[Federal Register Volume 83, Number 79 (Tuesday, April 24, 2018)]
[Rules and Regulations]
[Pages 17744-17746]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-08556]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2017-0637; Special Conditions No. 25-724-SC]


Special Conditions: Textron Aviation Inc. Model 700 Airplane; 
Occupant Protection for Side-Facing Seats Installed Forward of Aft-
Facing Seats

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final special conditions; request for comments.

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SUMMARY: These special conditions are issued for the Textron Aviation 
Inc. (Textron) Model 700 airplane. This airplane will have a novel or 
unusual design feature when compared to the state of technology 
envisioned in the airworthiness standards for transport-category 
airplanes. This design feature is side-facing seats installed forward 
of aft-facing seats. 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: This action is effective on Textron on April 24, 2018. Send your 
comments by June 8, 2018.

ADDRESSES: Send comments identified by docket number FAA-2017-0637 
using any of the following methods:
     Federal eRegulations Portal: Go to http://www.regulations.gov/and follow the online instructions for sending your 
comments electronically.
     Mail: Send comments to Docket Operations, M-30, U.S. 
Department of Transportation (DOT), 1200 New Jersey Avenue SE, Room 
W12-140, West Building Ground Floor, Washington, DC, 20590-0001.
     Hand Delivery or Courier: Take comments to Docket 
Operations in Room W12-140 of the West Building Ground Floor at 1200 
New Jersey Avenue SE, Washington, DC, between 9 a.m. and 5 p.m., Monday 
through Friday, except Federal holidays.
     Fax: Fax comments to Docket Operations at 202-493-2251.
    Privacy: The FAA will post all comments it receives, without 
change, to http://www.regulations.gov/, including any personal 
information the commenter provides. Using the search function of the 
docket website, anyone can find and read the electronic form of all 
comments received into any FAA docket, including the name of the 
individual sending the comment (or signing the comment for an 
association, business, labor union, etc.). DOT's complete Privacy Act 
Statement can be found in the Federal Register published on April 11, 
2000 (65 FR 19477-19478).
    Docket: Background documents or comments received may be read at 
http://www.regulations.gov/ at any time. Follow the online instructions 
for accessing the docket or go to Docket Operations in Room W12-140 of 
the West Building Ground Floor at 1200 New Jersey Avenue SE, 
Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Alan Sinclair, FAA, Airframe and Cabin 
Safety Section, AIR-675, Transport Standards Branch, Policy and 
Innovation Division, Aircraft Certification Service, 1601 Lind Avenue 
SW, Renton, Washington 98057-3356; telephone 425-227-2195; facsimile 
425-227-1320.

SUPPLEMENTARY INFORMATION: The substance of these special conditions 
has been published in the Federal Register for public comment in 
several prior instances with no substantive comments received. The FAA 
therefore finds it unnecessary to delay the effective date and finds 
that good cause exists for making these special conditions effective 
upon publication in the Federal Register.

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 November 20, 2014, Textron applied for a type certificate for 
their new Model 700 airplane. The Model 700 airplane is a turbofan-
powered executive-jet airplane with seating for two crewmembers and 12 
passengers. This airplane will have a maximum takeoff weight of 38,514 
pounds.

Type Certification Basis

    Under the provisions of title 14, Code of Federal Regulations (14 
CFR) 21.17, Textron must show that the Model 700 airplane meets the 
applicable provisions of 14 CFR part 25, as amended by

[[Page 17745]]

Amendments 25-1 through 25-139, 25-141, and 25-143.
    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 Textron Model 700 airplane because 
of a novel or unusual design feature, special conditions are prescribed 
under the provisions of Sec.  21.16.
    Special conditions are initially applicable to the model for which 
they are issued. Should the type certificate for that model be amended 
later to include any other model that incorporates the same novel or 
unusual design feature, these special conditions would also apply to 
the other model under Sec.  21.101.
    In addition to the applicable airworthiness regulations and special 
conditions, the Model 700 airplane must comply with the fuel-vent and 
exhaust-emission requirements of 14 CFR part 34, and the noise-
certification requirements of 14 CFR part 36.
    The FAA issues special conditions, as defined in 14 CFR 11.19, in 
accordance with Sec.  11.38, and they become part of the type 
certification basis under Sec.  21.17(a)(2).

Novel or Unusual Design Features

    The Textron Model 700 will incorporate the following novel or 
unusual design feature: Side-facing seats installed forward of aft-
facing seats.

Discussion

    Many of the Textron Model 700 interior configurations include a 
multiple-place side-facing seat installed just forward of an aft-facing 
seat. There is the possibility of interaction between the aft-facing 
seat and the occupant in the aft-most seating position on the multiple-
place side-facing seat. Textron is proposing to install a structural 
armrest aft of the multiple-place side-facing seat and forward of the 
aft-facing seat. See Figure 1.
[GRAPHIC] [TIFF OMITTED] TR24AP18.000

    Dynamic seat testing is required of all applicants who plan to 
install side-facing and oblique-angled seats in passenger airplanes. 
The intent of dynamic seat testing is to evaluate airplane seats, 
restraints, and related interior systems to demonstrate their 
structural strength and their ability to protect an occupant from 
serious injuries in a survivable crash. The current regulations in 
Sec. Sec.  25.561, 25.562, and 25.785 address occupant injury 
protection for forward and aft-facing seats.
    The FAA will issue special conditions separately to address the 
additional occupant-injury protection concerns raised for side-facing 
seats. However, the aft occupant of the side-facing seat (see Figure 1 
in these special conditions) may interact with the aft-facing seat, a 
scenario that the regulations do not specifically address.
    The aft-facing seat back could deform during the dynamic-test 
event, and could contact the occupant in the aft side-facing seat. The 
point that the seat back contacts the occupant could be in an area of 
the body that has no defined, acceptable, injury-evaluation method, 
such as the shoulder. This type of contact is addressed in these side-
facing-seat special conditions, which prohibit body-to-body contact.
    The applicant proposed installing a structural armrest between the 
side-facing seat and the aft-facing seat to help prevent contact 
between the aft-facing seat and the aft occupant of the side-facing 
seat. This contact would be likely to occur if the structural armrest 
failed to perform as intended in an emergency landing. Therefore, the 
purpose of these special conditions is to define the specific 
structural requirements of the proposed structural armrest, and the 
additional requirements necessary to protect the seated occupant from 
both the side-facing seat and the adjacent aft-facing seat.
    The applicant is likely to have to conduct two or more 16g forward 
structural tests with the combination of the side-facing seat, 
structural armrest, and aft-facing seat to account for all critical 
cases.
    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.

Applicability

    As discussed above, these special conditions are applicable to the 
Textron Model 700 airplane. Should Textron apply at a later date for a 
change to the type certificate to include another model incorporating 
the same novel or unusual design feature, these special conditions 
would apply to that model as well.

Conclusion

    This action affects only a certain novel or unusual design feature 
on one

[[Page 17746]]

model of airplane. It is not a rule of general applicability.

List of Subjects in 14 CFR Part 25

    Aircraft, Aviation safety, Reporting and recordkeeping 
requirements.

    The authority citation for these special conditions is as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, 44704.

The Special Conditions

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the following special conditions are issued as part of 
the type certification basis for Textron Model 700 airplanes with a 
structural armrest installed between a side-facing seat, located 
forward of aft-facing seats, and the aft-facing seats.
    1. The applicant must propose a certification strategy for the 
structural armrest. This strategy must address the structural integrity 
of the structural armrest and occupant protection after a survivable 
crash. The strategy must define how the applicant will ensure that the 
installation, when permanently deformed due to the application of 
static, dynamic, and interaction (with aft-facing seat) loads, and 
while complying with the applicable Sec. Sec.  25.561 and 25.562 
requirements, meets the following conditions:
    a. The proposed structural armrest must not contact the occupant in 
the aft-most seating position of the side-facing seat, such that the 
armrest imparts any load, other than incidental and non-injurious 
contact, with the seat occupant.
    b. The backrest of the aft-facing seat must not touch the occupant 
in the aft-most seating position of the side-facing seat.
    c. The proposed structural armrest must not impose loads to the 
side-facing seat structure, and;
    d. The seat back of the aft-facing seat must not, as a result of 
contact with the structural armrest, result in damage or permanent 
deformation of the seat back that could be injurious to the occupant of 
the aft-facing seat.
    2. In addition, the applicant must:
    a. Test, to the emergency-landing conditions listed in Sec.  
25.562, the structural armrest and the aft-facing seat together, as a 
system, with pitch and roll of the seat track to ensure that the 
armrest continues to protect the occupant of the side-facing seat.
    b. Conduct 16g forward structural tests with the combination of the 
side-facing seat, structural armrest, and the aft-facing seat, 
accounting for all critical cases. For these tests, the applicant 
should account for all structural requirements and post-test 
conditions. Anthropomorphic test dummies are required as part of Sec.  
25.562 structural testing.
    c. Apply to the seat track the worst-case floor deformation that:
    i. Produces the maximum load into the structural armrest for 
armrests that are integrally a part of any seat structure. This maximum 
load includes the load caused by the floor deformation and the load 
from the aft-facing seat back.
    ii. Allows the aft-facing seat back the most forward dynamic 
deformation in the area of the side-facing seat's aft occupant. No 
contact between the aft-facing seat and the side-facing seat aft 
occupant is acceptable.

    Issued in Renton, Washington, on April 17, 2018.
Paul Siegmund,
Acting Manager, Transport Standards Branch, Policy and Innovation 
Division, Aircraft Certification Service.
[FR Doc. 2018-08556 Filed 4-23-18; 8:45 am]
BILLING CODE 4910-13-P


