[Federal Register Volume 83, Number 84 (Tuesday, May 1, 2018)]
[Rules and Regulations]
[Pages 18934-18938]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-09126]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2018-0335; Special Conditions No. 25-725-SC]


Special Conditions: Bombardier Inc., Model BD-700-2A12 and BD-
700-2A13 Series Airplanes; 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 Bombardier Inc. 
(Bombardier), Model BD-700-2A12 and BD-700-2A13 series airplanes. These 
airplanes 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 system that replaces the stall warning system during normal 
operating conditions, prohibits the airplane from stalling, limits the 
angle of attack at which the airplane can be flown during normal low 
speed operation, and cannot be overridden by the flight crew. 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 Bombardier Inc. on May 1, 2018. Send 
comments on or before June 15, 2018.

ADDRESSES: Send comments identified by Docket No. FAA-2018-0335 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: Joe Jacobsen, FAA, Airplane and Flight 
Crew Interface Section, AIR-671, Transport Standards Branch, Policy and 
Innovation Division, Aircraft Certification Service, 2200 South 216th 
Street, Des Moines, Washington 98198-6547; telephone 206-231-3158; 
email [email protected].

SUPPLEMENTARY INFORMATION: The substance of these special conditions 
previously has been published in the Federal Register for public 
comment. These special conditions have 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, 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

    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 May 30, 2012, Bombardier applied for an amendment to Type 
Certificate No. T00003NY to include the new Model BD-700-2A12 and BD-
700-2A13 series airplanes. The Bombardier Model BD-700-2A12 and BD-700-
2A13 series airplanes, which are derivatives of the Model BD-700 
airplane currently approved under Type Certificate No. T00003NY, are 
business jets, with a maximum certified passenger capacity of 19. The 
maximum takeoff weight of Model BD-700-2A12 is 106,250 lbs. and 104,800 
lbs. for the Model BD-700-2A13.

[[Page 18935]]

Type Certification Basis

    Under the provisions of title 14, Code of Federal Regulations (14 
CFR) 21.101, Bombardier must show that the Model BD-700-2A12 and BD-
700-2A13 series airplanes meet the applicable provisions of the 
regulations listed in Type Certificate No. T00003NY 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 BD-700-2A12 and BD-700-2A13 series 
airplanes 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.
    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 BD-700-2A12 and BD-700-2A13 series airplanes will 
incorporate the following novel or unusual design features:
    A high incidence protection system that replaces the stall warning 
system during normal operating conditions, prohibits the airplane from 
stalling, limits the angle of attack at which the airplane can be flown 
during normal low speed operation, and cannot be overridden by the 
flight crew. The application of this angle-of-attack limit impacts the 
stall speed determination, the stall characteristics and stall-warning 
demonstration, and the longitudinal handling characteristics.

Discussion

    The high incidence protection function prevents the airplanes from 
stalling at low speeds and, therefore, a stall warning system is not 
needed during normal flight conditions. If there is a failure of the 
high incidence protection function that is not shown to be extremely 
improbable, theses special conditions will apply. For example, stall 
warning must be provided in a conventional manner and the flight 
characteristics at the angle of attack for CLMAX must be 
suitable in the traditional sense.
    These special conditions addressing the high incidence protection 
system will replace the applicable sections of 14 CFR part 25. Part I 
of the following special conditions is in lieu of Sec. Sec.  25.21(b), 
25.103, 25.145(a), 25.145(b)(6), 25.201, 25.203, 25.207, and 
25.1323(d). Part II is in lieu of Sec. Sec.  25.103, 25.105(a)(2)(i), 
25.107(c) and (g), 25.121(b)(2)(ii)(A), 25.121(c)(2)(ii)(A), 
25.121(d)(2)(ii), 25.123(b)(2)(i), 25.125(b)(2)(ii)(B), and 
25.143(j)(2)(i).
    These special conditions address this novel or unusual design 
feature on the Bombardier Model BD-700-2A12 and BD-700-2A13, and 
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 
Bombardier Model BD-700-2A12 and BD-700-2A13 series airplanes. Should 
Bombardier 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 certain novel or unusual design features 
on one model series of airplanes. 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 Bombardier Model BD-700-2A12 and BD-
700-2A13 series airplanes.

Part I: Stall Protection and Scheduled Operating Speeds

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
    These special conditions use terminology that does not appear in 14 
CFR part 25. For the purpose of these special conditions, the following 
terms describe certain aspects of this novel or unusual design feature:
    a. High incidence protection system: A system that operates 
directly and automatically on the airplane's flight controls to limit 
the maximum angle of attack that can be attained to a value below that 
at which an aerodynamic stall would occur.
    b. 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.
    c. Vmin: The minimum steady flight speed in the 
airplane's configuration under consideration with the high incidence 
protection system operating. See Part 1, paragraph 3 of these Special 
Conditions.
    d. Vmin1g: Vmin corrected to 1g conditions. 
See Part 1, paragraph 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 applicant must establish the capability and reliability of the 
high incidence protection system. The applicant may establish this 
capability and reliability by flight test, simulation, or analysis as 
appropriate. The capability and reliability required are:
    a. It must not be possible during pilot induced maneuvers to 
encounter a stall and handling characteristics must be acceptable, as 
required by Part 1, paragraph 5 of these Special Conditions;
    b. The airplane must be protected against stalling due to the 
effects of wind-shears and gusts at low speeds as required by Part 1, 
paragraph 6 of these Special Conditions;
    c. The ability of the high incidence protection system to 
accommodate any reduction in stalling incidence must be verified in 
icing conditions;
    d. The high incidence protection system must be provided in each

[[Page 18936]]

abnormal configuration of the high lift devices that is likely to be 
used in flight following system failures; and
    e. 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 in icing and non-icing conditions with:
    i. The high incidence protection system operating normally.
    ii. Idle thrust and automatic thrust system (if applicable) 
inhibited;
    iii. All combinations of flaps setting and landing gear position 
for which Vmin is required to be determined;
    iv. The weight used when reference stall speed, VSR, is 
being used as a factor to determine compliance with a required 
performance standard;
    v. The most unfavorable center of gravity allowable; and
    vi. The airplane trimmed for straight flight at a speed achievable 
by the automatic trim system.
    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 Part 1, paragraph 3(a) of these special conditions is 
determined. It must be determined in icing and non-icing conditions.
    d. The reference stall speed, VSR, is a calibrated 
airspeed defined by the applicant. VSR may not be less than 
a 1-g stall speed. VSR must be determined in non-icing 
conditions and expressed as:
[GRAPHIC] [TIFF OMITTED] TR01MY18.000

where--
VCLmax = Calibrated airspeed obtained when the load-
factor-corrected lift coefficient
[GRAPHIC] [TIFF OMITTED] TR01MY18.001

 is first a maximum during the maneuver
 prescribed in condition (3)(e)(viii) of
 these special conditions.
nzw = Load factor normal to the flight path at 
VCLmax
W = Airplane gross weight;
S = Aerodynamic reference wing area; and
q = Dynamic pressure.

    e. VCLmax is determined in non-icing conditions with:
    i. Engines idling, or, if that resultant thrust causes an 
appreciable decrease in stall speed, not more than zero thrust at the 
stall speed;
    ii. The airplane in other respects (such as flaps and landing gear) 
in the condition existing in the test or performance standard in which 
VSR is being used;
    iii. The weight used when VSR is being used as a factor 
to determine compliance with a required performance standard;
    iv. The center of gravity position that results in the highest 
value of reference stall speed;
    v. 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;
    vi. None.
    vii. The High Incidence Protection System adjusted, at the option 
of the applicant, to allow higher incidence than is possible with the 
normal production system; and
    viii. 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 design meets all conditions of Part 1, paragraph 2 of these 
special conditions, then the airplane need not provide stall warning 
during normal operation. The conditions of Part 1, paragraph 2 of these 
special conditions provide a level of safety equal to the intent of 
Sec.  25.207, ``Stall Warning'', so the provision of an additional, 
unique warning device is not required.
4.2 High Incidence Protection System Failure
    For any failures of the high incidence protection system that the 
applicant cannot show to be extremely improbable, and that result in 
the capability of the system no longer satisfying any part of paragraph 
2(a), (b), and (c) of Part 1 of these special conditions, the design 
must provide stall warning that protects against encountering 
unacceptable stall characteristics and against encountering stall.
    a. This 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 Part 1, paragraphs 4.2(d) and 4.2(e) of 
these special conditions.
    b. The design must also provide this stall warning in each abnormal 
configuration of the high lift devices that is likely to be used in 
flight following system failures.
    c. The design may furnish this stall warning 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 flight deck 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 4.2(a) and for 
the conditions prescribed in paragraphs 4.2(d) and 4.2(e) of Part 1 of 
these special conditions.
    d. In non-icing conditions, stall warning must provide sufficient 
margin to prevent encountering unacceptable stall characteristics and 
encountering stall in the following conditions:
    i. In power off straight deceleration not exceeding 1 knot per 
second to a speed of 5 knots or 5 percent calibrated airspeed (CAS), 
whichever is greater, below the warning onset.
    ii. In turning flight, stall deceleration at entry rates up to 3 
knots per second when recovery is initiated not less than one 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 straight and turning flight 
decelerations not exceeding 1 knot per 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:
    i. A nose-down pitch that cannot be readily arrested;
    ii. Buffeting, of a magnitude and severity that is strong and 
effective deterrent to further speed reduction; or
    iii. 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

[[Page 18937]]

and yaw by unreversed use of aileron and rudder controls, or abnormal 
nose-up pitching occurs.
5. Handling Characteristics at High Incidence
5.1 High Incidence Handling Demonstrations
    In lieu of Sec.  25.201, the following is required:
    (a) Maneuvers to the limit of the longitudinal control, in the nose 
up sense, must be demonstrated in straight flight and in 30-degree 
banked turns with:
    (i) The high incidence protection system operating normally;
    (ii) Initial power conditions of:
    (1) Power off; and
    (2) 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.
    (iii) None.
    (iv) Flaps, landing gear, and deceleration devices in any likely 
combination of positions;
    (v) Representative weights within the range for which certification 
is requested; and
    (vi) The airplane trimmed for straight flight at a speed achievable 
by the automatic trim system.
    (b) The following procedures must be used to show compliance in 
non-icing and icing conditions:
    i. 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;
    ii. 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;
    iii. Maneuvers with increased deceleration rates;
    (1) In non-icing conditions, the requirements must also be met with 
increased rates of entry to the incidence limit, up to the maximum rate 
achievable; and
    (2) 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.
    iv. Maneuver with ice accretion prior to operation of the normal 
anti-ice system.
    v. With the ice accretion prior to operation of the normal anti-ice 
system, the requirement must also be met in deceleration at 1 knot per 
second up to full back stick.
5.2 Characteristics of High Incidence Maneuvers
    In lieu of Sec.  25.203, the following requirements apply:
    a. Throughout maneuvers with a rate of deceleration of not more 
than 1 knot per second, both in straight flight and in 30-degree banked 
turns, the airplane's characteristics must be as follows:
    i. There must not be any abnormal nose-up pitching.
    ii. 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.
    iii. 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.
    iv. The airplane must not exhibit buffeting of a magnitude and 
severity that would act as a deterrent from completing the maneuver 
specified in 5.1(a) of these special conditions.
    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

    In lieu of Sec.  25.201, the following requirements apply:
    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 paragraph 3 of Part 1 of these special 
conditions, must be demonstrated in straight flight and in 30-degree 
banked turns in the following configurations:
    i. 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;
    ii. Automatic thrust increase system inhibited (if applicable);
    iii. Engines idling;
    iv. Flaps and landing gear in any likely combination of positions; 
and
    v. The airplane trimmed for straight flight at a speed achievable 
by the automatic trim system.
    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)(iii)(2) of these special conditions must be 
demonstrated in straight flight with:
    i. 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;
    ii. Automatic thrust increase system inhibited (if applicable);
    iii. Engines idling;
    iv. Flaps and landing gear in any likely combination of positions;
    v. 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 
5.3(a) and (b) of these special conditions the airplane must not 
exhibit dangerous characteristics and it 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 lieu of Sec.  25.21(b), ``[Reserved],'' the design must meet the 
following requirement:
    (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 design must meet the following modified requirements:
     For Sec.  25.145(a), ``Vmin'' in lieu of 
``stall identification.''

[[Page 18938]]

     For Sec.  25.145(b)(6), ``Vmin'' in lieu of 
``VSW.''
     For Sec.  25.1323(d), ``From 1.23 VSR to 
Vmin . . .,'' in lieu of ``1.23 VSR to stall 
warning speed . . .,'' and, ``. . . speeds below Vmin . . 
.'' in lieu of ``. . . speeds below stall warning . . . .''

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. In lieu of Sec.  25.103, define the stall speed as provided in 
Part I, paragraph 3 of these special conditions.
    2. In lieu of Sec.  25.105(a)(2)(i), the following 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 apply 25.105(a)(2)(ii) unchanged.
    3. In lieu of Sec.  25.107(c') and (g'), the following apply, with 
additional sections (c') and (g'):
    (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 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 
14 CFR part 25, appendix C, in a configuration corresponding to the 
normal all-engines-operating procedure in which Vmin1g for 
this configuration does not exceed 110 percent 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 applies:
    (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.  25.125(b)(2)(ii)(B) and Sec.  
25.125(b)(2)(ii)(C), the following applies:
    (B) A speed that provides the maneuvering capability specified in 
Sec.  25.143(h) with the approach ice accretion defined in 14 CFR part 
25, appendix C.
    7. In lieu of Sec.  25.143(j)(2)(i), the following applies:
    (i) 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.
    8. In lieu of Sec.  25.207, ``Stall warning,'' to read as the 
requirements defined in these special conditions Part I, paragraph 4.

    Issued in Des Moines, Washington, on April 25, 2018.
Suzanne Masterson,
Acting Manager, Transport Standards Branch, Policy and Innovation 
Division, Aircraft Certification Service.
[FR Doc. 2018-09126 Filed 4-30-18; 8:45 am]
BILLING CODE 4910-13-P