41810 Federal Register / Vol. 74, No. 159 / Wednesday, August 19, 2009 / Proposed Rules 

Branch, ANM–116, Transport Airplane 

Directorate, FAA, has the authority to 

approve AMOCs for this AD, if requested 

using the procedures found in 14 CFR 39.19. 

Send information to ATTN: Sanjay Ralhan, 

Aerospace Engineer, International Branch, 

ANM–116, Transport Airplane Directorate, 

FAA, 1601 Lind Avenue, SW., Renton, 

Washington 98057–3356; telephone (425) 

227–1405; fax (425) 227–1149. Before using 

any approved AMOC on any airplane to 

which the AMOC applies, notify your 

appropriate principal inspector (PI) in the 

FAA Flight Standards District Office (FSDO), 

or lacking a PI, your local FSDO. 

(2) Airworthy Product: For any 

requirement in this AD to obtain corrective 

actions from a manufacturer or other source, 

use these actions if they are FAA-approved. 

Corrective actions are considered FAAapproved if they are approved by the State 

of Design Authority (or their delegated 

agent). You are required to assure the product 

is airworthy before it is returned to service. 

(3) Reporting Requirements: For any 

reporting requirement in this AD, under the 

provisions of the Paperwork Reduction Act, 

the Office of Management and Budget (OMB) 

has approved the information collection 

requirements and has assigned OMB Control 

Number 2120–0056. 

(4) Special Flight Permits: Special flight 

permits may be issued in accordance with 

sections 21.197 and 21.199 of the Federal 

Aviation Regulations (14 CFR 21.197 and 

21.199) to operate the airplane to a location 

where the airplane can be modified (if the 

operator elects to do so), except if two or 

more center mounting rods or rod ends are 

heavily corroded or broken, a special flight 

permit is not permitted. 

Related Information 

(h) Refer to MCAI Brazilian Airworthiness 

Directive 2008–10–02, dated October 21, 

2008; Embraer Service Bulletin 145–49–0034, 

Revision 01, dated September 8, 2008; and 

Embraer Service Bulletin 145LEG–49–0008, 

Revision 02, dated September 8, 2008, for 

related information. 

Issued in Renton, Washington, on August 

7, 2009. 

Stephen P. Boyd, 

Acting Manager, Transport Airplane 

Directorate, Aircraft Certification Service. 

[FR Doc. E9–19852 Filed 8–18–09; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2009–0714; Directorate 

Identifier 2009–NM–041–AD] 

RIN 2120–AA64 

Airworthiness Directives; Empresa 

Brasileira de Aeronautica S.A. 

(EMBRAER) Model EMB–135BJ, 

–135ER, –135KE, –135KL, –135LR, 

–145, –145EP, 145ER, –145MP, 

–145MR, –145XR, and 145LR Airplanes 

Modified in Accordance With Brazilian 

Supplemental Type Certificate (STC) 

2002S06–09, 2002S06–10, or 2003S08– 

01 

AGENCY: Federal Aviation 

Administration (FAA), 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) 

originated 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: It was reported that after 

commanding the landing gear lever to 

down the three green landing gear 

positioning indication was displayed 

followed by the LG/LEVER DISAGREE 

EICAS [engine indicating and crew 

alerting system] message. The crew 

decided to continue the approach and 

landing procedure. As soon as the crew 

identified that the landing gear was not 

extended properly, a go-around 

procedure was successfully performed. 

During maneuver, the airplane settled 

momentarily onto the flaps and belly. 

The unsafe condition is the landing 

gear remaining in the up and locked 

position during approach and landing 

and accompanied by an invalid EICAS 

landing gear position indication, which 

could result in landing with gear in the 

up position, and eliminate 

controllability of the airplane on 

ground. This may consequently result in 

structural damage to the airplane. The 

proposed AD would require actions that 

are intended to address the unsafe 

condition described in the MCAI. 

DATES: We must receive comments on 

this proposed AD by September 18, 

2009. 

ADDRESSES: You may send comments by 

any of the following methods: 

• Federal eRulemaking Portal: Go to 

http://www.regulations.gov. Follow the 

instructions for submitting comments. 

• Fax: (202) 493–2251. 

• Mail: U.S. Department of 

Transportation, Docket Operations, M– 

30, West Building Ground Floor, Room 

W12–140, 1200 New Jersey Avenue, SE., 

Washington, DC 20590. 

• Hand Delivery: U.S. Department of 

Transportation, Docket Operations, M– 

30, West Building Ground Floor, Room 

W12–40, 1200 New Jersey Avenue, SE., 

Washington, DC, between 9 a.m. and 5 

p.m., Monday through Friday, except 

Federal holidays. 

For service information identified in 

this proposed AD, contact Empresa 

Brasileira de Aeronautica S.A. 

(EMBRAER), Technical Publications 

Section (PC 060), Av. Brigadeiro Faria 

Lima, 2170—Putim—12227–901 Sa ̃o 

Jose dos Campos—SP—BRASIL; 

telephone: +55 12 3927–5852 or +55 12 

3309–0732; fax: +55 12 3927–7546; email: distrib@embraer.com.br; Internet: 

http://www.flyembraer.com. You may 

review copies of the referenced service 

information at the FAA, Transport 

Airplane Directorate, 1601 Lind Avenue 

SW., Renton, Washington. For 

information on the availability of this 

material at the FAA, call 425–227–1221 

or 425–227–1152. 

Examining the AD Docket 

You may examine the AD docket on 

the Internet at http:// 

www.regulations.gov; or in person at the 

Docket Operations office between 9 a.m. 

and 5 p.m., Monday through Friday, 

except Federal holidays. The AD docket 

contains this proposed AD, the 

regulatory evaluation, any comments 

received, and other information. The 

street address for the Docket Operations 

office (telephone (800) 647–5527) is in 

the ADDRESSES section. Comments will 

be available in the AD docket shortly 

after receipt. 

FOR FURTHER INFORMATION CONTACT: 

Sanjay Ralhan, Aerospace Engineer, 

International Branch, ANM–116, 

Transport Airplane Directorate, FAA, 

1601 Lind Avenue SW., Renton, 

Washington 98057–3356; telephone 

(425) 227–1405; fax (425) 227–1149. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

We invite you to send any written 

relevant data, views, or arguments about 

this proposed AD. Send your comments 

to an address listed under the 

ADDRESSES section. Include ‘‘Docket No. 

FAA–2009–0714; Directorate Identifier 

2009–NM–041–AD’’ at the beginning of 

your comments. We specifically invite 


CPrice-Sewell on DSK1DXX6B1PROD with PROPOSALS
Federal Register / Vol. 74, No. 159 / Wednesday, August 19, 2009 / Proposed Rules 41811 

comments on the overall regulatory, 

economic, environmental, and energy 

aspects of this proposed AD. We will 

consider all comments received by the 

closing date and may amend this 

proposed AD based on those comments. 

We will post all comments we 

receive, without change, to http:// 

www.regulations.gov, including any 

personal information you provide. We 

will also post a report summarizing each 

substantive verbal contact we receive 

about this proposed AD. 

Discussion 

The Ageˆncia Nacional de Aviac ̧a ̃o 

Civil (ANAC), which is the aviation 

authority for Brazil, has issued Brazilian 

Airworthiness Directive 2009–01–01, 

effective January 8, 2009, as corrected 

by Brazilian Airworthiness Directive 

Errata, effective January 20, 2009 

(referred to after this as ‘‘the MCAI’’), to 

correct an unsafe condition for the 

specified products. The MCAI states: 

It was reported that after commanding the 

landing gear lever to down the three green 

landing gear positioning indication was 

displayed followed by the LG/LEVER 

DISAGREE EICAS [engine indicating and 

crew alerting system] message. The crew 

decided to continue the approach and 

landing procedure. As soon as the crew 

identified that the landing gear was not 

extended properly, a go-around procedure 

was successfully performed. During 

maneuver, the airplane settled momentarily 

onto the flaps and belly. 

* * * * * 

The unsafe condition is the landing gear 

remaining in the up and locked position 

during approach and landing and 

accompanied by an invalid EICAS 

landing gear position indication, which 

could result in landing with gear in the 

up position, and eliminate 

controllability of the airplane on 

ground. This may consequently result in 

structural damage to the airplane. 

Required actions include replacing the 

landing gear electronic unit with a new 

one having a new part number. You may 

obtain further information by examining 

the MCAI in the AD docket. 

Relevant Service Information 

Embraer has issued Service Bulletins 

145–32–0120, Revision 01, dated 

November 4, 2008; and 145LEG–32– 

0032, Revision 02, dated February 17, 

2009. The actions described in this 

service information are intended to 

correct the unsafe condition identified 

in the MCAI. 

FAA’s Determination and Requirements 

of This Proposed AD 

This product has been approved by 

the aviation authority of another 

country, and is approved for operation 

in the United States. Pursuant to our 

bilateral agreement with the State of 

Design Authority, we have been notified 

of the unsafe condition described in the 

MCAI and service information 

referenced above. We are proposing this 

AD because we evaluated all pertinent 

information and determined an unsafe 

condition exists and is likely to exist or 

develop on other products of the same 

type design. 

Differences Between This AD and the 

MCAI or Service Information 

We have reviewed the MCAI and 

related service information and, in 

general, agree with their substance. But 

we might have found it necessary to use 

different words from those in the MCAI 

to ensure the AD is clear for U.S. 

operators and is enforceable. In making 

these changes, we do not intend to differ 

substantively from the information 

provided in the MCAI and related 

service information. 

We might also have proposed 

different actions in this AD from those 

in the MCAI in order to follow FAA 

policies. Any such differences are 

highlighted in a NOTE within the 

proposed AD. 

Costs of Compliance 

Based on the service information, we 

estimate that this proposed AD would 

affect about 711 products of U.S. 

registry. We also estimate that it would 

take about 2 work-hours per product to 

comply with the basic requirements of 

this proposed AD. The average labor 

rate is $80 per work-hour. Required 

parts would cost about $0 per product. 

Where the service information lists 

required parts costs that are covered 

under warranty, we have assumed that 

there will be no charge for these costs. 

As we do not control warranty coverage 

for affected parties, some parties may 

incur costs higher than estimated here. 

Based on these figures, we estimate the 

cost of the proposed AD on U.S. 

operators to be $113,760, or $160 per 

product. 

Authority for This Rulemaking 

Title 49 of the United States Code 

specifies the FAA’s authority to issue 

rules on aviation safety. Subtitle I, 

section 106, describes the authority of 

the FAA Administrator. ‘‘Subtitle VII: 

Aviation Programs,’’ describes in more 

detail the scope of the Agency’s 

authority. 

We are issuing this rulemaking under 

the authority described in ‘‘Subtitle VII, 

Part A, Subpart III, Section 44701: 

General requirements.’’ Under that 

section, Congress charges the FAA with 

promoting safe flight of civil aircraft in 

air commerce by prescribing regulations 

for practices, methods, and procedures 

the Administrator finds necessary for 

safety in air commerce. This regulation 

is within the scope of that authority 

because it addresses an unsafe condition 

that is likely to exist or develop on 

products identified in this rulemaking 

action. 

Regulatory Findings 

We determined that this proposed AD 

would not have federalism implications 

under Executive Order 13132. This 

proposed AD would not have a 

substantial direct effect on the States, on 

the relationship between the national 

Government and the States, or on the 

distribution of power and 

responsibilities among the various 

levels of government. 

For the reasons discussed above, I 

certify this proposed regulation: 

1. Is not a ‘‘significant regulatory 

action’’ under Executive Order 12866; 

2. Is not a ‘‘significant rule’’ under the 

DOT Regulatory Policies and Procedures 

(44 FR 11034, February 26, 1979); and 

3. Will not have a significant 

economic impact, positive or negative, 

on a substantial number of small entities 

under the criteria of the Regulatory 

Flexibility Act. 

We prepared a regulatory evaluation 

of the estimated costs to comply with 

this proposed AD and placed it in the 

AD docket. 

List of Subjects in 14 CFR Part 39 

Air transportation, Aircraft, Aviation 

safety, Incorporation by reference, 

Safety. 

The Proposed Amendment 

Accordingly, under the authority 

delegated to me by the Administrator, 

the FAA proposes to amend 14 CFR part 

39 as follows: 

PART 39—AIRWORTHINESS 

DIRECTIVES 

1. The authority citation for part 39 

continues to read as follows: 

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

§ 39.13 [Amended] 

2. The FAA amends § 39.13 by adding 

the following new AD: 

Empresa Brasileira de Aeronautica S.A. 

(EMBRAER): Docket No. FAA–2009– 

0714; Directorate Identifier 2009–NM– 

041–AD. 

Comments Due Date 

(a) We must receive comments by 

September 18, 2009. 

Affected ADs 

(b) None. 


CPrice-Sewell on DSK1DXX6B1PROD with PROPOSALS
41812 Federal Register / Vol. 74, No. 159 / Wednesday, August 19, 2009 / Proposed Rules 

Applicability 

(c) This AD applies to EMBRAER Model 

EMB–135BJ, –135ER, –135KE, –135KL, 

–135LR, –145, –145ER, –145MR, –145LR, 

–145XR, –145MP, and –145EP airplanes, 

certificated in any category, modified 

according to Brazilian Supplemental Type 

Certificate 2002S06–09, 2002S06–10 or 

2003S08–01, and equipped with landing gear 

electronic unit (LGEU) part number (P/N) 

355–022–002. 

Subject 

(d) Air Transport Association (ATA) of 

America Code 32: Landing gear. 

Reason 

(e) The mandatory continuing 

airworthiness information (MCAI) states: 

It was reported that after commanding the 

landing gear lever to down the three green 

landing gear positioning indication was 

displayed followed by the LG/LEVER 

DISAGREE EICAS [engine indicating and 

crew alerting system] message. The crew 

decided to continue the approach and 

landing procedure. As soon as the crew 

identified that the landing gear was not 

extended properly, a go-around procedure 

was successfully performed. 

During maneuver, the airplane settled 

momentarily onto the flaps and belly. 

* * * * * 

The unsafe condition is the landing gear 

remaining in the up and locked position 

during approach and landing and 

accompanied by an invalid EICAS landing 

gear position indication, which could result 

in landing with gear in the up position, and 

eliminate controllability of the airplane on 

ground. This may consequently result in 

structural damage to the airplane. Required 

actions include replacing the LGEU with a 

new one having a new part number. 

Actions and Compliance 

(f) Unless already done, do the following 

actions: 

(1) Within 12 months after the effective 

date of this AD, replace any LGEU P/N 355– 

022–002 having a serial number (S/N) 1000 

through 1999 inclusive with a new LGEU 

having P/N 355–022–003, in accordance with 

the Accomplishment Instructions of Embraer 

Service Bulletin 145–32–0120, Revision 01, 

dated November 4, 2008; or 145LEG–32– 

0032, Revision 02, dated February 17, 2009; 

as applicable. 

(2) As of 12 months after the effective date 

of this AD, no person may install on any 

airplane an LGEU having a P/N 355–022–002 

and S/N 1000 through 1999 inclusive. 

(3) Within 30 months after the effective 

date of this AD, replace any LGEU P/N 355– 

022–002 having a serial number not 

identified in paragraph (f)(1) of this AD, with 

a new LGEU having a P/N 355–022–003, in 

accordance with the Accomplishment 

Instructions of Embraer Service Bulletin 145– 

32–0120, Revision 01, dated November 4, 

2008; or 145LEG–32–0032, Revision 02, 

dated February 17, 2009; as applicable. 

(4) As of 30 months after the effective date 

of this AD, no person may install on any 

airplane an LGEU having a P/N 355–022– 

002. 

(5) Replacement of the LGEU is also 

acceptable for compliance with the 

requirements of paragraph (f) of this AD if 

done before the effective date of this AD in 

accordance with one of the service bulletins 

identified in Table 1 of this AD: 

TABLE 1—CREDIT SERVICE BULLETINS

Embraer Service Bulletin— Revision— Dated— 

145LEG–32–0032 ............................................................... Original ............................................................................... October 8, 2008. 

145LEG–32–0032 ............................................................... 01 ....................................................................................... November 4, 2008. 

145–32–0120 ...................................................................... Original ............................................................................... September 15, 2008. 

FAA AD Differences 

Note 1: This AD differs from the MCAI 

and/or service information as follows: 

Although Embraer Service Bulletins 

145LEG–32–0032, Revision 02, dated 

February 17, 2009; and 145–32–0120, 

Revision 01, dated November 4, 2008; specify 

that no person may install on any airplane an 

LGEU P/N 355–022–002 as of 30 months after 

the effective date of this AD, we have 

determined that no LGEU P/N 355–022–002 

with a S/N 1000 through 1999 inclusive may 

be installed 12 months after the effective date 

of this AD. Allowing installation of those 

serial numbers beyond 12 months would not 

address the identified unsafe condition and 

ensure an adequate level of safety. This 

difference has been coordinated with the 

Ageˆncia Nacional de Aviac ̧a ̃o Civil (ANAC). 

Other FAA AD Provisions 

(g) The following provisions also apply to 

this AD: 

(1) Alternative Methods of Compliance 

(AMOCs): The Manager, International 

Branch, ANM–116, FAA, has the authority to 

approve AMOCs for this AD, if requested 

using the procedures found in 14 CFR 39.19. 

Send information to ATTN: Sanjay Ralhan, 

Aerospace Engineer, International Branch, 

ANM–116, Transport Airplane Directorate, 

FAA, 1601 Lind Avenue, SW., Renton, 

Washington 98057–3356; telephone (425) 

227–1405; fax (425) 227–1149. Before using 

any approved AMOC on any airplane to 

which the AMOC applies, notify your 

principal maintenance inspector (PMI) or 

principal avionics inspector (PAI), as 

appropriate, or lacking a principal inspector, 

your local Flight Standards District Office. 

The AMOC approval letter must specifically 

reference this AD. 

(2) Airworthy Product: For any requirement 

in this AD to obtain corrective actions from 

a manufacturer or other source, use these 

actions if they are FAA-approved. Corrective 

actions are considered FAA-approved if they 

are approved by the State of Design Authority 

(or their delegated agent). You are required 

to assure the product is airworthy before it 

is returned to service. 

(3) Reporting Requirements: For any 

reporting requirement in this AD, under the 

provisions of the Paperwork Reduction Act, 

the Office of Management and Budget (OMB) 

has approved the information collection 

requirements and has assigned OMB Control 

Number 2120–0056. 

Related Information 

(h) Refer to MCAI ANAC Airworthiness 

Directive 2009–01–01, effective January 8, 

2009, as corrected by Brazilian Airworthiness 

Directive Errata, effective January 20, 2009; 

and the service bulletins listed in Table 2 of 

this AD; for related information. 

TABLE 2—RELATED SERVICE BULLETINS

Embraer Service Bulletin— Revision— Dated— 

145–32–0120 ...................................................................................................................................... 01 November 4, 2008. 

145LEG–32–0032 ............................................................................................................................... 02 February 17, 2009. 


CPrice-Sewell on DSK1DXX6B1PROD with PROPOSALS
Federal Register / Vol. 74, No. 159 / Wednesday, August 19, 2009 / Proposed Rules 41813 

Issued in Renton, Washington, on August 

7, 2009. 

Stephen P. Boyd, 

Acting Manager, Transport Airplane 

Directorate, Aircraft Certification Service. 

[FR Doc. E9–19853 Filed 8–18–09; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2009–0686; Directorate 

Identifier 2009–NM–044–AD] 

RIN 2120–AA64 

Airworthiness Directives; McDonnell 

Douglas Model MD–11 and MD–11F 

Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Notice of proposed rulemaking 

(NPRM). 

SUMMARY: We propose to adopt a new 

airworthiness directive (AD) for certain 

McDonnell Douglas Model MD–11 and 

MD–11F airplanes. This proposed AD 

would require a one-time inspection to 

determine if wires touch the upper 

surface of the center upper auxiliary 

fuel tank and marking the location, if 

necessary; a one-time inspection of all 

wire bundles above the center upper 

auxiliary fuel tank for splices and 

damage; a one-time inspection for 

damage to the fuel vapor barrier seal 

and upper surface of the center upper 

auxiliary fuel tank; and corrective 

actions, if necessary. This proposed AD 

would also require installation of 

nonmetallic barrier/shield sleeving, new 

clamps, new attaching hardware, and a 

new extruded channel. This proposed 

AD results from fuel system reviews 

conducted by the manufacturer. We are 

proposing this AD to reduce the 

potential of ignition sources inside fuel 

tanks, which, in combination with 

flammable fuel vapors, could result in 

fuel tank explosions and consequent 

loss of the airplane. 

DATES: We must receive comments on 

this proposed AD by October 5, 2009. 

ADDRESSES: You may send comments by 

any of the following methods: 

• Federal eRulemaking Portal: Go to 

http://www.regulations.gov. Follow the 

instructions for submitting comments. 

• Fax: 202–493–2251. 

• Mail: U.S. Department of 

Transportation, Docket Operations, M– 

30, West Building Ground Floor, Room 

W12–140, 1200 New Jersey Avenue, SE., 

Washington, DC 20590. 

• Hand Delivery: U.S. Department of 

Transportation, Docket Operations, M– 

30, West Building Ground Floor, Room 

W12–140, 1200 New Jersey Avenue, SE., 

Washington, DC 20590, between 9 a.m. 

and 5 p.m., Monday through Friday, 

except Federal holidays. 

For service information identified in 

this proposed AD, contact Boeing 

Commercial Airplanes, Attention: Data 

& Services Management, 3855 

Lakewood Boulevard, MC D800–0019, 

Long Beach, California 90846–0001; 

telephone 206–544–5000, extension 2; 

fax 206–766–5683; e-mail 

dse.boecom@boeing.com; Internet 

https://www.myboeingfleet.com. You 

may review copies of the referenced 

service information at the FAA, 

Transport Airplane Directorate, 1601 

Lind Avenue, SW., Renton, Washington. 

For information on the availability of 

this material at the FAA, call 425–227– 

1221 or 425–227–1152. 

Examining the AD Docket 

You may examine the AD docket on 

the Internet at http:// 

www.regulations.gov; or in person at the 

Docket Management Facility between 9 

a.m. and 5 p.m., Monday through 

Friday, except Federal holidays. The AD 

docket contains this proposed AD, the 

regulatory evaluation, any comments 

received, and other information. The 

street address for the Docket Office 

(telephone 800–647–5527) is in the 

ADDRESSES section. Comments will be 

available in the AD docket shortly after 

receipt. 

FOR FURTHER INFORMATION CONTACT: 

Samuel Lee, Aerospace Engineer, 

Propulsion Branch, ANM–140L, FAA, 

Los Angeles Aircraft Certification 

Office, 3960 Paramount Boulevard, 

Lakewood, California 90712–4137; 

telephone (562) 627–5262; fax (562) 

627–5210. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

We invite you to send any written 

relevant data, views, or arguments about 

this proposed AD. Send your comments 

to an address listed under the 

ADDRESSES section. Include ‘‘Docket No. 

FAA–2009–0686; Directorate Identifier 

2009–NM–044–AD’’ at the beginning of 

your comments. We specifically invite 

comments on the overall regulatory, 

economic, environmental, and energy 

aspects of this proposed AD. We will 

consider all comments received by the 

closing date and may amend this 

proposed AD because of those 

comments. 

We will post all comments we 

receive, without change, to http:// 

www.regulations.gov, including any 

personal information you provide. We 

will also post a report summarizing each 

substantive verbal contact we receive 

about this proposed AD. 

Discussion 

The FAA has examined the 

underlying safety issues involved in fuel 

tank explosions on several large 

transport airplanes, including the 

adequacy of existing regulations, the 

service history of airplanes subject to 

those regulations, and existing 

maintenance practices for fuel tank 

systems. As a result of those findings, 

we issued a regulation titled ‘‘Transport 

Airplane Fuel Tank System Design 

Review, Flammability Reduction and 

Maintenance and Inspection 

Requirements’’ (67 FR 23086, May 7, 

2001). In addition to new airworthiness 

standards for transport airplanes and 

new maintenance requirements, this 

rule included Special Federal Aviation 

Regulation No. 88 (‘‘SFAR 88,’’ 

Amendment 21–78, and subsequent 

Amendments 21–82 and 21–83). 

Among other actions, SFAR 88 

requires certain type design (i.e., type 

certificate (TC) and supplemental type 

certificate (STC)) holders to substantiate 

that their fuel tank systems can prevent 

ignition sources in the fuel tanks. This 

requirement applies to type design 

holders for large turbine-powered 

transport airplanes and for subsequent 

modifications to those airplanes. It 

requires them to perform design reviews 

and to develop design changes and 

maintenance procedures if their designs 

do not meet the new fuel tank safety 

standards. As explained in the preamble 

to the rule, we intended to adopt 

airworthiness directives to mandate any 

changes found necessary to address 

unsafe conditions identified as a result 

of these reviews. 

In evaluating these design reviews, we 

have established four criteria intended 

to define the unsafe conditions 

associated with fuel tank systems that 

require corrective actions. The 

percentage of operating time during 

which fuel tanks are exposed to 

flammable conditions is one of these 

criteria. The other three criteria address 

the failure types under evaluation: 

single failures, single failures in 

combination with another latent 

condition(s), and in-service failure 

experience. For all four criteria, the 

evaluations included consideration of 

previous actions taken that may mitigate 

the need for further action. 

We have determined that the actions 

identified in this AD are necessary to 

reduce the potential of ignition sources 

inside fuel tanks, which, in combination 


CPrice-Sewell on DSK1DXX6B1PROD with PROPOSALS