11556 Federal Register / Vol. 78, No. 33 / Tuesday, February 19, 2013 / Rules and Regulations 

load condition at design maneuvering 

speed (VA), in which the cockpit roll 

control is returned to neutral following 

the initial roll input. 

These special conditions differ from 

similar special conditions previously 

issued on this topic. These special 

conditions are limited to the roll axis 

only, whereas other special conditions 

also included pitch and yaw axes. 

Special conditions are no longer needed 

for the yaw axis because 14 CFR 25.351 

was revised at Amendment 25–91 to 

take into account effects of an electronic 

flight control system. No special 

conditions are needed for the pitch axis 

because the method that Embraer S.A. 

proposed for the pitch maneuver takes 

into account effects of an electronic 

flight control system. 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. 

Discussion of Comments 

Notice of proposed special conditions 

No. 25–12–15–SC for the Embraer S.A. 

EMB–550 airplanes was published in 

the Federal Register on November 26, 

2012 (77 FR 70384). No comments were 

received, and the special conditions are 

adopted as proposed. 

Applicability 

As discussed above, these special 

conditions are applicable to the Model 

EMB–550 airplane. Should Embraer 

S.A. apply at a later date for a change 

to the type certificate to include another 

model incorporating the same novel or 

unusual design feature, the special 

conditions would apply to that model as 

well. 

Conclusion 

This action affects only certain novel 

or unusual design features on one model 

EMB–550 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, pursuant to the 

authority delegated to me by the 

Administrator, the following special 

conditions are issued as part of the type 

certification basis for Embraer S.A. 

Model EMB–550 airplanes. 

1. Design Roll Maneuver for 

Electronic Flight Controls. 

In lieu of compliance to 14 CFR 

25.349(a), the Embraer S.A. Model 

EMB–550 airplane must comply with 

the following. 

The following conditions, speeds, and 

cockpit roll control motions (except as 

the motions may be limited by pilot 

effort) must be considered in 

combination with an airplane load 

factor of zero and of two-thirds of the 

positive maneuvering factor used in 

design. In determining the resulting 

control surface deflections, the torsional 

flexibility of the wing must be 

considered in accordance with 14 CFR 

25.301(b). 

(a) Conditions corresponding to 

steady rolling velocities must be 

investigated. In addition, conditions 

corresponding to maximum angular 

acceleration must be investigated for 

airplanes with engines or other weight 

concentrations outboard of the fuselage. 

For the angular acceleration conditions, 

zero rolling velocity may be assumed in 

the absence of a rational time history 

investigation of the maneuver. 

(b) At VA, sudden movement of the 

cockpit roll control up to the limit is 

assumed. The position of the cockpit 

roll control must be maintained until a 

steady roll rate is achieved and then 

must be returned suddenly to the 

neutral position. 

(c) At VC, the cockpit roll control 

must be moved suddenly and 

maintained so as to achieve a roll rate 

not less than that obtained in paragraph 

(b). 

(d) At VD, the cockpit roll control 

must be moved suddenly and 

maintained so as to achieve a roll rate 

not less than one third of that obtained 

in paragraph (b). 

Issued in Renton, Washington, on February 

12, 2013. 

Ali Bahrami, 

Manager, Transport Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. 2013–03658 Filed 2–15–13; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 25 

[Docket No. FAA–2012–1246; Special 

Conditions No. 25–481–SC] 

Special Conditions: Embraer S.A., 

Model EMB–550 Airplane; Interaction 

of Systems and Structures 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final special conditions. 

SUMMARY: These special conditions are 

issued for the Embraer S.A. Model 

EMB–550 airplane. This airplane will 

have a novel or unusual design 

feature(s) associated with the interaction 

of systems and structures. 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: Effective date: March 21, 2013. 

FOR FURTHER INFORMATION CONTACT: 

Todd Martin, FAA, Airframe and Cabin 

Safety Branch, ANM–115, Transport 

Airplane Directorate, Aircraft 

Certification Service, 1601 Lind Avenue 

SW., Renton, Washington 98057–3356; 

telephone 425–227–1178; facsimile 

425–227–1232. 

SUPPLEMENTARY INFORMATION: 

Background 

On May 14, 2009, Embraer S.A. 

applied for a type certificate for their 

new Model EMB–550 airplane. The 

Model EMB–550 airplane is the first of 

a new family of jet airplanes designed 

for corporate flight, fractional, charter, 

and private owner operations. The 

aircraft has a conventional configuration 

with low wing and T-tail empennage. 

The primary structure is metal with 

composite empennage and control 

surfaces. The Model EMB–550 airplane 

is designed for 8 passengers, with a 

maximum of 12 passengers. It is 

equipped with two Honeywell 

HTF7500–E medium bypass ratio 

turbofan engines mounted on aft 

fuselage pylons. Each engine produces 

approximately 6,540 pounds of thrust 

for normal takeoff. The primary flight 

controls consist of hydraulically 

powered fly-by-wire elevators, aileron 

and rudder, controlled by the pilot or 

copilot sidestick. 

The Model Embraer EMB–550 

airplane is equipped with systems that, 

directly or as a result of failure or 

malfunction, affect its structural 

performance. Current regulations do not 

take into account loads for the airplane 

due to the effects of systems on 

structural performance including 

normal operation and failure conditions 

with strength levels related to 

probability of occurrence. Special 

conditions are needed to account for 

these features. 

Type Certification Basis 

Under the provisions of Title 14, Code 

of Federal Regulations (14 CFR) 21.17, 


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Embraer S.A. must show that the Model 

EMB–550 airplane meets the applicable 

provisions of part 25, as amended by 

Amendments 25–1 through 25–127 

thereto. 

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 EMB–550 airplane 

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 Embraer S.A. Model 

EMB–550 airplane must comply with 

the fuel vent and exhaust emission 

requirements of 14 CFR part 34 and the 

noise certification requirements of 14 

CFR part 36 and the FAA must issue a 

finding of regulatory adequacy under 

section 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 Embraer S.A. Model EMB–550 

airplane is equipped with systems that, 

directly or as a result of failure or 

malfunction, affect its structural 

performance. Current regulations do not 

take into account loads for the airplane 

due to the effects of systems on 

structural performance including 

normal operation and failure conditions 

with strength levels related to 

probability of occurrence. Special 

conditions are needed to account for 

these features. 

These special conditions define 

criteria to be used in the assessment of 

the effects of these systems on 

structures. The general approach of 

accounting for the effect of system 

failures on structural performance 

would be extended to include any 

system in which partial or complete 

failure, alone or in combination with 

other system partial or complete 

failures, would affect structural 

performance. 

Discussion 

These airplanes are equipped with 

systems that, directly or as a result of 

failure or malfunction, affect its 

structural performance. Current 

regulations do not take into account 

loads for the aircraft due to the effects 

of systems on structural performance 

including normal operation and failure 

conditions with strength levels related 

to probability of occurrence. These 

special conditions define criteria to be 

used in the assessment of the effects of 

these systems on structures. 

Special conditions have been applied 

on past airplane programs to require 

consideration of the effects of systems 

on structures. The regulatory authorities 

and industry developed standardized 

criteria in the Aviation Rulemaking 

Advisory Committee (ARAC) forum 

based on the criteria defined in 

Advisory Circular 25.672, Active Flight 

Controls, dated November 11, 1983. The 

ARAC recommendations have been 

incorporated in European Aviation 

Safety Agency (EASA) Certification 

Specifications (CS) 25.302 and CS 25 

Appendix K. FAA rulemaking on this 

subject is not complete, thus the need 

for the special conditions. 

The proposed special conditions are 

similar to those previously applied to 

other airplane models and to CS 25.302. 

The major differences between these 

proposed special conditions and the 

current CS 25.302 are as follows: 

1. Both these special conditions and 

CS 25.302 specify the design load 

conditions to be considered. In 

paragraphs 2(a)(1) and 2(b)(2)(i) of these 

special conditions, the special 

conditions clarify that, in some cases, 

different load conditions are to be 

considered due to other special 

conditions or equivalent level of safety 

findings. 

2. Paragraph 2(b)(2)(i) of these special 

conditions include the additional 

ground-handling conditions of 

§§ 25.493(d) and 25.503. These 

conditions are added in case the 

Embraer S.A. Model EMB–550 airplane 

has systems that affect braking and 

pivoting. 

3. Both CS 25.302 and paragraph 

(2)(d) of these special conditions allow 

consideration of the probability of being 

in a dispatched configuration when 

assessing subsequent failures and 

potential ‘‘continuation of flight’’ loads. 

However, these special conditions also 

allow using probability when assessing 

failures that induce loads at the ‘‘time 

of occurrence,’’ whereas CS 25.302 does 

not. 

Discussion of Comments 

Notice of proposed special conditions 

No. 25–12–16–SC for the Embraer S.A. 

Model EMB–550 airplanes was 

published in the Federal Register on 

November 28, 2012, (77 FR 70941). No 

comments were received, and the 

special conditions are adopted as 

proposed. 

Applicability 

As discussed above, these special 

conditions are applicable to the Embraer 

S.A. Model EMB–550 airplane. Should 

Embraer S.A. apply at a later date for a 

change to the type certificate to include 

another model incorporating the same 

novel or unusual design feature, the 

special conditions would apply to that 

model as well. 

Conclusion 

This action affects only certain novel 

or unusual design features on one model 

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, pursuant to the 

authority delegated to me by the 

Administrator, the following special 

conditions are issued as part of the type 

certification basis for Embraer S.A. 

Model EMB–550 airplanes to address 

the effects of systems on structures. 

1. General interaction of systems and 

structures. 

For airplanes equipped with systems 

that affect structural performance, either 

directly or as a result of a failure or 

malfunction, the influence of these 

systems and their failure conditions 

must be taken into account when 

showing compliance with the 

requirements of Title 14, Code of 

Federal Regulations (14 CFR) part 25 

subparts C and D. 

The following criteria must be used 

for showing compliance with these 

special conditions for airplanes 

equipped with flight control systems, 

autopilots, stability augmentation 

systems, load alleviation systems, fuel 

management systems, and other systems 

that either directly or as a result of 

failure or malfunction affect structural 

performance. If these special conditions 

are used for other systems, it may be 

necessary to adapt the criteria to the 

specific system. 


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(a) The criteria defined herein only 

address the direct structural 

consequences of the system responses 

and performances and cannot be 

considered in isolation but should be 

included in the overall safety evaluation 

of the airplane. These criteria may in 

some instances duplicate standards 

already established for this evaluation. 

These criteria are only applicable to 

structure in which failure could prevent 

continued safe flight and landing. 

Specific criteria that define acceptable 

limits on handling characteristics or 

stability requirements when operating 

in the system degraded or inoperative 

mode are not provided in these special 

conditions. 

(b) The following definitions are 

applicable to these special conditions. 

(1) Structural performance: Capability 

of the airplane to meet the structural 

requirements of 14 CFR part 25. 

(2) Flight limitations: Limitations that 

can be applied to the airplane flight 

conditions following an in-flight 

occurrence and that are included in the 

flight manual (e.g., speed limitations 

and avoidance of severe weather 

conditions). 

(3) Operational limitations: 

Limitations, including flight limitations, 

that can be applied to the airplane 

operating conditions before dispatch 

(e.g., fuel, payload, and Master 

Minimum Equipment List limitations). 

(4) Probabilistic terms: The 

probabilistic terms (i.e., probable, 

improbable, and extremely improbable) 

used in these special conditions are the 

same as those used in § 25.1309. 

(5) Failure condition: The term 

‘‘failure condition’’ is the same as that 

used in § 25.1309. However, these 

special conditions apply only to system 

failure conditions that affect the 

structural performance of the airplane 

(e.g., system failure conditions that 

induce loads, change the response of the 

airplane to inputs such as gusts or pilot 

actions, or lower flutter margins). 

2. Effect on Systems and Structures. 

The following criteria are used in 

determining the influence of a system 

and its failure conditions on the 

airplane structure. 

(a) System fully operative. With the 

system fully operative, the following 

apply: 

(1) Limit loads must be derived in all 

normal operating configurations of the 

system from all the limit conditions 

specified in Subpart C (or defined by 

special condition or equivalent level of 

safety in lieu of those specified in 

Subpart C), taking into account any 

special behavior of such a system or 

associated functions or any effect on the 

structural performance of the airplane 

that may occur up to the limit loads. In 

particular, any significant nonlinearity 

(rate of displacement of control surface, 

thresholds or any other system 

nonlinearities) must be accounted for in 

a realistic or conservative way when 

deriving limit loads from limit 

conditions. 

(2) The airplane must meet the 

strength requirements of part 25 (static 

strength, residual strength), using the 

specified factors to derive ultimate loads 

from the limit loads defined above. The 

effect of nonlinearities must be 

investigated beyond limit conditions to 

ensure the behavior of the system 

presents no anomaly compared to the 

behavior below limit conditions. 

However, conditions beyond limit 

conditions need not be considered when 

it can be shown that the airplane has 

design features that will not allow it to 

exceed those limit conditions. 

(3) The airplane must meet the 

aeroelastic stability requirements of 

§ 25.629. 

(b) System in the failure condition. 

For any system failure condition not 

shown to be extremely improbable, the 

following apply: 

(1) At the time of occurrence. Starting 

from 1-g level flight conditions, a 

realistic scenario, including pilot 

corrective actions, must be established 

to determine the loads occurring at the 

time of failure and immediately after 

failure. 

(i) For static strength substantiation, 

these loads, multiplied by an 

appropriate factor of safety that is 

related to the probability of occurrence 

of the failure, are ultimate loads to be 

considered for design. The factor of 

safety (FS) is defined in Figure 1. 

(ii) For residual strength 

substantiation, the airplane must be able 

to withstand two-thirds of the ultimate 

loads defined in paragraph 2(b)(1)(i) of 

these special conditions. For 

pressurized cabins, these loads must be 

combined with the normal operating 

differential pressure. 

(iii) Freedom from aeroelastic 

instability must be shown up to the 

speeds defined in § 25.629(b)(2). For 

failure conditions that result in speeds 

beyond VC/MC, freedom from 

aeroelastic instability must be shown to 

increased speeds, so that the margins 

intended by § 25.629(b)(2) are 

maintained. 

(iv) Failures of the system that result 

in forced structural vibrations (e.g., 

oscillatory failures) must not produce 

loads that could result in detrimental 

deformation of primary structure. 

(2) For the continuation of the flight. 

For the airplane, in the system failed 

state and considering any appropriate 

reconfiguration and flight limitations, 

the following apply: 

(i) The loads derived from the 

following conditions (or conditions 

defined by special conditions or 

equivalent level of safety in lieu of the 


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following special conditions) at speeds 

up to VC/MC, or the speed limitation 

prescribed for the remainder of the 

flight, must be determined: 

(A) The limit symmetrical 

maneuvering conditions specified in 

§§ 25.331 and 25.345. 

(B) The limit gust and turbulence 

conditions specified in §§ 25.341 and 

25.345. 

(C) The limit rolling conditions 

specified in § 25.349 and the limit 

unsymmetrical conditions specified in 

§§ 25.367, 25.427(b), and 25.427(c). 

(D) The limit yaw maneuvering 

conditions specified in § 25.351. 

(E) The limit ground loading 

conditions specified in §§ 25.473, 

25.491, 25.493(d) and 25.503. 

(ii) For static strength substantiation, 

each part of the structure must be able 

to withstand the loads in paragraph 

2(b)(2)(i) of these special conditions 

multiplied by a factor of safety 

depending on the probability of being in 

this failure state. The factor of safety 

(FS) is defined in Figure 2. 

Qj = (Tj)(Pj) where: 

Tj = Average time spent in failure condition 

j (in hours) 

Pj = Probability of occurrence of failure mode 

j (per hour) 

Note: If Pj is greater than 10¥3 per flight 

hour then a 1.5 factor of safety must be 

applied to all limit load conditions specified 

in Subpart C. 

(iii) For residual strength 

substantiation, the airplane must be able 

to withstand two-thirds of the ultimate 

loads defined in paragraph 2(b)(2)(ii) of 

the special conditions. For pressurized 

cabins, these loads must be combined 

with the normal operating differential 

pressure. 

(iv) If the loads induced by the failure 

condition have a significant effect on 

fatigue or damage tolerance then their 

effects must be taken into account. 

(v) Freedom from aeroelastic 

instability must be shown up to a speed 

determined from Figure 3. Flutter 

clearance speeds V′ and V′′ may be 

based on the speed limitation specified 

for the remainder of the flight using the 

margins defined by § 25.629(b). 

V′ = Clearance speed as defined by 

§ 25.629(b)(2). 

V′′ = Clearance speed as defined by 

§ 25.629(b)(1). 

Qj = (Tj)(Pj) where: 

Tj = Average time spent in failure condition 

j (in hours) 

Pj = Probability of occurrence of failure mode 

j (per hour) 

Note: If Pj is greater than 10¥3 per flight 

hour, then the flutter clearance speed must 

not be less than V′′. 

(vi) Freedom from aeroelastic 

instability must also be shown up to V′ 

in Figure 3 above, for any probable 

system failure condition combined with 

any damage required or selected for 

investigation by § 25.571(b). 

(3) Consideration of certain failure 

conditions may be required by other 

sections of 14 CFR part 25 regardless of 

calculated system reliability. Where 

analysis shows the probability of these 

failure conditions to be less than 10¥9, 

criteria other than those specified in this 

paragraph may be used for structural 

substantiation to show continued safe 

flight and landing. 

(c) Failure indications. For system 

failure detection and indication, the 

following apply: 

(1) The system must be checked for 

failure conditions, not extremely 

improbable, that degrade the structural 


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11560 Federal Register / Vol. 78, No. 33 / Tuesday, February 19, 2013 / Rules and Regulations 

capability below the level required by 

14 CFR part 25 or significantly reduce 

the reliability of the remaining system. 

As far as reasonably practicable, the 

flightcrew must be made aware of these 

failures before flight. Certain elements 

of the control system, such as 

mechanical and hydraulic components, 

may use special periodic inspections, 

and electronic components may use 

daily checks, in lieu of detection and 

indication systems to achieve the 

objective of this requirement. These 

certification maintenance requirements 

must be limited to components that are 

not readily detectable by normal 

detection and indication systems and 

where service history shows that 

inspections will provide an adequate 

level of safety. 

(2) The existence of any failure 

condition, not extremely improbable, 

during flight that could significantly 

affect the structural capability of the 

airplane and for which the associated 

reduction in airworthiness can be 

minimized by suitable flight limitations, 

must be signaled to the flightcrew. For 

example, failure conditions that result 

in a factor of safety between the airplane 

strength and the loads of Subpart C 

below 1.25, or flutter margins below V′′, 

must be signaled to the flightcrew 

during flight. 

(d) Dispatch with known failure 

conditions. If the airplane is to be 

dispatched in a known system failure 

condition that affects structural 

performance, or affects the reliability of 

the remaining system to maintain 

structural performance, then the 

provisions of these special conditions 

must be met, including the provisions of 

paragraph 2(a) for the dispatched 

condition, and paragraph 2(b) for 

subsequent failures. Expected 

operational limitations may be taken 

into account in establishing Pj as the 

probability of failure occurrence for 

determining the safety margin in Figure 

1 of these special conditions. Flight 

limitations and expected operational 

limitations may be taken into account in 

establishing Qj as the combined 

probability of being in the dispatched 

failure condition and the subsequent 

failure condition for the safety margins 

in Figures 2 and 3 of these special 

conditions. These limitations must be 

such that the probability of being in this 

combined failure state and then 

subsequently encountering limit load 

conditions is extremely improbable. No 

reduction in these safety margins is 

allowed if the subsequent system failure 

rate is greater than 10¥3 per hour. 

Issued in Renton, Washington, on February 

12, 2013. 

Ali Bahrami, 

Manager, Transport Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. 2013–03678 Filed 2–15–13; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 25 

[Docket No. FAA–2012–1218; Special 

Conditions No. 25–483–SC] 

Special Conditions: Embraer S.A., 

Model EMB–550 Airplane; Electronic 

Flight Control System: LateralDirectional and Longitudinal Stability 

and Low Energy Awareness 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final special conditions. 

SUMMARY: These special conditions are 

issued for the Embraer S.A. Model 

EMB–550 airplane. This airplane will 

have a novel or unusual design 

feature(s) associated with an electronic 

flight control system with respect to 

lateral-directional and longitudinal 

stability and low energy awareness. 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: Effective date: March 21, 2013. 

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: 

Background 

On May 14, 2009, Embraer S.A. 

applied for a type certificate for their 

new Model EMB–550 airplane. The 

Model EMB–550 airplane is the first of 

a new family of jet airplanes designed 

for corporate flight, fractional, charter, 

and private owner operations. The 

aircraft has a conventional configuration 

with low wing and T-tail empennage. 

The primary structure is metal with 

composite empennage and control 

surfaces. The Model EMB–550 airplane 

is designed for 8 passengers, with a 

maximum of 12 passengers. It is 

equipped with two Honeywell 

HTF7500–E medium bypass ratio 

turbofan engines mounted on aft 

fuselage pylons. Each engine produces 

approximately 6,540 pounds of thrust 

for normal takeoff. The primary flight 

controls consist of hydraulically 

powered fly-by-wire elevators, aileron 

and rudder, controlled by the pilot or 

copilot sidestick. 

The Embraer S.A. Model EMB–550 

airplane has a flight control design 

feature within the normal operational 

envelope in which sidestick deflection 

in the roll axis commands roll rate. As 

a result, the stick force in the roll axis 

will be zero (neutral stability) during the 

straight, steady sideslip flight maneuver 

required by Title 14, Code of Federal 

Regulations (14 CFR) 25.177(c) and will 

not be ‘‘substantially proportional to the 

angle of sideslip’’ as required by the 

rule. 

The longitudinal flight control laws 

for the Model EMB–550 airplane 

provide neutral static stability within 

the normal operational envelope; 

therefore, the airplane design does not 

comply with the static longitudinal 

stability requirements of §§ 25.171, 

25.173, and 25.175. 

Static longitudinal stability provides 

awareness to the flightcrew of a low 

energy state (i.e., low speed and thrust 

at low altitude). Recovery from a low 

energy state may become hazardous 

when associated with a low altitude and 

performance-limiting conditions. These 

low energy situations must therefore be 

avoided, and pilots must be given 

adequate cues when approaching such 

situations. 

Type Certification Basis 

Under the provisions of 14 CFR 21.17, 

Embraer S.A. must show that the Model 

EMB–550 airplane meets the applicable 

provisions of part 25, as amended by 

Amendments 25–1 through 25–127 

thereto. 

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 EMB–550 airplane 

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. 


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