46540 Federal Register / Vol. 78, No. 148 / Thursday, August 1, 2013 / Proposed Rules 

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– 

2013–0666; Directorate Identifier 2013– 

NM–060–AD. 

(a) Comments Due Date 

We must receive comments by September 

16, 2013. 

(b) Affected ADs 

None. 

(c) Applicability 

This AD applies to all The Boeing 

Company Model 727, 727C, 727–100, 727 

–100C, 727–200, and 727–200F series 

airplanes; certificated in any category. 

(d) Subject 

Joint Aircraft System Component (JASC)/ 

Air Transport Association (ATA) of America 

Code 28, Fuel. 

(e) Unsafe Condition 

This AD was prompted by reports 

indicating that a standard fuel tank access 

door was located where an impact-resistant 

access door was required, and stencils were 

missing from some impact-resistant access 

doors. We are issuing this AD to prevent 

foreign object penetration of the fuel tank, 

which could cause a fuel leak near an 

ignition source (e.g., hot brakes), 

consequently leading to a fuel-fed fire. 

(f) Compliance 

Comply with this AD within the 

compliance times specified, unless already 

done. 

(g) Inspections 

Within 72 months after the effective date 

of this AD, do the actions specified in 

paragraphs (g)(1) and (g)(2) of this AD, in 

accordance with the Accomplishment 

Instructions of Boeing Service Bulletin 727– 

28–0134, dated January 12, 2012. 

(1) Do either a general visual inspection or 

ultrasonic non-destructive test of the left- and 

right-hand wing fuel tank access doors to 

determine whether impact-resistant access 

doors are installed in the correct locations. If 

any standard access door is found, before 

further flight, replace with an impactresistant access door, in accordance with the 

Accomplishment Instructions of Boeing 

Service Bulletin 727–28–0134, dated January 

12, 2012. 

(2) Do a general visual inspection of the 

left- and right-hand wing fuel tank impactresistant access doors to verify stencils and 

index markers are applied. If a stencil or 

index marker is missing, before further flight, 

apply stencil or index marker, as applicable, 

in accordance with the Accomplishment 

Instructions of Boeing Service Bulletin 727– 

28–0134, dated January 12, 2012. 

(h) Maintenance Program Revision 

Within 60 days after the effective date of 

this AD, revise the maintenance program to 

incorporate Critical Design Configuration 

Control Limitation (CDCCL) Task 57–AWL– 

01, ‘‘Impact-Resistant Fuel Tank Access 

Door,’’ of Section 1, Airworthiness 

Limitations (AWLs) of Boeing 727–100/200 

Airworthiness Limitations (AWLs) Document 

D6–8766–AWL, Revision September 2012. 

(i) No Alternative CDCCLs 

After accomplishing the revision required 

by paragraph (h) of this AD, no alternative 

CDCCLs may be used unless the CDCCLs are 

approved as an alternative method of 

compliance in accordance with the 

procedures specified in paragraph (j) of this 

AD. 

(j) Alternative Methods of Compliance 

(AMOCs) 

(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. 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. 

(k) Related Information 

(1) For more information about this AD, 

contact Suzanne Lucier, Aerospace Engineer, 

Propulsion Branch, ANM–140S, FAA, Seattle 

Aircraft Certification Office, 1601 Lind 

Avenue SW., Renton, WA 98057–3356; 

phone: 425–917–6438; fax: 425–917–6590; 

email: suzanne.lucier@faa.gov. 

(2) For 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 206–766–5680; 

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, 

WA. For information on the availability of 

this material at the FAA, call 425–227–1221. 

Issued in Renton, Washington, on July 21, 

2013. 

Stephen P. Boyd, 

Acting Manager, Transport Airplane 

Directorate, Aircraft Certification Service. 

[FR Doc. 2013–18507 Filed 7–31–13; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2013–0667; Directorate 

Identifier 2013–NM–062–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 

airplanes. This proposed AD was 

prompted by reports of fasteners 

missing on an airplane undergoing a 

passenger-to-freighter conversion. This 

proposed AD would require doing a 

general visual inspection of the station 

1920 splice clip for correct fastener 

installation, and related investigative 

and corrective actions if necessary. We 

are proposing this AD to detect and 

correct missing or incorrect fasteners, 

which can lead to cracking and loss of 

load carrying capacity, resulting in a 

possible decompression event. 

DATES: We must receive comments on 

this proposed AD by September 16, 

2013. 

ADDRESSES: You may send comments, 

using the procedures found in 14 CFR 

11.43 and 11.45, by any of the following 

methods: 


emcdonald on DSK67QTVN1PROD with PROPOSALS
Federal Register / Vol. 78, No. 148 / Thursday, August 1, 2013 / Proposed Rules 46541 

• 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 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, WA. 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: Bill 

Ashforth, Aerospace Engineer, Airframe 

Branch, ANM–120S, FAA, Seattle 

Aircraft Certification Office, 1601 Lind 

Avenue SW., Renton, WA 98057–3356; 

phone: 425–917–6432; fax: 425–917– 

6590; email: bill.ashforth@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– 

2013–0667; Directorate Identifier 2013– 

NM–062–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 have received a report of an 

airplane, while undergoing a passengerto-freighter conversion, missing 

fasteners on the station 1920 splice clip. 

The possibility of this discrepancy 

exists on airplanes already delivered. 

This condition, if not corrected, could 

result in cracking and loss of load 

carrying capacity, resulting in a possible 

decompression event. 

Relevant Service Information 

We reviewed Boeing Alert Service 

Bulletin 747–53A2844, Revision 1, 

dated July 30, 2012. For information on 

the procedures and compliance times, 

see this service information at http:// 

www.regulations.gov by searching for 

Docket No. FAA–2013–0667. 

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 actions, and (2) 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 

Although the service bulletin 

specifies that operators may contact the 

manufacturer for disposition of certain 

repair conditions, this proposed AD 

would require operators to repair those 

conditions in accordance with a method 

approved by the FAA. 

Costs of Compliance 

We estimate that this proposed AD 

affects 3 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 

Inspection for correct fastener installation ............ 2 work-hours × $85 per hour = $170 ................... $0 $170 $510 

We estimate the following costs to do 

any necessary repairs 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 these repairs: 

ON-CONDITION COSTS

Action Labor cost Parts cost Cost per 

product 

Inspections for cracking .................................................... 3 work-hours × $85 per hour = $255 ............................... $0 $255 

Fastener installation .......................................................... 2 work-hours × $85 per hour = $170 ............................... 0 170 

Repair ................................................................................ 2 work-hours × $85 per hour = $170 ............................... 0 170 


emcdonald on DSK67QTVN1PROD with PROPOSALS
46542 Federal Register / Vol. 78, No. 148 / Thursday, August 1, 2013 / Proposed Rules 

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 

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– 

2013–0667; Directorate Identifier 2013– 

NM–062–AD. 

(a) Comments Due Date 

We must receive comments by September 

16, 2013. 

(b) Affected ADs 

None. 

(c) Applicability 

This AD applies to The Boeing Company 

Model 747–400 series airplanes, certificated 

in any category, as identified in Boeing Alert 

Service Bulletin 747–53A2844, Revision 1, 

dated July 30, 2012. 

(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 

fasteners missing on an airplane undergoing 

a passenger-to-freighter conversion. We are 

issuing this AD to detect and correct missing 

or incorrect fasteners, which can lead to 

cracking and loss of load carrying capacity, 

resulting in a possible decompression event. 

(f) Compliance 

Comply with this AD within the 

compliance times specified, unless already 

done. 

(g) Inspection 

Except as required by paragraph (h)(1) of 

this AD, at the times specified in paragraph 

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

Bulletin 747–53A2844, Revision 1, dated July 

30, 2012: Do a general visual inspection for 

correct installation of the station 1920 splice 

clip common to the auxiliary sill web and the 

tie clip, and do all applicable related 

investigative and corrective actions in 

accordance with the Accomplishment 

Instructions of Boeing Alert Service Bulletin 

747–53A2844, Revision 1, dated July 30, 

2012, except as required by paragraph (h)(2) 

of this AD. Do all applicable related 

investigative and corrective actions before 

further flight. 

(h) Exceptions to the Service Information 

(1) Where Boeing Alert Service Bulletin 

747–53A2844, Revision 1, dated July 30, 

2012, specifies a compliance time ‘‘after the 

original issue date of the service bulletin,’’ 

this AD requires compliance within the 

specified compliance time after the effective 

date of this AD. 

(2) If any cracking is found during any 

inspection required by this AD, and Boeing 

Alert Service Bulletin 747–53A2844, 

Revision 1, dated July 30, 2012, specifies 

contacting Boeing for appropriate action: 

Before further flight, repair using a method 

approved in accordance with the procedures 

specified in paragraph (j) of this AD. 

(i) Credit for Previous Actions 

This paragraph provides credit for actions 

required by paragraph (g) of this AD, if those 

actions were performed before the effective 

date of this AD using Boeing Alert Service 

Bulletin 747–53A2844, dated September 15, 

2011, except the detailed inspection for 

cracking of the auxiliary sill outer chord tee 

and attached parts and all applicable related 

investigative and corrective actions must be 

done in accordance with Boeing Alert 

Service Bulletin 747–53A2844, Revision 1, 

dated July 30, 2012, at the times specified in 

paragraph (g) of this AD. Boeing Alert Service 

Bulletin 747–53A2844, dated September 15, 

2011, is not incorporated by reference in this 

AD. 

(j) Alternative Methods of Compliance 

(AMOCs) 

(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. 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. 

(k) Related Information 

(1) For more information about this AD, 

contact Bill Ashforth, Aerospace Engineer, 

Airframe Branch, ANM–120S, FAA, Seattle 

Aircraft Certification Office, 1601 Lind 

Avenue SW., Renton, WA 98057–3356; 

phone: 425–917–6432; fax: 425–917–6590; 

email: bill.ashforth@faa.gov. 

(2) For 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 206–766–5680; 

Internet https://www.myboeingfleet.com. You 

may review copies of the referenced service 

information at the FAA, Transport Airplane 


emcdonald on DSK67QTVN1PROD with PROPOSALS
Federal Register / Vol. 78, No. 148 / Thursday, August 1, 2013 / Proposed Rules 46543 

Directorate, 1601 Lind Avenue SW., Renton, 

WA. For information on the availability of 

this material at the FAA, call 425–227–1221. 

Issued in Renton, Washington, on July 21, 

2013. 

Stephen P. Boyd, 

Acting Manager, Transport Airplane 

Directorate, Aircraft Certification Service. 

[FR Doc. 2013–18564 Filed 7–31–13; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2013–0665; Directorate 

Identifier 2012–NM–082–AD] 

RIN 2120–AA64 

Airworthiness Directives; Airbus 

Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Notice of proposed rulemaking 

(NPRM). 

SUMMARY: We propose to adopt a new 

airworthiness directive (AD) for all 

Airbus Model A330–300 series airplanes 

and Model A340–200 and –300 series 

airplanes. This proposed AD was 

prompted by reports of corrosion found 

on certain trimmable horizontal 

stabilizer actuators (THSA), affecting the 

ballscrew lower splines between the tie 

bar and the screw-jack. This proposed 

AD would require repetitive detailed 

inspections for corrosion of certain 

THSAs, ballscrew integrity tests if 

necessary; and replacing any affected 

THSA with a serviceable or new and 

improved THSA, if necessary. We are 

proposing this AD to detect and correct 

corrosion of the THSAs, which could 

lead, in the case of ballscrew rupture, to 

the loss of transmission of THSA torque 

loads from the ballscrew to the tie-bar, 

prompting THSA blowback, and 

possibly resulting in loss of control of 

the airplane. 

DATES: We must receive comments on 

this proposed AD by September 16, 

2013. 

ADDRESSES: You may send comments by 

any of the following methods: 

• Federal eRulemaking Portal: Go to 

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

instructions for submitting comments. 

• Fax: (202) 493–2251. 

• Mail: U.S. Department of 

Transportation, Docket Operations, M– 

30, West Building Ground Floor, Room 

W12–140, 1200 New Jersey Avenue SE., 

Washington, DC 20590. 

• Hand Delivery: U.S. Department of 

Transportation, Docket Operations, M– 

30, West Building Ground Floor, Room 

W12–140, 1200 New Jersey Avenue SE., 

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

p.m., Monday through Friday, except 

Federal holidays. 

For Airbus service information 

identified in this proposed AD, contact 

Airbus SAS—Airworthiness Office— 

EAL, 1 Rond Point Maurice Bellonte, 

31707 Blagnac Cedex, France; telephone 

+33 5 61 93 36 96; fax +33 5 61 93 45 

80; email airworthiness.A330- 

A340@airbus.com; Internet http:// 

www.airbus.com. For Goodrich service 

information identified in this proposed 

AD, contact Goodrich Corporation, 

Actuation Systems, Product Support 

Department 13, Avenue de 

L’Eguillette—Saint-Ouen L’Aumone 

Boite Postale 7186 95056, Cergy 

Pontoise Cedex, France; fax: 33–1– 

34326310. You may review copies of the 

referenced service information at the 

FAA, Transport Airplane Directorate, 

1601 Lind Avenue SW., Renton, WA. 

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 Operations office between 9 a.m. 

and 5 p.m., Monday through Friday, 

except Federal holidays. The AD docket 

contains this proposed AD, the 

regulatory evaluation, any comments 

received, and other information. The 

street address for the Docket Operations 

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

the ADDRESSES section. Comments will 

be available in the AD docket shortly 

after receipt. 

FOR FURTHER INFORMATION CONTACT: 

Vladimir Ulyanov, Aerospace Engineer, 

International Branch, ANM–116, 

Transport Airplane Directorate, FAA, 

1601 Lind Avenue SW., Renton, WA 

98057–3356; telephone (425) 227–1138; 

fax (425) 227–1149. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

We invite you to send any written 

relevant data, views, or arguments about 

this proposed AD. Send your comments 

to an address listed under the 

ADDRESSES section. Include ‘‘Docket No. 

FAA–2013–0665; Directorate Identifier 

2012–NM–082–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 based on those comments. 

We will post all comments we 

receive, without change, to http:// 

www.regulations.gov, including any 

personal information you provide. We 

will also post a report summarizing each 

substantive verbal contact we receive 

about this proposed AD. 

Discussion 

The European Aviation Safety Agency 

(EASA), which is the Technical Agent 

for the Member States of the European 

Community, has issued EASA 

Airworthiness Directive 2012–0061R1, 

dated November 30, 2012 (referred to 

after this as ‘‘the MCAI’’), to correct an 

unsafe condition for the specified 

products. The MCAI states: 

Some Trimmable Horizontal Stabilizer 

Actuators (THSA), Part Number (P/N) 47147– 

500, have been found with corrosion, 

affecting the ballscrew lower splines between 

the tie bar and the screw-jack. 

The results of the technical investigations 

have identified that the corrosion was caused 

by a combination of: 

—Contact/friction between the tie bar and the 

inner surface of the ballscrew leading to 

the removal of Molykote (corrosion 

protection) at the level of the tie bar 

splines, 

—Humidity ingress initiating surface 

oxidation starting from areas where 

Molykote is removed, and 

—Water retention in THSA lower part 

leading to corrosion spread out and to the 

creation of a brown deposit (iron oxide). 

The results of the technical investigations 

have also concluded that THSA P/N 47147– 

500 and P/N 47147–700 ballscrews might be 

affected by this corrosion issue. 

THSA P/N 47147–400 ballscrews might be 

affected as well, but should no longer be in 

service, and modified into P/N 47147–500, as 

required by EASA AD 2010–0192 and EASA 

AD 2010–0193 [and as required by FAA AD 

2005–07–04, Amendment 39–14028 (70 FR 

16104, March 30, 2005)]. 

This condition, if not detected and 

corrected, may lead, in case of ballscrew 

rupture, to loss of transmission of THSA 

torque loads from the ballscrew to the tie-bar, 

prompting THSA blowback, possibly 

resulting in loss of control of the aeroplane. 

To correct this potential unsafe condition, 

EASA issued AD 2012–0061 to require 

repetitive [detailed] visual inspections of the 

ballscrew lower splines of THSA having 

P/N 47147–500 or P/N 47147–700 to detect 

corrosion and, depending on findings 

[ballscrew integrity tests], the 

accomplishment of applicable corrective 

actions [replacing the affected THSA with a 

serviceable or improved THSA]. 

Since that [EASA] AD [2012–0061] was 

issued, Airbus published new Service 

Bulletin (SB) A330–27–3194 or Airbus SB 

A340–27–4187 (Airbus modification 202802), 

which allow installation in service of an 

improved THSA P/N 47172–530. 

For the reasons described above, this 

[EASA] AD [2012–0061R1] is revised to 

specify that installation of THSA P/N 47172– 


emcdonald on DSK67QTVN1PROD with PROPOSALS