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Rules and Regulations Federal Register

55221 

Vol. 80, No. 178 

Tuesday, September 15, 2015 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 25 

[Docket No. FAA–2015–1940; Special 

Conditions No. 25–597–SC] 

Special Conditions: Bombardier 

Aerospace Inc. Model BD–500–1A10 

and BD–500–1A11 Airplanes; FlightEnvelope Protection, High Incidence 

Protection Function 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final special conditions, request 

for comment. 

SUMMARY: These special conditions are 

issued for the Bombardier Aerospace 

Inc. Model BD–500–1A10 and –A11 

airplanes. These airplanes will have a 

novel or unusual design feature when 

compared to the state of technology and 

design envisioned in the airworthiness 

standards for transport-category 

airplanes. This design feature is a high 

incidence protection system that limits 

the angle of attack at which the airplane 

can be flown during normal low-speed 

operation. 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 Aerospace Inc. on 

September 15, 2015. We must receive 

your comments by October 30, 2015. 

ADDRESSES: Send comments identified 

by docket number FAA–2015–1940 

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), 

as well as at http://DocketsInfo.dot 

.gov/. 

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 Branch, ANM–111, 

Transport Airplane Directorate, Aircraft 

Certification Service, 1601 Lind Avenue 

SW., Renton, Washington 98057–3356; 

telephone (425) 227–2011; facsimile 

(425) 227–1149. 

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 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 December 10, 2009, Bombardier 

Aerospace Inc. applied for a type 

certificate for their new Model BD–500- 

1A10 and –1A11 airplanes. The Model 

BD–500–1A10 and –1A11 airplanes are 

swept-wing monoplanes with a 

pressurized cabin, and share an 

identical supplier base and significant 

common design elements. The fuselage 

is aluminum alloy material, blended 

double-bubble fuselage, and is sized for 

nominal five-abreast seating. The 

powerplant for each airplane model 

includes two under-wing Pratt and 

Whitney PW1524G ultra-high bypass, 

geared turbofan engines. Flight controls 

are fly-by-wire with two passive/

uncoupled side sticks. Avionics include 

five landscape primary flightdeck 

displays. The wingspans are 115 feet; 

heights are 37.75 feet; and length is 

114.75 feet for the Model BD–500–1A10, 

and 127 feet for the Model BD–500– 

1A11. Passenger capacity is 110 for the 

Model BD–500–1A10, and 125 for the 

Model BD–500–1A11. Maximum takeoff 

weight is 131,000 pounds for the Model 

BD–500–1A10, and 144,000 pounds for 

the Model BD–500–1A11. Maximum 

takeoff thrust is 21,000 pounds for the 

Model BD–500–1A10, and 23,300 

pounds for the Model BD–500–1A11. 

Range is 3,394 miles, and operating 

altitude is 41,000 feet, for both airplane 

models. 

Sections specified in these special 

conditions that address the high 

incidence protection system will replace 

common sections found in the 

applicable sections of Title 14, Code of 

Federal Regulations (14 CFR) part 25. 

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55222 Federal Register / Vol. 80, No. 178 / Tuesday, September 15, 2015 / Rules and Regulations 

Type Certification Basis 

Under the provisions of 14 CFR 21.17, 

Bombardier Aerospace Inc. must show 

that the Model BD–500-1A10 and –1A11 

airplanes meet the applicable provisions 

of part 25 as amended by Amendments 

25–1 through 25–129. 

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 BD–500–1A10 and –1A11 

airplanes because of a novel or unusual 

design feature, special conditions are 

prescribed under the provisions of 

§ 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 or similar novel 

or unusual design feature, the special 

conditions would also apply to the other 

model under § 21.101. 

In addition to the applicable 

airworthiness regulations and special 

conditions, the Model BD–500–1A10 

and –1A11 airplanes must comply with 

the fuel-vent and exhaust-emission 

requirements of 14 CFR part 34, and the 

noise-certification requirements of 14 

CFR part 36; and the FAA must issue a 

finding of regulatory adequacy under 

§ 611 of Public Law 92–574, the ‘‘Noise 

Control Act of 1972.’’ 

The FAA issues special conditions, as 

defined in 14 CFR 11.19, in accordance 

with § 11.38, and they become part of 

the type certification basis under 

§ 21.17(a)(2). 

Novel or Unusual Design Features 

The Model BD–500–1A10 and –1A11 

airplanes will incorporate the following 

novel or unusual design feature: 

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 that cannot be 

overridden by the flightcrew. The 

application of this angle-of-attack limit 

impacts the stall-speed determination, 

the stall-characteristics and stallwarning demonstration, and the 

longitudinal-handling characteristics. 

The current regulations do not address 

this type of protection feature. 

Discussion 

The high incidence protection 

function prevents the airplane from 

stalling at low speeds and, therefore, a 

stall-warning system is not needed 

during normal flight conditions. If a 

failure of the high incidence protection 

function occurs that is not shown to be 

extremely improbable, stall warning 

must be provided in a conventional 

manner. Also, the flight characteristics 

at the angle of attack for maximum-lift 

coefficient (CLmax) must be suitable in 

the traditional sense. 

These special conditions address this 

novel or unusual design feature on the 

Bombardier Model BD–500–1A10 and 

–1A11 airplanes. These special 

conditions, which include airplane 

performance requirements, establish a 

level of safety equivalent to the current 

regulations for reference stall speeds, 

stall warning, stall characteristics, and 

miscellaneous other minimum reference 

speeds. 

These proposed special conditions for 

the Bombardier Model BD–500–1A10 

and –1A11 airplanes present 

amendments to the appropriate 

regulations to accommodate the unique 

features of the high incidence protection 

function. 

Applicability 

As discussed above, these special 

conditions are applicable to the 

Bombardier Model BD–500–1A10 and 

–1A11 airplanes. Should Bombardier 

apply at a later date for a change to the 

type certificate to include another 

model incorporating the same or similar 

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 

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. 

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, the Federal Aviation 

Administration (FAA) issues the 

following special conditions as part of 

the type certification basis for 

Bombardier Model BD–500–1A10 and 

–1A11 airplanes. 

Flight Envelope Protection: High 

Incidence Protection System 

Special Conditions Part I 

Stall Protection and Scheduled 

Operating Speeds 

The following special conditions are 

in lieu of §§ 25.21(b), 25.103, 25.145(a), 

25.145(b)(6), 25.201, 25.203, 25.207, and 

25.1323(d). 

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: 

• 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. 

• Vmin 1g: 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 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. The capability and 

reliability required are: 

1. It must not be possible during pilotinduced maneuvers to encounter a stall, 

and handling characteristics must be 

acceptable, as required by Part I, section 

5 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 Part I, section 6 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 are likely to be used in 

flight following system failures. 

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Federal Register / Vol. 80, No. 178 / Tuesday, September 15, 2015 / Rules and Regulations 55223 

5. The reliability of the system and 

the effects of failures must be acceptable 

in accordance with § 25.1309. 

3. Minimum Steady Flight Speed and 

Reference Stall Speed 

In lieu of § 25.103, the following 

applies: 

(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: 

(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 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 subparagraph (a) was 

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 1g 

stall speed. VSR must be determined in 

non-icing conditions and expressed as: 

(e) VCLmax is determined in non-icing 

conditions 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 and landing gear) 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; 

(6) Reserved. 

(7) 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 

(8) 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 § 25.207, the following 

apply: 

4.1 Normal Operation 

If the design meets all conditions of 

section 2 of these special conditions, 

then the airplane need not provide stall 

warning during normal operation. The 

conditions of section 2 provide safety 

equivalent to § 25.207, ‘‘Stall warning,’’ 

so the provision of an additional, 

unique warning device for normal 

operations is not required. 

4.2 High Incidence Protection System 

Failure 

For any failure 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 section 2 of these 


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55224 Federal Register / Vol. 80, No. 178 / Tuesday, September 15, 2015 / Rules and Regulations 

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 paragraphs (d) and (e), 

below. 

(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 all 

expected conditions of flight. However, 

a visual stall-warning device that 

requires the attention of the crew within 

the flightdeck 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 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 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: 

(1) A nose-down pitch that cannot be 

readily arrested; 

(2) Buffeting, of a magnitude and 

severity that is a strong and effective 

deterrent to further speed reduction; 

(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 airplane 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 noseup pitching occurs. 

5. Handling Characteristics at High 

Incidence 

In lieu of §§ 25.201 and 25.203, the 

following apply: 

5.1 High Incidence Handling 

Demonstration 

In lieu of § 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-degree banked turns 

with: 

(1) The high incidence protection 

system operating normally; 

(2) Initial power conditions of: 

i. Power off; 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) None. 

(4) Flaps, landing gear, and 

deceleration devices in any likely 

combination of positions; 

(5) Representative weights within the 

range for which certification is 

requested; and 

(6) 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: 

(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 rate 

achievable; and 

(ii) In icing conditions, with the antiice system working normally, the 

requirements must also be met with 

increased rates of entry to the incidence 

limit, up to 3 knots per second. 

(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 up to 

full back stick. 

5.2 Characteristics in High Incidence 

Maneuvers 

In lieu of § 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-degree 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 

In lieu of § 25.201: 

(a) In non-icing conditions: 

Maneuvers with a rate of deceleration 

of not more than 1 knot per second, up 

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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-degree 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 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)(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 

must always be possible to reduce the 

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 airplane 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 § 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 § 25.145(a), add ‘‘Vmin’’ in lieu 

of ‘‘stall identification.’’ 

• For § 25.145(b)(6), add ‘‘Vmin’’ in 

lieu of ‘‘VSW.’’ 

• For § 25.1323(d), add ‘‘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. . . .’’ 

Special Conditions Part II—Credit for 

Robust Envelope Protection in Icing 

Conditions 

The following special conditions are 

in lieu of the specified paragraphs of 

§§ 25.103, 25.105, 25.107, 25.121, 

25.123, 25.125, 25.143, and 25.207. 

1. In lieu of § 25.103, define the stall 

speed as provided in Part I of these 

special conditions. 

2. In lieu of § 25.105(a)(2)(i), the 

following applies: 

(i) The V2 speed scheduled in nonicing conditions does not provide the 

maneuvering capability specified in 

§ 25.143(h) for the takeoff configuration, 

or apply 25.105(a)(2)(ii) unchanged. 

3. In lieu of § 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 

§ 25.121(b), but may not be less than— 

(1) V2MIN; 

(2) VR plus the speed increment 

attained (in accordance with 

§ 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 

§ 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 nonicing conditions; and 

(2) A speed that provides the 

maneuvering capability specified in 

§ 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 

§ 25.121(c), but may not be less than— 

(1) 1.18 VSR; and 

(2) A speed that provides the 

maneuvering capability specified in 

§ 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 

§ 25.143(h). 

4. In lieu of §§ 25.121(b)(2)(ii)(A), 

25.121(c)(2)(ii)(A), and 25.121(d)(2)(ii), 

the following apply: 

In lieu of § 25.121(b)(2)(ii)(A): 

(A) The V2 speed scheduled in nonicing conditions does not provide the 

maneuvering capability specified in 

§ 25.143(h) for the takeoff configuration; 

or 

In lieu of § 25.121(c)(2)(ii)(A): 

(A) The VFTO speed scheduled in nonicing conditions does not provide the 

maneuvering capability specified in 

§ 25.143(h) for the en-route 

configuration; or 

In lieu of § 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-enginesoperating 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 § 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 § 25.143(h) for the en-route 

configuration, or 

6. In lieu of § 25.125(b)(2)(ii)(B) and 

§ 25.125(b)(2)(ii)(C), the following 

applies: 

(B) A speed that provides the 

maneuvering capability specified in 

§ 25.143(h) with the approach ice 

accretion defined in 14 CFR part 25, 

appendix C. 

7. In lieu of § 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 § 25.207, ‘‘Stall warning,’’ 

to read as the requirements defined in 

these special conditions Part I, section 

4. 

Issued in Renton, Washington, on 

September 1, 2015. 

Michael Kaszycki, 

Acting Manager, Transport Airplane 

Directorate, Aircraft Certification Service. 

[FR Doc. 2015–23101 Filed 9–14–15; 8:45 am] 

BILLING CODE 4910–13–P 

mstockstill on DSK4VPTVN1PROD with RULES