Special Conditions: Bombardier Aerospace Inc. Model BD-500-1A10 and BD-500-1A11 Airplanes; Flight-Envelope Protection, High Incidence Protection Function, 55221-55225 [2015-23101]

Download as PDF 55221 Rules and Regulations Federal Register Vol. 80, No. 178 Tuesday, September 15, 2015 This section of the FEDERAL REGISTER contains regulatory documents having general applicability and legal effect, most of which are keyed to and codified in the Code of Federal Regulations, which is published under 50 titles pursuant to 44 U.S.C. 1510. The Code of Federal Regulations is sold by the Superintendent of Documents. Prices of new books are listed in the first FEDERAL REGISTER issue of each week. 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 Federal Aviation Administration (FAA), DOT. ACTION: Final special conditions, request for comment. AGENCY: 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. mstockstill on DSK4VPTVN1PROD with RULES SUMMARY: VerDate Sep<11>2014 19:08 Sep 14, 2015 Jkt 235001 • 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 PO 00000 Frm 00001 Fmt 4700 Sfmt 4700 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–5001A10 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. E:\FR\FM\15SER1.SGM 15SER1 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). mstockstill on DSK4VPTVN1PROD with RULES 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 VerDate Sep<11>2014 19:08 Sep 14, 2015 Jkt 235001 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), PO 00000 Frm 00002 Fmt 4700 Sfmt 4700 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. E:\FR\FM\15SER1.SGM 15SER1 Federal Register / Vol. 80, No. 178 / Tuesday, September 15, 2015 / Rules and Regulations mstockstill on DSK4VPTVN1PROD with RULES 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: (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; VerDate Sep<11>2014 19:08 Sep 14, 2015 Jkt 235001 (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: (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. 4.1 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. Stall Warning In lieu of § 25.207, the following apply: PO 00000 Frm 00003 Fmt 4700 Sfmt 4700 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 E:\FR\FM\15SER1.SGM 15SER1 ER15SE15.002</GPH> 5. The reliability of the system and the effects of failures must be acceptable in accordance with § 25.1309. 55223 mstockstill on DSK4VPTVN1PROD with RULES 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 VerDate Sep<11>2014 19:08 Sep 14, 2015 Jkt 235001 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. 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. Handling Characteristics at High Incidence 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. 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 PO 00000 Frm 00004 Fmt 4700 Sfmt 4700 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 E:\FR\FM\15SER1.SGM 15SER1 Federal Register / Vol. 80, No. 178 / Tuesday, September 15, 2015 / Rules and Regulations 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 mstockstill on DSK4VPTVN1PROD with RULES 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. VerDate Sep<11>2014 19:08 Sep 14, 2015 Jkt 235001 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— PO 00000 Frm 00005 Fmt 4700 Sfmt 9990 55225 (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 E:\FR\FM\15SER1.SGM 15SER1

Agencies

[Federal Register Volume 80, Number 178 (Tuesday, September 15, 2015)]
[Rules and Regulations]
[Pages 55221-55225]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-23101]



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Rules and Regulations
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains regulatory documents 
having general applicability and legal effect, most of which are keyed 
to and codified in the Code of Federal Regulations, which is published 
under 50 titles pursuant to 44 U.S.C. 1510.

The Code of Federal Regulations is sold by the Superintendent of Documents. 
Prices of new books are listed in the first FEDERAL REGISTER issue of each 
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Federal Register / Vol. 80, No. 178 / Tuesday, September 15, 2015 / 
Rules and Regulations

[[Page 55221]]



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; Flight-Envelope 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.

[[Page 55222]]

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 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 or similar 
novel or unusual design feature, the special conditions would also 
apply to the other model under Sec.  21.101.
    In addition to the applicable airworthiness regulations and special 
conditions, the Model 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 Sec.  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 Sec.  11.38, and they become part of the type 
certification basis under Sec.  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 stall-warning 
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 Sec. Sec.  
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 pilot-induced 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.

[[Page 55223]]

    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 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:
[GRAPHIC] [TIFF OMITTED] TR15SE15.002

    (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 Sec.  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 Sec.  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

[[Page 55224]]

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 nose-up pitching occurs.

5. Handling Characteristics at High Incidence

    In lieu of Sec. Sec.  25.201 and 25.203, the following 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-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 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.
    (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 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-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 Sec.  25.201:
    (a) In non-icing conditions:
    Maneuvers with a rate of deceleration of not more than 1 knot per 
second, up

[[Page 55225]]

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 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), add ``Vmin'' in lieu of 
``stall identification.''
     For Sec.  25.145(b)(6), add ``Vmin'' in lieu of 
``VSW.''
     For Sec.  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 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 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, 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