there must be a landing gear
position indicator easily visible to the
pilot or to the appropriate crew
members (as well as necessary devices
to actuate the indicator) to indicate
without ambiguity that the retractable
units and their associated doors are
secured in the extended (or retracted)
position. The means must be designed
as follows:
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(5) The system used to generate the
aural warning must be designed to
minimize false or inappropriate alerts.
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(7) A flightcrew alert must be
provided whenever the landing gear
position is not consistent with the
landing gear selector lever position.
(f) Protection of equipment on landing
gear and in wheel wells. Equipment that
is essential to the safe operation of the
airplane and that is located on the
landing gear and in wheel wells must be
protected from the damaging effects of—
(1) A bursting tire;
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(3) Possible wheel brake temperatures.
3. Amend § 25.773 by revising
paragraph (b)(2) and adding paragraphs
(b)(3) and (4) to read as follows:
■
§ 25.773
Pilot compartment view.
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(b) * * *
(2) No single failure of the systems
used to provide the view required by
paragraph (b)(1) of this section must
cause the loss of that view by both pilots
in the specified precipitation
conditions.
(3) The first pilot must have a window
that—
(i) Is openable under the conditions
prescribed in paragraph (b)(1) of this
section when the cabin is not
pressurized;
(ii) Provides the view specified in
paragraph (b)(1) of this section; and
(iii) Provides sufficient protection
from the elements against impairment of
the pilot’s vision.
(4) The openable window specified in
paragraph (b)(3) of this section need not
be provided if it is shown that an area
of the transparent surface will remain
clear sufficient for at least one pilot to
land the airplane safely in the event of—
(i) Any system failure or combination
of failures which is not extremely
improbable, in accordance with
§ 25.1309, under the precipitation
conditions specified in paragraph (b)(1)
of this section.
(ii) An encounter with severe hail,
birds, or insects.
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Issued in Washington, DC, on December
27, 2011.
Michael P. Huerta,
Acting Administrator.
[FR Doc. 2012–360 Filed 1–10–12; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA–2012–0009; Special
Conditions No. 25–454–SC]
Special Conditions: The Boeing
Company, Model 767–300; Seats With
Inflatable Lapbelts
Federal Aviation
Administration (FAA), DOT.
ACTION: Final special conditions; request
for comments.
AGENCY:
These special conditions are
issued for the Boeing Model 767–300
series airplanes. These airplanes will
have a novel or unusual design feature
associated with seats with inflatable
lapbelts. 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: The effective date of these
special conditions is January 5, 2012.
We must receive your comments by
February 27, 2012.
ADDRESSES: Send comments identified
by docket number FAA–2012–0009
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
8 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
SUMMARY:
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commenter provides. Using the search
function of the docket Web site, 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),
as well as at https://DocketsInfo.dot.gov/
.
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 the 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: John
Shelden, FAA, Airframe and Cabin
Safety Branch, ANM–115, Transport
Airplane Directorate, Aircraft
Certification Service, 1601 Lind Avenue
SW., Renton, Washington 98057–3356;
telephone (425) 227–2785; facsimile
(425) 227–1320.
SUPPLEMENTARY INFORMATION: The FAA
has determined that notice of, and
opportunity for prior public comment
on, these special conditions are
impracticable because these procedures
would significantly delay issuance of
the design approval and thus delivery of
the affected aircraft. In addition, the
substance of these special conditions
has been subject to the public comment
process in several prior instances with
no substantive comments received. The
FAA therefore finds that good cause
exists for making these special
conditions effective upon issuance.
Comments Invited
We invite interested people to take
part in this rulemaking by sending
written comments, data, or views. The
most helpful comments reference a
specific portion of the special
conditions, explain the reason for any
recommended change, and include
supporting data.
We will consider all comments we
receive by the closing date for
comments. We may change these special
conditions based on the comments we
receive.
Background
On April 19, 2011, The Boeing
Company (hereafter referred to as
‘‘Boeing’’) applied for a change to Type
Certificate No. A1NM for the
installation of inflatable lapbelts on
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Boeing Model 767–300 series airplanes.
The Model 767–300 is a transport
category airplane powered by two turbofan engines with a maximum passenger
capacity of 290 and a maximum takeoff
weight of 351,600 pounds. These special
conditions are to allow installation of
inflatable lapbelts for head injury
protection on certain seats in the 767–
300 series airplanes similar to Special
Conditions No. 25–187A–SC for Boeing
Model 777 series airplanes and Special
Conditions No. 25–386–SC for Boeing
Model 737 series airplanes.
The inflatable lapbelt is designed to
limit occupant forward excursion in the
event of an accident. This will reduce
the potential for head injury, thereby
reducing the head injury criteria (HIC)
measurement. The inflatable lapbelt
behaves similarly to an automotive
inflatable airbag, but in this case the
airbag is integrated into the lapbelt and
inflates away from the seated occupant.
While inflatable airbags are now
standard in the automotive industry, the
use of an inflatable lapbelt is novel for
commercial aviation.
Title 14, Code of Federal Regulations
(14 CFR) 121.311(j) requires that all
passenger and flight attendant seats in
transport category airplanes meet the
requirements of § 25.562 in effect on or
after June 16, 1988, if they were type
certificated after January 1, 1958,
manufactured on or after October 27,
2009, and operated under part 121 rules
in passenger-carrying operations.
Boeing is required to show
compliance with certain aspects of
§ 25.562 as specified per Type
Certificate Data Sheet (TCDS) A1NM for
the Model 767–300 (hereafter referred to
as ‘‘767–300’’) series airplanes.
However, 767–300 series airplanes
manufactured on or after October 27,
2009, operated under part 121, must
meet all of the requirements of § 25.562
for passenger and flight attendant seats.
Thus, it is in the interest of installers to
show full compliance to § 25.562, so
that an operator under part 121 may be
able to use the aircraft without having
to do additional certification work. It is
also noted that some foreign civil
airworthiness authorities have invoked
these same operator requirements in the
form of airworthiness directives.
Section 25.785 requires that
occupants be protected from head injury
by either the elimination of any
injurious object within the striking
radius of the head, or by padding.
Traditionally, this has required a set
back of 35 inches from any bulkhead or
other rigid interior feature or, where not
practical, specified types of padding.
The relative effectiveness of these
means of injury protection was not
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quantified. With the adoption of
Amendment 25–64 to 14 CFR part 25,
specifically § 25.562, a new standard
that quantifies required head injury
protection was created.
Section 25.562 specifies that each seat
type design approved for crew or
passenger occupancy during takeoff and
landing must be shown to be compliant
by successful completion of dynamic
tests or by rational analysis based on
dynamic tests of a similar type seat. In
particular, the regulations require that
persons not suffer serious head injury
under the conditions specified in the
tests, and that protection must be
provided, or the seat be designed, so
that the head impact does not exceed a
HIC of 1000 units. While the test
conditions described for HIC are
detailed and specific, it is the intent of
the requirement that an adequate level
of head injury protection be provided
for passengers in a severe crash.
Because §§ 25.562 and 25.785 and
associated guidance do not adequately
address seats with inflatable lapbelts,
the FAA recognizes that appropriate
pass/fail criteria need to be developed
that do fully address the safety concerns
specific to occupants of these seats.
Type Certification Basis
Under the provisions of § 21.101,
Boeing must show that the 767–300, as
changed, continues to meet the
applicable provisions of the regulations
incorporated by reference in Type
Certificate No. A1NM or the applicable
regulations in effect on the date of
application for the change. The
regulations incorporated by reference in
the type certificate are commonly
referred to as the ‘‘original type
certification basis.’’ The regulations
incorporated by reference in Type
Certificate No. A1NM are as follows:
part 25 of the Federal Aviation
Regulations as amended by
Amendments 25–1 through 25–37,
except where superseded. The U.S. type
certification basis for the 767–300 is
established in accordance with 14 CFR
21.29 and 21.17 and the type
certification application date. The U.S.
type certification basis is listed in TCDS
No. A1NM.
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 Boeing Model 767–300 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
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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, the special conditions
would also apply to the other model.
In addition to the applicable
airworthiness regulations and special
conditions, the 767–300 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.
Novel or Unusual Design Features
The 767–300 will incorporate the
following novel or unusual design
features: Boeing is proposing to install
an inflatable lapbelt on certain seats of
the 767–300 series airplanes in order to
reduce the potential for head injury in
the event of an accident. The inflatable
lapbelt works similarly to an automotive
airbag, except that the airbag is
integrated with the lapbelt of the
restraint system.
The CFR states the performance
criteria for head injury protection in
objective terms. However, none of these
criteria are adequate to address the
specific issues raised concerning seats
with inflatable lapbelts. The FAA has
therefore determined that, in addition to
the requirements of 14 CFR part 25,
special conditions are needed to address
requirements particular to installation of
seats with inflatable lapbelts.
Accordingly, in addition to the
passenger injury criteria specified in
§ 25.785, these special conditions are
proposed for the Boeing Model 767–300
series airplanes equipped with
inflatable lapbelts. Other conditions
may be developed, as needed, based on
further FAA review and discussions
with the manufacturer and civil aviation
authorities.
Discussion
From the standpoint of a passenger
safety system, the inflatable lapbelt is
unique in that it is both an active and
entirely autonomous device. While the
automotive industry has good
experience with inflatable airbags, the
conditions of use and reliance on the
inflatable lapbelt as the sole means of
injury protection are quite different. In
automobile installations, the airbag is a
supplemental system and works in
conjunction with an upper torso
restraint. In addition, the crash event is
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more definable and of typically shorter
duration, which can simplify the
activation logic. The airplane operating
environment is also quite different from
automobiles and includes the potential
for greater wear and tear and
unanticipated abuse conditions (due to
galley loading, passenger baggage, etc.);
airplanes also operate where exposure
to high intensity electromagnetic fields
could affect the activation system.
The inflatable lapbelt has two
potential advantages over other means
of head impact protection. First, it can
provide significantly greater protection
than would be expected with energyabsorbing pads, and second, it can
provide essentially equivalent
protection for occupants of all stature.
These are significant advantages from a
safety standpoint, since such devices
will likely provide a level of safety that
exceeds the minimum standards of the
Federal aviation regulations.
Conversely, inflatable lapbelts in
general are active systems and must be
relied upon to activate properly when
needed, as opposed to an energyabsorbing pad or upper torso restraint
that is passive, and always available.
Therefore, the potential advantages
must be balanced against these and
other potential disadvantages in order to
develop standards for this design
feature.
The FAA has considered the
installation of inflatable lapbelts to have
two primary safety concerns: First, that
they perform properly under foreseeable
operating conditions, and second, that
they do not perform in a manner or at
such times as would constitute a hazard
to the airplane or occupants. This latter
point has the potential to be the more
rigorous of the requirements, owing to
the active nature of the system.
The inflatable lapbelt will rely on
electronic sensors for signaling and
pyrotechnic charges for activation so
that it is available when needed. These
same devices could be susceptible to
inadvertent activation, causing
deployment in a potentially unsafe
manner. The consequences of such
deployment, as well as failure to deploy,
must be considered in establishing the
reliability of the system. Boeing must
substantiate that the effects of an
inadvertent deployment in flight are
either not a hazard to the airplane, or
that such deployment is an extremely
improbable occurrence (less than 10¥9
per flight hour). The effect of an
inadvertent deployment on a passenger
or crewmember that might be positioned
close to the inflatable lapbelt should
also be considered. The person could be
either standing or sitting. A minimum
reliability level will have to be
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established for this case, depending
upon the consequences, even if the
effect on the airplane is negligible.
The potential for an inadvertent
deployment could be increased as a
result of conditions in service. The
installation must take into account wear
and tear so that the likelihood of an
inadvertent deployment is not increased
to an unacceptable level. In this context,
an appropriate inspection interval and
self-test capability are considered
necessary. Other outside influences are
lightning and high intensity radiated
fields (HIRF). Existing regulations
regarding lightning, § 25.1316, and
existing HIRF special conditions for the
767–300 series airplanes, Special
Conditions No. 25–ANM–18, are
applicable. For the purposes of
compliance with those conditions, if
inadvertent deployment could cause a
hazard to the airplane, the inflatable
lapbelt is considered a critical system; if
inadvertent deployment could cause
injuries to persons, the inflatable lapbelt
should be considered an essential
system. Finally, the inflatable lapbelt
installation should be protected from
the effects of fire, so that an additional
hazard is not created by, for example, a
rupture of the pyrotechnic squib.
In order to be an effective safety
system, the inflatable lapbelt must
function properly and must not
introduce any additional hazards to
occupants as a result of its functioning.
There are several areas where the
inflatable lapbelt differs from traditional
occupant protection systems and
requires special conditions to ensure
adequate performance.
Because the inflatable lapbelt is
essentially a single use device, there is
the potential that it could deploy under
crash conditions that are not sufficiently
severe as to require head injury
protection from the inflatable lapbelt.
Since an actual crash is frequently
composed of a series of impacts before
the airplane comes to rest, this could
render the inflatable lapbelt useless if a
larger impact follows the initial impact.
This situation does not exist with
energy absorbing pads or upper torso
restraints, which tend to provide
continuous protection regardless of
severity or number of impacts in a crash
event. Therefore, the inflatable lapbelt
installation should be such that the
inflatable lapbelt will provide
protection when it is required, by not
expending its protection during a less
severe impact. Also, it is possible to
have several large impact events during
the course of a crash, but there will be
no requirement for the inflatable lapbelt
to provide protection for multiple
impacts.
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Since each occupant’s restraint
system provides protection for that
occupant only, the installation must
address seats that are unoccupied. It
will be necessary to show that the
required protection is provided for each
occupant regardless of the number of
occupied seats, and considering that
unoccupied seats may have lapbelts that
are active.
The inflatable lap belt should be
effective for a wide range of occupants.
The FAA has historically considered the
range from the fifth percentile female to
the ninety-fifth percentile male as the
range of occupants that must be taken
into account. In this case, the FAA is
proposing consideration of a broader
range of occupants, due to the nature of
the lapbelt installation and its close
proximity to the occupant. In a similar
vein, these persons could have assumed
the brace position for those accidents
where an impact is anticipated. Test
data indicate that occupants in the brace
position do not require supplemental
protection, and so it would not be
necessary to show that the inflatable
lapbelt will enhance the brace position.
However, the inflatable lapbelt must not
introduce a hazard in that case when
deploying into the seated, braced
occupant.
Another area of concern is the use of
seats, so equipped, by children whether
lap-held, in approved child safety seats,
or occupying the seat directly. Although
specifically prohibited by the FAA
operating regulations, the use of the
supplementary loop belt (‘‘belly belt’’)
may be required by other civil aviation
authorities, and should also be
considered with the end goal of meeting
those regulations. Similarly, if the seat
is occupied by a pregnant woman, the
installation needs to address such usage,
either by demonstrating that it will
function properly, or by adding
appropriate limitation on usage.
Since the inflatable lapbelt will be
electrically powered, there is the
possibility that the system could fail
due to a separation in the fuselage.
Since this system is intended as crash/
post-crash protection means, failure due
to fuselage separation is not acceptable.
As with emergency lighting, the system
should function properly if such a
separation occurs at any point in the
fuselage.
Since the inflatable lapbelt is likely to
have a large volume displacement, the
inflated bag could potentially impede
egress of passengers. Since the bag
deflates to absorb energy, it is likely that
an inflatable lapbelt would be deflated
at the time that persons would be trying
to leave their seats. Nonetheless, it is
considered appropriate to specify a time
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interval after which the inflatable
lapbelt may not impede rapid egress.
Ten seconds has been chosen as a
reasonable time since this corresponds
to the maximum time allowed for an
exit to be openable (§ 25.809). In
actuality, it is unlikely that an exit
would be prepared by a flight attendant
this quickly in an accident severe
enough to warrant deployment of the
inflatable lapbelt, and the inflatable
lapbelt will likely deflate much quicker
than ten seconds.
This potential impediment to rapid
egress is even more critical at the seats
installed in the emergency exit rows.
Section 25.813 requires access to the
exit from the main aisle in the form of
an unobstructed passageway and no
interference in opening the exit. The
restraint system must not create an
impediment to the access to, and the
opening of, the exit. In some cases, the
passenger is the one who will open the
exit, such as a Type III over wing hatch.
These lapbelts should be evaluated in
the exit row under existing regulations
(§§ 25.809 and 25.813) and guidance
material. The inflatable lapbelts must
also be evaluated in post crash
conditions and should be evaluated
using representative restraint systems in
the bag-deployed condition. This
evaluation would include reviewing the
access to and opening of the exit,
specifically for obstructions in the
egress path and any interferences in
opening the exit. Each unique interior
configuration must be considered, for
example, passageway width, single or
dual passageways with outboard seat
removed, etc. If the restraint creates any
obstruction or interference, it is likely
that it could impede the rapid egress of
the airplane. Project-specific guidance is
likely necessary if these restraint
systems are installed at exit door rows.
The current special conditions for the
Boeing 777 series airplanes, Special
Conditions No. 25–187A–SC, were
amended to address flammability of the
airbag material. During the development
of the inflatable lapbelt, the
manufacturer was unable to develop a
fabric that would meet the inflation
requirements for the bag and the
flammability requirements of part I,
paragraph (a)(1)(ii), of appendix F to
part 25. The fabrics that were developed
that met the flammability requirement
did not produce acceptable deployment
characteristics. However, the
manufacturer was able to develop a
fabric that meets the less stringent
flammability requirements of part I,
paragraph (a)(1)(iv), of appendix F to
part 25 and has acceptable deployment
characteristics.
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Part I of appendix F to part 25
specifies the flammability requirements
for interior materials and components.
There is no reference to inflatable
restraint systems in appendix F, because
such devices did not exist at the time
the flammability requirements were
written. The existing requirements are
based on both material types, as well as
use, and have been specified in light of
the state-of-the-art of materials available
to perform a given function. In the
absence of a specific reference, the
default requirement would be for the
type of material used to construct the
inflatable restraint, which is a fabric in
this case. However, in writing special
conditions, the FAA must also consider
the use of the material, and whether the
default requirement is appropriate. In
this case, the specialized function of the
inflatable restraint means that highly
specialized materials are needed. The
standard normally applied to fabrics is
a 12-second vertical ignition test.
However, materials that meet this
standard do not perform adequately as
inflatable restraints. Since the safety
benefit of the inflatable restraint is very
significant, the flammability standard
appropriate for these devices should not
screen out suitable materials, thereby
effectively eliminating use of inflatable
restraints. The FAA will need to
establish a balance between the safety
benefit of the inflatable restraint and its
flammability performance. At this time,
the 2.5-inch per minute horizontal test
is considered to provide that balance.
As the state-of-the-art in materials
progresses (which is expected), the FAA
may change this standard in subsequent
special conditions to account for
improved materials.
The following special conditions can
be characterized as addressing either the
safety performance of the system or the
system’s integrity against inadvertent
activation. Because a crash requiring use
of the inflatable lapbelts is a relatively
rare event, and because the
consequences of an inadvertent
activation are potentially quite severe,
these latter requirements are probably
the more rigorous from a design
standpoint.
Finally, it should be noted that the
special conditions are applicable to the
inflatable lapbelt system as installed.
The special conditions are not an
installation approval. Therefore, while
the special conditions relate to each
such system installed, the overall
installation approval is a separate
finding and must consider the combined
effects of all such systems installed.
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Applicability
As discussed above, these special
conditions are applicable to the 767–
300. 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,
the special conditions would apply to
that model as well.
Conclusion
This action affects only certain novel
or unusual design features on one model
of airplanes. It is not a rule of general
applicability.
The substance of these special
conditions has been subjected to the
notice and comment period in several
prior instances and has been derived
without substantive change from those
previously issued. It is unlikely that
prior public comment would result in a
significant change from the substance
contained herein. Therefore, because a
delay would significantly affect the
certification of the airplane, which is
imminent, the FAA has determined that
prior public notice and comment are
unnecessary and impracticable, and
good cause exists for adopting these
special conditions upon issuance. The
FAA is requesting comments to allow
interested persons to submit views that
may not have been submitted in
response to the prior opportunities for
comment described above.
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
767–300 airplanes.
1. Seats with Inflatable Lapbelts. It
must be shown that the inflatable
lapbelt will deploy and provide
protection under crash conditions
where it is necessary to prevent serious
head injury. The means of protection
must take into consideration a range of
stature from a two-year-old child to a
ninety-fifth percentile male. The
inflatable lapbelt must provide a
consistent approach to energy
absorption throughout that range of
occupants. In addition, the following
situations must be considered:
a. The seat occupant is holding an
infant.
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b. The seat occupant is a child in a
child restraint device.
c. The seat occupant is a child not
using a child restraint device.
d. The seat occupant is a pregnant
woman.
2. The inflatable lapbelt must provide
adequate protection for each occupant
regardless of the number of occupants of
the seat assembly, considering that
unoccupied seats may have active
seatbelts.
3. The design must prevent the
inflatable lapbelt from being either
incorrectly buckled or incorrectly
installed such that the inflatable lapbelt
would not properly deploy.
Alternatively, it must be shown that
such deployment is not hazardous to the
occupant and will provide the required
head injury protection.
4. It must be shown that the inflatable
lapbelt system is not susceptible to
inadvertent deployment as a result of
wear and tear or inertial loads resulting
from in-flight or ground maneuvers
(including gusts and hard landings)
likely to be experienced in service.
5. Deployment of the inflatable lapbelt
must not introduce injury mechanisms
to the seated occupant or result in
injuries that could impede rapid egress.
This assessment should include an
occupant who is in the brace position
when it deploys and an occupant whose
belt is loosely fastened.
6. It must be shown that inadvertent
deployment of the inflatable lapbelt,
during the most critical part of the
flight, will either not cause a hazard to
the airplane or its occupants, or meets
the requirements of § 25.1309(b).
7. It must be shown that the inflatable
lapbelt will not impede rapid egress of
occupants 10 seconds after its
deployment.
8. The system must be protected from
lightning and HIRF. The threats
specified in existing regulations
regarding lightning, § 25.1316, and
existing HIRF special conditions for the
Boeing Model 767 series aircraft,
Special Conditions No. 25–ANM–18, are
incorporated by reference for the
purpose of measuring lightning and
HIRF protection. For the purposes of
complying with HIRF requirements, the
inflatable lapbelt system is considered a
‘‘critical system’’ if its deployment
could have a hazardous effect on the
airplane; otherwise, it is considered an
‘‘essential’’ system.
9. Inflatable lapbelts, once deployed,
must not adversely affect the emergency
lighting system (i.e., block proximity
lights to the extent that the lights no
longer meet their intended function).
10. The inflatable lapbelt must
function properly after loss of normal
VerDate Mar<15>2010
12:38 Jan 10, 2012
Jkt 226001
aircraft electrical power and after a
transverse separation of the fuselage at
the most critical location. A separation
at the location of the lapbelt does not
have to be considered.
11. It must be shown that the
inflatable lapbelt will not release
hazardous quantities of gas or
particulate matter into the cabin.
12. The inflatable lapbelt installation
must be protected from the effects of fire
such that no hazard to occupants will
result.
13. There must be a means for a
crewmember to verify the integrity of
the inflatable lapbelt activation system
prior to each flight, or it must be
demonstrated to operate reliably
between inspection intervals. The FAA
considers the loss of the airbag system
deployment function alone (i.e.,
independent of the conditional event
that requires the airbag system
deployment) to be a major failure
condition.
14. The inflatable material may not
have an average burn rate of greater than
2.5 inches/minute when tested using the
horizontal flammability test as defined
in 14 CFR part 25, appendix F, part I,
paragraph (b)(5).
Issued in Renton, Washington, on January
5, 2012.
Ali Bahrami,
Manager, Transport Airplane Directorate,
Aircraft Certification Service, ANM–100.
[FR Doc. 2012–350 Filed 1–10–12; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2011–1139; Directorate
Identifier 2011–CE–021–AD; Amendment
39–16911; AD 2011–27–09]
RIN 2120–AA64
Airworthiness Directives; Socata
Airplanes
Federal Aviation
Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule.
AGENCY:
We are adopting a new
airworthiness directive (AD) for Socata
Model TBM 700 airplanes. This AD
results from mandatory continuing
airworthiness information (MCAI)
issued by an aviation authority of
another country to identify and correct
an unsafe condition on an aviation
product. The MCAI describes the unsafe
condition as installation of the wrong
SUMMARY:
PO 00000
Frm 00032
Fmt 4700
Sfmt 4700
(switched) aileron control cables in the
wing. This unsafe condition could lead
to restricted movement of the aileron,
resulting in reduced control of the
airplane. We are issuing this AD to
require actions to address the unsafe
condition on these products.
DATES: This AD is effective February 15,
2012.
The Director of the Federal Register
approved the incorporation by reference
of certain publications listed in the AD
as of February 15, 2012.
ADDRESSES: You may examine the AD
docket on the Internet at https://
www.regulations.gov or in person at
Document Management Facility, U.S.
Department of Transportation, Docket
Operations, M–30, West Building
Ground Floor, Room W12–140, 1200
New Jersey Avenue SE., Washington,
DC 20590.
For service information identified in
this proposed AD, contact Socata—
Direction des Services—65921 Tarbes
Cedex 9—France; telephone +33 (0) 62
41 7300, fax +33 (0) 62 41 76 54, or for
North America: Socata North America,
7501 South Airport Road, North Perry
Airport (HWO), Pembroke Pines, Florida
33023; telephone: (954) 893–1400; fax:
(954) 964–4141; email:
mysocata@socata.daher.com; Internet:
https://mysocata.com. You may review
copies of the referenced service
information at the FAA, Small Airplane
Directorate, 901 Locust, Kansas City,
Missouri 64106. For information on the
availability of this material at the FAA,
call (816) 329–4148.
FOR FURTHER INFORMATION CONTACT:
Albert Mercado, Aerospace Engineer,
FAA, Small Airplane Directorate, 901
Locust, Room 301, Kansas City,
Missouri 64106; telephone: (816) 329–
4119; fax: (816) 329–4090; email:
albert.mercado@faa.gov.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed
rulemaking (NPRM) to amend 14 CFR
part 39 to include an AD that would
apply to the specified products. That
NPRM was published in the Federal
Register on October 21, 2011 (76 FR
65419). That NPRM proposed to correct
an unsafe condition for the specified
products. The MCAI states:
A TBM 700 operator reported a case of
inverted installation of aileron control cables
in the wing. The shortest cable was found
installed instead of the longest one on wing
tip side, with left hand (LH) threaded end in
upper section. This wrong installation could
have been caused by mistaken maintenance
data.
This condition, if not detected and
corrected, could lead to restricted movement
E:\FR\FM\11JAR1.SGM
11JAR1
Agencies
[Federal Register Volume 77, Number 7 (Wednesday, January 11, 2012)]
[Rules and Regulations]
[Pages 1618-1622]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-350]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA-2012-0009; Special Conditions No. 25-454-SC]
Special Conditions: The Boeing Company, Model 767-300; Seats With
Inflatable Lapbelts
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions; request for comments.
-----------------------------------------------------------------------
SUMMARY: These special conditions are issued for the Boeing Model 767-
300 series airplanes. These airplanes will have a novel or unusual
design feature associated with seats with inflatable lapbelts. 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: The effective date of these special conditions is January 5,
2012. We must receive your comments by February 27, 2012.
ADDRESSES: Send comments identified by docket number FAA-2012-0009
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 8 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 Web site, 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), as well as at https://DocketsInfo.dot.gov/.
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 the 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: John Shelden, FAA, Airframe and Cabin
Safety Branch, ANM-115, Transport Airplane Directorate, Aircraft
Certification Service, 1601 Lind Avenue SW., Renton, Washington 98057-
3356; telephone (425) 227-2785; facsimile (425) 227-1320.
SUPPLEMENTARY INFORMATION: The FAA has determined that notice of, and
opportunity for prior public comment on, these special conditions are
impracticable because these procedures would significantly delay
issuance of the design approval and thus delivery of the affected
aircraft. In addition, the substance of these special conditions has
been subject to the public comment process in several prior instances
with no substantive comments received. The FAA therefore finds that
good cause exists for making these special conditions effective upon
issuance.
Comments Invited
We invite interested people to take part in this rulemaking by
sending written comments, data, or views. The most helpful comments
reference a specific portion of the special conditions, explain the
reason for any recommended change, and include supporting data.
We will consider all comments we receive by the closing date for
comments. We may change these special conditions based on the comments
we receive.
Background
On April 19, 2011, The Boeing Company (hereafter referred to as
``Boeing'') applied for a change to Type Certificate No. A1NM for the
installation of inflatable lapbelts on
[[Page 1619]]
Boeing Model 767-300 series airplanes. The Model 767-300 is a transport
category airplane powered by two turbo-fan engines with a maximum
passenger capacity of 290 and a maximum takeoff weight of 351,600
pounds. These special conditions are to allow installation of
inflatable lapbelts for head injury protection on certain seats in the
767-300 series airplanes similar to Special Conditions No. 25-187A-SC
for Boeing Model 777 series airplanes and Special Conditions No. 25-
386-SC for Boeing Model 737 series airplanes.
The inflatable lapbelt is designed to limit occupant forward
excursion in the event of an accident. This will reduce the potential
for head injury, thereby reducing the head injury criteria (HIC)
measurement. The inflatable lapbelt behaves similarly to an automotive
inflatable airbag, but in this case the airbag is integrated into the
lapbelt and inflates away from the seated occupant. While inflatable
airbags are now standard in the automotive industry, the use of an
inflatable lapbelt is novel for commercial aviation.
Title 14, Code of Federal Regulations (14 CFR) 121.311(j) requires
that all passenger and flight attendant seats in transport category
airplanes meet the requirements of Sec. 25.562 in effect on or after
June 16, 1988, if they were type certificated after January 1, 1958,
manufactured on or after October 27, 2009, and operated under part 121
rules in passenger-carrying operations.
Boeing is required to show compliance with certain aspects of Sec.
25.562 as specified per Type Certificate Data Sheet (TCDS) A1NM for the
Model 767-300 (hereafter referred to as ``767-300'') series airplanes.
However, 767-300 series airplanes manufactured on or after October 27,
2009, operated under part 121, must meet all of the requirements of
Sec. 25.562 for passenger and flight attendant seats. Thus, it is in
the interest of installers to show full compliance to Sec. 25.562, so
that an operator under part 121 may be able to use the aircraft without
having to do additional certification work. It is also noted that some
foreign civil airworthiness authorities have invoked these same
operator requirements in the form of airworthiness directives.
Section 25.785 requires that occupants be protected from head
injury by either the elimination of any injurious object within the
striking radius of the head, or by padding. Traditionally, this has
required a set back of 35 inches from any bulkhead or other rigid
interior feature or, where not practical, specified types of padding.
The relative effectiveness of these means of injury protection was not
quantified. With the adoption of Amendment 25-64 to 14 CFR part 25,
specifically Sec. 25.562, a new standard that quantifies required head
injury protection was created.
Section 25.562 specifies that each seat type design approved for
crew or passenger occupancy during takeoff and landing must be shown to
be compliant by successful completion of dynamic tests or by rational
analysis based on dynamic tests of a similar type seat. In particular,
the regulations require that persons not suffer serious head injury
under the conditions specified in the tests, and that protection must
be provided, or the seat be designed, so that the head impact does not
exceed a HIC of 1000 units. While the test conditions described for HIC
are detailed and specific, it is the intent of the requirement that an
adequate level of head injury protection be provided for passengers in
a severe crash.
Because Sec. Sec. 25.562 and 25.785 and associated guidance do not
adequately address seats with inflatable lapbelts, the FAA recognizes
that appropriate pass/fail criteria need to be developed that do fully
address the safety concerns specific to occupants of these seats.
Type Certification Basis
Under the provisions of Sec. 21.101, Boeing must show that the
767-300, as changed, continues to meet the applicable provisions of the
regulations incorporated by reference in Type Certificate No. A1NM or
the applicable regulations in effect on the date of application for the
change. The regulations incorporated by reference in the type
certificate are commonly referred to as the ``original type
certification basis.'' The regulations incorporated by reference in
Type Certificate No. A1NM are as follows: part 25 of the Federal
Aviation Regulations as amended by Amendments 25-1 through 25-37,
except where superseded. The U.S. type certification basis for the 767-
300 is established in accordance with 14 CFR 21.29 and 21.17 and the
type certification application date. The U.S. type certification basis
is listed in TCDS No. A1NM.
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 Boeing Model 767-300 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, the special conditions would also apply to the
other model.
In addition to the applicable airworthiness regulations and special
conditions, the 767-300 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 767-300 will incorporate the following novel or unusual design
features: Boeing is proposing to install an inflatable lapbelt on
certain seats of the 767-300 series airplanes in order to reduce the
potential for head injury in the event of an accident. The inflatable
lapbelt works similarly to an automotive airbag, except that the airbag
is integrated with the lapbelt of the restraint system.
The CFR states the performance criteria for head injury protection
in objective terms. However, none of these criteria are adequate to
address the specific issues raised concerning seats with inflatable
lapbelts. The FAA has therefore determined that, in addition to the
requirements of 14 CFR part 25, special conditions are needed to
address requirements particular to installation of seats with
inflatable lapbelts.
Accordingly, in addition to the passenger injury criteria specified
in Sec. 25.785, these special conditions are proposed for the Boeing
Model 767-300 series airplanes equipped with inflatable lapbelts. Other
conditions may be developed, as needed, based on further FAA review and
discussions with the manufacturer and civil aviation authorities.
Discussion
From the standpoint of a passenger safety system, the inflatable
lapbelt is unique in that it is both an active and entirely autonomous
device. While the automotive industry has good experience with
inflatable airbags, the conditions of use and reliance on the
inflatable lapbelt as the sole means of injury protection are quite
different. In automobile installations, the airbag is a supplemental
system and works in conjunction with an upper torso restraint. In
addition, the crash event is
[[Page 1620]]
more definable and of typically shorter duration, which can simplify
the activation logic. The airplane operating environment is also quite
different from automobiles and includes the potential for greater wear
and tear and unanticipated abuse conditions (due to galley loading,
passenger baggage, etc.); airplanes also operate where exposure to high
intensity electromagnetic fields could affect the activation system.
The inflatable lapbelt has two potential advantages over other
means of head impact protection. First, it can provide significantly
greater protection than would be expected with energy-absorbing pads,
and second, it can provide essentially equivalent protection for
occupants of all stature. These are significant advantages from a
safety standpoint, since such devices will likely provide a level of
safety that exceeds the minimum standards of the Federal aviation
regulations. Conversely, inflatable lapbelts in general are active
systems and must be relied upon to activate properly when needed, as
opposed to an energy-absorbing pad or upper torso restraint that is
passive, and always available. Therefore, the potential advantages must
be balanced against these and other potential disadvantages in order to
develop standards for this design feature.
The FAA has considered the installation of inflatable lapbelts to
have two primary safety concerns: First, that they perform properly
under foreseeable operating conditions, and second, that they do not
perform in a manner or at such times as would constitute a hazard to
the airplane or occupants. This latter point has the potential to be
the more rigorous of the requirements, owing to the active nature of
the system.
The inflatable lapbelt will rely on electronic sensors for
signaling and pyrotechnic charges for activation so that it is
available when needed. These same devices could be susceptible to
inadvertent activation, causing deployment in a potentially unsafe
manner. The consequences of such deployment, as well as failure to
deploy, must be considered in establishing the reliability of the
system. Boeing must substantiate that the effects of an inadvertent
deployment in flight are either not a hazard to the airplane, or that
such deployment is an extremely improbable occurrence (less than
10-9 per flight hour). The effect of an inadvertent
deployment on a passenger or crewmember that might be positioned close
to the inflatable lapbelt should also be considered. The person could
be either standing or sitting. A minimum reliability level will have to
be established for this case, depending upon the consequences, even if
the effect on the airplane is negligible.
The potential for an inadvertent deployment could be increased as a
result of conditions in service. The installation must take into
account wear and tear so that the likelihood of an inadvertent
deployment is not increased to an unacceptable level. In this context,
an appropriate inspection interval and self-test capability are
considered necessary. Other outside influences are lightning and high
intensity radiated fields (HIRF). Existing regulations regarding
lightning, Sec. 25.1316, and existing HIRF special conditions for the
767-300 series airplanes, Special Conditions No. 25-ANM-18, are
applicable. For the purposes of compliance with those conditions, if
inadvertent deployment could cause a hazard to the airplane, the
inflatable lapbelt is considered a critical system; if inadvertent
deployment could cause injuries to persons, the inflatable lapbelt
should be considered an essential system. Finally, the inflatable
lapbelt installation should be protected from the effects of fire, so
that an additional hazard is not created by, for example, a rupture of
the pyrotechnic squib.
In order to be an effective safety system, the inflatable lapbelt
must function properly and must not introduce any additional hazards to
occupants as a result of its functioning. There are several areas where
the inflatable lapbelt differs from traditional occupant protection
systems and requires special conditions to ensure adequate performance.
Because the inflatable lapbelt is essentially a single use device,
there is the potential that it could deploy under crash conditions that
are not sufficiently severe as to require head injury protection from
the inflatable lapbelt. Since an actual crash is frequently composed of
a series of impacts before the airplane comes to rest, this could
render the inflatable lapbelt useless if a larger impact follows the
initial impact. This situation does not exist with energy absorbing
pads or upper torso restraints, which tend to provide continuous
protection regardless of severity or number of impacts in a crash
event. Therefore, the inflatable lapbelt installation should be such
that the inflatable lapbelt will provide protection when it is
required, by not expending its protection during a less severe impact.
Also, it is possible to have several large impact events during the
course of a crash, but there will be no requirement for the inflatable
lapbelt to provide protection for multiple impacts.
Since each occupant's restraint system provides protection for that
occupant only, the installation must address seats that are unoccupied.
It will be necessary to show that the required protection is provided
for each occupant regardless of the number of occupied seats, and
considering that unoccupied seats may have lapbelts that are active.
The inflatable lap belt should be effective for a wide range of
occupants. The FAA has historically considered the range from the fifth
percentile female to the ninety-fifth percentile male as the range of
occupants that must be taken into account. In this case, the FAA is
proposing consideration of a broader range of occupants, due to the
nature of the lapbelt installation and its close proximity to the
occupant. In a similar vein, these persons could have assumed the brace
position for those accidents where an impact is anticipated. Test data
indicate that occupants in the brace position do not require
supplemental protection, and so it would not be necessary to show that
the inflatable lapbelt will enhance the brace position. However, the
inflatable lapbelt must not introduce a hazard in that case when
deploying into the seated, braced occupant.
Another area of concern is the use of seats, so equipped, by
children whether lap-held, in approved child safety seats, or occupying
the seat directly. Although specifically prohibited by the FAA
operating regulations, the use of the supplementary loop belt (``belly
belt'') may be required by other civil aviation authorities, and should
also be considered with the end goal of meeting those regulations.
Similarly, if the seat is occupied by a pregnant woman, the
installation needs to address such usage, either by demonstrating that
it will function properly, or by adding appropriate limitation on
usage.
Since the inflatable lapbelt will be electrically powered, there is
the possibility that the system could fail due to a separation in the
fuselage. Since this system is intended as crash/post-crash protection
means, failure due to fuselage separation is not acceptable. As with
emergency lighting, the system should function properly if such a
separation occurs at any point in the fuselage.
Since the inflatable lapbelt is likely to have a large volume
displacement, the inflated bag could potentially impede egress of
passengers. Since the bag deflates to absorb energy, it is likely that
an inflatable lapbelt would be deflated at the time that persons would
be trying to leave their seats. Nonetheless, it is considered
appropriate to specify a time
[[Page 1621]]
interval after which the inflatable lapbelt may not impede rapid
egress. Ten seconds has been chosen as a reasonable time since this
corresponds to the maximum time allowed for an exit to be openable
(Sec. 25.809). In actuality, it is unlikely that an exit would be
prepared by a flight attendant this quickly in an accident severe
enough to warrant deployment of the inflatable lapbelt, and the
inflatable lapbelt will likely deflate much quicker than ten seconds.
This potential impediment to rapid egress is even more critical at
the seats installed in the emergency exit rows. Section 25.813 requires
access to the exit from the main aisle in the form of an unobstructed
passageway and no interference in opening the exit. The restraint
system must not create an impediment to the access to, and the opening
of, the exit. In some cases, the passenger is the one who will open the
exit, such as a Type III over wing hatch. These lapbelts should be
evaluated in the exit row under existing regulations (Sec. Sec. 25.809
and 25.813) and guidance material. The inflatable lapbelts must also be
evaluated in post crash conditions and should be evaluated using
representative restraint systems in the bag-deployed condition. This
evaluation would include reviewing the access to and opening of the
exit, specifically for obstructions in the egress path and any
interferences in opening the exit. Each unique interior configuration
must be considered, for example, passageway width, single or dual
passageways with outboard seat removed, etc. If the restraint creates
any obstruction or interference, it is likely that it could impede the
rapid egress of the airplane. Project-specific guidance is likely
necessary if these restraint systems are installed at exit door rows.
The current special conditions for the Boeing 777 series airplanes,
Special Conditions No. 25-187A-SC, were amended to address flammability
of the airbag material. During the development of the inflatable
lapbelt, the manufacturer was unable to develop a fabric that would
meet the inflation requirements for the bag and the flammability
requirements of part I, paragraph (a)(1)(ii), of appendix F to part 25.
The fabrics that were developed that met the flammability requirement
did not produce acceptable deployment characteristics. However, the
manufacturer was able to develop a fabric that meets the less stringent
flammability requirements of part I, paragraph (a)(1)(iv), of appendix
F to part 25 and has acceptable deployment characteristics.
Part I of appendix F to part 25 specifies the flammability
requirements for interior materials and components. There is no
reference to inflatable restraint systems in appendix F, because such
devices did not exist at the time the flammability requirements were
written. The existing requirements are based on both material types, as
well as use, and have been specified in light of the state-of-the-art
of materials available to perform a given function. In the absence of a
specific reference, the default requirement would be for the type of
material used to construct the inflatable restraint, which is a fabric
in this case. However, in writing special conditions, the FAA must also
consider the use of the material, and whether the default requirement
is appropriate. In this case, the specialized function of the
inflatable restraint means that highly specialized materials are
needed. The standard normally applied to fabrics is a 12-second
vertical ignition test. However, materials that meet this standard do
not perform adequately as inflatable restraints. Since the safety
benefit of the inflatable restraint is very significant, the
flammability standard appropriate for these devices should not screen
out suitable materials, thereby effectively eliminating use of
inflatable restraints. The FAA will need to establish a balance between
the safety benefit of the inflatable restraint and its flammability
performance. At this time, the 2.5-inch per minute horizontal test is
considered to provide that balance. As the state-of-the-art in
materials progresses (which is expected), the FAA may change this
standard in subsequent special conditions to account for improved
materials.
The following special conditions can be characterized as addressing
either the safety performance of the system or the system's integrity
against inadvertent activation. Because a crash requiring use of the
inflatable lapbelts is a relatively rare event, and because the
consequences of an inadvertent activation are potentially quite severe,
these latter requirements are probably the more rigorous from a design
standpoint.
Finally, it should be noted that the special conditions are
applicable to the inflatable lapbelt system as installed. The special
conditions are not an installation approval. Therefore, while the
special conditions relate to each such system installed, the overall
installation approval is a separate finding and must consider the
combined effects of all such systems installed.
Applicability
As discussed above, these special conditions are applicable to the
767-300. 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, the special conditions would apply to that
model as well.
Conclusion
This action affects only certain novel or unusual design features
on one model of airplanes. It is not a rule of general applicability.
The substance of these special conditions has been subjected to the
notice and comment period in several prior instances and has been
derived without substantive change from those previously issued. It is
unlikely that prior public comment would result in a significant change
from the substance contained herein. Therefore, because a delay would
significantly affect the certification of the airplane, which is
imminent, the FAA has determined that prior public notice and comment
are unnecessary and impracticable, and good cause exists for adopting
these special conditions upon issuance. The FAA is requesting comments
to allow interested persons to submit views that may not have been
submitted in response to the prior opportunities for comment described
above.
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 767-300 airplanes.
1. Seats with Inflatable Lapbelts. It must be shown that the
inflatable lapbelt will deploy and provide protection under crash
conditions where it is necessary to prevent serious head injury. The
means of protection must take into consideration a range of stature
from a two-year-old child to a ninety-fifth percentile male. The
inflatable lapbelt must provide a consistent approach to energy
absorption throughout that range of occupants. In addition, the
following situations must be considered:
a. The seat occupant is holding an infant.
[[Page 1622]]
b. The seat occupant is a child in a child restraint device.
c. The seat occupant is a child not using a child restraint device.
d. The seat occupant is a pregnant woman.
2. The inflatable lapbelt must provide adequate protection for each
occupant regardless of the number of occupants of the seat assembly,
considering that unoccupied seats may have active seatbelts.
3. The design must prevent the inflatable lapbelt from being either
incorrectly buckled or incorrectly installed such that the inflatable
lapbelt would not properly deploy. Alternatively, it must be shown that
such deployment is not hazardous to the occupant and will provide the
required head injury protection.
4. It must be shown that the inflatable lapbelt system is not
susceptible to inadvertent deployment as a result of wear and tear or
inertial loads resulting from in-flight or ground maneuvers (including
gusts and hard landings) likely to be experienced in service.
5. Deployment of the inflatable lapbelt must not introduce injury
mechanisms to the seated occupant or result in injuries that could
impede rapid egress. This assessment should include an occupant who is
in the brace position when it deploys and an occupant whose belt is
loosely fastened.
6. It must be shown that inadvertent deployment of the inflatable
lapbelt, during the most critical part of the flight, will either not
cause a hazard to the airplane or its occupants, or meets the
requirements of Sec. 25.1309(b).
7. It must be shown that the inflatable lapbelt will not impede
rapid egress of occupants 10 seconds after its deployment.
8. The system must be protected from lightning and HIRF. The
threats specified in existing regulations regarding lightning, Sec.
25.1316, and existing HIRF special conditions for the Boeing Model 767
series aircraft, Special Conditions No. 25-ANM-18, are incorporated by
reference for the purpose of measuring lightning and HIRF protection.
For the purposes of complying with HIRF requirements, the inflatable
lapbelt system is considered a ``critical system'' if its deployment
could have a hazardous effect on the airplane; otherwise, it is
considered an ``essential'' system.
9. Inflatable lapbelts, once deployed, must not adversely affect
the emergency lighting system (i.e., block proximity lights to the
extent that the lights no longer meet their intended function).
10. The inflatable lapbelt must function properly after loss of
normal aircraft electrical power and after a transverse separation of
the fuselage at the most critical location. A separation at the
location of the lapbelt does not have to be considered.
11. It must be shown that the inflatable lapbelt will not release
hazardous quantities of gas or particulate matter into the cabin.
12. The inflatable lapbelt installation must be protected from the
effects of fire such that no hazard to occupants will result.
13. There must be a means for a crewmember to verify the integrity
of the inflatable lapbelt activation system prior to each flight, or it
must be demonstrated to operate reliably between inspection intervals.
The FAA considers the loss of the airbag system deployment function
alone (i.e., independent of the conditional event that requires the
airbag system deployment) to be a major failure condition.
14. The inflatable material may not have an average burn rate of
greater than 2.5 inches/minute when tested using the horizontal
flammability test as defined in 14 CFR part 25, appendix F, part I,
paragraph (b)(5).
Issued in Renton, Washington, on January 5, 2012.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service, ANM-100.
[FR Doc. 2012-350 Filed 1-10-12; 8:45 am]
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