[Federal Register Volume 82, Number 155 (Monday, August 14, 2017)]
[Rules and Regulations]
[Pages 37806-37811]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-17072]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2017-0316; Special Conditions No. 25-699-SC]


Special Conditions: Embraer S.A. Model ERJ 190-300 Airplane; 
Flight Envelope Protection: High Incidence Protection System

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 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 a high-incidence protection function 
that limits the angle of attack (AOA) at which the airplane can be 
flown during normal low-speed operation, and that cannot be overridden 
by the flightcrew. 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 Embraer S.A. on August 14, 2017. We 
must receive your comments by September 28, 2017.

ADDRESSES: Send comments identified by docket number FAA-2017-0316 
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/,

[[Page 37807]]

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 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: Joe Jacobsen, FAA, Airplane and Flight 
Crew Interface, ANM-111, Transport Airplane Directorate, Aircraft 
Certification Service, 1601 Lind Avenue SW., Renton, Washington 98057-
3356; telephone 425-227-2011; facsimile 425-227-1320.

SUPPLEMENTARY INFORMATION: The substance of these special conditions 
has been subject 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.
    In addition, since 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 finds it unnecessary to 
delay the effective date and finds that 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.

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 No. A57NM to include the new Model ERJ 190-300 airplane. 
The Model ERJ 190-300 airplane, which is a derivative of the Embraer 
Model ERJ 190-100 STD airplane currently approved under Type 
Certificate No. A57NM, is a 97- to 114-passenger transport-category 
airplane, designed with a new wing with a high aspect ratio and raked 
wingtip, and a new electrical-distribution system. The maximum take-off 
weight is 124,340 lbs (56,400 kg).

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.
    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 or 
unusual design feature, 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 Embraer 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 Embraer Model ERJ 190-300 airplane will incorporate the 
following novel or unusual design feature:
    A high-incidence protection function that limits the angle of 
attack (AOA) at which the airplane can be flown during normal low-speed 
operation, and that cannot be overridden by the flightcrew.

Discussion

    The Model ERJ 190-300 airplane design has a complex, full-digital 
flight-control system, referred to as fly-by-wire (FBW) architecture. 
This FBW architecture provides closed-loop flight-control laws and 
multiple protection functions.
    The Model ERJ 190-300 airplane is equipped with a high-incidence 
protection function that limits the angle of attack (AOA) at which the 
airplane can be flown during normal low-speed operation, and cannot be 
overridden by the flightcrew. The application of this AOA limit impacts 
the stall-speed determination, the stall characteristics and stall-
warning demonstration, and the longitudinal airplane-handling 
characteristics. The high-incidence protection function prevents the 
airplane from stalling at low speeds and, therefore, a stall warning 
system is backed up during normal flight conditions. If the high-
incidence protection function has a failure that is not shown to be 
extremely improbable, stall warning must be provided in a conventional 
manner. Also, the flight characteristics at the AOA for 
VCLmax (AOA at the maximum lift co-efficient and associated 
speed) must be suitable in the traditional sense. Per 14 CFR 21.16, 
therefore, special conditions are needed to address the unique features 
of the high-incidence protection function installed on the Model ERJ 
190-300 airplane.
    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 
Model ERJ 190-300 airplane. 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, these special conditions 
would apply to that model as well.

[[Page 37808]]

Conclusion

    This action affects only certain novel or unusual design features 
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.

    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 the Embraer Model ERJ 190-300 
airplane.

Flight Envelope Protection: High Incidence Protection System

    The current airworthiness standards do not contain adequate safety 
standards for the unique features of the high incidence protection 
system on the Embraer Model ERJ 190-300 airplane. Part I of the 
following special conditions are issued in lieu of the specified 
paragraphs of Sec. Sec.  25.103, 25.145, 25.201, 25.203, 25.207, and 
25.1323 of title 14, Code of Federal Regulations (CFR) or in addition 
to the requirements of Sec.  25.21. Part II are in lieu of the 
specified paragraphs of Sec. Sec.  25.103, 25.105, 25.107, 25.121, 
25.123, 25.125, 25.143, and 25.207 of title 14 CFR.

Special Conditions Part I

Stall Protection and Scheduled Operating Speeds

    The following special conditions are in lieu of Sec. Sec.  25.103, 
25.145(a), 25.145(b)(6), 25.201, 25.203, 25.207, and 25.1323(d) or in 
addition to the requirements of Sec.  25.21.

Foreword

    In the following paragraphs, ``in icing conditions'' means with the 
ice accretions (relative to the relevant flight phase) as defined in 14 
CFR part 25, Amendment 121, appendix C.
1. Definitions
    The following are terms relating to the novel or unusual design 
features these special conditions address:
     High incidence protection system: A system that operates 
directly and automatically on the airplane's flying controls to limit 
the maximum angle of attack that can be attained to a value below that 
at which an aerodynamic stall would occur.
     Alpha-limit: The maximum angle of attack at which the 
airplane stabilizes with the high incidence protection system 
operating, and the longitudinal control held on its aft stop.
     Vmin: The minimum steady flight speed in the airplane 
configuration under consideration with the high incidence protection 
system operating. See Part I, section 3 of these special conditions.
     Vmin1g: Vmin corrected to 1g conditions. See 
Part I, section 3 of these special conditions. It is the minimum 
calibrated airspeed at which the airplane can develop a lift force 
normal to the flight path and equal to its weight when at an angle of 
attack not greater than that determined for Vmin.
2. Capability and Reliability of the High Incidence Protection System
    The capability and reliability of the high incidence protection 
system can be established by flight test, simulation, and analysis as 
appropriate. The capability and reliability required are as follows:
    1. It must not be possible during pilot-induced maneuvers to 
encounter a stall, and handling characteristics must be acceptable, as 
required by section 5 of Part I of these special conditions.
    2. The airplane must be protected against stalling due to the 
effects of wind-shears and gusts at low speeds as required by section 6 
of Part I of these special conditions.
    3. The ability of the high incidence protection system to 
accommodate any reduction in stalling incidence must be verified in 
icing conditions.
    4. The high incidence protection system must be provided in each 
abnormal configuration of the high lift devices that is likely to be 
used in flight following system failures.
    5. The reliability of the system and the effects of failures must 
be acceptable in accordance with Sec.  25.1309.
3. Minimum Steady Flight Speed and Reference Stall Speed
    In lieu of Sec.  25.103, the following requirements apply:
    (a) The minimum steady flight speed, Vmin, is the final 
stabilized calibrated airspeed obtained when the airplane is 
decelerated until the longitudinal control is on its stop in such a way 
that the entry rate does not exceed 1 knot per second.
    (b) The minimum steady flight speed, Vmin, must be 
determined if it is used to determine compliance with a required 
performance standard or other requirements demonstrations in icing or 
non-icing conditions with:
    (1) The high incidence protection system operating normally;
    (2) Idle thrust and automatic thrust system (if applicable) 
inhibited;
    (3) All combinations of flap settings and landing gear position for 
which Vmin is required to be determined;
    (4) The weight used when reference stall speed, VSR, is 
being used as a factor to determine compliance with a required 
performance standard;
    (5) The most unfavorable center of gravity allowable; and
    (6) The airplane trimmed for straight flight at a speed selected by 
the applicant, but not less than 1.13 VSR and not greater 
than 1.3 VSR.
    (c) The 1-g minimum steady flight speed, Vmin1g, is the 
minimum calibrated airspeed at which the airplane can develop a lift 
force (normal to the flight path) equal to its weight, while at an 
angle of attack not greater than that at which the minimum steady 
flight speed of subparagraph (a) was determined. It must be determined 
if it is used to determine compliance with a required performance 
standard or other requirements demonstrations in icing or non-icing 
conditions.
    (d) The reference stall speed, VSR, is a calibrated 
airspeed defined by the applicant. VSR may not be less than 
a 1g stall speed. VSR must be determined in non-icing 
conditions (and as an option, in icing conditions) and expressed as:

[[Page 37809]]

[GRAPHIC] [TIFF OMITTED] TR14AU17.027

    (e) VCLmax is determined with:
    (1) Engines idling, or, if that resultant thrust causes an 
appreciable decrease in stall speed, not more than zero thrust at the 
stall speed;
    (2) The airplane in other respects (such as flaps, landing gear, 
and ice accretions) in the condition existing in the test or 
performance standard in which VSR is being used;
    (3) The weight used when VSR is being used as a factor 
to determine compliance with a required performance standard;
    (4) The center of gravity position that results in the highest 
value of reference stall speed;
    (5) The airplane trimmed for straight flight at a speed achievable 
by the automatic trim system, but not less than 1.13 VSR and 
not greater than 1.3 VSR; and
    (6) The high incidence protection system adjusted or disabled, at 
the option of the applicant, to allow higher incidence than is possible 
with the normal production system.
    (7) Starting from the stabilized trim condition, apply the 
longitudinal control to decelerate the airplane so that the speed 
reduction does not exceed 1 knot per second.
4. Stall Warning
    In lieu of Sec.  25.207, the following requirements apply:
4.1 Normal Operation
    If the capability requirements of the high incidence protection 
system are successfully demostrated, then the conditions of section 2, 
``Capability and Reliability of the High Incidence Protection System,'' 
are satisfied. These conditions provide safety equivalent to Sec.  
25.207, Stall warning, so the provision of an additional, unique 
warning device is not required.
4.2 High Incidence Protection System Failure
    Following failures of the high incidence protection system, not 
shown to be extremely improbable, such that the capability of the 
system no longer satisfies items (1), (2), and (3) of section 2, 
``Capability and Reliability of the High Incidence Protection System,'' 
stall warning must be provided and must protect against encountering 
unacceptable stall characteristics and against encountering stall.
    (a) Stall warning with the flaps and landing gear in any normal 
position must be clear and distinctive to the pilot and meet the 
requirements specified in paragraphs (d) and (e) below.
    (b) Stall warning must also be provided in each abnormal 
configuration of the high lift devices that is likely to be used in 
flight following system failures.
    (c) The warning may be furnished either through the inherent 
aerodynamic qualities of the airplane or by a device that will give 
clearly distinguishable indications under expected conditions of 
flight. However, a visual stall warning device that requires the 
attention of the crew within the cockpit is not acceptable by itself. 
If a warning device is used, it must provide a warning in each of the 
airplane configurations prescribed in paragraph (a) above and for the 
conditions prescribed in paragraphs (d) and (e) below.
    (d) In non-icing conditions stall warning must provide sufficient 
margin to prevent encountering unacceptable stall characteristics and 
encountering stall in the following conditions:
    (1) In power off (engine power or thrust at flight idle) straight 
deceleration not exceeding 1 knot per second to a speed 5 knots or 5 
percent calibrated airspeed, whichever is greater, below the warning 
onset.
    (2) In turning flight stall deceleration at entry rates up to 3 
knots per second when recovery is initiated not less than 1 second 
after the warning onset.
    (e) In icing conditions stall warning must provide sufficient 
margin to prevent encountering unacceptable characteristics and 
encountering stall, in power-off (engine power or thrust at flight 
idle) straight and turning flight decelerations not exceeding 1 knot 
per

[[Page 37810]]

second, when the pilot starts a recovery maneuver not less than three 
seconds after the onset of stall warning.
    (f) An airplane is considered stalled when the behavior of the 
airplane gives the pilot a clear and distinctive indication of an 
acceptable nature that the airplane is stalled. Acceptable indications 
of a stall, occurring either individually or in combination are:
    (1) A nose-down pitch that cannot be readily arrested;
    (2) Buffeting, of a magnitude and severity that is strong and 
effective deterrent to further speed reduction; or
    (3) The pitch control reaches the aft stop and no further increase 
in pitch attitude occurs when the control is held full aft for a short 
time before recovery is initiated.
    (g) An aircraft exhibits unacceptable characteristics during 
straight or turning flight decelerations if it is not always possible 
to produce and to correct roll and yaw by unreversed use of aileron and 
rudder controls, or abnormal nose-up pitching occurs.
5. Handling Characteristics at High Incidence
    In lieu of Sec. Sec.  25.201 and 25.203, the following requirements 
apply:
5.1 High Incidence Handling Demonstration
    In lieu of Sec.  25.201:
    (a) Maneuvers to the limit of the longitudinal control, in the 
nose-up pitch, must be demonstrated in straight flight and in 30[deg] 
banked turns with:
    (1) The high incidence protection system operating normally;
    (2) Initial power conditions of:
    i. Power off (engine power or thrust at flight idle); and
    ii. The power necessary to maintain level flight at 1.5 
VSR1, where VSR1 is the reference stall speed 
with flaps in approach position, the landing gear retracted, and 
maximum landing weight;
    (3) Flaps, landing gear, and deceleration devices in any likely 
combination of positions;
    (4) Representative weights within the range for which certification 
is requested; and
    (5) The airplane trimmed for straight flight at a speed selected by 
the applicant, but not less than 1.13 V SR and not greater than 1.3 
VSR.
    (b) The following procedures must be used to show compliance in 
non-icing and icing conditions:
    (1) Starting at a speed sufficiently above the minimum steady 
flight speed to ensure that a steady rate of speed reduction can be 
established, apply the longitudinal control so that the speed reduction 
does not exceed 1 knot per second until the control reaches the stop;
    (2) The longitudinal control must be maintained at the stop until 
the airplane has reached a stabilized flight condition and must then be 
recovered by normal recovery techniques;
    (3) Maneuvers with increased deceleration rates:
    (i) In non-icing conditions, the requirements must also be met with 
increased rates of entry to the incidence limit, up to the maximum 
practical entry rate; and
    (ii) In icing conditions, with the anti-ice system working 
normally, the requirements must also be met with increased rates of 
entry to the incidence limit, up to 3 knots per second; and
    (4) Maneuver with ice accretion prior to operation of the normal 
anti-ice system. With the ice accretion prior to operation of the 
normal anti-ice system, the requirements must also be met in 
deceleration at 1 knot per second. The deceleration must be continued 
until one second after the activation of the tactile stall warning 
system or three seconds after reaching full back stick, whichever 
occurs first. A primary ice detection system must automatically 
activate the ice protection.
5.2 Characteristics in High Incidence Maneuvers
    In lieu of Sec.  25.203:
    In icing and non-icing conditions:
    (a) Throughout maneuvers with a rate of deceleration of not more 
than 1 knot per second, both in straight flight and in 30[deg] banked 
turns, the airplane's characteristics must be as follows:
    (1) There must not be any abnormal nose-up pitching.
    (2) There must not be any uncommanded nose-down pitching, which 
would be indicative of stall. However, reasonable attitude changes 
associated with stabilizing the incidence at Alpha limit as the 
longitudinal control reaches the stop would be acceptable.
    (3) There must not be any uncommanded lateral or directional motion 
and the pilot must retain good lateral and directional control, by 
conventional use of the controls, throughout the maneuver.
    (4) The airplane must not exhibit buffeting of a magnitude and 
severity that would act as a deterrent from completing the maneuver 
specified in paragraph 5.1(a).
    (b) In maneuvers with increased rates of deceleration, some 
degradation of characteristics is acceptable, associated with a 
transient excursion beyond the stabilized Alpha limit. However, the 
airplane must not exhibit dangerous characteristics or characteristics 
that would deter the pilot from holding the longitudinal control on the 
stop for a period of time appropriate to the maneuver.
    (c) It must always be possible to reduce incidence by conventional 
use of the controls.
    (d) The rate at which the airplane can be maneuvered from trim 
speeds associated with scheduled operating speeds such as V2 
and VREF up to Alpha limit must not be unduly damped or be 
significantly slower than can be achieved on conventionally controlled 
transport airplanes.
5.3 Characteristics Up to Maximum Lift Angle of Attack
    Also in lieu of Sec.  25.201:
    (a) In non-icing conditions:
    Maneuvers with a rate of deceleration of not more than 1 knot per 
second up to the angle of attack at which VCLmax was 
obtained as defined in section 3, ``Minimum Steady Flight Speed and 
Reference Stall Speed,'' must be demonstrated in straight flight and in 
30[deg] banked turns in the following configurations:
    (1) The high incidence protection deactivated or adjusted, at the 
option of the applicant, to allow higher incidence than is possible 
with the normal production system;
    (2) Automatic thrust increase system inhibited (if applicable);
    (3) Engines idling;
    (4) Flaps and landing gear in any likely combination of positions; 
and
    (5) The airplane trimmed for straight flight at a speed selected by 
the applicant, but not less than 1.13 VSR and not greater 
than 1.3 VSR.
    (b) In icing conditions:
    Maneuvers with a rate of deceleration of not more than 1 knot per 
second up to the maximum angle of attack reached during maneuvers from 
paragraph 5.1(b)(3)(ii) must be demonstrated in straight flight with:
    (1) The high incidence protection deactivated or adjusted, at the 
option of the applicant, to allow higher incidence than is possible 
with the normal production system;
    (2) Automatic thrust increase system inhibited (if applicable);
    (3) Engines idling;
    (4) Flaps and landing gear in any likely combination of positions, 
and
    (5) The airplane trimmed for straight flight at a speed achievable 
by the automatic trim system.
    (c) During the maneuvers used to show compliance with paragraphs 
(a) and (b) above, the airplane must not exhibit dangerous 
characteristics, and it

[[Page 37811]]

must always be possible to reduce angle of attack by conventional use 
of the controls. The pilot must retain good lateral and directional 
control, by conventional use of the controls, throughout the maneuver.
6. Atmospheric Disturbances
    Operation of the high incidence protection system must not 
adversely affect aircraft control during expected levels of atmospheric 
disturbances, nor impede the application of recovery procedures in case 
of wind-shear. This must be demonstrated in non-icing and icing 
conditions.
7. Proof of Compliance
    In addition to the requirements of Sec.  25.21, the following 
requirement applies:
    (b) The flying qualities must be evaluated at the most unfavorable 
center-of-gravity position.
8. Sections 25.145(a), 25.145(b)(6), and 25.1323(d)
    The following requirements apply:
     For Sec.  25.145(a), add ``Vmin'' in lieu of 
``stall identification.''
     For Sec.  25.145(b)(6), and ``Vmin'' in lieu of 
``VSW.''
     For Sec.  25.1323(d), add ``From 1.23 VSR to 
Vmin . . .,'' in lieu of, ``1.23 VSR to the speed 
at which stall warning begins . . .,'' and, ``. . . speeds below 
Vmin . . .'' in lieu of, ``. . . speeds below stall 
warning.''

Special Conditions Part II

Credit for Robust Envelope Protection in Icing Conditions

    The following special conditions are in lieu of the specified 
paragraphs of Sec. Sec.  25.103, 25.105, 25.107, 25.121, 25.123, 
25.125, 25.143, and 25.207.
    1. Define the stall speed as provided in these special conditions, 
Part I, in lieu of Sec.  25.103.
    2. In lieu of Sec.  25.105(a)(2)(i), the following requirement 
applies:
    (i) The V2 speed scheduled in non-icing conditions does 
not provide the maneuvering capability specified in Sec.  25.143(h) for 
the takeoff configuration, or
    3. In lieu of Sec.  25.107(c) and (g), the following requirements 
apply, with additional sections (c') and (g'):
    Takeoff speeds:
    (c) In non-icing conditions V2, in terms of calibrated 
airspeed, must be selected by the applicant to provide at least the 
gradient of climb required by Sec.  25.121(b) but may not be less 
than--
    (1) V2MIN;
    (2) VR plus the speed increment attained (in accordance 
with Sec.  25.111(c)(2)) before reaching a height of 35 feet above the 
takeoff surface; and
    (3) A speed that provides the maneuvering capability specified in 
Sec.  25.143(h).
    (c') In icing conditions with the ``takeoff ice'' accretion defined 
in part 25, appendix C, V2 may not be less than--
    (1) The V2 speed determined in non-icing conditions; and
    (2) A speed that provides the maneuvering capability specified in 
Sec.  25.143(h).
    (g) In non-icing conditions, VFTO, in terms of 
calibrated airspeed, must be selected by the applicant to provide at 
least the gradient of climb required by Sec.  25.121(c), but may not be 
less than--
    (1) 1.18 VSR; and
    (2) A speed that provides the maneuvering capability specified in 
Sec.  25.143(h).
    (g') In icing conditions with the ``final takeoff ice'' accretion 
defined in part 25, appendix C, VFTO, may not be less than--
    (1) The VFTO speed determined in non-icing conditions.
    (2) A speed that provides the maneuvering capability specified in 
Sec.  25.143(h).
    4. In lieu of Sec. Sec.  25.121(b)(2)(ii)(A), 25.121(c)(2)(ii)(A), 
and 25.121(d)(2)(ii), the following requirements apply:
    In lieu of Sec.  25.121(b)(2)(ii)(A):
    (A) The V2 speed scheduled in non-icing conditions does 
not provide the maneuvering capability specified in Sec.  25.143(h) for 
the takeoff configuration; or
    In lieu of Sec.  25.121(c)(2)(ii)(A):
    (A) The VFTO speed scheduled in non-icing conditions 
does not provide the maneuvering capability specified in Sec.  
25.143(h) for the en-route configuration; or
    In lieu of Sec.  25.121(d)(2)(ii):
    (d)(2) The requirements of subparagraph (d)(1) of this paragraph 
must be met: (ii) In icing conditions with the approach ice accretion 
defined in appendix C, in a configuration corresponding to the normal 
all-engines-operating procedure in which Vmin1g for this 
configuration does not exceed 110% of the Vmin1g for the 
related all-engines-operating landing configuration in icing, with a 
climb speed established with normal landing procedures, but not more 
than 1.4 VSR (VSR determined in non-icing 
conditions).
    5. In lieu of Sec.  25.123(b)(2)(i), the following requirements 
apply:
    (i) The minimum en-route speed scheduled in non-icing conditions 
does not provide the maneuvering capability specified in Sec.  
25.143(h) for the en-route configuration, or
    6. In lieu of Sec. Sec.  25.125(b)(2)(ii)(B) and 
25.125(b)(2)(ii)(C), the following requirements apply:
    (B) A speed that provides the maneuvering capability specified in 
Sec.  25.143(h) with the landing ice accretion defined in part 25, 
appendix C.
    (C) 1.17 Vmin1g.
    7. In lieu of Sec.  25.143(j)(1), the following requirement 
applies:
    (1) The airplane is controllable in a pull-up maneuver up to 1.5 g 
load factor or lower if limited by angle of attack protection; and
    8. In lieu of Sec.  25.207, Stall warning, to read as the 
requirements defined in these special conditions Part I, Section 4.

    Issued in Renton, Washington, on July 31, 2017.
Victor Wicklund,
Manager, Transport Standards Branch, Aircraft Certification Service.
[FR Doc. 2017-17072 Filed 8-11-17; 8:45 am]
 BILLING CODE 4910-13-P