Federal Register / Vol. 78, No. 45 / Thursday, March 7, 2013 / Proposed Rules 14731 

effective date of this AD, whichever occurs 

first; 

(iii) If the actuator has accumulated more 

than 8 years since new or overhaul, but does 

not have 8.5 years or more since new or 

overhaul: No later than accumulating 8.5 

years hours since new or overhaul; or 

(iv) If the actuator has 8.5 years or more 

since new or overhaul: Before further flight 

after the effective date of this AD. 

(g) Other FAA AD Provisions 

The following provisions also apply to this 

AD: 

(1) Alternative Methods of Compliance 

(AMOCs): The Manager, Standards 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: Doug Rudolph, Aerospace Engineer, 

FAA, Small Airplane Directorate, 901 Locust, 

Room 301, Kansas City, Missouri 64106; 

telephone: (816) 329–4059; fax: (816) 329– 

4090; email: doug.rudolph@faa.gov. 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 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, a federal 

agency may not conduct or sponsor, and a 

person is not required to respond to, nor 

shall a person be subject to a penalty for 

failure to comply with a collection of 

information subject to the requirements of 

the Paperwork Reduction Act unless that 

collection of information displays a current 

valid OMB Control Number. The OMB 

Control Number for this information 

collection is 2120–0056. Public reporting for 

this collection of information is estimated to 

be approximately 5 minutes per response, 

including the time for reviewing instructions, 

completing and reviewing the collection of 

information. All responses to this collection 

of information are mandatory. Comments 

concerning the accuracy of this burden and 

suggestions for reducing the burden should 

be directed to the FAA at: 800 Independence 

Ave. SW., Washington, DC 20591, Attn: 

Information Collection Clearance Officer, 

AES–200. 

(h) Related Information 

Refer to MCAI EASA AD No.: 2012–0268, 

dated December 19, 2012; Chapter 04–00–00, 

Pilatus PC–6 B2–H2/B2–H4 Airplane 

Maintenance Manual (AMM); and, Pilatus 

PC–6 Airworthiness Limitations, Document 

No. 02334, Revision No. 3, dated July 31, 

2012; for related information. For service 

information related to this AD, contact 

Pilatus Aircraft Ltd., Customer Service 

Manager, CH–6371 STANS, Switzerland; 

telephone: +41 (0) 41 619 65 01; fax: +41 (0) 

41 619 65 76; Internet: http://www.pilatusaircraft.com/#32. You may review copies of 

the referenced service information at the 

FAA, Small Airplane Directorate, 901 Locust, 

Kansas City, Missouri 64106. For information 

on the availability of this material at the 

FAA, call (816) 329–4148. 

Issued in Kansas City, Missouri, on March 

1, 2013. 

John Colomy, 

Acting Manager, Small Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. 2013–05292 Filed 3–6–13; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2013–0204; Directorate 

Identifier 2012–NM–229–AD] 

RIN 2120–AA64 

Airworthiness Directives; The Boeing 

Company 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 

The Boeing Company Model 747–400 

and 747–400F series airplanes. This 

proposed AD was prompted by reports 

of cracking in the outboard flange of the 

longeron extension fittings, which 

attach to the wing-to-body fairing 

support frame. This proposed AD would 

require repetitive inspections of the 

longeron extension fittings for cracking, 

and corrective actions if necessary. We 

are proposing this AD to detect and 

correct cracks in the longeron extension 

fittings, which can become large and 

adversely affect the structural integrity 

of the airplane. 

DATES: We must receive comments on 

this proposed AD by April 22, 2013. 

ADDRESSES: You may send comments, 

using the procedures found in 14 CFR 

11.43 and 11.45, 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: Deliver to Mail 

address above between 9 a.m. and 5 

p.m., Monday through Friday, except 

Federal holidays. 

For Boeing service information 

identified in this proposed AD, contact 

Boeing Commercial Airplanes, 

Attention: Data & Services Management, 

P.O. Box 3707, MC 2H–65, Seattle, WA 

98124–2207; telephone 206–544–5000, 

extension 1; fax 206–766–5680; 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. 

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 

(phone: 800–647–5527) is in the 

ADDRESSES section. Comments will be 

available in the AD docket shortly after 

receipt. 

FOR FURTHER INFORMATION CONTACT: 

Nathan Weigand, Aerospace Engineer, 

Airframe Branch, ANM–120S, FAA, 

Seattle Aircraft Certification Office, 

1601 Lind Avenue SW., Renton, 

Washington 98057–3356; phone: 425– 

917–6428; fax: 425–917–6590; email: 

Nathan.P.Weigand@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

We invite you to send any written 

relevant data, views, or arguments about 

this proposal. Send your comments to 

an address listed under the ADDRESSES

section. Include ‘‘Docket No. FAA– 

2013–0204; Directorate Identifier 2012– 

NM–229–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 

We received reports that cracks were 

found in the outboard flanges of the 


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longeron extension fittings installed on 

the left and right sides of the airplane. 

Longeron extension fittings are installed 

on the fuselage under the wing-to-body 

fairing and attach the overwing longeron 

to the fuselage. The outboard flange of 

the fitting attaches to the wing-to-body 

fairing support frame web. Subsequent 

analysis by Boeing indicated that the 

cracks were caused by fatigue combined 

with preload stress from improper fit-up 

during assembly. A manufacturing 

process change that began at line 

number 1199 might have resulted in 

preloading the longeron extension 

fittings. We are proposing this AD to 

detect and correct cracks in the longeron 

extension fittings, which can become 

large and adversely affect the structural 

integrity of the airplane. 

Relevant Service Information 

We reviewed Boeing Alert Service 

Bulletin 747–53A2860, dated December 

4, 2012. For information on the 

procedures and compliance times, see 

this service information at http:// 

www.regulations.gov by searching for 

Docket No. FAA–2013–0204. 

FAA’s Determination 

We are proposing this AD because we 

evaluated all the relevant information 

and determined the unsafe condition 

described previously is likely to exist or 

develop in other products of the same 

type design. 

Proposed AD Requirements 

This proposed AD would require 

accomplishing the actions specified in 

the service information described 

previously, except as discussed under 

‘‘Differences Between the Proposed AD 

and the Service Information.’’ 

The phrase ‘‘related investigative 

actions’’ might be used in this proposed 

AD. ‘‘Related investigative actions’’ are 

follow-on actions that (1) are related to 

the primary action, and (2) are actions 

that further investigate the nature of any 

condition found. Related investigative 

actions in an AD could include, for 

example, inspections. 

In addition, the phrase ‘‘corrective 

actions’’ might be used in this proposed 

AD. ‘‘Corrective actions’’ are actions 

that correct or address any condition 

found. Corrective actions in an AD 

could include, for example, repairs. 

Differences Between the Proposed AD 

and the Service Information 

This proposed AD includes airplanes 

that are not included in the effectivity 

of Boeing Alert Service Bulletin 747– 

53A2860, dated December 4, 2012. That 

service bulletin defines actions for 

airplanes having line numbers 1199 

through 1419 inclusive. Boeing recently 

reported an event that involved a 

cracked longeron extension fitting on 

the airplane having line number 1101. 

Based on this event we are expanding 

the airplane applicability in this 

proposed AD from airplanes having line 

numbers 1199 through 1419 inclusive to 

airplanes having line numbers 1076 

through 1419 inclusive. We have 

coordinated this difference with Boeing. 

Although Boeing Alert Service 

Bulletin 747–53A2860, dated December 

4, 2012, specifies that operators may 

contact the manufacturer for the 

disposition of certain repair conditions, 

this proposed AD would require 

repairing those conditions in one of the 

following ways: 

• In accordance with a method that 

we approve; or 

• Using data that meet the 

certification basis of the airplane, and 

that have been approved by the Boeing 

Commercial Airplanes Organization 

Designation Authorization (ODA) whom 

we have authorized to make those 

findings. 

Costs of Compliance 

We estimate that this proposed AD 

affects 41 airplanes of U.S. registry. 

We estimate the following costs to 

comply with this proposed AD: 

ESTIMATED COSTS

Action Labor cost Parts cost Cost per 

product Cost on U.S. operators 

High frequency eddy current inspection for cracking in longeron 

extension fittings.

32 work-hours × $85 per hour = 

$2,720, per inspection cycle.

$0 $2,720 $111,520, per inspection cycle. 

Option to do preventative modification instead of repetitive inspections.479 work-hours × $85 per hour = 

$40,715.

0 40,715 $1,669,315. 

We estimate the following costs to do 

any necessary replacements that would 

be required based on the results of the 

proposed inspection. We have no way of 

determining the number of aircraft that 

might need this replacement: 

ON-CONDITION COSTS

Action Labor cost Parts cost Cost per 

product 

Replacement .................................... 464 work-hours × $85 per hour = $39,440 ............................................... $0 $39,440 

We have received no definitive data 

that would enable us to provide cost 

estimates for the on-condition actions 

specified in this proposed AD. 

According to the manufacturer, some 

of the costs of this proposed AD may be 

covered under warranty, thereby 

reducing the cost impact on affected 

individuals. We do not control warranty 

coverage for affected individuals. As a 

result, we have included all costs in our 

cost estimate. 

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 


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Federal Register / Vol. 78, No. 45 / Thursday, March 7, 2013 / Proposed Rules 14733 

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), 

(3) Will not affect intrastate aviation 

in Alaska, and 

(4) 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. 

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 airworthiness 

directive (AD): 

The Boeing Company: Docket No. FAA– 

2013–0204; Directorate Identifier 2012– 

NM–229–AD. 

(a) Comments Due Date 

We must receive comments by April 22, 

2013. 

(b) Affected ADs 

None. 

(c) Applicability 

This AD applies to The Boeing Company 

Model 747–400 and 747–400F series 

airplanes, certificated in any category, line 

numbers 1076 through 1419 inclusive. 

(d) Subject 

Joint Aircraft System Component (JASC)/ 

Air Transport Association (ATA) of America 

Code 53, Fuselage. 

(e) Unsafe Condition 

This AD was prompted by reports of 

cracking in the outboard flange of the 

longeron extension fittings, which attach to 

the wing-to-body fairing support frame. We 

are issuing this AD to detect and correct 

cracks in the longeron extension fittings, 

which can become large and adversely affect 

the structural integrity of the airplane. 

(f) Compliance 

Comply with this AD within the 

compliance times specified, unless already 

done. 

(g) Inspection of Longeron Extension Fitting 

For all airplanes: Except as required by 

paragraphs (i)(1) and (i)(4) of this AD, at the 

time specified in table 1 of paragraph 1.E., 

‘‘Compliance,’’ of Boeing Alert Service 

Bulletin 747–53A2860, dated December 4, 

2012: Do a surface high frequency eddy 

current (HFEC) inspection of the left and 

right longeron extension fittings for cracking, 

and do all applicable corrective actions, in 

accordance with the Accomplishment 

Instructions of Boeing Alert Service Bulletin 

747–53A2860, dated December 4, 2012, 

except as required by paragraphs (i)(2) and 

(i)(3) of this AD. Do all applicable corrective 

actions before further flight. If no cracking is 

found, repeat the inspection thereafter at the 

intervals specified in paragraph 1.E., 

‘‘Compliance,’’ of Boeing Alert Service 

Bulletin 747–53A2860, dated December 4, 

2012, until a permanent repair, longeron 

extension fitting replacement, or preventative 

modification is done, in accordance with the 

Accomplishment Instructions of Boeing Alert 

Service Bulletin 747–53A2860, dated 

December 4, 2012. 

(h) Inspection of Temporary Repair and 

Corrective Actions 

For airplanes on which a temporary repair 

as specified in Boeing Alert Service Bulletin 

747–53A2860 has been done: At the times 

specified in table 2 of paragraph 1.E., 

‘‘Compliance,’’ of Boeing Alert Service 

Bulletin 747–53A2860, dated December 4, 

2012, do a surface HFEC inspection of the 

temporary repair of the longeron extension 

fittings for cracking, and all applicable 

corrective actions, in accordance with the 

Accomplishment Instructions of Boeing Alert 

Service Bulletin 747–53A2860, dated 

December 4, 2012, except as required by 

paragraph (i)(3) of this AD. Do all applicable 

corrective actions before further flight. 

(i) Exceptions to Service Bulletin 

Specifications 

The following exceptions apply to this AD. 

(1) Where Boeing Alert Service Bulletin 

747–53A2860, dated December 4, 2012, 

specifies a compliance time relative to the 

issue date of that service bulletin, this AD 

requires compliance within the specified 

compliance time after the effective date of 

this AD. 

(2) Where Boeing Alert Service Bulletin 

747–53A2860, dated December 4, 2012, 

specifies to contact Boeing for repair 

information: Before further flight, repair 

using a method approved in accordance with 

the procedures specified in paragraph (k) of 

this AD. 

(3) For airplanes not identified in Boeing 

Alert Service Bulletin 747–53A2860, dated 

December 4, 2012: These airplanes are in 

Group 1 for the purposes of this AD and are 

required to do the applicable actions 

specified in the Accomplishment 

Instructions of Boeing Alert Service Bulletin 

747–53A2860, dated December 4, 2012. 

(4) Where Boeing Alert Service Bulletin 

747–53A2860, dated December 4, 2012, 

specifies ‘‘all airplanes,’’ this means all 

airplanes identified in paragraph (c) of this 

AD. 

(j) Optional Terminating Action 

Doing the permanent repair, longeron 

extension fitting replacement, or preventative 

modification, in accordance with the 

Accomplishment Instructions of Boeing Alert 

Service Bulletin 747–53A2860, dated 

December 4, 2012, terminates the repetitive 

inspection required by paragraph (g) of this 

AD. 

(k) Alternative Methods of Compliance 

(AMOCs) 

(1) The Manager, Seattle Aircraft 

Certification Office, FAA, has the authority to 

approve AMOCs for this AD, if requested 

using the procedures found in 14 CFR 39.19. 

In accordance with 14 CFR 39.19, send your 

request to your principal inspector or local 

Flight Standards District Office, as 

appropriate. If sending information directly 

to the manager of the ACO, send it to the 

attention of the person identified in the 

Related Information section of this AD. 

Information may be emailed to: 9-ANMSeattle-ACO-AMOC-Requests@faa.gov. 

(2) Before using any approved AMOC, 

notify your appropriate principal inspector, 

or lacking a principal inspector, the manager 

of the local flight standards district office/ 

certificate holding district office. 

(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 the 

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. 

(l) Related Information 

(1) For more information about this AD, 

contact Nathan Weigand, Aerospace 

Engineer, Airframe Branch, ANM–120S, 

FAA, Seattle Aircraft Certification Office, 

1601 Lind Avenue SW., Renton, Washington 

98057–3356; phone: 425–917–6428; fax: 425– 

917–6590; email: 

Nathan.P.Weigand@faa.gov. 

(2) For Boeing service information 

identified in this AD, contact Boeing 

Commercial Airplanes, Attention: Data & 

Services Management, P.O. Box 3707, MC 

2H–65, Seattle, WA 98124–2207; telephone 

206- 544–5000, extension 1; fax 206–766– 


emcdonald on DSK67QTVN1PROD with PROPOSALS
14734 Federal Register / Vol. 78, No. 45 / Thursday, March 7, 2013 / Proposed Rules 

5680; Internet https:// 

www.myboeingfleet.com. You may also 

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. 

Issued in Renton, Washington, on February 

25, 2013. 

Ali Bahrami, 

Manager, Transport Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. 2013–05189 Filed 3–6–13; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2012–0268; Directorate 

Identifier 2011–NM–129–AD] 

RIN 2120–AA64 

Airworthiness Directives; The Boeing 

Company Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Supplemental notice of 

proposed rulemaking (NPRM); 

reopening of comment period. 

SUMMARY: We are revising an earlier 

proposed airworthiness directive (AD) 

for certain The Boeing Company Model 

737–600, –700, –700C, –800, –900 and 

–900ER series airplanes. That NPRM 

proposed to require inspecting for a 

serial number that starts with the letters 

‘‘SAIC’’ on the left- and right-side 

horizontal stabilizer identification plate; 

a detailed inspection for correct bolt 

protrusion and chamfer of the 

termination fitting bolts of the 

horizontal stabilizer rear spar, if 

necessary; inspecting to determine if 

certain bolts are installed, if necessary; 

and doing related investigative and 

corrective actions if necessary. That 

NPRM was prompted by reports of 

incorrectly installed bolts common to 

the rear spar termination fitting on the 

horizontal stabilizer. This action revises 

that NPRM by adding airplanes to the 

applicability. We are proposing this 

supplemental NPRM to prevent loss of 

structural integrity of the horizontal 

stabilizer attachment and loss of control 

of the airplane. Since these actions 

impose an additional burden over that 

proposed in the NPRM, we are 

reopening the comment period to allow 

the public the chance to comment on 

these proposed changes. 

DATES: We must receive comments on 

this supplemental NPRM by April 22, 

2013. 

ADDRESSES: You may send comments, 

using the procedures found in 14 CFR 

11.43 and 11.45, 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, P.O. Box 3707, 

MC 2H–65, Seattle, Washington 98124– 

2207; telephone 206–544–5000, 

extension 1; fax 206–766–5680; 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. 

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 

(phone: 800–647–5527) is in the 

ADDRESSES section. Comments will be 

available in the AD docket shortly after 

receipt. 

FOR FURTHER INFORMATION CONTACT: 

Nancy Marsh, Aerospace Engineer, 

Airframe Branch, ANM–120S, FAA, 

Seattle Aircraft Certification Office 

(ACO), 1601 Lind Avenue SW., Renton, 

Washington 98057–3356; phone: 425– 

917–6440; fax: 425–917–6590; email: 

nancy.marsh@faa.gov. 

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–2012–0268; Directorate Identifier 

2011–NM–129–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 

We issued an NPRM to amend 14 CFR 

part 39 to include an AD that would 

apply to certain The Boeing Company 

Model 737–600, –700, –700C, –800, and 

–900 series airplanes. That NPRM 

published in the Federal Register on 

March 20, 2012 (77 FR 16188). That 

NPRM proposed to require inspecting 

for a serial number that starts with the 

letters ‘‘SAIC’’ on the left- and right-side 

horizontal stabilizer identification plate; 

a detailed inspection for correct bolt 

protrusion and chamfer of the 

termination fitting bolts of the 

horizontal stabilizer rear spar, if 

necessary; inspecting to determine if 

certain bolts are installed, if necessary; 

and doing related investigative and 

corrective actions if necessary. 

Actions Since Previous NPRM (77 FR 

16188, March 20, 2012) Was Issued 

Since we issued the previous NPRM 

(77 FR 16188, March 20, 2012), we have 

determined that horizontal stabilizers 

are frequently rotated on the fleet and 

could be installed on any Model 737– 

600, –700, –700C, –800, and –900 

airplane, including airplanes outside the 

applicability of the NPRM. Therefore, 

we have determined that the identified 

unsafe condition may exist on all Model 

737–600, –700, –700C, –800, –900, and 

–900ER series airplanes. 

Comments 

We gave the public the opportunity to 

comment on the previous NPRM (77 FR 

16188, March 20, 2012). The following 

presents the comments received on the 

NPRM and the FAA’s response to each 

comment. 

Support for the Previous NPRM (77 FR 

16188, March 20, 2012) 

United Airlines stated it supports the 

previous NPRM (77 FR 16188, March 

20, 2012). 


emcdonald on DSK67QTVN1PROD with PROPOSALS