Document ID: FAA-2017-0319-0001
Agency: faa
Document Type: Rule
Title: Special Conditions: Embraer S.A., Model ERJ 190-300 Series Airplanes; Operation without Normal Electrical Power
Posted Date: 2017-05-10T04:00Z

[Federal Register Volume 82, Number 89 (Wednesday, May 10, 2017)]
[Rules and Regulations]
[Pages 21679-21681]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-09441]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2017-0319; Special Conditions No. 25-668-SC]

Special Conditions: Embraer S.A., Model ERJ 190-300 Series 
Airplanes; Operation Without Normal Electrical Power

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 Embraer S.A. 
(Embraer) Model ERJ 190-300 series airplanes. These airplanes will have 
novel or unusual design features when compared to the state of 
technology envisioned in the airworthiness standards for transport 
category airplanes. These design features are electrical and electronic 
systems that perform critical functions, the loss of which could be 
catastrophic to the airplane. The applicable airworthiness regulations 
do not contain adequate or appropriate safety standards for these 
design features. 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 Embraer S.A. on May 10, 2017. We 
must receive your comments by June 26, 2017.

ADDRESSES: Send comments identified by docket number FAA-2017-0319 
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 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).
    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 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: Stephen Slotte, FAA, Airplane and 
Flight Crew Interface Branch, ANM-111, Transport Airplane Directorate, 
Aircraft Certification Service, 1601 Lind Avenue SW., Renton, 
Washington 98057-3356; telephone 425-227-2315; facsimile 425-227-1320.

SUPPLEMENTARY INFORMATION: The FAA has determined that notice of, and 
opportunity for prior public comment on, these special conditions is 
impracticable because these procedures would significantly delay 
issuance of the design approval and thus delivery of the affected 
airplanes.
    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 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 September 13, 2013, Embraer applied for an amendment to type 
certificate (TC) no. A57NM to include

[[Page 21680]]

the new Model ERJ 190-300 airplane. This airplane, which is a 
derivative of the ERJ 190-100 STD currently approved under TC no. 
A57NM, is a 94- to 114-passenger transport category airplane with two 
Pratt & Whitney Model PW1900G engines and a new wing design with a high 
aspect ratio and raked wingtip.

Type Certification Basis

    Under the provisions of Title 14, Code of Federal Regulations (14 
CFR) 21.101, Embraer must show that the Model ERJ 190-300 airplane 
meets the applicable provisions of the regulations listed in type 
certificate no. A57NM or the applicable regulations in effect on the 
date of application for the change, except for earlier amendments as 
agreed upon by the FAA. Embraer must show that the Model ERJ 190-300 
airplane meets the applicable provisions of 14 CFR part 25, as amended 
by Amendments 25-1 through 25-137.
    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 Model ERJ 190-300 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 
design features, or should any other model already included on the same 
type certificate be modified 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, the Model ERJ 190-300 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.  21.101.

Novel or Unusual Design Features

    The Model ERJ 190-300 airplane will incorporate the following novel 
or unusual design features: Electrical and electronic systems that 
perform critical functions, the loss of which may result in loss of 
flight controls and other critical systems and may be catastrophic to 
the airplane.

Discussion

    The Model ERJ 190-300 airplane has a fly-by-wire flight control 
system that requires a continuous source of electrical power in order 
to maintain an operable flight control system. Section 25.1351(d), 
Operation without normal electrical power, requires safe operation in 
visual flight rule (VFR) conditions for at least five minutes after 
loss of normal electrical power excluding the battery. This rule was 
structured around a traditional design using mechanical control cables 
and linkages for flight control. These manual controls allowed the crew 
to maintain aerodynamic control of the airplane for an indefinite 
period of time after loss of all electrical power. Under these 
conditions, a mechanical flight control system provided the crew with 
the ability to fly the airplane while attempting to identify the cause 
of the electrical failure, restart engine(s) if necessary, and attempt 
to re-establish some of the electrical power generation capability.
    A critical assumption in Sec.  25.1351(d) is that the airplane is 
in VFR conditions at the time of the failure. This is not a valid 
assumption in today's airline operating environment where airplanes fly 
much of the time in instrument meteorological conditions on air traffic 
control defined flight paths. Another assumption in the existing rule 
is that the loss of all normal electrical power is the result of the 
loss of all engines. The five-minute period in the rule is to allow at 
least one engine to be restarted following an all-engine power loss in 
order to continue the flight to a safe landing. However, service 
experience on airplane models with similar electrical power system 
architecture as the airplane has shown that at least the temporary loss 
of all electrical power for causes other than all-engine failure is not 
extremely improbable.
    To maintain the same level of safety envisioned by the existing 
rule with traditional mechanical flight controls, the Model ERJ 190-300 
airplane design must not be time-limited in its operation under all 
reasonably foreseeable conditions, including loss of all normal sources 
of engine or auxiliary power unit (APU)-generated electrical power. 
Unless Embraer can show that the non-restorable loss of the engine and 
APU power sources is extremely improbable, Embraer must demonstrate 
that the airplanes can maintain safe flight and landing (including 
steering and braking on the ground for airplanes using steer/brake-by-
wire and/or fly-by-wire speed brake panels) with the use of its 
emergency/alternate electrical power systems. These electrical power 
systems, or the minimum restorable electrical power sources, must be 
able to power loads that are essential for continued safe flight and 
landing, including those required for the maximum length of approved 
flight diversion.

Applicability

    As discussed above, these special conditions are applicable to the 
Model ERJ 190-300 airplanes. Should Embraer 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 series 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, the FAA has 
determined that prior public notice and comment are unnecessary and 
impracticable, and good cause exists for adopting these special 
conditions upon publication in the Federal Register. 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 Embraer Model ERJ 190-300 airplanes.
    In lieu of 14 CFR 25.1351(d) the following special conditions 
apply:
    1. 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

[[Page 21681]]

electrical power sources inoperative, as prescribed by paragraphs 1.a. 
and 1.b., below. For purposes of these special conditions, normal 
sources of electrical power generation do not include any alternate 
power sources such as the battery, ram air turbine, or independent 
power systems such as the flight control permanent magnet generating 
system. In showing capability for continued safe flight and landing, 
the applicant must account for systems capability, effects on crew 
workload and operating conditions, and the physiological needs of the 
flightcrew and passengers for the longest diversion time for which the 
applicant is seeking approval.
    a. In showing compliance with this requirement, the applicant must 
account for common-cause failures, cascading failures, and zonal 
physical threats.
    b. The applicant may consider the ability to restore operation of 
portions of the electrical power generation and distribution system if 
it can be shown that unrecoverable loss of those portions of the system 
is extremely improbable. The design must provide an alternative source 
of electrical power for the time required to restore the minimum 
electrical power generation capability required for safe flight and 
landing. The applicant may exclude unrecoverable loss of all engines 
when showing compliance with this requirement.
    2. Regardless of any electrical generation and distribution system 
recovery capability shown under paragraph 1 of these special 
conditions, sufficient electrical system capability must be provided 
to:
    a. Allow time to descend, with all engines inoperative, at the 
speed that provides the best glide distance, from the maximum operating 
altitude to the top of the engine restart envelope, and
    b. Subsequently allow multiple start attempts of the engines and 
auxiliary power unit (APU). The design must provide this capability in 
addition to the electrical capability required by existing part 25 
requirements related to operation with all engines inoperative.
    3. The airplane emergency electrical power system must be designed 
to supply:
    a. Electrical power required for immediate safety, which must 
continue to operate without the need for crew 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.
    b. Electrical power required for continued safe flight and landing 
for the maximum diversion time.
    4. If the applicant uses APU-generated electrical power to satisfy 
the requirements of these special conditions, and if reaching a 
suitable runway for landing 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, whichever occurs first. Flight 
test must demonstrate this capability at the most critical condition.
    a. The applicant must show that the APU will provide adequate 
electrical power for continued safe flight and landing.
    b. The operating limitations section of 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-driven generated electrical power.
    5. As part of showing compliance with these special conditions, the 
tests to demonstrate loss of all normal electrical power must also take 
into account the following:
    a. The assumption that the failure condition occurs 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.
    b. After the un-restorable loss of normal engine generator power, 
the airplane engine restart capability is provided and operations 
continued in IMC.
    c. The airplane is demonstrated to be 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. The applicant must account for airspeed reductions resulting 
from the associated failure or failures.
    d. The airplane must provide adequate indication of loss of normal 
electrical power to direct the pilot to the non-normal procedures, and 
the operating limitations section of the AFM must incorporate non-
normal procedures that will direct the pilot to take appropriate 
actions.

    Issued in Renton, Washington, on May 2, 2017.
Michael Kaszycki,
Assistant Manager, Transport Airplane Directorate, Aircraft 
Certification Service.
[FR Doc. 2017-09441 Filed 5-9-17; 8:45 am]
 BILLING CODE 4910-13-P