Federal Register / Vol. 74, No. 189 / Thursday, October 1, 2009 / Rules and Regulations 50683 

adopting the interim final rule as a final 

rule, without change. 

To view the interim final rule, go to 

http://www.regulations.gov/search/

Regs/home.html#documentDetail?

R=09000064809d2903. 

This action also affirms information 

contained in the interim final rule 

concerning Executive Orders 12866 and 

12988, the Paperwork Reduction Act (44 

U.S.C. Chapter 35), and the E-Gov Act 

(44 U.S.C. 101). 

After consideration of all relevant 

material presented, it is found that 

finalizing the interim final rule, without 

change, as published in the Federal 

Register (74 FR 28872, June 18, 2009) 

will tend to effectuate the declared 

policy of the Act. 

List of Subjects in 7 CFR Part 981 

Almonds, Marketing agreements, 

Nuts, Reporting and recordkeeping 

requirements. 

PART 981—ALMONDS GROWN IN 

CALIFORNIA 

Accordingly, the interim final rule 

that amended 7 CFR part 981 and that 

was published at 74 FR 28872, on June 

18, 2009, is adopted as a final rule, 

without change. 

Dated: September 25, 2009. 

Rayne Pegg, 

Administrator, Agricultural Marketing 

Service. 

[FR Doc. E9–23648 Filed 9–30–09; 8:45 am] 

BILLING CODE 3410–02–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2009–0521; Directorate 

Identifier 2008–NM–187–AD; Amendment 

39–16034; AD 2009–20–11] 

RIN 2120–AA64 

Airworthiness Directives; Boeing 

Model 737–300, –400, and –500 Series 

Airplanes Equipped With a Digital 

Transient Suppression Device (DTSD) 

Installed in Accordance With 

Supplemental Type Certificate (STC) 

ST00127BO 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final rule. 

SUMMARY: We are adopting a new 

airworthiness directive (AD) for certain 

Boeing Model 737–300, –400, and –500 

series airplanes. This AD requires 

revising the maintenance program to 

include new fuel system limitations for 

airplanes modified in accordance with 

STC ST00127BO. This AD also requires 

inspections and checks of the DTSDs 

and corrective actions, if necessary. This 

AD results from fuel system reviews 

conducted by the manufacturer. We are 

issuing this AD to prevent a potential of 

ignition sources inside fuel tanks, 

which, in combination with flammable 

fuel vapors, could result in a fuel tank 

fire or explosion and consequent loss of 

the airplane. 

DATES: This AD is effective November 5, 

2009. 

The Director of the Federal Register 

approved the incorporation by reference 

of certain publications listed in the AD 

as of November 5, 2009. 

ADDRESSES: For service information 

identified in this AD, contact Goodrich 

Corporation, Fuel and Utility Systems, 

100 Panton Road, Vergennes, Vermont 

05491–1008; telephone 802–877–4476; 

e-mail 

lgd.TechPubs.Oakville@goodrich.com; 

Internet http://www.goodrich.com/ 

TechPubs. 

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 AD, the regulatory 

evaluation, any comments received, and 

other information. The address for the 

Docket Office (telephone 800–647–5527) 

is the Document Management Facility, 

U.S. Department of Transportation, 

Docket Operations, M–30, West 

Building Ground Floor, Room W12–140, 

1200 New Jersey Avenue, SE., 

Washington, DC 20590. 

FOR FURTHER INFORMATION CONTACT: 

Marc Ronell, Aerospace Engineer, ANE– 

150, FAA, Boston Aircraft Certification 

Office, 12 New England Executive Park, 

Burlington, Massachusetts 01803; 

telephone (781) 238–7776; fax (781) 

238–7170. 

SUPPLEMENTARY INFORMATION: 

Discussion 

We issued a notice of proposed 

rulemaking (NPRM) to amend 14 CFR 

part 39 to include an airworthiness 

directive (AD) that would apply to 

certain Boeing Model 737–300, –400, 

and –500 series airplanes. That NPRM 

was published in the Federal Register 

on June 9, 2009 (74 FR 27254). That 

NPRM proposed to require revising the 

maintenance program to include new 

fuel system limitations for airplanes 

modified in accordance with 

Supplemental Type Certificate (STC) 

ST00127BO. That NPRM also proposed 

to require inspections and checks of the 

digital transient suppression devices 

and corrective actions, if necessary. 

Comments 

We gave the public the opportunity to 

participate in developing this AD. We 

considered the comment received. 

Boeing supports the NPRM. 

Actions Since NPRM was Issued 

Since we issued the NPRM, we have 

determined that it is necessary to clarify 

the AD’s intended effect on spare and 

on-airplane fuel tank system 

components, regarding the use of 

maintenance manuals and instructions 

for continued airworthiness. 

Section 91.403(c) of the Federal 

Aviation Regulations (14 CFR 91.403(c)) 

specifies the following: 

No person may operate an aircraft for 

which a manufacturer’s maintenance manual 

or instructions for continued airworthiness 

has been issued that contains an 

airworthiness limitation section unless the 

mandatory * * * procedures * * * have 

been complied with. 

Some operators have questioned 

whether existing components affected 

by the new CDCCLs must be reworked. 

We did not intend for the AD to 

retroactively require rework of 

components that had been maintained 

using acceptable methods before the 

effective date of the AD. Owners and 

operators of the affected airplanes 

therefore are not required to rework 

affected components identified as 

airworthy or installed on the affected 

airplanes before the required revisions 

of the maintenance program. But once 

the CDCCLs are incorporated into the 

maintenance program, future 

maintenance actions on components 

must be done in accordance with those 

CDCCLs. 

We have added Note 2 to this AD to 

clarify the intended effect of the AD on 

spare and on-airplane fuel tank system 

components. 

Conclusion 

We reviewed the relevant data, 

including the comment received, and 

determined that air safety and the 

public interest require adopting the AD 

with the change described previously. 

We also determined that this change 

will not increase the economic burden 

on any operator or increase the scope of 

the AD. 

Costs of Compliance 

We estimate that this AD affects 12 

airplanes of U.S. registry. The following 

table provides the estimated costs for 

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50684 Federal Register / Vol. 74, No. 189 / Thursday, October 1, 2009 / Rules and Regulations 

U.S. operators to comply with this AD. The average labor rate is $80 per work 

hour. 

ESTIMATED COSTS

Action Work hours Cost per 

product Fleet cost 

Revision to maintenance program ............................................................................................... 8 $640 $7,680 

Operational check, per cycle ....................................................................................................... 1 80 960 

Bond damage inspection, per cycle ............................................................................................ 1 80 960 

Separation inspection, per cycle ................................................................................................. 1 80 960 

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 

This AD will not have federalism 

implications under Executive Order 

13132. This AD will 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 that this AD: 

(1) Is not a ‘‘significant regulatory 

action’’ under Executive Order 12866, 

(2) Is not a ‘‘significant rule’’ under 

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. 

You can find our regulatory 

evaluation and the estimated costs of 

compliance in the AD Docket. 

List of Subjects in 14 CFR Part 39 

Air transportation, Aircraft, Aviation 

safety, Incorporation by reference, 

Safety. 

Adoption of the Amendment 

■ Accordingly, under the authority 

delegated to me by the Administrator, 

the FAA amends 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: 

2009–20–11 Boeing: Amendment 39–16034. 

Docket No. FAA–2009–0521; Directorate 

Identifier 2008–NM–187–AD. 

Effective Date 

(a) This airworthiness directive (AD) is 

effective November 5, 2009. 

Affected ADs 

(b) None. 

Applicability 

(c) This AD applies to Boeing Model 737– 

300, –400, and –500 series airplanes, 

certificated in any category, equipped with a 

digital transient suppression device (DTSD) 

installed in accordance with Supplemental 

Type Certificate (STC) ST00127BO. 

Note 1: This AD requires revisions to 

certain operator maintenance documents to 

include new inspections. Compliance with 

these inspections is required by 14 CFR 

91.403(c). For airplanes that have been 

previously modified, altered, or repaired in 

the areas addressed by these inspections, the 

operator may not be able to accomplish the 

inspections described in the revisions. In this 

situation, to comply with 14 CFR 91.403(c), 

the operator must request approval for an 

alternative method of compliance according 

to paragraph (m) of this AD. The request 

should include a description of changes to 

the required inspections that will ensure the 

continued operational safety of the airplane. 

Subject 

(d) Air Transport Association (ATA) of 

America Code 28: Fuel. 

Unsafe Condition 

(e) This AD results from fuel system 

reviews conducted by the manufacturer. We 

are issuing this AD to prevent a potential of 

ignition sources inside fuel tanks, which in 

combination with flammable fuel vapors, 

could result in a fuel tank fire or explosion 

and consequent loss of the airplane. 

Compliance 

(f) You are responsible for having the 

actions required by this AD performed within 

the compliance times specified, unless the 

actions have already been done. 

Revision to the Maintenance Program to Add 

Critical Design Configuration Control 

Limitations (CDCCLs) Specified in Section 

10.1 of the Service Information 

(g) Within 30 days after the effective date 

of this AD: Revise the maintenance program 

to incorporate the fuel system limitations 

specified in Section 10.1 of the Goodrich 

Instructions for Continued Airworthiness for 

the Transient Suppression Device Installation 

Applicable to Boeing 737–300, –400, & –500 

Airplanes Supplemental Type Certificate— 

ST00127BO, Document T2007–0010–0101, 

Revision D, dated January 16, 2007. 

Revision to the Maintenance Program to Add 

Scheduled Inspections/Operational Checks 

(h) Within 30 days after the effective date 

of this AD: Revise the maintenance program 

to incorporate the scheduled inspections/ 

operational checks specified in Section 2.2.3 

of the Goodrich Instructions for Continued 

Airworthiness for the Transient Suppression 

Device Installation Applicable to Boeing 

737–300, –400, & –500 Airplanes 

Supplemental Type Certificate—ST00127BO, 

Document T2007–0010–0101, Revision D, 

dated January 16, 2007; except that the initial 

inspections/checks required by paragraphs 

(i), (j), and (k) of this AD must be done at the 

compliance times specified in those 

paragraphs. Repeat the inspections/checks 

thereafter at the applicable compliance times 

in the column, ‘‘Frequency,’’ of the table 

specified in Section 2.2.3 of the Goodrich 

Instructions for Continued Airworthiness for 

the Transient Suppression Device Installation 

Applicable to Boeing 737–300, –400, & –500 

Airplanes Supplemental Type Certificate— 

ST00127BO, Document T2007–0010–0101, 

Revision D, dated January 16, 2007. 

Initial Inspections and Repair if Necessary 

(i) Prior to the accumulation of 39,000 

flight hours after modification in accordance 

with STC ST00127BO, or within 12 months 

after the effective date of this AD, whichever 

occurs later: Do an operational check of the 

DTSDs, in accordance with Section 2.2.3, 

‘‘Scheduled Inspections/Operational 

Checks,’’ of the Goodrich Instructions for 

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Federal Register / Vol. 74, No. 189 / Thursday, October 1, 2009 / Rules and Regulations 50685 

Continued Airworthiness for the Transient 

Suppression Device Installation Applicable 

to Boeing 737–300, –400, & –500 Airplanes 

Supplemental Type Certificate—ST00127BO, 

Document T2007–0010–0101, Revision D, 

dated January 16, 2007. If the DTSD fails the 

operational check, repair before further flight, 

in accordance with the section of the 

Goodrich Aircraft Maintenance Manual 

Supplement with Wiring Diagrams, 737–300/ 

–400/–500 FQIS with Goodrich Digital 

Indicators and Transient Suppression Device, 

STC Number: ST00127BO, Revision 5, dated 

December 20, 2006, that corresponds to the 

operational check specified in Goodrich 

Instructions for Continued Airworthiness for 

the Transient Suppression Device Installation 

Applicable to Boeing 737–300, –400, & –500 

Airplanes Supplemental Type Certificate— 

ST00127BO, Document T2007–0010–0101, 

Revision D, dated January 16, 2007. 

(j) Prior to the accumulation of 4,000 flight 

hours after modification in accordance with 

STC ST00127BO, or within 6 months after 

the effective date of this AD, whichever 

occurs later: Do a general visual inspection 

for critical bond damage of the DTSD safeside harnesses (critical bond damage 

includes measuring the bonding resistance 

across the ground strap and verifying the 

resistance is less than 2.0 milliohms), in 

accordance with Section 2.2.3, ‘‘Scheduled 

Inspections/Operational Checks,’’ of 

Goodrich Instructions for Continued 

Airworthiness for the Transient Suppression 

Device Installation Applicable to Boeing 

737–300, –400, & –500 Airplanes 

Supplemental Type Certificate—ST00127BO, 

Document T2007–0010–0101, Revision D, 

dated January 16, 2007, which includes Items 

5, 6, 7, and 8 of Table 6 in Section 10.1, 

‘‘Fuel System Limitations.’’ If any damage is 

found, repair before further flight, in 

accordance with the section of the Goodrich 

Aircraft Maintenance Manual Supplement 

with Wiring Diagrams for 737–300/–400/– 

500 FQIS with Goodrich Aircraft 

Maintenance Manual Supplement with 

Wiring Diagrams, 737–300/–400/–500 FQIS 

with Goodrich Digital Indicators and 

Transient Suppression Device, STC Number: 

ST00127BO, Revision 5, dated December 20, 

2006, that corresponds to the general visual 

inspection specified in Goodrich Instructions 

for Continued Airworthiness for the 

Transient Suppression Device Installation 

Applicable to Boeing 737–300, –400, & –500 

Airplanes Supplemental Type Certificate— 

ST00127BO, Document T2007–0010–0101, 

Revision D, dated January 16, 2007. 

(k) Prior to the accumulation of 24,000 

flight hours after modification in accordance 

with STC ST00127BO, or within 12 months 

after the effective date of this AD, whichever 

occurs later: Do a general visual inspection 

for physical separation of the DTSD safe-side 

harnesses from other airplane wiring, 

hydraulic tubing, structure, control cables, 

and bleed air ducts, in accordance with 

Section 2.2.3, ‘‘Scheduled Inspections/ 

Operational Checks,’’ of the Goodrich 

Instructions for Continued Airworthiness for 

the Transient Suppression Device Installation 

Applicable to Boeing 737–300, –400, & –500 

Airplanes Supplemental Type Certificate— 

ST00127BO, Document T2007–0010–0101, 

Revision D, dated January 16, 2007. If any 

damage is found, repair before further flight, 

in accordance with the section of the 

Goodrich Aircraft Maintenance Manual 

Supplement with Wiring Diagrams for 737– 

300/–400/–500 FQIS with Goodrich Digital 

Indicators and Transient Suppression Device, 

STC Number: ST00127BO, Revision 5, dated 

December 20, 2006, that corresponds to the 

general visual inspection specified in 

Goodrich Instructions for Continued 

Airworthiness for the Transient Suppression 

Device Installation Applicable to Boeing 

737–300, –400, & –500 Airplanes 

Supplemental Type Certificate—ST00127BO, 

Document T2007–0010–0101, Revision D, 

dated January 16, 2007. 

No Alternative Inspections/Checks, 

Inspection/Check Intervals, or CDCCLs 

(l) After accomplishing the actions 

specified in paragraphs (g) and (h) of this AD, 

no alternative inspections/checks, 

inspection/check intervals, or CDCCLs may 

be used unless the inspections/checks, 

intervals, or CDCCLs are approved as an 

alternative method of compliance (AMOC) in 

accordance with the procedures specified in 

paragraph (m) of this AD. 

Note 2: Notwithstanding any other 

maintenance or operational requirements, 

components that have been identified as 

airworthy or installed on the affected 

airplanes before the revision of the 

maintenance program, as required by 

paragraph (g) of this AD, do not need to be 

reworked in accordance with the CDCCLs. 

However, once the maintenance program has 

been revised, future maintenance actions on 

these components must be done in 

accordance with the CDCCLs. 

AMOCs 

(m)(1) The Manager, Boston Aircraft 

Certification Office, 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: Marc Ronell, 

Aerospace Engineer, ANE–150, FAA, Boston 

Aircraft Certification Office, 12 New England 

Executive Park, Burlington, Massachusetts 

01803; telephone (781) 238–7776; fax (781) 

238–7170. 

(2) To request a different method of 

compliance or a different compliance time 

for this AD, follow the procedures in 14 CFR 

39.19. 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. 

Material Incorporated by Reference 

(n) You must use the service information 

contained in Table 1 of this AD to do the 

actions required by this AD, as applicable, 

unless the AD specifies otherwise. 

TABLE 1—MATERIAL INCORPORATED BY REFERENCE

Document Revision Date 

Goodrich Aircraft Maintenance Manual Supplement with Wiring Diagrams, 737–300/–400/–500 FQIS with 

Goodrich Digital Indicators and Transient Suppression Device, STC Number: ST00127BO.

5 December 20, 2006. 

Goodrich Instructions for Continued Airworthiness for the Transient Suppression Device Installation Applicable to Boeing 737–300, –400, & –500 Airplanes Supplemental Type Certificate—ST00127BO, Document T2007–0010–0101.D January 16, 2007. 

(The List of Effective Pages (LOEP) for 

Goodrich Aircraft Maintenance Manual 

Supplement with Wiring Diagrams, 737–300/ 

–400/–500 FQIS with Goodrich Digital 

Indicators and Transient Suppression Device, 

STC Number: ST00127BO, contains the 

following errors: Page TOC–1 is dated 

December 20, 2006, not June 1, 2002, as 

indicated in the LOEP; the odd-numbered 

pages of the Appendix—Wiring Diagrams are 

dated April 16, 2004, not August 15, 2005, 

as indicated in the LOEP.) 

(1) The Director of the Federal Register 

approved the incorporation by reference of 

this service information under 5 U.S.C. 

552(a) and 1 CFR part 51. 

(2) For service information identified in 

this AD, contact Goodrich Corporation, Fuel 

and Utility Systems, 100 Panton Road, 

Vergennes, Vermont 05491–1008; telephone 

802–877–4476; e-mail 

lgd.TechPubs.Oakville@goodrich.com; 

Internet http://www.goodrich.com/TechPubs. 

(3) You may review copies of the 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. 

(4) You may also review copies of the 

service information that is incorporated by 

reference at the National Archives and 

Records Administration (NARA). For 

information on the availability of this 

material at NARA, call 202–741–6030, or go 

to: http://www.archives.gov/federal_register/ 

code_of_federal_regulations/ 

ibr_locations.html. 

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50686 Federal Register / Vol. 74, No. 189 / Thursday, October 1, 2009 / Rules and Regulations 

Issued in Renton, Washington, on 

September 18, 2009. 

Ali Bahrami, 

Manager, Transport Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. E9–23509 Filed 9–30–09; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2009–0293; Directorate 

Identifier 2008–NM–221–AD; Amendment 

39–16035; AD 2009–20–12] 

RIN 2120–AA64 

Airworthiness Directives; Boeing 

Model 747–100, –100B, –100B SUD, 

–200B, –200C, –200F, –300, –400, 

–400D, –400F, and 747SR Series 

Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final rule. 

SUMMARY: We are adopting a new 

airworthiness directive (AD) for certain 

Boeing Model 747 airplanes identified 

above. This AD requires replacing the 

inboard trailing edge (TE) flap 

transmission carbon disk no-back brakes 

with skewed roller no-back brakes at the 

TE flap transmission, positions 4 and 5. 

This AD results from reports of the 

inboard TE flaps blowing back due to 

the failure of a transmission carbon disk 

no-back brake. The no-back brake did 

not hold the TE flaps in the commanded 

position. We are issuing this AD to 

prevent a decrease of the aerodynamic 

controllability of the airplane, which 

could adversely affect the airplane’s 

continued safe flight and landing. 

DATES: This AD is effective November 5, 

2009. 

The Director of the Federal Register 

approved the incorporation by reference 

of a certain publication listed in the AD 

as of November 5, 2009. 

ADDRESSES: For service information 

identified in this AD, contact Boeing 

Commercial Airplanes, Attention: Data 

& Services Management, P.O. Box 3707, 

MC 2H–65, Seattle, Washington 98124– 

2207; telephone 206–544–5000, 

extension 1; fax 206–766–5680; e-mail 

me.boecom@boeing.com; Internet 

https://www.myboeingfleet.com. 

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 AD, the regulatory 

evaluation, any comments received, and 

other information. The address for the 

Docket Office (telephone 800–647–5527) 

is the Document Management Facility, 

U.S. Department of Transportation, 

Docket Operations, M–30, West 

Building Ground Floor, Room W12–140, 

1200 New Jersey Avenue, SE., 

Washington, DC 20590. 

FOR FURTHER INFORMATION CONTACT: 

Douglas Tsuji, Aerospace Engineer, 

Systems and Equipment Branch, ANM– 

130S, FAA, Seattle Aircraft Certification 

Office, 1601 Lind Avenue, SW., Renton, 

Washington 98057–3356; telephone 

(425) 917–6487; fax (425) 917–6590. 

SUPPLEMENTARY INFORMATION: 

Discussion 

We issued a notice of proposed 

rulemaking (NPRM) to amend 14 CFR 

part 39 to include an airworthiness 

directive (AD) that would apply to 

certain Boeing Model 747 Airplanes. 

That NPRM was published in the 

Federal Register on April 1, 2009 (74 FR 

14750). That NPRM proposed to require 

replacing the inboard trailing edge (TE) 

flap transmission carbon disk no-back 

brakes with skewed roller no-back 

brakes at the TE flap transmission, 

positions 4 and 5. 

Comments 

We gave the public the opportunity to 

participate in developing this AD. We 

considered the comments received from 

the three commenters. 

Support for the NPRM 

Boeing concurs with the contents of 

the NPRM. 

Clarification of Criteria for AD 

Lufthansa has doubts that all criteria 

for the issuance of an AD are met. The 

commenter states that there is no 

comprehensible technical background. 

We infer that the commenter is 

requesting that we withdraw the NPRM. 

We disagree. Although Boeing Special 

Attention Service Bulletin 747–27– 

2422, dated October 30, 2008, states that 

‘‘since 1999, four operators have 

reported that the inboard TE flaps blew 

back due to the failure of a transmission 

carbon disk no-back brake,’’ there have 

been ten reports of failed inboard and 

outboard carbon disk no-back brakes 

since 1973, and six reports since 1999. 

Nine of the reports were for the inboard 

no-back, and one for an outboard noback. All of the failures (i.e., 

uncommanded blowbacks) occurred at a 

sufficient altitude for the pilots to react 

and control the airplane. As a result of 

these events, Boeing conducted 

extensive lab tests to check the wear 

properties and friction characteristics of 

new and used carbon disk brakes. The 

tests revealed a wide variation in 

friction capability but no wear 

correlation between friction coefficient 

and the number of cycles. Therefore, the 

carbon brake may be ineffective 

regardless of wear. Because of the test 

results and the number of events that 

have occurred in the fleet, we find it 

was necessary to proceed with issuing 

this AD to ensure the safety of the fleet. 

Request to Include an Optional Method 

of Compliance 

Lufthansa requests that we include a 

repetitive D-Check shop overhaul (with 

updated procedures, if necessary) as an 

optional method of compliance to the 

proposed modification. Lufthansa states 

that no-back brakes are removed every 

6 years during D-Check and are 

overhauled in accordance with the latest 

Boeing overhaul manuals. Lufthansa 

states that since 1995 there have been 

no failures of the brake system, or a flap 

blow back event (which Lufthansa states 

is extremely improbable due to the fact 

that a simultaneous double failure has 

to exist). With the above-mentioned 

overhaul and an additional maintenance 

task, Lufthansa states that it is reducing 

if not even excluding the risk of a 

double failure. Lufthansa requests a 

compliance time of 8 years for the first 

D-check, 8 years for the second D-check, 

and 6 years for subsequent D-checks. 

We do not agree with the commenter’s 

request to include an optional method 

of compliance. Based on the results of 

Boeing’s extensive testing of carbon disk 

brakes, the carbon brakes may be 

ineffective regardless of wear. Therefore, 

overhauling the carbon brakes at Dcheck intervals would not adequately 

address the unsafe condition. In 

addition, we do not consider that the 

brake system failure—which involves a 

latent failure of the no-back brake, 

combined with an active failure of the 

flap drive system—is extremely 

improbable. No change to this AD is 

necessary. 

Request to Delay Issuing Final Rule 

Japan Airlines (JAL) requests that we 

issue the AD after Revision 1 of Boeing 

Service Bulletin 747–27–2422 is 

available. The NPRM cited Boeing 

Special Attention Service Bulletin 747– 

27–2422, dated October 30, 2008, as the 

appropriate source of service 

information for installing the skewed 

roller no-back brakes at the trailing edge 

flap transmission. JAL requests that 

Boeing amend Service Bulletin 747–27– 

2422 to improve Figure 3 to show part 

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