[Federal Register Volume 67, Number 169 (Friday, August 30, 2002)]
[Rules and Regulations]
[Pages 55703-55706]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-22119]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. NM226; Special Conditions No. 25-211-SC]


Special Conditions: Airbus Model A319, A320, and A321 Series 
Airplane; Seats With Inflatable Lapbelts

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final special conditions; request for comments.

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SUMMARY: These special conditions are issued for Airbus Model A319, 
A320, and A321 series airplanes. These airplanes, as modified by AMSAFE 
Aviation, 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 August 16, 
2002. Comments must be received on or before September 30, 2002.

ADDRESSES: Comments on this proposal may be mailed in duplicate to: 
Federal Aviation Administration (FAA), Transport Airplane Directorate, 
Attn: Rules Docket (ANM-113), Docket No. NM226, 1601 Lind Avenue SW., 
Renton, Washington, 98055-4056; or delivered in duplicate to the 
Transport Airplane Directorate at the above address. Comments must be 
marked: Docket No. NM226. Comments may be inspected in the Rules Docket 
weekdays, except Federal holidays, between 7:30 a.m. and 4 p.m.

FOR FURTHER INFORMATION CONTACT: Alan Sinclair, FAA, Airframe and Cabin 
Safety Branch, ANM-115, Transport Airplane Directorate, Aircraft 
Certification Service, 1601 Lind Avenue SW., Renton, Washington, 98055-
4056; telephone (425) 227-2195; facsimile (425) 227-1149.

SUPPLEMENTARY INFORMATION:

FAA's Determination as To Need for Public Process

    The FAA has determined that notice and opportunity for prior public 
comment are unnecessary in accordance with 14 CFR 11.38, because the 
FAA has provided previous opportunities to comment on substantially 
identical special conditions, and has fully considered and addressed 
all the substantive comments received. Based on a review of the comment 
history and the comment resolution, the FAA is satisfied that new 
comments are unlikely. The FAA, therefore, finds that good cause exists 
for making these special conditions effective upon issuance.

Comments Invited

    Although this action is in the form of final special conditions, 
and for the reasons stated above, is not preceded by notice and an 
opportunity for public comment, comments are invited on this rule. 
Interested persons are invited to participate in this rulemaking by 
submitting comments, data, or views. The most helpful comments 
reference a specific portion of the special conditions, explain the 
reason for any recommended change, and include supporting data. We ask 
that you send us two copies of written comments.
    We will file in the docket all comments we receive, as well as a 
report summarizing each substantive public contact with FAA personnel 
concerning these special conditions. The docket is available for public 
inspection before and after the comment closing date. If you wish to 
review the docket in person, go to the address in the ADDRESSES section 
of this preamble between 7:30 a.m. and 4 p.m., Monday through Friday, 
except Federal holidays.
    We will consider all comments we receive on or before the closing 
date for comments. We will consider comments filed late if it is 
possible to do so without incurring expense or delay. We may change 
these special conditions in light of the comments we receive.
    If you want the FAA to acknowledge receipt of your comments on this 
proposal, include with your comments a pre-addressed, stamped postcard 
on which the docket number appears. We will stamp the date on the 
postcard and mail it back to you.

Background

    On January 10, 2002, AMSAFE Aviation, P.O. Box 1570, Higley, 
Arizona 85236, applied for a supplemental type certificate to install 
AMSAFE Aviation Inflatable Restraints (AAIR) inflatable lapbelts for 
protection against head injury and head entrapment on certain seats in 
Airbus Model A319, A320, and A321 series airplanes. The certification 
of the Airbus Model A319, A320, and A321 series airplanes is currently 
scheduled for August 30, 2002. The Airbus Model A319, 320, and 321 
series airplanes are swept-wing, conventional tail, twin-engine, 
turbofan-powered transport airplanes. 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) 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, other rigid interior feature or, where that is 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 dynamic tests must be conducted for 
each seat type installed in the airplane. In particular, the 
regulations require that persons not suffer serious head injury under 
the conditions specified in the tests, and that a Head Injury Criteria 
(HIC) measurement of not more than 1000 units be recorded, should 
contact with the cabin interior occur. While the test conditions 
described in this section of the regulations are specific, it is the 
intent of the requirement that an adequate level of head injury 
protection be provided for crash severity up to and including that 
specified.
    It should be noted that while Amendment 25-64 is not part of the 
Airbus Model A319, A320, and A321 certification basis, Airbus 
voluntarily elected to comply with portions of 14 CFR 25.562, Amendment 
25-64, for the A319 and A321 airplanes, with the exception of 
Sec. 25.562(c)(5) and (c)(6) that contain the requirements for femur 
injury and HIC. Therefore, the seat installations with inflatable 
lapbelts are required to meet the requirements of Sec. 25.562 except 
for Sec. 25.562(c)(5) and (c)(6).

[[Page 55704]]

    Because Secs. 25.562 and 25.785 and associated guidance do not 
adequately address seats with inflatable lapbelts, the FAA recognizes 
that appropriate pass/fail criteria that do fully address the safety 
concerns specific to occupants of these seats need to be developed.
    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 statures. 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 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 this and other potential disadvantages in order to develop 
standards that will provide an equivalent level of safety to that 
intended by the regulations.
    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 its occupants. This latter point has the potential to 
be the more rigorous of the requirements, owing to the active nature of 
the system. With this philosophy in mind, the FAA has considered the 
following as a basis for the special conditions.
    The inflatable lapbelt will rely on electronic sensors for 
signaling and pyrotechnic charges, which then activate the lapbelt when 
needed. These same devices could be susceptible to inadvertent 
activation, causing deployment in a potentially unsafe manner. The 
consequences of such deployment must be considered in establishing the 
reliability of the system. AMSAFE 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 ``wear and 
tear'' into account 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 
electromagnetic fields (HIRF). Since the sensors that trigger 
deployment are electronic, they must be protected from the effects of 
these threats. Existing Special Conditions No. 25-ANM-23 regarding 
lightning and HIRF are therefore applicable. For the purposes of 
compliance with those special 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 protection 
according to the severity of the impact. Therefore, the inflatable 
lapbelt installation should be such that the inflatable lapbelt will 
provide protection when it is required, and will not expend its 
protection when it is not needed. These special conditions contain no 
requirement for the inflatable lapbelt to provide protection from 
multiple impacts, where more than one impact would require protection.
    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.
    Since a wide range of occupants could occupy a seat, the inflatable 
lapbelt 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 by deploying into the seated, 
braced occupant.
    Another area of concern is the use of inflatable lapbelts in seats 
occupied by children, who could be lap-held, in approved child safety 
seats, or occupying the seat directly. 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. A separation that 
occurs at the location of the inflatable lapbelt would not have to be 
considered.
    Since the inflatable lapbelt is likely to have a large volume 
displacement, the inflated bag could potentially impede egress of 
passengers. The bag deflates to absorb energy, so 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 interval after which the inflatable

[[Page 55705]]

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. In actuality, it is unlikely that an exit would 
be prepared this quickly in an accident severe enough to warrant 
deployment of the inflatable lapbelt, and the inflatable lapbelt will 
likely deflate in much less than ten seconds.
    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.

Type Certification Basis

    Under the provisions of Sec. 21.101, Amendment 21-69, effective 
September 16, 1991, AMSAFE Aviation must show that the Airbus Model 
A319, A320, and A321, as changed, continue to meet the applicable 
provisions of the regulations incorporated by reference in Type 
Certificate No. A28NM or the applicable regulations in effect on the 
date of application for the change. Subsequent changes have been made 
to Sec. 21.101 as part of Amendment 21-77, but those changes do not 
become effective until June 10, 2003. 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. A28NM are as follows:
    Amendments 25-1 through 25-56 for Airbus Model A319, A320, and A321 
series airplanes. The U.S. type certification basis for Airbus Model 
A319, A320, and A321 is established in accordance with Sec. 21.29 and 
Sec. 21.17 and the type certification application date. The U.S. type 
certification basis is listed in Type Certificate Data Sheet No. A28NM.
    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 Airbus Model A319, A320, and A321 
series airplanes because of a novel or unusual design feature, special 
conditions are prescribed under the provisions of Sec. 21.16.
    In addition to the applicable airworthiness regulations and special 
conditions, Airbus Model A319, A320, and A321 series airplanes must 
comply with the fuel vent and exhaust emission requirements of 14 CFR 
part 34 and the noise certification requirements of 14 CFR part 36.
    Special conditions, as defined in Sec. 11.19, are issued in 
accordance with Sec. 11.38 and become part of the type certification 
basis in accordance with Sec. 21.101(b)(2), Amendment 21-69, effective 
September 16, 1991.
    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, 
the special conditions would also apply to the other model under the 
provisions of Sec. 21.101(a)(1), Amendment 21-69, effective September 
16, 1991.

Novel or Unusual Design Features

    AMSAFE Aviation will install an inflatable lapbelt on certain seats 
of Airbus Model A319, A320, A321 series airplanes, in order to reduce 
the potential for head injury and head entrapment in the event of an 
accident. The inflatable lapbelt works similarly to an automotive 
airbag, except that the airbag is integrated with the lap belt of the 
restraint system. The inflatable lapbelts are considered a novel or 
unusual design feature.
    Federal regulations state the performance criteria for head injury 
and head entrapment 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 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 adopted for the Airbus 
Model A319, A320, and A321 series airplanes equipped with inflatable 
lapbelts. Other special 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 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 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 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.

Prior Comment

    One comment was received in response to the most recent publication 
of inflatable lapbelt special conditions (65 FR 60343), which are 
substantially identical to the special condition contained herein. The 
disposition of this comment is contained in Rules Docket No. NM176 and 
is available for examination by interested parties. In our disposition, 
we agreed with the commenter, but noted that the substance of the 
comment has already been addressed in showing compliance with existing 
regulations during the certification process. Therefore, this comment 
did not result in a change to the special conditions.

Applicability

    As discussed above, these special conditions are applicable to the 
Airbus Model A319, A320, and A321 series airplanes modified by AMSAFE 
Aviation. Should AMSAFE Aviation apply at a later date for a 
supplemental type certificate to modify any other model included on 
Type Certificate No. A28NM to incorporate the same novel or unusual 
design feature, these special conditions would apply to that model as 
well under the provisions of Sec. 21.101(a)(1).

Conclusion

    This action affects only certain novel or unusual design features 
on Airbus Model A319, A320, and A321 series airplanes. It is not a rule 
of general applicability, and it affects only the applicant who applied 
to the FAA for approval of these features on the airplane.

[[Page 55706]]

    The FAA has determined that notice and opportunity for prior public 
comment are unnecessary in accordance with 14 CFR 11.38, because the 
FAA has provided previous opportunities to comment on substantially 
identical special conditions, and has fully considered and addressed 
all the substantive comments received. Based on a review of the comment 
history and the comment resolution the FAA is satisfied that new 
comments are unlikely. The FAA, therefore, finds that good cause exists 
for making these special conditions effective upon issuance.

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, the Federal Aviation Administration (FAA) issues the 
following special conditions as part of the type certification basis 
for Airbus Model A319, A320, and A321 series airplanes modified by 
AMSAFE Aviation.

Seats With Inflatable Lapbelts

    1. 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 or head entrapment. 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. In addition, the following situations must be considered:
    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 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 consideration of 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 an inadvertent deployment, that could 
cause injury to a standing or sitting person, is improbable.
    7. 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 is extremely improbable.
    8. It must be shown that the inflatable lapbelt will not impede 
rapid egress of occupants 10 seconds after its deployment.
    9. The system must be protected from lightning and HIRF. The 
threats specified in Special Condition No. 25-ANM-23 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.
    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 reliably operate between inspection intervals.

    Issued in Renton, Washington, on August 16, 2002.
Ali Bahrami,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 02-22119 Filed 8-29-02; 8:45 am]
BILLING CODE 4910-13-P