Federal Register / Vol. 75, No. 126 / Thursday, July 1, 2010 / Rules and Regulations 38001 

(AWLs) and Certification Maintenance 

Requirements (CMRs), Document D6–13747– 

CMR, Revision March 2008. (This AWL was 

first introduced in Revision September 2007 

of the AWLs/CMRs document.) Incorporating 

AWL 28–AWL–23 in accordance with 

paragraph (g) of AD 2008–10–07, 

Amendment 39–15513; or AD 2008–10–07 

R1, Amendment 39–16070; is acceptable for 

compliance with the corresponding 

requirements specified in this paragraph. 

No Alternative Inspection or Inspection 

Intervals 

(i) After accomplishing the actions 

required by paragraph (h) of this AD, no 

alternative inspections or inspection 

intervals may be used, unless the inspections 

or intervals are approved as an alternative 

method of compliance (AMOC) in 

accordance with the procedures specified in 

paragraph (k) of this AD. 

Credit for Actions Done Using Previous 

Service Information 

(j) Incorporating new AWLs 28–AWL–28 

and 28–AWL–29 of Subsection D, 

‘‘AIRWORTHINESS LIMITATIONS—FUEL 

SYSTEMS,’’ of Boeing 747–400 Maintenance 

Planning Data (MPD) Document, Document 

D621U400–9, Section 9, Revision April 2008; 

or Revision March 2009; before the effective 

date of this AD is acceptable for compliance 

with the requirements of paragraph (h)(1) of 

this AD. 

Alternative Methods of Compliance 

(AMOCs) 

(k)(1) The Manager, Seattle Aircraft 

Certification Office (ACO), 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: 

Georgios Roussos, Aerospace Engineer, 

Systems and Equipment Branch, ANM–130S, 

FAA, Seattle Aircraft Certification Office, 

1601 Lind Avenue SW., Renton, Washington 

98057–3356; telephone (425) 917–6482; fax 

(425) 917–6590. Information may be e-mailed 

to 9-ANM-Seattle-ACO-AMOCRequests@faa.gov. 

(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 

(l) 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 

Boeing Alert Service Bulletin 747-28A2261 .................................................................................. Original ....................... February 19, 2009 

Subsection D, ‘‘AIRWORTHINESS LIMITATIONS—SYSTEMS,’’ of Boeing 747-100/200/300/ 

SP Airworthiness Limitations (AWLs) and Certification Maintenance Requirements (CMRs), 

Document D6-13747–CMR.

March 2008 ................. March 2008 

Subsection D, ‘‘AIRWORTHINESS LIMITATIONS—FUEL SYSTEMS,’’ of Section 9 of the 

Boeing 747-400 Maintenance Planning Data (MPD) Document, Document D621U400–9.

December 2009 .......... December 2009 

(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 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. 

(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. 

(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. 

Issued in Renton, Washington, on June 10, 

2010. 

Jeffrey E. Duven, 

Acting Manager, Transport Airplane 

Directorate, Aircraft Certification Service. 

[FR Doc. 2010–15651 Filed 6–30–10; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2008–0981; Directorate 

Identifier 2008–NM–073–AD; Amendment 

39–16352; AD 2010–14–07] 

RIN 2120–AA64 

Airworthiness Directives; The Boeing 

Company Model 747 Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), Department of 

Transportation (DOT). 

ACTION: Final rule. 

SUMMARY: The FAA is superseding an 

existing airworthiness directive (AD), 

which applies to certain Model 747 

airplanes. That AD currently requires 

repetitive inspections of the body 

station (BS) 2598 bulkhead, and 

corrective actions if necessary. That AD 

also currently requires a terminating 

modification for certain repetitive 

inspections and a post-modification 

inspection of the modified area. This 

new AD continues to require those 

actions using revised service 

information. For certain airplanes, this 

AD requires new repetitive inspections, 

an interim modification, and postinterim modification inspections. For 

certain airplanes, this AD requires 

replacing any previously repaired aft 

inner chord and reinstalling the 

terminating modification. For airplanes 

that are converted to the Model 747–400 

large cargo freighter (LCF) configuration, 

this new AD reduces the threshold and 

repeat intervals of certain postmodification inspections. For all 

airplanes, this new AD also requires 

certain inspections of the upper aft 

outer chords and diagonal brace 

attachment fittings, flanges, and rods to 

continue after the terminating 

modification. This AD results from 

reports of cracked aft inner chords on 

airplanes after certain requirements of 

the existing AD were done. We are 

issuing this AD to prevent fatigue 

cracking of the BS 2598 bulkhead 

structure, which could result in 

inability of the structure to carry 

horizontal stabilizer flight loads, and 

loss of controllability of the airplane. 

DATES: This AD becomes effective 

August 5, 2010. 

The Director of the Federal Register 

approved the incorporation by reference 

of certain publications listed in the AD 

as of August 5, 2010. 

On April 13, 2006 (71 FR 12125, 

March 9, 2006), the Director of the 

Federal Register approved the 

incorporation by reference of certain 

other publications listed in the AD. 

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38002 Federal Register / Vol. 75, No. 126 / Thursday, July 1, 2010 / Rules and Regulations 

On October 27, 2003 (68 FR 54990, 

September 22, 2003), the Director of the 

Federal Register approved the 

incorporation by reference of a certain 

other publication listed in the AD. 

On August 16, 2001 (66 FR 36443, 

July 12, 2001), the Director of the 

Federal Register approved the 

incorporation by reference of a certain 

other publication listed in the AD. 

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: Ivan 

Li, Aerospace Engineer, Airframe 

Branch, ANM–120S, FAA, Seattle 

Aircraft Certification Office, 1601 Lind 

Avenue, SW., Renton, Washington 

98057–3356; telephone (425) 917–6437; 

fax (425) 917–6590. 

SUPPLEMENTARY INFORMATION: 

Discussion 

The FAA issued a supplemental 

notice of proposed rulemaking (NPRM) 

to amend 14 CFR part 39 to include an 

AD that supersedes AD 2006–05–06, 

Amendment 39–14503 (71 FR 12125, 

March 9, 2006). The existing AD applies 

to certain Model 747 airplanes. That 

supplemental NPRM was published in 

the Federal Register on February 24, 

2010 (75 FR 8279). That supplemental 

NPRM proposed to continue to require 

repetitive inspections of the body 

station (BS) 2598 bulkhead, and 

corrective actions if necessary; and a 

terminating modification for the 

repetitive inspections and a postmodification inspection of the modified 

area; using revised service information. 

For certain airplanes, the supplemental 

NPRM proposed to require new 

repetitive inspections, an interim 

modification, and post-interim 

modification inspections. For certain 

airplanes, the supplemental NPRM also 

proposed to require replacing any 

previously repaired aft inner chord and 

reinstalling the terminating 

modification. The supplemental NPRM 

proposed to reduce the threshold and 

repeat intervals of certain postmodification inspections for airplanes 

that are converted to the Model 747–400 

large cargo freighter (LCF) configuration. 

For all airplanes, the supplemental 

NPRM proposed that certain inspections 

of the upper aft outer chords and 

diagonal brace attachment fittings, 

flanges, and rods continue after the 

terminating modification. 

Comments 

We provided the public the 

opportunity to participate in the 

development of this AD. We have 

considered the comments that have 

been received on the supplemental 

NPRM. 

Support for the Supplemental NPRM 

Boeing concurs with the contents of 

the supplemental NPRM. 

Request To Delay the AD Pending 

Revised Service Information 

All Nippon Airways requests that we 

delay issuing the AD until Boeing 

revises Service Bulletin 747–53A2427 to 

Revision 6 (we referred to Boeing 

Service Bulletin 747–53A2427, Revision 

5, dated October 1, 2009, in the 

supplemental NPRM as the appropriate 

source of service information for certain 

actions). All Nippon Airways explains 

that it has asked Boeing to clarify an 

alternate material and filler thickness, 

which it asserts were not reflected in 

Boeing Service Bulletin 747–53A2427, 

Revision 5, dated October 1, 2009. All 

Nippon Airways also state that Boeing 

will make the necessary changes in 

Revision 6 of Boeing Service Bulletin 

747–53A2427. All Nippon Airways 

states that not including this 

information in the AD will be a burden 

on operators, causing them to request 

alternative methods of compliance 

(AMOCs) once the supplemental NPRM 

is mandated. 

We do not agree to delay this AD until 

additional service information is issued. 

We do not consider that further delaying 

this action until after the release of the 

manufacturer’s planned service bulletin 

is warranted, since sufficient 

information currently exists to 

accomplish the applicable required 

actions within the specified compliance 

time. However, under the provisions of 

paragraph (x) of the final rule, we will 

consider requests for approval of an 

AMOC if sufficient data are submitted to 

substantiate that the change would 

provide an acceptable level of safety. 

We have not changed the AD in this 

regard. 

Request for Clarification of Certain 

Requirements 

Japan Airlines requests that we clarify 

the requirements specified in paragraph 

(q)(2)(ii) of the supplemental NPRM. 

Japan Airlines states that the inspection 

description specified in that paragraph 

is not clear, because Boeing Alert 

Service Bulletin 747–53A2473, Revision 

2, dated August 28, 2009, contains many 

inspections. Therefore, Japan Airlines 

suggests that we use the same wording 

between the supplemental NPRM and 

the service information, that we add the 

table number containing the 

requirement in the service information 

into the supplemental NPRM, and that 

we more clearly state the purpose of the 

inspection in the supplemental NPRM. 

We recognize that the actions 

specified in Boeing Alert Service 

Bulletin 747–53A2473, Revision 2, 

dated August 28, 2009, and this AD are 

complex. We point out that the wording 

used in this AD was taken directly from 

Boeing Alert Service Bulletin 747– 

53A2473, Revision 2, dated August 28, 

2009. Operators should note that 

paragraph (q)(2)(ii) of this AD must be 

read in concert with paragraph (q)(2) of 

this AD. The content of paragraph 

(q)(2)(ii) of this AD was meant to clarify 

the content of paragraph (q)(2) of this 

AD, which contains more detailed 

information. However, while there is no 

table number to associate with the 

requirements specified in paragraph 

(q)(2)(ii) of this AD, we can refer to the 

specific paragraph(s) of the 

Accomplishment Instructions of the 

service information, which contain the 

required actions. We have revised 

paragraphs (q)(2)(i) and (q)(2)(ii) of this 

AD to specify the applicable paragraph 

of the Accomplishment Instructions of 

Boeing Alert Service Bulletin 747– 

53A2473, Revision 2, dated August 28, 

2009, for accomplishing the required 

actions specified in those paragraphs. 

Because the purpose of the inspection 

provided in paragraph (q)(2)(ii) of this 

AD is provided in paragraph (q)(2) of 

this AD, we find that no additional 

clarification is necessary in that regard. 

Conclusion 

We have carefully reviewed the 

available data, including the comments 

that have been received, and determined 

that air safety and the public interest 

require adopting the AD with the 

changes described previously. We have 

determined that these changes will 

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neither increase the economic burden 

on any operator nor increase the scope 

of the AD. 

Explanation of Change to Costs of 

Compliance 

Since issuance of the supplemental 

NPRM, we have increased the labor rate 

used in the Costs of Compliance from 

$80 per work-hour to $85 per workhour. The Costs of Compliance 

information, below, reflects this 

increase in the specified hourly labor 

rate. 

Costs of Compliance 

There are about 998 airplanes of the 

affected design in the worldwide fleet. 

The following table provides the 

estimated costs for U.S. operators to 

comply with this AD. The average labor 

rate is $85 per work hour. 

TABLE—ESTIMATED COSTS OF COMPLIANCE

Action Work 

hours Parts Cost per airplane 

Number of 

U.S.-registered 

airplanes 

Fleet cost 

Surface high frequency 

eddy current (HFEC) inspections (required by 

AD 2006–05–06) and 

open-hole HFEC inspections (new required action).

2 None .................................. $170, per inspection cycle 162 $27,540, per inspection 

cycle. 

Detailed inspections (required by AD 2006–05– 

06).

2 None .................................. 170, per inspection cycle .. 162 27,540, per inspection 

cycle. 

Terminating modification 

(partially required by AD 

2006–05–06; additional 

modification requirements in this new action).

126 $52,218 ............................. 62,928 ............................... 162 10,194,336 

Interim modification (new 

required action).

4 $4,000 ............................... 4,340 ................................. 162 703,080 

Replacement of previously 

repaired aft inner chords 

(new required action).

2 None .................................. 170 .................................... 162 27,540 

Support Frame upper Corner Fastener Inspection 

(new required action).

8 None .................................. 680 .................................... 162 110,160 

Post-modification inspection (new required action).4 None .................................. 340 .................................... 162 55,080 

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 have determined that 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. 

We prepared a regulatory evaluation 

of the estimated costs to comply with 

this AD and placed it in the AD docket. 

See the ADDRESSES section for a location 

to examine the regulatory evaluation. 

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 Federal Aviation 

Administration (FAA) amends § 39.13 

by removing Amendment 39–14503 (71 

FR 12125, March 9, 2006) and by adding 

the following new airworthiness 

directive (AD): 

2010–14–07 The Boeing Company: 

Amendment 39–16352. Docket No. 

FAA–2008–0981; Directorate Identifier 

2008–NM–073–AD. 

Effective Date 

(a) This AD becomes effective August 5, 

2010. 

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38004 Federal Register / Vol. 75, No. 126 / Thursday, July 1, 2010 / Rules and Regulations 

Affected ADs 

(b) This AD supersedes AD 2006–05–06, 

Amendment 39–14503. 

Applicability 

(c) This AD applies to The Boeing 

Company Model 747–100, 747–100B, 747– 

100B SUD, 747–200B, 747–200C, 747–200F, 

747–300, 747–400, 747–400D, 747–400F, 

747SR, and 747SP series airplanes, 

certificated in any category, line numbers 1 

though 1307 inclusive. 

Subject 

(d) Air Transport Association (ATA) of 

America Code 53: Fuselage. 

Unsafe Condition 

(e) This AD results from reports of cracked 

aft inner chords on airplanes after certain 

requirements of the existing AD were done. 

We are issuing this AD to prevent fatigue 

cracking of the body station (BS) 2598 

bulkhead structure, which could result in 

inability of the structure to carry horizontal 

stabilizer flight loads, and loss of 

controllability 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. 

Restatement of Requirements of AD 2006– 

05–06 

Repetitive High Frequency Eddy Current 

(HFEC) Inspections of the Bulkhead Frame 

Supports 

(g) Before the accumulation of 10,000 total 

flight cycles, or within 1,000 flight cycles 

after August 16, 2001 (the effective date of 

AD 2001–14–07, Amendment 39–12318, 

which was superseded by AD 2006–05–06), 

whichever occurs later: Do an open-hole 

HFEC inspection to find cracking of the 

bulkhead frame support under the hinge 

support fittings of the horizontal stabilizer on 

the left and right sides at BS 2598, in 

accordance with Figure 2 of the 

Accomplishment Instructions of Boeing 

Service Bulletin 747–53A2449, Revision 1, 

dated May 24, 2001; or Revision 2, dated 

March 14, 2002. Repeat the inspection after 

that at intervals not to exceed 3,000 flight 

cycles. Inspections accomplished before 

August 16, 2001, per Boeing Alert Service 

Bulletin 747–53A2449, dated June 8, 2000, 

are considered acceptable for compliance 

with the applicable inspection specified in 

this paragraph. 

Repair of Any Cracked Bulkhead Frame 

Support 

(h) If any cracking is found during any 

inspection required by paragraph (g) of this 

AD, before further flight, repair using a 

method approved in accordance with the 

procedures specified in paragraph (x) of this 

AD. 

Repetitive Inspections of Inner Chords, 

Frame Support Fitting, and Splice Fitting 

(i) Do a surface HFEC inspection of the 

forward and aft inner chords, the frame 

support, and the splice fitting of the forward 

inner chord of the upper corners of the 

station 2598 bulkhead to find cracking, in 

accordance with the Accomplishment 

Instructions of Boeing Alert Service Bulletin 

747–53A2427, Revision 2, dated October 5, 

2000; Revision 3, dated September 27, 2001; 

or Boeing Service Bulletin 747–53A2427, 

Revision 5, dated October 1, 2009; at the 

latest of the times specified in paragraphs 

(i)(1) and (i)(2) of this AD, as applicable. 

Repeat the inspection after that at intervals 

not to exceed 1,500 flight cycles. After the 

effective date of this AD, Boeing Service 

Bulletin 747–53A2427, Revision 5, dated 

October 1, 2009, must be used. 

(1) For airplanes having line numbers 1 

through 1241 inclusive: 

(i) Before the accumulation of 6,000 total 

flight cycles. 

(ii) Within 500 flight cycles after August 

28, 2001 (the effective date of AD 2001–15– 

03, Amendment 39–12337, which was 

superseded by AD 2006–05–06). 

(iii) For airplanes inspected before August 

28, 2001, in accordance with Boeing Alert 

Service Bulletin 747–53A2427, dated 

December 17, 1998 (including inspections of 

the splice fitting); or Revision 1, dated 

October 28, 1999: Within 1,500 flight cycles 

after accomplishment of the last inspection 

done in accordance with the original service 

bulletin or Revision 1, as applicable. 

(2) For airplanes having line numbers 1242 

through 1307 inclusive: 

(i) Before the accumulation of 16,000 total 

flight cycles. 

(ii) Within 500 flight cycles after August 

28, 2001. 

(iii) For airplanes inspected before August 

28, 2001, in accordance with Boeing Alert 

Service Bulletin 747–53A2427, dated 

December 17, 1998 (including inspections of 

the splice fitting), or Revision 1, dated 

October 28, 1999: Within 1,500 flight cycles 

after accomplishment of the last inspection 

done in accordance with Boeing Alert 

Service Bulletin 747–53A2427, dated 

December 17, 1998; or Revision 1, dated 

October 28, 1999; as applicable. 

Repair of Any Cracked Inner Chord, Frame 

Support, or Splice Fitting 

(j) If any cracking is found during the 

inspections required by paragraph (i) of this 

AD, before further flight, repair in accordance 

with the Accomplishment Instructions of 

Boeing Alert Service Bulletin 747–53A2427, 

Revision 2, dated October 5, 2000; Revision 

3, dated September 27, 2001; or Boeing 

Service Bulletin 747–53A2427, Revision 5, 

dated October 1, 2009. After the effective 

date of this AD, Boeing Service Bulletin 747– 

53A2427, Revision 5, dated October 1, 2009, 

must be used. Where Boeing Alert Service 

Bulletin 747–53A2427, Revision 2, dated 

October 5, 2000; Revision 3, dated September 

27, 2001; or Boeing Service Bulletin 747– 

53A2427, Revision 5, dated October 1, 2009; 

specifies that the manufacturer may be 

contacted for disposition of certain repair 

conditions, before further flight, repair using 

a method approved in accordance with the 

procedures specified in paragraph (x) of this 

AD. 

Repetitive Detailed Inspections of BS 2598 

Bulkhead 

(k) Before the accumulation of 10,000 total 

flight cycles, or within 1,000 flight cycles 

after October 27, 2003 (the effective date of 

AD 2003–19–08, Amendment 39–13311, 

which was superseded by AD 2006–05–06), 

whichever is later: Do a detailed inspection 

of the BS 2598 bulkhead for discrepancies 

(cracking, elongated fastener holes) of the 

areas specified in paragraphs (k)(1) and (k)(2) 

of this AD, in accordance with the 

Accomplishment Instructions of Boeing Alert 

Service Bulletin 747–53A2467, dated July 26, 

2001; or Boeing Service Bulletin 747– 

53A2467, Revision 1, dated April 28, 2005. 

Repeat the inspections after that at intervals 

not to exceed 3,000 flight cycles, except as 

required by paragraph (m) of this AD. Doing 

the modification specified in paragraph (m) 

or (q) of this AD terminates the inspection of 

the area specified in paragraph (k)(1) of this 

AD. 

(1) The lower aft inner chords. 

(2) The upper aft outer chords, and the 

diagonal brace attachment fittings, flanges, 

and rods. 

Note 1: For the purposes of this AD, a 

detailed inspection is ‘‘an intensive 

examination of a specific item, installation, 

or assembly to detect damage, failure, or 

irregularity. Available lighting is normally 

supplemented with a direct source of good 

lighting at an intensity deemed appropriate. 

Inspection aids such as mirrors magnifying 

lenses, etc. may be necessary. Surface 

cleaning and elaborate procedures may be 

required.’’ 

Repair of Any Cracked BS 2598 Bulkhead 

(l) If any discrepancy is found during any 

inspection required by paragraph (k) of this 

AD: Before further flight, repair in 

accordance with the Accomplishment 

Instructions of Boeing Alert Service Bulletin 

747–53A2467, dated July 26, 2001; or Boeing 

Service Bulletin 747–53A2467, Revision 1, 

dated April 28, 2005. If Boeing Alert Service 

Bulletin 747–53A2467, dated July 26, 2001; 

or Boeing Service Bulletin 747–53A2467, 

Revision 1, dated April 28, 2005; specifies to 

contact Boeing for appropriate action: Before 

further flight, repair using a method 

approved in accordance with the procedures 

specified in paragraph (x) of this AD. 

Terminating Modification With New 

Compliance Time for Certain Airplanes for 

the Inspection Specified in Paragraph (k)(2) 

of This AD 

(m) Except as provided by paragraph (q) of 

this AD: Before the accumulation of 20,000 

total flight cycles, or within 48 months after 

April 13, 2006 (the effective date of AD 

2006–05–06), whichever occurs later, modify 

the bulkhead by doing all applicable actions 

including surface and open-hole HFEC 

inspections for cracking of the upper forward 

inner chords, aft inner chords, upper splice 

fittings, and frame support fittings, as 

specified in the Accomplishment 

Instructions of Boeing Service Bulletin 747– 

53–2473, dated March 24, 2005; Revision 1, 

dated February 20, 2007; or Boeing Alert 

Service Bulletin 747–53A2473, Revision 2, 

dated August 28, 2009. Repair any cracks 

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before further flight, in accordance with 

Boeing Service Bulletin 747–53–2473, dated 

March 24, 2005; Revision 1, dated February 

20, 2007; or Boeing Alert Service Bulletin 

747–53A2473, Revision 2, dated August 28, 

2009. Where Boeing Service Bulletin 747– 

53–2473, dated March 24, 2005; Revision 1, 

dated February 20, 2007; or Boeing Alert 

Service Bulletin 747–53A2473, Revision 2, 

dated August 28, 2009; specifies that the 

manufacturer may be contacted for 

disposition of certain repair conditions: 

Before further flight, repair the cracks using 

a method approved in accordance with the 

procedures specified in paragraph (x) of this 

AD. Accomplishment of the modification 

terminates the requirements of paragraphs 

(g), (i), and (k)(1) of this AD. After the 

effective date of this AD, Boeing Alert 

Service Bulletin 747–53A2473, Revision 2, 

dated August 28, 2009, must be used for the 

actions specified in this paragraph. For 

airplanes that are converted to the Model 

747–400 Large Cargo Freighter (LCF) 

configuration, repeat the inspection specified 

in paragraph (k)(2) of this AD thereafter at 

intervals not to exceed 1,800 flight cycles. 

Post-Modification Inspection and Repair 

(n) Except as provided by paragraphs (q) 

and (r) of this AD: Within 20,000 flight cycles 

after doing the modification required by 

paragraph (m) of this AD, inspect the BS 

2598 bulkhead for cracks, and repair any 

cracks before further flight, in accordance 

with a method approved by the Manager, 

Seattle Aircraft Certification Office (ACO). 

New Requirements of This AD 

Terminating Repair for Repetitive Surface 

HFEC Inspections 

(o) As of the effective date of this AD, 

accomplishing the aft inner chord repair 

required by paragraph (j) of this AD in 

accordance with the Accomplishment 

Instructions of Boeing Service Bulletin 747– 

53A2427, Revision 5, dated October 1, 2009, 

ends the repetitive surface HFEC inspections 

required by paragraph (i) of this AD for that 

side of the bulkhead only. 

Replacement of Previously Repaired Aft 

Inner Chord and Reinstallation of 

Terminating Modification 

(p) For airplanes on which the terminating 

modification required by paragraph (m) of 

this AD has been done in accordance with 

Boeing Service Bulletin 747–53–2473, dated 

March 24, 2005: Within 1,500 flight cycles 

after doing the modification, or within 1,000 

flight cycles after the effective date of this 

AD, whichever occurs later, do a one-time 

general visual inspection for repairs installed 

previously on the left and right side aft inner 

chords. For airplanes with previously 

installed repairs, before further flight, do 

rework (i.e., replace any previously repaired 

aft inner chord with a new aft inner chord 

and reinstall the terminating modification), 

using a method approved in accordance with 

the procedures specified in paragraph (x) of 

this AD. 

Revised Terminating Modification 

(q) Doing the applicable modification 

required by paragraph (q)(1) or (q)(2) of this 

AD at the applicable time terminates the 

requirements of paragraph (m) of this AD and 

the repetitive inspections required by 

paragraphs (g), (i), and (k)(1) of this AD. For 

airplanes that are converted to the Model 

747–400 LCF configuration, the inspection 

specified in paragraph (k)(2) of this AD must 

be repeated thereafter at intervals not to 

exceed 1,800 flight cycles. 

(1) For airplanes on which the terminating 

modification required by paragraph (m) of 

this AD has not been done as of the effective 

date of this AD: Before the accumulation of 

20,000 total flight cycles, or within 18 

months after the effective date of this AD, 

whichever occurs later, modify the bulkhead, 

in accordance with the Accomplishment 

Instructions of Boeing Alert Service Bulletin 

747–53A2473, Revision 2, dated August 28, 

2009; except that where Boeing Alert Service 

Bulletin 747–53A2473, Revision 2, dated 

August 28, 2009, specifies to contact Boeing 

for modification data, the modification data 

must be approved in accordance with the 

procedures specified in paragraph (x) of this 

AD, and the modification must be done 

within the times specified in this paragraph. 

(2) For airplanes on which the terminating 

modification required by paragraph (m) of 

this AD has been done in accordance with 

Boeing Service Bulletin 747–53–2473, dated 

March 24, 2005; or Revision 1, dated 

February 20, 2007; as of the effective date of 

this AD: Within 1,000 flight cycles after the 

effective date of this AD, or within 1,500 

flight cycles after doing the modification, 

whichever occurs later, do a general visual 

inspection of the applicable areas specified 

in paragraph (q)(2)(i) and (q)(2)(ii) of this AD 

to determine if certain fasteners are installed, 

and, before further flight, do all applicable 

related investigative and corrective actions, 

in accordance with the Accomplishment 

Instructions of Boeing Alert Service Bulletin 

747–53A2473, Revision 2, dated August 28, 

2009; except where Boeing Alert Service 

Bulletin 747–53A2473, Revision 2, dated 

August 28, 2009, specifies to contact Boeing 

for repair or rework data, the data must be 

approved in accordance with the procedures 

specified in paragraph (x) of this AD and the 

repair or rework must be done before further 

flight. 

(i) For airplanes modified in accordance 

with Boeing Service Bulletin 747–53–2473, 

dated March 24, 2005: Inspect the upper 

forward inner chord, frame support fitting, 

and splice fitting, in accordance with 

paragraph 3.B.7.d. of the Accomplishment 

Instructions of Boeing Alert Service Bulletin 

747–53A2473, Revision 2, dated August 28, 

2009. 

(ii) For airplanes modified in accordance 

with Boeing Service Bulletin 747–53–2473, 

Revision 1, dated February 20, 2007: Inspect 

the frame web and upper shear deck aft side, 

and the upper forward inner chord, frame 

support fitting, and splice fitting, in 

accordance with paragraphs 3.B.7.c and 

3.B.7.d of the Accomplishment Instructions 

of Boeing Alert Service Bulletin 747– 

53A2473, Revision 2, dated August 28, 2009. 

Post-Modification Inspection and Repair 

(r) For airplanes on which the terminating 

modification has been done in accordance 

with paragraph (m) or (q) of this AD: Perform 

post-modification inspections of the BS 2598 

bulkhead for cracking, in accordance with 

Parts 1, 2, and 3 of the Accomplishment 

Instructions of Boeing Alert Service Bulletin 

747–53A2473, Revision 2, dated August 28, 

2009. Do the inspections at the applicable 

times specified in Tables 6 through 9 of 

paragraph 1.E., ‘‘Compliance,’’ of Boeing Alert 

Service Bulletin 747–53A2473, Revision 2, 

dated August 28, 2009; except where Boeing 

Alert Service Bulletin 747–53A2473, 

Revision 2, dated August 28, 2009, specifies 

a compliance time after the date of that 

service bulletin, this AD requires compliance 

within the specified compliance time after 

the effective date of this AD. If any cracking 

is found during any inspection required by 

this paragraph, before further flight, repair 

using a method approved in accordance with 

the procedures specified in paragraph (x) of 

this AD. Repeat the inspections thereafter at 

the applicable times specified in Tables 6 

through 9 of paragraph 1.E., ‘‘Compliance,’’ of 

Boeing Alert Service Bulletin 747–53A2473, 

Revision 2, dated August 28, 2009. 

Accomplishing the applicable inspections 

required by this paragraph terminates the 

requirements of paragraph (n) of this AD. 

Open-Hole HFEC Inspection(s) and 

Terminating Repair 

(s) For airplanes on which the terminating 

modification required by paragraph (m) or (q) 

of this AD has not been done: Do an initial 

open-hole HFEC inspection to detect cracks 

in the bulkhead splice fitting, frame support 

fitting, and forward and aft inner chords on 

the left and right sides of the BS 2598 

bulkhead, in accordance with the 

Accomplishment Instructions of Boeing 

Service Bulletin 747–53A2427, Revision 5, 

dated October 1, 2009. Do the initial 

inspection at the applicable time specified in 

Table 1 or 3 of paragraph 1.E., ‘‘Compliance,’’ 

of Boeing Service Bulletin 747–53A2427, 

Revision 5, dated October 1, 2009; except 

where Boeing Service Bulletin 747–53A2427, 

Revision 5, dated October 1, 2009, specifies 

a compliance time after the date on that 

service bulletin, this AD requires compliance 

within the specified compliance time after 

the effective date of this AD. 

(1) If no crack is detected, repeat the openhole HFEC inspection thereafter at intervals 

not to exceed 1,500 flight cycles. 

(2) If any crack is detected, before further 

flight, repair it in accordance with the 

Accomplishment Instructions of Boeing 

Service Bulletin 747–53A2427, Revision 5, 

dated October 1, 2009; except where Boeing 

Service Bulletin 747–53A2427, Revision 5, 

dated October 1, 2009, specifies to contact 

Boeing for appropriate action, before further 

flight, repair the crack using a method 

approved in accordance with the procedures 

specified in paragraph (x) of this AD. 

Accomplishing the aft inner chord repair in 

accordance with the Accomplishment 

Instructions of Boeing Service Bulletin 747– 

53A2427, Revision 5, dated October 1, 2009, 

ends the repetitive surface and open-hole 

HFEC inspections required by paragraphs (i) 

and (s)(1), respectively, of this AD for that 

side of the bulkhead only. 

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38006 Federal Register / Vol. 75, No. 126 / Thursday, July 1, 2010 / Rules and Regulations 

Interim Modification 

(t) For Group 1 airplanes, as identified in 

Boeing Service Bulletin 747–53A2427, 

Revision 5, dated October 1, 2009, on which 

the repair required by paragraph (j) or (s)(2) 

of this AD has not been done; and on which 

the terminating modification required by 

paragraph (m) or (q) of this AD has not been 

done: Before the accumulation of 12,000 total 

flight cycles, or within 1,500 flight cycles 

after the effective date of this AD, whichever 

occurs later, install the interim modification 

for the aft inner chords, in accordance with 

the Accomplishment Instructions of Boeing 

Service Bulletin 747–53A2427, Revision 5, 

dated October 1, 2009. Accomplishing the 

interim modification ends the repetitive 

surface and open-hole HFEC inspections 

required by paragraphs (i) and (s)(1), 

respectively, of this AD. 

Post-Interim Modification/Repair Repetitive 

Surface and Open-Hole HFEC Inspections 

(u) For airplanes on which the interim 

modification required by paragraph (t) of this 

AD has been done or the repair required by 

paragraph (j) or (s)(2) of this AD has been 

done; and on which the terminating 

modification required by paragraph (m) or (q) 

of this AD has not been done: At the 

applicable times specified in Table 1, 2, or 

3 of paragraph 1.E., ‘‘Compliance,’’ of Boeing 

Service Bulletin 747–53A2427, Revision 5, 

dated October 1, 2009, do a surface HFEC 

inspection to detect cracks on the forward 

side (unmodified area) of the bulkhead, and 

open-hole and surface HFEC inspections to 

detect cracks in the modified or repaired 

area, in accordance with the 

Accomplishment Instructions of Boeing 

Service Bulletin 747–53A2427, Revision 5, 

dated October 1, 2009. Repeat the open-hole 

and surface HFEC inspections thereafter at 

intervals not to exceed 1,500 flight cycles, 

until the modification required by paragraph 

(q) of this AD is done, as applicable; except 

that for airplanes on which the repair of any 

cracked aft inner chord has been done on 

only one side of the bulkhead in accordance 

with the applicable requirements specified in 

paragraph (j) or (s)(2) of this AD, the 

repetitive surface and open-hole HFEC 

inspections required by paragraphs (i) and 

(s)(1), respectively, of this AD must continue 

to be done for the other side of the bulkhead. 

Repair of Any Cracked Inner Chord, Splice 

Fitting, or Frame Support Fitting 

(v) If any crack is detected during any 

surface or open-hole HFEC inspection 

required by paragraph (u) of this AD, before 

further flight, repair any cracked inner chord, 

splice fitting, or frame support fitting, in 

accordance with the Accomplishment 

Instructions of Boeing Service Bulletin 747– 

53A2427, Revision 5, dated October 1, 2009; 

except where Boeing Service Bulletin 747– 

53A2427, Revision 5, dated October 1, 2009, 

specifies to contact Boeing for appropriate 

action, before further flight, repair the crack 

using a method approved in accordance with 

the procedures specified in paragraph (x) of 

this AD. 

Actions Accomplished According to 

Previous Issue of Service Bulletin 

(w) Inspections, interim modification, and 

repairs accomplished before the effective 

date of this AD in accordance with Boeing 

Alert Service Bulletin 747–53A2427, 

Revision 4, dated March 6, 2008, are 

considered acceptable for compliance with 

the corresponding action specified 

paragraphs (i), (j), (s), (t), (u), and (v) of this 

AD. 

Alternative Methods of Compliance 

(AMOCs) 

(x)(1) The Manager, Seattle ACO, 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: Ivan 

Li, Aerospace Engineer, Airframe Branch, 

ANM–120S, FAA, Seattle ACO, 1601 Lind 

Avenue SW., Renton, Washington 98057– 

3356; telephone (425) 917–6437; fax (425) 

917–6590. Information may be e-mailed to: 9- 

ANM-Seattle-ACO-AMOC-Requests@faa.gov. 

(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. 

(3) An AMOC that provides an acceptable 

level of safety may be used for any repair 

required by this AD, if it is approved by 

Boeing Commercial Airplanes Organization 

Designation Authorization (ODA) that has 

been authorized by the Manager, Seattle 

ACO, to make those findings. For a repair 

method to be approved, the repair must meet 

the certification basis of the airplane, and the 

approval must specifically refer to this AD. 

(4) AMOCs approved previously in 

accordance with AD 2006–05–06 are 

approved as AMOCs for the corresponding 

provisions of this AD. 

Material Incorporated by Reference 

(y) You must use the service information 

contained in Table 1 of this AD, as 

applicable, to do the actions required by this 

AD, unless the AD specifies otherwise. 

TABLE 1—ALL MATERIAL INCORPORATED BY REFERENCE

Document Revision Date 

Boeing Alert Service Bulletin 747–53A2467 ........................................... Original .......................................... July 26, 2001. 

Boeing Alert Service Bulletin 747–53A2473 ........................................... 2 ..................................................... August 28, 2009. 

Boeing Service Bulletin 747–53A2427 .................................................... 5 ..................................................... October 1, 2009. 

Boeing Service Bulletin 747–53A2449 .................................................... 1 ..................................................... May 24, 2001. 

Boeing Service Bulletin 747–53A2449 .................................................... 2 ..................................................... March 14, 2002. 

Boeing Service Bulletin 747–53A2467 .................................................... 1 ..................................................... April 28, 2005. 

(1) The Director of the Federal Register 

approved the incorporation by reference of 

the service information contained in Table 2 

of this AD under 5 U.S.C. 552(a) and 1 CFR 

part 51. 

TABLE 2—NEW MATERIAL INCORPORATED BY REFERENCE

Document Revision Date 

Boeing Alert Service Bulletin 747–53A2473 ................................................................... 2 August 28, 2009. 

Boeing Service Bulletin 747–53A2427 ........................................................................... 5 October 1, 2009. 

(2) On April 13, 2006 (71 FR 12125, March 

9, 2006), the Director of the Federal Register 

approved the incorporation by reference of 

Boeing Service Bulletin 747–53A2449, 

Revision 2, dated March 14, 2002; and 

Boeing Service Bulletin 747–53A2467, 

Revision 1, dated April 28, 2005. 

(3) On October 27, 2003 (68 FR 54990, 

September 22, 2003), the Director of the 

Federal Register approved the incorporation 

by reference of Boeing Alert Service Bulletin 

747–53A2467, dated July 26, 2001. 

(4) On August 16, 2001 (66 FR 36443, July 

12, 2001), the Director of the Federal Register 

approved the incorporation by reference of 

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Federal Register / Vol. 75, No. 126 / Thursday, July 1, 2010 / Rules and Regulations 38007 

Boeing Service Bulletin 747–53A2449, 

Revision 1, dated May 24, 2001. 

(5) 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. 

(6) 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. 

(7) 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. 

Issued in Renton, Washington, on June 17, 

2010. 

Robert D. Breneman, 

Acting Manager, Transport Airplane 

Directorate, Aircraft Certification Service. 

[FR Doc. 2010–15654 Filed 6–30–10; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2010–0275; Directorate 

Identifier 2009–NM–231–AD; Amendment 

39–16344; AD 2010–14–01] 

RIN 2120–AA64 

Airworthiness Directives; The Boeing 

Company Model 747–100, 747–100B, 

747–100B SUD, 747–200B, 747–200C, 

747–200F, 747–300, 747–400, 747– 

400F, 747SR, and 747SP Series 

Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final rule. 

SUMMARY: We are adopting a new 

airworthiness directive (AD) for certain 

Model 747–100, 747–100B, 747–100B 

SUD, 747–200B, 747–200C, 747–200F, 

747–300, 747–400, 747–400F, 747SR, 

and 747SP series airplanes. This AD 

requires reworking or replacing certain 

duct assemblies in the environmental 

control system (ECS). This AD results 

from reports of duct assemblies in the 

ECS with burned Boeing Material 

Specification (BMS) 8–39 polyurethane 

foam insulation. This proposed AD also 

results from a report from the airplane 

manufacturer that airplanes were 

assembled with duct assemblies in the 

ECS wrapped with BMS 8–39 

polyurethane foam insulation, a 

material of which the fire retardant 

properties deteriorate with age. We are 

issuing this AD to prevent a potential 

electrical arc from igniting the BMS 8– 

39 polyurethane foam insulation on the 

duct assemblies of the ECS, which could 

propagate a small fire and lead to a 

larger fire that might spread throughout 

the airplane through the ECS. 

DATES: This AD is effective August 5, 

2010. 

The Director of the Federal Register 

approved the incorporation by reference 

of certain publications listed in the AD 

as of August 5, 2010. 

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: Sue 

McCormick, Aerospace Engineer, Cabin 

Safety and Environmental Systems 

Branch, ANM–150S, FAA, Seattle 

Aircraft Certification Office, 1601 Lind 

Avenue, SW., Renton, Washington 

98057–3356; telephone (303) 342–1082; 

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 Model 747–100, 747–100B, 747– 

100B SUD, 747–200B, 747–200C, 747– 

200F, 747–300, 747–400, 747–400F, 

747SR, and 747SP series airplanes. That 

NPRM was published in the Federal 

Register on April 12, 2010 (75 FR 

18446). That NPRM proposed to require 

reworking or replacing certain duct 

assemblies in the environmental control 

system (ECS). 

Comments 

We gave the public the opportunity to 

participate in developing this AD. We 

considered the comments received. The 

Boeing Company concurs with the 

contents of the NPRM, and Delta 

Airlines states that it is not affected by 

the NPRM. 

Conclusion 

We reviewed the relevant data, 

considered the comments received, and 

determined that air safety and the 

public interest require adopting the AD 

as proposed. 

Costs of Compliance 

There are about 558 airplanes of the 

affected design in the worldwide fleet. 

The average labor rate is $85 per workhour. The following table provides the 

estimated costs for U.S. operators to 

comply with this AD. 

ESTIMATED COSTS

Action Work hours Parts cost, per airplane Cost per airplane 

Number of 

U.S.-registered 

airplanes 

Fleet cost 

Duct assembly rework, 

specified in Boeing 

Service Bulletin 747– 

21A2421.

8 per duct (average of 

130 ducts per airplane).

$12,305 (average) .......... $100,705 (average) ... 185 ................... $18,630,425. 

Duct assembly rework or 

replacement, specified 

in Boeing Service Bulletin 747–21A2422.

1 per duct (1 duct per airplane).The manufacturer states 

that it will supply required parts to the operators at no cost.

$85 ............................ Up to 168 ......... Up to $14,280. 

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