Federal Register / Vol. 78, No. 218 / Tuesday, November 12, 2013 / Proposed Rules 67323 

gravity. Nose gear loads, as well as 

airframe loads, must be determined. The 

airplane must support these loads as 

described in § 25.305. 

In addition to the above airworthiness 

standards, fatigue loads must also be 

determined and applied in accordance 

to § 25.571. 

Issued in Renton, Washington, on 

November 1, 2013. 

Jeffrey E. Duven, 

Acting Manager, Transport Airplane 

Directorate, Aircraft Certification Service. 

[FR Doc. 2013–26936 Filed 11–8–13; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 25 

[Docket No. FAA–2013–0897; Notice No. 25– 

13–29–SC] 

Special Conditions: Airbus, Model 

A350–900 Series Airplane; Transient 

Engine Failure Loads 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Notice of proposed special 

conditions. 

SUMMARY: This action proposes special 

conditions for Airbus Model A350–900 

series airplanes. These airplanes will 

have a novel or unusual design feature 

associated with the new generation of 

high bypass engines and the potential 

loads resulting from extreme engine 

failure conditions. 

The applicable airworthiness 

regulations do not contain adequate or 

appropriate safety standards for this 

design feature. These proposed 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: Send your comments on or 

before December 27, 2013. 

ADDRESSES: Send comments identified 

by docket number FAA–2013–0897 

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 the 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: 

Todd Martin, FAA, International 

Branch, ANM–115, Transport Airplane 

Directorate, Aircraft Certification 

Service, 1601 Lind Avenue SW., 

Renton, Washington 98057–3356; 

telephone (425) 227–1178; facsimile 

(425) 227–1320. 

SUPPLEMENTARY INFORMATION: 

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 proposed special 

conditions, explain the reason for any 

recommended change, and include 

supporting data. 

We will consider all comments we 

receive on or before the closing date for 

comments. We may change these special 

conditions based on the comments we 

receive. 

Background 

On August 25, 2008, Airbus applied 

for a type certificate for their new Model 

A350–900 series airplane. Later, Airbus 

requested and the FAA approved an 

extension to the application for FAA 

type certification to June 28, 2009. The 

Model A350–900 series has a 

conventional layout with twin wingmounted Rolls-Royce Trent engines. It 

features a twin aisle 9-abreast economy 

class layout, and accommodates side-byside placement of LD–3 containers in 

the cargo compartment. The basic 

Model A350–900 series configuration 

will accommodate 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. Airbus proposes the Model A350– 

900 series to be certified for extended 

operations (ETOPS) beyond 180 minutes 

at entry into service for up to a 420- 

minute maximum diversion time. 

The existing regulations are 

inadequate because the new, large 

bypass fan engines of the Model A350– 

900 series airplanes can cause more 

damage in a failure event than the 

previous engines. To maintain the level 

of safety envisioned by Title 14, Code of 

Federal Regulations (14 CFR) 25.61(b), 

more comprehensive criteria are needed 

for the new generation of high bypass 

engines. The more severe events 

resulting from extreme engine failure 

conditions would be treated as dynamic 

load conditions. The proposed special 

conditions would distinguish between 

the more common engine failure events 

and those rare events resulting from 

structural failures. The more common 

events would continue to be treated as 

static torque limit load conditions. The 

severe events would be considered 

ultimate loads, and include all transient 

loads associated with the event. An 

additional safety factor would be 

applied to the more critical airframe 

supporting structure. 

Type Certification Basis 

Under Title 14, Code of Federal 

Regulations (14 CFR) 21.17, Airbus must 

show that the Model A350–900 series 

meets the applicable provisions of 14 

CFR part 25, as amended by 

Amendments 25–1 through 25–128. 

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 series 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 proposed 

special conditions would also apply to 

the other model under § 21.101. 

In addition to the applicable 

airworthiness regulations and proposed 

special conditions, the Model A350–900 

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67324 Federal Register / Vol. 78, No. 218 / Tuesday, November 12, 2013 / Proposed Rules 

series 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, 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 series airplane 

will incorporate the following novel or 

unusual design features: Engines with 

large, bypass fans capable of producing 

much higher failure loads than previous 

engines. The Model A350–900 will 

therefore require additional dynamic 

loads analyses to assess the most severe 

engine failure events. The loads 

resulting from these conditions would 

be considered as ultimate loads, with an 

additional safety factor applied to the 

airframe supporting structure. 

Discussion 

The size, configuration, and failure 

modes of jet engines has changed 

considerably from those envisioned by 

Title 14 Code of Federal Regulations (14 

CFR) 25.361(b) when the engine seizure 

requirement was first adopted. Engines 

have become larger and are now 

designed with large bypass fans capable 

of producing much higher failure loads. 

Relative to the engine configurations 

that existed when the rule was 

developed in 1957, the present 

generation of engines are sufficiently 

different and novel to justify special 

conditions for Model A350–900 series 

airplanes. Service history has shown 

that the engine failure events that tend 

to cause the most severe loads are fan 

blade failures and these events occur 

much less frequently than the typical 

‘‘limit’’ load condition. 

The regulatory authorities and 

industry developed a standardized 

requirement in the Aviation Rulemaking 

Advisory Committee (ARAC) forum. 

The technical aspects of this 

requirement have been agreed and have 

been accepted by the ARAC Loads and 

Dynamics Harmonization Working 

Group. The proposed special condition 

reflects the ARAC recommendation and 

is essentially harmonized with the 

corresponding EASA Certification 

Specifications (CS) 25. In addition, the 

ARAC recommendation includes 

corresponding advisory material that is 

incorporated in CS–25. This advisory 

material is considered an acceptable 

means of compliance to the proposed 

special conditions. 

Applicability 

As discussed above, these proposed 

special conditions apply to the Airbus 

Model A350–900 series 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 proposed 

special conditions would apply to that 

model as well. 

Conclusion 

This action affects only certain novel 

or unusual design features on the 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 

proposed special conditions is as 

follows: 

Authority: 49 U.S.C. 106(g), 40113, 44701, 

44702, 44704. 

The Proposed Special Conditions 

Accordingly, the Federal Aviation 

Administration (FAA) proposes the 

following special conditions as part of 

the type certification basis for Airbus 

Model A350–900 series airplanes. 

In lieu of § 25.361(b) the following 

special condition is proposed: 

1. For turbine engine installations, the 

engine mounts, pylons, and adjacent 

supporting airframe structure must be 

designed to withstand 1g level flight 

loads acting simultaneously with the 

maximum limit torque loads imposed 

by each of the following: 

a. sudden engine deceleration due to 

a malfunction that could result in a 

temporary loss of power or thrust, 

b. the maximum acceleration of the 

engine. 

2. For auxiliary power unit 

installations, the power unit mounts 

and adjacent supporting airframe 

structure must be designed to withstand 

1g level flight loads acting 

simultaneously with the maximum limit 

torque loads imposed by each of the 

following: 

a. sudden auxiliary power unit 

deceleration due to malfunction or 

structural failure; and 

b. the maximum acceleration of the 

power unit. 

3. For engine supporting structure, an 

ultimate loading condition must be 

considered that combines 1g flight loads 

with the transient dynamic loads 

resulting from: 

a. the loss of any fan, compressor, or 

turbine blade; and separately 

b. where applicable to a specific 

engine design, any other engine 

structural failure that results in higher 

loads. 

4. The ultimate loads developed from 

the conditions specified in paragraphs 

3.a. and 3.b. are to be multiplied by a 

factor of 1.0 when applied to engine 

mounts and pylons and multiplied by a 

factor of 1.25 when applied to adjacent 

supporting airframe structure. 

5. The airplane must be capable of 

continued safe flight considering the 

aerodynamic effects on controllability 

due to any permanent deformation that 

results from the conditions specified in 

3. 

Issued in Renton, Washington, on October 

22, 2013. 

Stephen P. Boyd, 

Acting Manager, Transport Airplane 

Directorate, Aircraft Certification Service. 

[FR Doc. 2013–26911 Filed 11–8–13; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 71 

[Docket No. FAA–2013–0174; Airspace 

Docket No. 13–AGL–10] 

Proposed Amendment of Class E 

Airspace; Lapeer, MI 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Notice of proposed rulemaking 

(NPRM). 

SUMMARY: This action proposes to 

amend Class E airspace at Lapeer, MI. 

Additional controlled airspace is 

necessary to accommodate amended 

Standard Instrument Approach 

Procedures (SIAP) at Dupont—Lapeer 

Airport. The FAA is taking this action 

to enhance the safety and management 

of Instrument Flight Rules (IFR) 

operations for SIAPs at the airport. 

Geographic coordinates would also be 

updated. 

DATES: Comments must be received on 

or before December 27, 2013. 

ADDRESSES: Send comments on this 

proposal to the U.S. Department of 

Transportation, Docket Operations, 1200 

New Jersey Avenue SE., West Building 

Ground Floor, Room W12–140, 

Washington, DC 20590–0001. You must 

identify the docket number FAA–2013– 

0174/Airspace Docket No. 13–AGL–10, 

at the beginning of your comments. You 

may also submit comments through the 

Internet at http://www.regulations.gov. 

You may review the public docket 

containing the proposal, any comments 

received, and any final disposition in 

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