66888 Federal Register / Vol. 71, No. 222 / Friday, November 17, 2006 / Proposed Rules 

Done in Washington, DC, this 14th day of 

November 2006. 

Kevin Shea, 

Acting Administrator, Animal and Plant 

Health Inspection Service. 

[FR Doc. E6–19452 Filed 11–16–06; 8:45 am] 

BILLING CODE 3410–34–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 33 

[Docket No. NE127; Notice No. 33–06–01–

SC] 

Special Conditions: General Electric 

Company GEnx Model Turbofan 

Engines 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Notice of proposed special 

conditions. 

SUMMARY: This action proposes special 

conditions for General Electric 

Company (GE) GEnx turbofan engine 

models. These engines will have a novel 

or unusual design feature associated 

with the fan blades. The Administrator 

has determined that the applicable part 

33 airworthiness regulations do not 

contain adequate or appropriate safety 

standards for this design feature. These 

proposed special conditions contain the 

added safety standards that the 

Administrator considers necessary to 

establish a level of safety equivalent to 

that established by the airworthiness 

regulations. 

EFFECTIVE DATES: We must receive your 

comments by December 18, 2006. 

ADDRESSES: You may mail two copies of 

your comments to: Federal Aviation 

Administration, Engine and Propeller 

Directorate, Attn: Robert McCabe, Rules 

Docket (ANE–111), Docket No. NE127, 

12 New England Executive Park, 

Burlington, Massachusetts 01803–5299. 

You may deliver two copies to the 

Engine and Propeller Directorate at the 

above address. You must mark your 

comments: Docket No. NE127. You may 

send comments via email to 

robert.mccabe@faa.gov. You must use 

the subject ‘‘Docket No. NE127’’. You 

can inspect comments in the Rules 

Docket weekdays, except Federal 

holidays, between 7:30 a.m. and 4 p.m. 

FOR FURTHER INFORMATION CONTACT: 

Robert McCabe, ANE–111, Rulemaking 

and Policy Branch, Engine and Propeller 

Directorate, Aircraft Certification 

Service, 12 New England Executive 

Park, Burlington, Massachusetts 01803–

5299; telephone (781) 237–7138; 

facsimile (781) 238–7199; email 

robert.mccabe@faa.gov. 

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 special 

conditions, explain the reason for any 

recommended change, and include 

supporting data. We ask that you send 

us two copies of written comments. 

We will file in the docket all 

comments we receive, as well as a 

report summarizing each substantive 

public contact with FAA personnel 

about these special conditions. You can 

inspect the docket before and after the 

comment closing date. If you wish to 

review the docket in person, go to the 

address in the ADDRESSES section of this 

preamble between 9 a.m. and 5 p.m., 

Monday through Friday, except Federal 

holidays. 

We will consider all comments we 

receive by the closing date for 

comments. We will consider comments 

filed late if it is possible to do so 

without incurring expense or delay. We 

may change these special conditions 

based on the comments we receive. 

If you want us to let you know we 

received your comments on this 

proposal, send us a pre-addressed, 

stamped postcard on which the docket 

number appears. We will stamp the date 

on the postcard and mail it back to you. 

Background 

On December 13, 2004, the General 

Electric Company (GE) applied to the 

FAA for a new type certificate for the 

GEnx series engine models. On May 24, 

2005, GE submitted a revised 

application for a type certificate that 

added models and changed the model 

designation nomenclature. The turbofan 

engine models to be certified are GEnx–

1B54, GEnx–1B58, GEnx–1B64, GEnx–

1B67, GEnx–1B70, GEnx–1B70/72, 

GEnx–1B70/75, GEnx–1B72, and GEnx–

1B75. For these GEnx engine models, 

GE plans to use carbon graphite 

composite fan blades incorporating 

metal leading and trailing edges that use 

geometry, composite structural 

materials, and manufacturing methods 

very similar to those used for the 

previously certified GE90-series engine 

fan blades designs. 

In lieu of direct compliance to 

§ 33.94(a)(1) for the GEnx fan blades, the 

FAA has proposed that GE comply with 

new special conditions that retain the 

requirements of the original SC–33–

ANE–08 created for the GE90–76B, 

–77B, –85B, –90B, –94B model 

certification program, and then 

successfully applied to the GE90–

110B1, –113B, and –115B model 

certification program. 

These GE90 series engine model fan 

blades are manufactured using carbon 

graphite composite material that also 

incorporates metal leading and trailing 

edges. These unusual and novel design 

features result in the fan blades having 

significant differences in material 

property characteristics when compared 

to conventionally designed fan blades 

using non-composite metallic materials. 

GE submitted data and analysis during 

the GE90–76B, –77B, –85B, –90B, –94B 

model certification program showing 

the likelihood that a composite fan 

blade with fail below the inner annulus 

flow path line is highly improbable. GE, 

therefore, questioned the 

appropriateness of the requirement 

contained in § 33.94(a)(1) to show blade 

containment after a failure of the blade 

at the outermost retention feature. 

The FAA determined that the 

requirements of § 33.94(a)(1) are based 

on metallic blade characteristics and 

service history, and were not 

appropriate for the unusual design 

features of the composite fan blade 

design planned for the GE90–76B, –77B, 

–85B, –90B, –94B model turbofan 

engines. The FAA determined that a 

more realistic blade retention test would 

be achieved with a fan blade failure at 

the inner annulus flow path line (the 

complete airfoil only) instead of the 

outermost blade retention feature as 

currently required by § 33.94(a)(1). 

The FAA, therefore, issued special 

conditions SC–33–ANE–88 on February 

1, 1995 for the GE90–76B, –77B, –85B, 

–90B, –94B engine models. These 

special conditions defined additional 

safety standards for the carbon graphite 

composite fan blades that were 

appropriate for the unusual design 

features of those fan blades and that 

were determined to be necessary to 

establish a level of safety equivalent to 

that established by the airworthiness 

standards of § 33.94(a)(1). The FAA later 

determined that these special conditions 

continued to be appropriate for the 

amended type certificate applied to the 

GE90–110B1, –113B, and –115B engine 

models. 

The FAA also determined that the 

composite fan blade design and 

construction presents factors other than 

the expected location of a blade failure 

that must be considered. Tests and 

analyses must account for the effects of 

in-service deterioration of, 

manufacturing and materials variations 

in, and environmental effects on, the 

composite material. Tests and analyses 


jlentini on PROD1PC65 with PROPOSAL
Federal Register / Vol. 71, No. 222 / Friday, November 17, 2006 / Proposed Rules 66889 

must also show that a lightning strike on 

a composite fan blade will not result in 

a hazardous condition to the aircraft and 

that the engine will continue to meet the 

requirements of § 33.75. 

Therefore, due to the close similarity 

of the GEnx model series fan blade 

design to the previously certified GE90 

model series fan blade design, the FAA 

is proposing to issue similar special 

conditions as part of the type 

certification basis for the GEnx engine 

models in lieu of direct compliance to 

§ 33.94(a)(1). These special conditions 

define the additional requirements that 

the Administrator considers necessary 

to establish a level of safety equivalent 

to that which would be established by 

direct compliance to the airworthiness 

standards of § 33.94(a)(1). 

Type Certification Basis 

Under 14 CFR 21.17, GE must show 

that the GEnx series turbofan engine 

models meet the requirements of the 

applicable provisions of § 21.21 and part 

33. The FAA has determined that the 

applicable airworthiness regulations in 

part 33 do not contain adequate or 

appropriate safety standards for the 

GEnx series turbofan engine models 

because of its novel and unusual fan 

blade design features. Therefore, these 

special conditions are prescribed under 

the provisions of 14 CFR 11.19 and 

§ 21.16, and will become part of the type 

certification basis of the GEnx engine in 

accordance with 14 CFR 21.17(a)(2). 

As discussed above, these special 

conditions apply only to the GEnx series 

turbofan engine models. If the type 

certificate for those models is amended 

later to include any other models that 

incorporate the same novel or unusual 

design features, these special conditions 

would also apply to the other models 

under the provisions of 14 CFR 

21.101(a)(1). 

Novel or Unusual Design Features 

The GEnx–1B54, –1B58, –1B64, 

–1B67, –70B, –1B70/72, –1B70/75, –72B 

and –75B engine models will 

incorporate the following novel or 

unusual design features: fan blades to be 

manufactured using carbon graphite 

composite material that incorporates 

metal leading and training edges. 

Applicability 

As discussed above, these special 

conditions apply only to the GEnx–

1B54, –1B58, –1B64, –1B67, –70B, 

–1B70/72, –1B70/75, –72B and –75B 

turbofan engine models. If GE applies 

later for a change to the type certificate 

to include another model incorporating 

the same novel or unusual fan blade 

design features, these special conditions 

would apply to that model as well. 

Conclusion 

This action affects only the carbon 

fiber composite fan blade design 

features on the GEnx series turbofan 

engine models. It is not a rule of general 

applicability, and it affects only the 

General Electric Company which has 

applied to the FAA for certification of 

these fan blade design features. 

List of Subjects in 14 CFR Part 33 

Air transportation, Aircraft, Aviation 

safety, Safety. 

The authority citation for these 

special conditions continues to read 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 the GEnx 

series turbofan engines. 

1. In lieu of the fan blade containment 

test with the fan blade failing at the 

outermost retention groove as specified 

in § 33.94(a)(1), complete the following 

requirements: 

(a) Conduct an engine fan blade 

containment test with the fan blade 

failing at the inner annulus flow path 

line. 

(b) Substantiate by test and analyses, 

or other methods acceptable to the 

Administrator, that a minimum material 

properties fan disk and fan blade 

retention system can withstand without 

failure a centrifugal load equal to two 

times the maximum load which the 

retention system could experience 

within approved engine operating 

limitations. The fan blade retention 

system includes the portion of the fan 

blade from the inner annulus flow path 

line inward to the blade dovetail, the 

blade retention components, and the fan 

disk and fan blade attachment features. 

(c) Using a procedure approved by the 

Administrator, establish an operating 

limitation that specifies the maximum 

allowable number of start-stop stress 

cycles for the fan blade retention 

systems. The life evaluation shall 

include the combined effects of high 

cycle and low cycle fatigue. If the 

operating limitation is less than 100,000 

cycles, that limitation must be specified 

in Chapter 5 of the Engine Manual 

Airworthiness Limitation Section. 

(d) Substantiate that, during the 

service life of the engine, the total 

probability of the occurrence of a 

hazardous engine effect defined in 

§ 33.75 due to an individual blade 

retention system failure resulting from 

all possible causes will be extremely 

improbable, with a cumulative 

calculated probability of failure of less 

than 10¥9 per engine flight hour. 

(e) Substantiate by test or analysis that 

not only will the engine continue to 

meet the requirements of § 33.75 

following a lightning strike on the 

composite fan blade structure, but that 

the lightning strike will also not cause 

damage to the fan blades that would 

prevent continued safe operation of the 

affected engine. 

(f) Account for the effects of in-service 

deterioration, manufacturing variations, 

minimum material properties, and 

environmental effects during the tests 

and analyses required by paragraphs (a), 

(b), (c), (d), and (e) of these special 

conditions. 

(g) Propose fleet leader monitoring 

and field sampling programs for the 

GEnx engine fan blades that will 

monitor the effects of usage on fan blade 

and retention system integrity. The 

sampling program should use the 

experience gained on current GE90 

engine model monitoring programs, and 

must be approved by the FAA prior to 

certification of the GEnx engine models. 

Issued in Burlington, Massachusetts on 

November 7, 2006. 

Francis A. Favara, 

Manager, Engine and Propeller Directorate, 

Aircraft Certification Service. 

[FR Doc. 06–9230 Filed 11–16–06; 8:45 am] 

BILLING CODE 4910–13–M 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2006–26166; Directorate 

Identifier 2006–CE–58–AD] 

RIN 2120–AA64 

Airworthiness Directives; EADS 

SOCATA Model TBM 700 Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), Department of 

Transportation (DOT). 

ACTION: Notice of proposed rulemaking 

(NPRM). 

SUMMARY: We propose to adopt a new 

airworthiness directive (AD) for the 

products listed above. This proposed 

AD results from mandatory continuing 

airworthiness information (MCAI) 

issued by an aviation authority of 

another country to identify and correct 

an unsafe condition on an aviation 

product. The MCAI describes the unsafe 

condition as cracks on a vertical 


jlentini on PROD1PC65 with PROPOSAL