49426 Federal Register / Vol. 79, No. 162 / Thursday, August 21, 2014 / Rules and Regulations 

Amendment 25–123 in the certification basis 

for Airbus Model A350–900 airplanes. These 

special conditions apply only to rechargeable 

lithium-ion batteries and battery systems and 

their installations. The requirements of 

§ 25.1353(b) at Amendment 25–123 remain in 

effect for batteries and battery installations 

on Airbus Model A350–900 airplanes that do 

not use rechargeable lithium-ion batteries. 

Issued in Renton, Washington, on July 30, 

2014. 

Jeffrey E. Duven, 

Manager, Transport Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. 2014–19821 Filed 8–20–14; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 25 

[Docket No. FAA–2013–0901; Special 

Conditions No. 25–536–SC] 

Special Conditions: Airbus Model 

A350–900 Airplanes; Flight-Envelope 

Protection: High-Speed Limiting 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final special conditions. 

SUMMARY: These special conditions are 

issued for Airbus Model A350–900 

series airplanes. These airplanes will 

have a novel or unusual design feature 

associated with high speed limiting. 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: September 22, 

2014. 

FOR FURTHER INFORMATION CONTACT: Joe 

Jacobsen, FAA, Airplane and Flightcrew 

Interface Branch, ANM–111, Transport 

Airplane Directorate, Aircraft 

Certification Service, 1601 Lind Avenue 

SW., Renton, Washington 98057–3356; 

telephone (425) 227–2011; facsimile 

(425) 227–1320. 

SUPPLEMENTARY INFORMATION: 

Background 

On August 25, 2008, Airbus applied 

for a type certificate for their new Model 

A350–900 airplane. Later, Airbus 

requested, and the FAA approved, an 

extension to the application for FAA 

type certification to November 15, 2009. 

The Model A350–900 airplane has a 

conventional layout with twin wingmounted Rolls-Royce Trent XWB 

engines. It features a twin-aisle, 9- 

abreast, economy-class layout, and 

accommodates side-by-side placement 

of LD–3 containers in the cargo 

compartment. The basic Model A350– 

900 airplane configuration 

accommodates 315 passengers in a 

standard two-class arrangement. The 

design cruise speed is Mach 0.85 with 

a maximum take-off weight of 602,000 

lbs. 

The longitudinal-control law design 

of the Airbus Model A350–900 airplane 

incorporates an overspeed protection 

system in the normal mode, which 

prevents the pilot from inadvertently or 

intentionally exceeding a speed 

approximately equivalent to VFC or 

attaining VDF. Current Title 14 Code of 

Federal Regulations (14 CFR) part 25 

sections do not relate to a high-speedlimiting protection system that might 

preclude or modify flying-qualities 

assessments in the overspeed region. 

However, the requirements of § 25.253 

(high-speed characteristics) and its 

related policy are applicable to the 

Model A350–900 airplane and are not 

affected by this special condition. 

Type Certification Basis 

Under 14 CFR 21.17, Airbus must 

show that the Model A350–900 airplane 

meets 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 Airbus Model A350–900 airplane 

because of a novel or unusual design 

feature, special conditions are 

prescribed under § 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 A350–900 

airplane must comply with the fuel-vent 

and exhaust-emission requirements of 

14 CFR part 34, and the noisecertification requirements of 14 CFR 

part 36. 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, under § 11.38, 

and they become part of the typecertification basis under § 21.17(a)(2). 

Novel or Unusual Design Features 

The Model A350–900 airplane 

incorporates the following novel or 

unusual design features: an overspeed 

protection system that prevents the pilot 

from inadvertently or intentionally 

exceeding a speed approximately 

equivalent to VFC, or attaining VDF. 

At VMO + 10 knots or MMO + 0.02 

knots, an automatic nose-up pitch is 

applied with phase advance in the event 

of high acceleration. The speed 

stabilizes at VD-10kts/MD-0.02 if the 

stick is full forward, or the speed will 

return below VMO/MMO if the stick is 

released. 

Discussion 

This special condition establishes 

requirements to ensure that operation of 

the high-speed-limiting protection 

system does not impede normal 

attainment of speeds up to the 

overspeed warning. Its main features 

are: 

1. It protects the airplane against highspeed/high Mach-number flight 

conditions beyond VMO/MMO. 

2. It does not interfere with flight at 

VMO/MMO, even in turbulent air. 

3. It still provides load-factor 

limitation through the ‘‘pitch limiting’’ 

function described below. 

4. It restores positive static stability 

beyond VMO/MMO. 

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. 25–13–23–SC for the Airbus Model 

A350–900 airplane was published in the 

Federal Register on January 8, 2014 (79 

FR 1336). An anonymous comment was 

received January 16, 2014. The 

commenter was concerned about highlevel windshears, and the potential 

violation of Reduced Vertical Separation 

Minimums (RVSM) airspace restrictions 

that might accompany a nose-up input 

of a high-speed protection system. In 

addition, the commenter was concerned 

about system failures or malfunctions 

leading to unintended control 

consequences and the pilot’s ability to 

appropriately counteract those control 

anomalies. 

The FAA would like to clarify that 

this special condition only addresses 

one aspect of high-speed limiting 

designs. Many other regulations, such as 

14 CFR 25.1301 and 25.1309, address 

the proper intended function and failure 

scenarios of such a system. Therefore, 


tkelley on DSK3SPTVN1PROD with RULES
Federal Register / Vol. 79, No. 162 / Thursday, August 21, 2014 / Rules and Regulations 49427 

the anonymous comment is beyond the 

scope of this special condition, and is 

already accounted for and considered in 

the basic regulatory-compliance process. 

Applicability 

As discussed above, these special 

conditions apply to Airbus Model 

A350–900 airplanes. Should Airbus 

apply later 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 Airbus 

Model A350–900 series 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 Airbus Model A350–900 series 

airplanes. 

In addition to § 25.143, the following 

requirements apply: Operation of the 

high-speed limiter during all routine 

and descent-procedure flight must not 

impede normal attainment of speeds up 

to overspeed warning. 

Issued in Renton, Washington, on August 

15, 2014. 

Jeffrey E. Duven, 

Manager, Transport Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. 2014–19822 Filed 8–20–14; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 25 

[Docket No. FAA–2013–1001; Special 

Conditions No. 25–535–SC] 

Special Conditions: Airbus Model 

A350–900 Airplanes; High-Speed 

Protection System 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final special conditions. 

SUMMARY: These special conditions are 

issued for Airbus Model A350–900 

airplanes. These airplanes will have a 

novel or unusual design feature 

associated with a high-speed protection 

system that limits nose-down pilot 

authority at speeds above VC/MC, and 

prevents the airplane from performing 

the maneuver required under the Code 

of Federal Regulations. 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: September 22, 

2014. 

FOR FURTHER INFORMATION CONTACT: 

Todd Martin, FAA, Airframe/Cabin 

Safety, ANM–115, Transport Airplane 

Directorate, Aircraft Certification 

Service, 1601 Lind Avenue SW., 

Renton, Washington 98057–3356; 

telephone (425) 227–1178; facsimile 

(425) 227–1322. 

SUPPLEMENTARY INFORMATION: 

Background 

On August 25, 2008, Airbus applied 

for a type certificate for their new Model 

A350–900 airplane. Later, Airbus 

requested, and the FAA approved, an 

extension to the application for FAA 

type certification to November 15, 2009. 

The Model A350–900 airplane has a 

conventional layout with twin wingmounted Rolls-Royce Trent XWB 

engines. It features a twin-aisle, 9- 

abreast, economy-class layout, and 

accommodates side-by-side placement 

of LD–3 containers in the cargo 

compartment. The basic Model A350– 

900 airplane configuration 

accommodates 315 passengers in a 

standard two-class arrangement. The 

design cruise speed is Mach 0.85 with 

a maximum take-off weight of 602,000 

lbs. 

The Model A350–900 airplane, like 

Airbus Model A320, A330, A340 and 

A380 series airplanes, has a high-speed 

protection system that limits nose-down 

pilot authority at speeds above VC/MC, 

and prevents the airplane from actually 

performing the maneuver required 

under § 25.335(b)(1). Special conditions 

are necessary to address the Model 

A350–900 airplane high-speed 

protection system. These special 

conditions identify various symmetric 

and non-symmetric maneuvers that will 

ensure that an appropriate design dive 

speed, VD/MD, is established. 

Type Certification Basis 

Under Title 14, Code of Federal 

Regulations (14 CFR) 21.17, Airbus must 

show that the Model A350–900 airplane 

meets 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 A350–900 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 Model A350–900 

airplane must comply with the fuel-vent 

and exhaust-emission requirements of 

14 CFR part 34, and the noisecertification requirements of 14 CFR 

part 36. 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, under § 11.38, 

and they become part of the typecertification basis under § 21.17(a)(2). 

Novel or Unusual Design Features 

In addition to the applicable 

airworthiness regulations and special 

conditions, the Model A350–900 

airplane must comply with the fuel-vent 

and exhaust-emission requirements of 

14 CFR part 34, and the noisecertification requirements of 14 CFR 

part 36. The FAA must issue a finding 

of regulatory adequacy under § 611 of 

Public Law 92–574, the ‘‘Noise Control 

Act of 1972.’’ 

The Airbus Model A350–900 airplane 

will incorporate the following novel or 

unusual design features: 

A high-speed protection system that 

limits nose-down pilot authority at 

speeds above VC/MC, and prevents the 

airplane from actually performing the 

maneuver required under § 25.335(b)(1). 

The special conditions identify various 

symmetric and non-symmetric 

maneuvers that will ensure that an 

appropriate design dive speed, VD/MD, 

is established. 

Discussion 

Section 25.335(b)(1) is an analytical 

envelope condition originally adopted 

in Part 4b of the Civil Air Regulations 

to provide an acceptable speed margin 


tkelley on DSK3SPTVN1PROD with RULES