[Federal Register Volume 88, Number 38 (Monday, February 27, 2023)]
[Rules and Regulations]
[Pages 12134-12136]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-03981]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2022-0126; Special Conditions No. 25-809-SC]


Special Conditions: Dassault Aviation Model Falcon 6X Airplane; 
Operation Without Normal Electrical Power

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final special conditions; request for comments.

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SUMMARY: These special conditions are issued for the Dassault Aviation 
(Dassault) Model Falcon 6X 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 an electronic flight-control system 
installation that establishes the criticality of the electrical power 
generation and distribution systems, such that the loss of all 
electrical power may be catastrophic to the airplane. 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 Dassault on February 27, 2023. Send 
comments on or before April 13, 2023.

ADDRESSES: Send comments identified by Docket No. FAA-2022-0126 using 
any of the following methods:
     Federal eRegulations Portal: Go to https://www.regulations.gov/ and follow the online instructions for sending 
your comments electronically.
     Mail: Send comments to Docket Operations, M-30, U.S. 
Department of Transportation (DOT), 1200 New Jersey Avenue SE, Room 
W12-140, West Building Ground Floor, Washington, DC 20590-0001.
     Hand Delivery or Courier: Take comments to Docket 
Operations in Room W12-140 of the West Building Ground Floor at 1200 
New Jersey Avenue SE, Washington, DC, between 9 a.m. and 5 p.m., Monday 
through Friday, except Federal holidays.
     Fax: Fax comments to Docket Operations at 202-493-2251.
    Privacy: Except for Confidential Business Information (CBI) as 
described in the following paragraph, and other

[[Page 12135]]

information as described in title 14, Code of Federal Regulations (14 
CFR) 11.35, the FAA will post all comments received without change to 
https://www.regulations.gov/, including any personal information you 
provide. The FAA will also post a report summarizing each substantive 
verbal contact received about these special conditions.
    Confidential Business Information: Confidential Business 
Information (CBI) is commercial or financial information that is both 
customarily and actually treated as private by its owner. Under the 
Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from 
public disclosure. If your comments responsive to these special 
conditions contain commercial or financial information that is 
customarily treated as private, that you actually treat as private, and 
that is relevant or responsive to these special conditions, it is 
important that you clearly designate the submitted comments as CBI. 
Please mark each page of your submission containing CBI as ``PROPIN.'' 
The FAA will treat such marked submissions as confidential under the 
FOIA, and the indicated comments will not be placed in the public 
docket of these special conditions. Send submissions containing CBI to 
the Information Contact below. Comments the FAA receives, which are not 
specifically designated as CBI, will be placed in the public docket for 
these special conditions.
    Docket: Background documents or comments received may be read at 
https://www.regulations.gov/ at any time. Follow the online 
instructions for accessing the docket or go to Docket Operations in 
Room W12-140 of the West Building Ground Floor at 1200 New Jersey 
Avenue SE, Washington, DC, between 9 a.m. and 5 p.m., Monday through 
Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Dan Poblete, Aircraft Systems, AIR-
623, Technical Innovation Policy Branch, Policy and Innovation 
Division, Aircraft Certification Service, Federal Aviation 
Administration, 3960 Paramount Boulevard, Suite 100, Lakewood, 
California 90712; telephone 562-627-5335, fax 562-627-5210; 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 finds that, pursuant to Sec.  11.38(b), new comments 
are unlikely, and notice and comment prior to this publication are 
unnecessary.

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 July 1, 2012, Dassault Aviation applied for a type certificate 
for its new Model Falcon 5X airplane. However, Dassault has decided not 
to release an airplane under the model designation Falcon 5X, instead 
choosing to change that model designation to Falcon 6X.
    In February of 2018, due to engine supplier issues, Dassault 
extended the type certificate application date for its Model Falcon 5X 
airplane under new Model Falcon 6X. This airplane is a twin-engine 
business jet with seating for 19 passengers, and has a maximum takeoff 
weight of 77,460 pounds.

Type Certification Basis

    Under the provisions of 14 CFR 21.17, Dassault must show that the 
Model Falcon 6X airplane meets the applicable provisions of part 25, as 
amended by amendments 25-1 through 25-146.
    If the Administrator finds that the applicable airworthiness 
regulations (e.g., 14 CFR part 25) do not contain adequate or 
appropriate safety standards for the Dassault Model Falcon 6X 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 Dassault Model Falcon 6X 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 Dassault Model Falcon 6X airplane will incorporate the 
following novel or unusual design features:
    An electronic flight-control system installation that establishes 
the criticality of the electrical power generation and distribution 
systems, such that the loss of all electrical power may be catastrophic 
to the airplane.

Discussion

    The Dassault Aviation Model Falcon 6X airplane will have a fly-by-
wire control system that requires a continuous source of electrical 
power to maintain an operable flight-control system. Section 
25.1351(d), ``Operation without normal electrical power,'' requires 
safe operation for at least five minutes, in visual flight rules (VFR), 
with normal power inoperative. This rule was structured around a 
traditional design, with mechanical control cables for flight control, 
while flightcrew considered the electrical failures, attempted to start 
engines(s) if necessary, and attempted to re-establish some of the 
electrical-power-generation capability.
    Changes in technology have produced advanced electrical and 
electronic airplane systems that requires a continuous source of 
electrical power to maintain an operable flight-control system. The 
Dassault Model Falcon 6X airplane design must not be time-limited in 
its operation, including being without the normal source of electrical 
power generated from engine generators or auxiliary power unit (APU), 
to maintain the same level of safety associated with traditional 
designs.
    Airplane service experience has shown that the loss of all 
electrical power, as generated by the airplane's engine generators or 
APU, is not extremely improbable. Therefore, the applicant must 
demonstrate that the airplane maintains safe flight and landing, 
including steering and braking on the ground with the use of airplane 
emergency electrical-power systems. These emergency electrical-power 
systems must be able to provide power to loads required for continued 
safe flight and landing.
    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.

[[Page 12136]]

Applicability

    As discussed above, these special conditions are applicable to the 
Dassault Model Falcon 6X airplane. Should Dassault 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 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.

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

    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 Dassault Aviation Model Falcon 6X 
airplanes.
    In lieu of the requirements of 14 CFR 25.1351(d), the following 
special conditions apply:
    (a) The applicant must show, by test or a combination of test and 
analysis, that the airplane is capable of continued safe flight and 
landing with all normal electrical power sources inoperative, as 
prescribed by paragraphs (b)(1) and (b)(2) below. For purposes of this 
special condition, normal sources of electrical-power generation do not 
include alternate power sources such as a battery, ram-air turbine, or 
independent power systems such as a flight-control permanent-magnet 
generating system.
    (b) The airplane is demonstrated to be capable of continued safe 
flight and landing by ensuring the performance of the systems 
capability, effects on crew workload and operating conditions, and the 
physiological needs of the flightcrew and passengers meet the 
requirements for the longest diversion time for which approval is 
sought.
    (1) Common-cause failures, cascading failures, and zonal physical 
threats must be considered in showing compliance with this requirement.
    (2) The ability to restore operation of portions of the electrical-
power generation and distribution system may be considered if it can be 
shown that unrecoverable loss of those portions of the system is 
extremely improbable. An alternative source of electrical power must be 
provided for the time required to restore the minimum electrical-power-
generation capability required for safe flight and landing. 
Unrecoverable loss of all engines may be excluded when showing that 
unrecoverable loss of critical portions of the electrical system is 
extremely improbable. Unrecoverable loss of all engines is covered in 
special condition (c), below, and thus may be excluded when showing 
compliance with this requirement.
    (c) Regardless of any electrical-generation and distribution-system 
recovery capability shown under special condition (a), above, 
sufficient electrical-system capability must be provided to:
    (1) Allow time to descend, with all engines inoperative, at the 
speed that provides the best glide distance, from the maximum operating 
altitude to the altitude at the top of the engine restart envelope, and
    (2) Subsequently allow multiple start attempts of the engines and 
APU. This capability must be provided in addition to the electrical 
capability required by existing part 25 requirements related to 
operation with all engines inoperative.
    (d) The airplane emergency electrical-power system must be designed 
to supply electrical power required for:
    (1) Immediate safety, which must continue to operate without the 
need for flightcrew action following the loss of the normal electrical 
power, for a duration sufficient to allow reconfiguration to provide a 
non-time-limited source of electrical power.
    (2) Continued safe flight and landing for the maximum diversion 
time.
    (e) If APU-generated electrical power is used in satisfying the 
requirements of these special conditions, and if reaching a suitable 
runway upon which to land is beyond the capacity of the battery 
systems, then the APU must be able to be started under any foreseeable 
flight condition prior to the depletion of the battery or the 
restoration of normal electrical power, which ever occurs first. Flight 
tests must demonstrate this capability at the most critical condition.
    (1) The applicant must show that the APU will provide adequate 
electrical power for continued safe flight and landing.
    (2) The Airplane Flight Manual (AFM) must incorporate non-normal 
procedures that direct the pilot to take appropriate actions to 
activate the APU after loss of normal engine-generated electrical 
power.
    (f) As a part of showing compliance with these special conditions, 
the tests by which loss of all normal electrical power is demonstrated 
must also take into account the following:
    (1) The failure condition should be assumed to occur during night 
instrument meteorological conditions (IMC), at the most critical phase 
of the flight, relative to the worst possible electrical-power 
distribution and equipment-loads-demand condition.
    (2) After the un-restorable loss of normal engine-generated 
electrical power, the airplane-engine-restart capability must be 
provided and operations continued in IMC.
    (3) The applicant must demonstrate that the aircraft is capable of 
continued safe flight and landing. The length of time must be computed 
based on the maximum diversion-time capability for which the airplane 
is being certified. Consideration for airspeed reductions resulting 
from the associated failure or failures must be made.
    (4) The airplane must provide adequate indication of loss of normal 
electrical power to direct the pilot to the non-normal procedures, and 
the AFM must incorporate non-normal procedures that will direct the 
pilot to take appropriate actions.

    Issued in Kansas City, Missouri, on February 22, 2023.
Patrick R. Mullen,
Manager, Technical Innovation Policy Branch, Policy and Innovation 
Division, Aircraft Certification Service.
[FR Doc. 2023-03981 Filed 2-24-23; 8:45 am]
BILLING CODE 4910-13-P


