[Federal Register Volume 85, Number 138 (Friday, July 17, 2020)]
[Rules and Regulations]
[Pages 43422-43423]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-14992]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2020-0285; Special Conditions No. 25-771-SC]


Special Conditions: Avidyne Corporation, Textron Aviation Inc. 
Model 550, 560, and 560XL Airplanes; Electronic-System Security 
Protection From Unauthorized External Access

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final special conditions; request for comments.

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SUMMARY: These special conditions are issued for Textron Aviation Inc. 
(Textron) Model 550, 560, and 560XL airplanes. These airplanes, as 
modified by Avidyne Corporation, 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 Avidyne Corporation avionics that allow external connection 
to previously isolated data networks, which are connected to systems 
that perform functions required for the safe operation of the airplane. 
This feature creates a potential for unauthorized persons to access the 
aircraft-control domain and airline information-services domain, and 
presents security vulnerabilities related to the introduction of 
computer viruses and worms, user errors, and intentional sabotage of 
airplane electronic assets (networks, systems, and databases). 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 Avidyne Corporation on July 17, 
2020. Send comments on or before August 31, 2020.

ADDRESSES: Send comments identified by Docket No. FAA-2020-0285 using 
any of the following methods:
     Federal eRegulations Portal: Go to http://www.regulations.gov/ 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: Varun Khanna, Airplane and Flightcrew 
Interface Section, AIR-671, Transport Standards Branch, Policy and 
Innovation Division, Aircraft Certification Service, Federal Aviation 
Administration, 2200 South 216th Street, Des Moines, Washington 98198; 
telephone and fax 206-231-3159; email [email protected].

SUPPLEMENTARY INFORMATION: The substance of these special conditions 
has been published in the Federal Register for public comment in 
several prior instances with no substantive comments received. 
Therefore, the FAA has determined that prior public notice and comment 
are unnecessary, and finds that, for the same reason, good cause exists 
for adopting these special conditions upon publication in the Federal 
Register.

Comments Invited

    The FAA invites interested people to take part in this rulemaking 
by sending written comments, data, or views. The most helpful comments 
reference a specific portion of the special conditions, explain the 
reason for any recommended change, and include supporting data.
    The FAA will consider all comments received by the closing date for 
comments. The FAA may change these special conditions based on the 
comments received.

Background

    On February 1, 2019, Avidyne Corporation applied for a supplemental 
type certificate for Avidyne Corporation avionics connected to the 
aircraft-control domain and airline information-services domain in 
Textron Model 550, 560, and 560XL airplanes.
    The Model 550 is a twin-engine, transport-category airplane with a 
maximum takeoff weight of 14,800 pounds, and seating for up to 11 
passengers, depending upon configuration.
    The Model 560 is a twin-engine, transport-category airplane with a 
maximum takeoff weight of 16,630 pounds, and seating for up to 11 
passengers, depending upon configuration.
    The Model 560XL is a twin-engine, transport-category airplane with 
a maximum takeoff weight of 20,200 pounds, and seating for up to 12 
passengers, depending upon configuration.

Type Certification Basis

    Under the provisions of title 14, Code of Federal Regulations (14 
CFR) 21.101, Avidyne Corporation must show that the Textron Model 550, 
560, and 560XL airplanes, as changed, continue to meet the applicable 
provisions of the regulations listed in Type Certificate No. A22CE or 
the applicable regulations in effect on the date of application for the 
change, except for earlier amendments as agreed upon by the FAA.
    If the Administrator finds that the applicable airworthiness 
regulations (i.e., 14 CFR part 25) do not contain adequate or 
appropriate safety standards for Textron Model 550, 560, and 560XL 
airplanes because of a novel or unusual design feature, special 
conditions are prescribed under the provisions of Sec.  21.16.

[[Page 43423]]

    Special conditions are initially applicable to the model for which 
they are issued. Should the applicant apply for a supplemental type 
certificate to modify any other model included on the same type 
certificate to incorporate the same novel or unusual design feature, 
these special conditions would also apply to the other model under 
Sec.  21.101.
    In addition to the applicable airworthiness regulations and special 
conditions, Textron Model 550, 560, and 560XL airplanes must comply 
with the fuel-vent and exhaust-emission requirements of 14 CFR part 34, 
and the noise-certification requirements of 14 CFR part 36.
    The FAA issues special conditions, as defined in 14 CFR 11.19, in 
accordance with Sec.  11.38, and they become part of the type 
certification basis under Sec.  21.101.

Novel or Unusual Design Features

    The Textron Model 550, 560, and 560XL airplanes, as modified by 
Avidyne Corporation, will incorporate the following novel or unusual 
design features:
    Avidyne Corporation avionics that allow external connection to 
previously isolated data networks, which are connected to systems that 
perform functions required for the safe operation of the airplane.

Discussion

    The Textron Model 550, 560, and 560XL airplanes' architecture and 
network configuration is novel or unusual for commercial transport 
airplanes because it may allow increased connectivity to and access 
from external network sources and airline operations and maintenance 
networks to the airplane control domain and airline information 
services domain. The airplane control domain and airline information-
services domain perform functions required for the safe operation and 
maintenance of the airplane. Previously, these domains had very limited 
connectivity with external network sources. This data network and 
design integration creates a potential for unauthorized persons to 
access the aircraft-control domain and airline information-services 
domain, and presents security vulnerabilities related to the 
introduction of computer viruses and worms, user errors, and 
intentional sabotage of airplane electronic assets (networks, systems, 
and databases) critical to the safety and maintenance of the airplane.
    The existing regulations and guidance material did not anticipate 
these types of airplane system architectures. Furthermore, 14 CFR 
regulations and the current system safety assessment policy and 
techniques do not address potential security vulnerabilities, which 
could be exploited by unauthorized access to airplane networks, data 
buses, and servers. Therefore, these special conditions ensure that the 
security (i.e., confidentiality, integrity, and availability) of 
airplane systems is not compromised by unauthorized wired or wireless 
electronic connections.
    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 
Textron Model 550, 560, and 560XL airplanes. Should Avidyne Corporation 
apply at a later date for a supplemental type certificate to modify any 
other model included on Type Certificate No. A22CE to incorporate the 
same novel or unusual design feature, these special conditions would 
apply to that model as well.

Conclusion

    This action affects only certain novel or unusual design features 
on one model of airplane. It is not a rule of general applicability and 
affects only the applicant who applied to the FAA for approval of the 
features on the airplane.

List of Subjects in 14 CFR Part 25

    Aircraft, Aviation safety, Reporting and recordkeeping 
requirements.

Authority Citation

    The authority citation for these special conditions is as follows:

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

The Special Conditions

    [ssquf] 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 550, 560, and 560XL 
airplanes, as modified by Avidyne Corporation, for airplane electronic-
system security protection from unauthorized external access.
    1. The applicant must ensure airplane electronic-system security 
protection from access by unauthorized sources external to the 
airplane, including those possibly caused by maintenance activity.
    2. The applicant must ensure that electronic-system security 
threats are identified and assessed, and that effective electronic-
system security protection strategies are implemented to protect the 
airplane from all adverse impacts on safety, functionality, and 
continued airworthiness.
    3. The applicant must establish appropriate procedures to allow the 
operator to ensure that continued airworthiness of the airplane is 
maintained, including all post-type-certification modifications that 
may have an impact on the approved electronic-system security 
safeguards.

    Issued in Des Moines, Washington, on July 7, 2020.
James E. Wilborn,
Acting Manager, Transport Standards Branch, Policy and Innovation 
Division, Aircraft Certification Service.

[FR Doc. 2020-14992 Filed 7-16-20; 8:45 am]
BILLING CODE 4910-13-P