Federal Register / Vol. 76, No. 162 / Monday, August 22, 2011 / Rules and Regulations 52217 

attachment lugs. We are issuing this AD to 

prevent high-cycle fatigue cracking of the fan 

rotor spinner support attachment lugs, 

leading to separation of the fan rotor spinner 

assembly, uncontained failure of the engine, 

and damage to the airplane. 

Compliance 

(e) Comply with this AD within 1,800 

hours-in-service after the effective date of 

this AD, unless already done. 

Removal of Fan Rotor Blade Retainers 

(f) Remove from service the 24 fan rotor 

blade retainers, P/N 2050M56P02. 

Removal of Fan Rotor Spinner Support 

(g) Remove from service the fan rotor 

spinner support that operated with the fan 

rotor blade retainers removed in paragraph (f) 

of this AD. 

Installation Prohibition 

(h) After the effective date of this AD, do 

not install any fan rotor blade retainer, P/N 

2050M56P02, into any engine. Do not 

attempt to repair, make serviceable, or reinstall, this part. 

(i) After the effective date of this AD, do 

not install any fan rotor spinner support 

removed in paragraph (g) of this AD, into any 

engine. Do not attempt to repair, make 

serviceable, or re-install, this part. 

Alternative Methods of Compliance 

(AMOCs) 

(j) The Manager, Engine Certification 

Office, FAA, has the authority to approve 

AMOCs for this AD, if requested using the 

procedures found in 14 CFR 39.19. 

Related Information 

(k) For more information about this AD, 

contact John Frost, Aerospace Engineer, 

Engine Certification Office, FAA, 12 New 

England Executive Park, Burlington, MA 

01803; phone: 781–238–7756; fax: 781–238– 

7199; e-mail: john.frost@faa.gov. 

(l) Refer to GE Service Bulletin No. CF34– 

10E S/B 72–0186, for related information. 

Contact GE–Aviation, M/D Rm. 285, One 

Neumann Way, Cincinnati, OH 45215, 

phone: 513–552–3272; e-mail: 

geae.aoc@ge.com, for a copy of this service 

information. You may review copies of the 

referenced service information at the FAA, 

Engine & Propeller Directorate, 12 New 

England Executive Park, Burlington, MA. For 

information on the availability of this 

material at the FAA, call 781–238–7125. 

Issued in Burlington, Massachusetts, on 

August 15, 2011. 

Peter A. White, 

Manager, Engine & Propeller Directorate, 

Aircraft Certification Service. 

[FR Doc. 2011–21313 Filed 8–19–11; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2011–0385; Directorate 

Identifier 2010–NM–256–AD; Amendment 

39–16780; AD 2011–17–16] 

RIN 2120–AA64 

Airworthiness Directives; Airbus Model 

A330–200, A330–300, A340–300, A340– 

500, and A340–600 Series Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), Department of 

Transportation (DOT). 

ACTION: Final rule. 

SUMMARY: We are adopting a new 

airworthiness directive (AD) for the 

products listed above. This AD results 

from mandatory continuing 

airworthiness information (MCAI) 

originated by an aviation authority of 

another country to identify and correct 

an unsafe condition on an aviation 

product. The MCAI describes the unsafe 

condition as: 

During a Back-up Control Module (BCM) 

retrofit campaign * * *, some BCMs have 

been found with loose gyrometer screws. 

* * * When the aeroplane is in control 

back up configuration (considered to be an 

extremely remote case), an oscillation of the 

BCM output order may cause degradation of 

the BCM piloting laws, potentially leading to 

erratic motion of the rudder and possible 

subsequent impact on the Dutch Roll, which 

constitutes an unsafe condition. 

* * * * * 

* * * [S]everal Pedal Feel Trim Units 

(PFTU) have been found with loose or broken 

screws during the accomplishment of 

maintenance tasks on A330 fitted with 

electrical rudder and A340–600. The loose or 

failed screws could lead to the loss of the 

coupling between the Rotary Variable 

Differential Transducer (RVDT) shaft and the 

PFTU shaft, and consequently to a potential 

rudder runaway when the BCM is activated. 

* * * * * 

The unsafe condition is loss of control 

of the airplane. We are issuing this AD 

to require actions to correct the unsafe 

condition on these products. 

DATES: This AD becomes effective 

September 26, 2011. 

The Director of the Federal Register 

approved the incorporation by reference 

of certain publications listed in this AD 

as of September 26, 2011. 

ADDRESSES: You may examine the AD 

docket on the Internet at http:// 

www.regulations.gov or in person at the 

U.S. Department of Transportation, 

Docket Operations, M–30, West 

Building Ground Floor, Room W12–140, 

1200 New Jersey Avenue, SE., 

Washington, DC. 

FOR FURTHER INFORMATION CONTACT: 

Vladimir Ulyanov, Aerospace Engineer, 

International Branch, ANM–116, 

Transport Airplane Directorate, FAA, 

1601 Lind Avenue, SW., Renton, 

Washington 98057–3356; telephone 

(425) 227–1138; fax (425) 227–1149. 

SUPPLEMENTARY INFORMATION: 

Discussion 

We issued a notice of proposed 

rulemaking (NPRM) to amend 14 CFR 

part 39 to include an AD that would 

apply to the specified products. That 

NPRM was published in the Federal 

Register on April 26, 2011 (76 FR 

23218). That NPRM proposed to correct 

an unsafe condition for the specified 

products. The MCAI states: 

During a Back-up Control Module (BCM) 

retrofit campaign in accordance with 

[European Aviation Safety Agency] (EASA) 

AD 2006–0313 requirements, some BCMs 

have been found with loose gyrometer 

screws. 

The gyrometer is installed on the DELRIN 

plate by internal screws and the DELRIN 

plate is installed on BCM casing by external 

screws. 

Investigations done by the BCM 

manufacturer SAGEM have shown that the 

root cause of these events is a lack of design 

robustness of the BCM[.] When the aeroplane 

is in control back up configuration 

(considered to be an extremely remote case), 

an oscillation of the BCM output order may 

cause degradation of the BCM piloting laws, 

potentially leading to erratic motion of the 

rudder and possible subsequent impact on 

the Dutch Roll, which constitutes an unsafe 

condition. 

EASA AD 2008–0131 was issued to 

prohibit aeroplane dispatch with FCPC3 

[flight control primary computer] inoperative 

(from GO IF to NO GO) as an interim 

solution, limited to A330 and A340–300 

fitted with electrical rudder. 

After EASA AD 2008–0131 issuance, 

several Pedal Feel Trim Units (PFTU) have 

been found with loose or broken screws 

during the accomplishment of maintenance 

tasks on A330 fitted with electrical rudder 

and A340–600. The loose or failed screws 

could lead to the loss of the coupling 

between the Rotary Variable Differential 

Transducer (RVDT) shaft and the PFTU shaft, 

and consequently to a potential rudder 

runaway when the BCM is activated. 

EASA AD 2009–0153 retained the 

requirements of EASA AD 2008–0131 and 

extended the applicability to A340–500/600 

aeroplanes. 

This [EASA] AD, which supersedes EASA 

AD 2009–0153 retaining its requirements, 

requires the installation of: 

—a new BCM on A330 and A340–200/–300 

series aeroplanes fitted with electrical 

rudder, and 

—an improved PFTU on A330 and A340– 

200/–300 series aeroplanes fitted with an 

electrical rudder and A340–500/&600 

series aeroplanes, 

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52218 Federal Register / Vol. 76, No. 162 / Monday, August 22, 2011 / Rules and Regulations 

which, once installed, eliminate the root 

cause of the unsafe condition and cancel the 

operational limitation. 

* * * * * 

The unsafe condition is loss of control 

of the airplane. You may obtain further 

information by examining the MCAI in 

the AD docket. 

Comments 

We gave the public the opportunity to 

participate in developing this AD. We 

received no comments on the NPRM or 

on the determination of the cost to the 

public. 

Conclusion 

We reviewed the available data and 

determined that air safety and the 

public interest require adopting the AD 

as proposed. 

Differences Between This AD and the 

MCAI or Service Information 

We have reviewed the MCAI and 

related service information and, in 

general, agree with their substance. But 

we might have found it necessary to use 

different words from those in the MCAI 

to ensure the AD is clear for U.S. 

operators and is enforceable. In making 

these changes, we do not intend to differ 

substantively from the information 

provided in the MCAI and related 

service information. 

We might also have required different 

actions in this AD from those in the 

MCAI in order to follow our FAA 

policies. Any such differences are 

highlighted in a Note within the AD. 

Costs of Compliance 

We estimate that this AD will affect 

46 products of U.S. registry. We also 

estimate that it will take about 17 workhours per product to comply with the 

basic requirements of this AD. The 

average labor rate is $85 per work-hour. 

Required parts will cost about $0 per 

product. Where the service information 

lists required parts costs that are 

covered under warranty, we have 

assumed that there will be no charge for 

these parts. As we do not control 

warranty coverage for affected parties, 

some parties may incur costs higher 

than estimated here. Based on these 

figures, we estimate the cost of this AD 

to the U.S. operators to be $66,470, or 

$1,445 per product. 

Authority for This Rulemaking 

Title 49 of the United States Code 

specifies the FAA’s authority to issue 

rules on aviation safety. Subtitle I, 

section 106, describes the authority of 

the FAA Administrator. ‘‘Subtitle VII: 

Aviation Programs,’’ describes in more 

detail the scope of the Agency’s 

authority. 

We are issuing this rulemaking under 

the authority described in ‘‘Subtitle VII, 

Part A, Subpart III, Section 44701: 

General requirements.’’ Under that 

section, Congress charges the FAA with 

promoting safe flight of civil aircraft in 

air commerce by prescribing regulations 

for practices, methods, and procedures 

the Administrator finds necessary for 

safety in air commerce. This regulation 

is within the scope of that authority 

because it addresses an unsafe condition 

that is likely to exist or develop on 

products identified in this rulemaking 

action. 

Regulatory Findings 

We determined that this 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 this AD: 

1. Is not a ’’significant regulatory 

action’’ under Executive Order 12866; 

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

DOT Regulatory Policies and Procedures 

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

3. Will not have a significant 

economic impact, positive or negative, 

on a substantial number of small entities 

under the criteria of the Regulatory 

Flexibility Act. 

We prepared a regulatory evaluation 

of the estimated costs to comply with 

this AD and placed it in the AD docket. 

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 the NPRM, 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. 

List of Subjects in 14 CFR Part 39 

Air transportation, Aircraft, Aviation 

safety, Incorporation by reference, 

Safety. 

Adoption of the Amendment 

Accordingly, under the authority 

delegated to me by the Administrator, 

the FAA amends 14 CFR part 39 as 

follows: 

PART 39—AIRWORTHINESS 

DIRECTIVES 

■ 1. The authority citation for part 39 

continues to read as follows: 

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

§ 39.13 [Amended] 

■ 2. The FAA amends § 39.13 by adding 

the following new AD: 

2011–17–16 Airbus: Amendment 39–16780. 

Docket No. FAA–2011–0385; Directorate 

Identifier 2010–NM–256–AD. 

Effective Date 

(a) This airworthiness directive (AD) 

becomes effective September 26, 2011. 

Affected ADs 

(b) None. 

Applicability 

(c) This AD applies to airplanes specified 

in paragraphs (c)(1), (c)(2), and (c)(3) of this 

AD, certificated in any category. 

(1) Airbus Model A330–201, –202, –203, 

–223, –223F, –243, –243F, –301, -302, –303, 

–321, –322, –323, –341, –342, and –343 

airplanes, all manufacturer serial numbers on 

which Airbus modification 49144 (install 

electrical rudder) has been embodied in 

production, except those on which Airbus 

modification 58118 and Airbus modification 

200667 have been embodied in production. 

(2) Airbus Model A340–311, –312, and 

–313 airplanes, all manufacturer serial 

numbers on which Airbus modification 

49144 has been embodied in production, 

except those on which Airbus modification 

58118 and Airbus modification 200667 have 

been embodied in production. 

(3) Airbus Model A340–541 and –642 

airplanes, all manufacturer serial numbers, 

except those on which Airbus modification 

200667 has been embodied in production. 

Subject 

(d) Air Transport Association (ATA) of 

America Code 27: Flight Controls. 

Reason 

(e) The mandatory continuing 

airworthiness information (MCAI) states: 

During a Back-up Control Module (BCM) 

retrofit campaign * * *, some BCMs have 

been found with loose gyrometer screws. 

* * * When the aeroplane is in control 

back up configuration (considered to be an 

extremely remote case), an oscillation of the 

BCM output order may cause degradation of 

the BCM piloting laws, potentially leading to 

erratic motion of the rudder and possible 

subsequent impact on the Dutch Roll, which 

constitutes an unsafe condition. 

* * * * * 

* * * [S]everal Pedal Feel Trim Units 

(PFTU) have been found with loose or broken 

screws during the accomplishment of 

maintenance tasks on A330 fitted with 

electrical rudder and A340–600. The loose or 

failed screws could lead to the loss of the 

coupling between the Rotary Variable 

Differential Transducer (RVDT) shaft and the 

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Federal Register / Vol. 76, No. 162 / Monday, August 22, 2011 / Rules and Regulations 52219 

PFTU shaft, and consequently to a potential 

rudder runaway when the BCM is activated. 

* * * * * 

The unsafe condition is loss of control 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. 

Dispatch Prohibition 

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

dispatch with the flight control primary 

computer (FCPC) 3 ‘‘PRIM 3’’ inoperative is 

prohibited unless the applicable 

modifications required by this AD have been 

done within the compliance time in this AD. 

Airplane Flight Manual (AFM) Revision 

(h) Within 30 days after the effective date 

of this AD, revise the Limitations section of 

the Airbus A330 or A340 AFM, as applicable, 

to include the following statement:’’Dispatch 

with the flight control primary computer 

(FCPC) 3 ‘‘PRIM 3’’ inoperative is 

prohibited.’’ This may be done by inserting 

a copy of this AD into the applicable AFM. 

Note 1: When a statement identical to that 

in paragraph (h) of this AD has been included 

in the general revisions of the applicable 

AFM, the general revisions may be inserted 

into the applicable AFM, and the copy of this 

AD may be removed from the applicable 

AFM. 

Modification 

(i) For Airbus Model A330–201, –202, 

–203, –223, –223F, –243, –243F, –301, –302, 

–303, –321, –322, –323, –341, –342, –343, 

and A340–311, –312, and –313 series 

airplanes: Within 48 months after the 

effective date of this AD, do the actions 

specified in paragraphs (i)(1) and (i)(2) of this 

AD: 

(1) Modify the BCM, in accordance with 

the Accomplishment Instruction of Airbus 

Service Bulletin A330–27–3161 (for Model 

A330–201, –202, –203, –223, –223F, –243, 

–243F, –301, –302, –303, –321, –322, –341, 

–343 airplanes) or A340–27–4160 (for Model 

A340–311, –312, and –313 airplanes), both 

dated November 6, 2009. 

(2) Modify the PFTU, in accordance with 

the Accomplishment Instructions of Airbus 

Mandatory Service Bulletin A330–27–3169 

or A340–27–4167, both dated May 3, 2010, 

as applicable. 

(j) For Airbus Model 340–541 and –642 

airplanes: Within 48 months after the 

effective date of this AD, modify the PFTU, 

in accordance with the Accomplishment 

Instructions of Airbus Mandatory Service 

Bulletin A340–27–5053, dated May 3, 2010. 

Terminating Action 

(k) Modifying both the BCM and PFTU as 

required by paragraphs (i)(1) and (i)(2) of this 

AD terminates the requirements of 

paragraphs (g) and (h) of this AD. 

(l) Modifying the PFTU as required by 

paragraph (j) of this AD terminates the 

requirements in paragraphs (g) and (h) of this 

AD. 

FAA AD Differences 

Note 2: This AD differs from the MCAI 

and/or service information as follows: No 

differences. 

Other FAA AD Provisions 

(m) The following provisions also apply to 

this AD: 

(1) Alternative Methods of Compliance 

(AMOCs): The Manager, International 

Branch, ANM–116, Transport Airplane 

Directorate, FAA, has the authority to 

approve AMOCs for this AD, if requested 

using the procedures found in 14 CFR 39.19. 

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 International Branch, send it to ATTN: 

Vladimir Ulyanov, Aerospace Engineer, 

International Branch, ANM–116, Transport 

Airplane Directorate, FAA, 1601 Lind 

Avenue, SW., Renton, Washington 98057– 

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

227–1149. Information may be e-mailed to: 

9–ANM–116–AMOC–REQUESTS@faa.gov. 

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. The AMOC 

approval letter must specifically reference 

this AD. 

(2) Airworthy Product: For any requirement 

in this AD to obtain corrective actions from 

a manufacturer or other source, use these 

actions if they are FAA-approved. Corrective 

actions are considered FAA-approved if they 

are approved by the State of Design Authority 

(or their delegated agent). You are required 

to assure the product is airworthy before it 

is returned to service. 

Related Information 

(n) Refer to MCAI European Aviation 

Safety Agency Airworthiness Directive 2010– 

0191, dated September 27, 2010 [Corrected 

October 7, 2010], and the service bulletins 

listed in table 1 of this AD, for related 

information. 

TABLE 1—AIRBUS SERVICE BULLETINS

Document Date 

Airbus Mandatory Service Bulletin A330–27–3169 ..................................................................................................................... May 3, 2010. 

Airbus Mandatory Service Bulletin A340–27–4167 ..................................................................................................................... May 3, 2010. 

Airbus Mandatory Service Bulletin A340–27–5053 ..................................................................................................................... May 3, 2010. 

Airbus Service Bulletin A330–27–3161 ....................................................................................................................................... November 6, 2009. 

Airbus Service Bulletin A340–27–4160 ....................................................................................................................................... November 6, 2009. 

Material Incorporated by Reference 

(o) You must use the service information 

contained in table 2 of this AD, as applicable, 

to do the actions required by this AD, unless 

the AD specifies otherwise. 

(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 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; e-mail 

airworthiness.A330–A340@airbus.com; 

Internet http://www.airbus.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. 

TABLE 2—MATERIAL INCORPORATED BY REFERENCE

Document Date 

Airbus Mandatory Service Bulletin A330–27–3169 ..................................................................................................................... May 3, 2010. 

Airbus Mandatory Service Bulletin A340–27–4167 ..................................................................................................................... May 3, 2010. 

Airbus Mandatory Service Bulletin A340–27–5053 ..................................................................................................................... May 3, 2010. 

Airbus Service Bulletin A330–27–3161 ....................................................................................................................................... November 6, 2009. 

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52220 Federal Register / Vol. 76, No. 162 / Monday, August 22, 2011 / Rules and Regulations 

TABLE 2—MATERIAL INCORPORATED BY REFERENCE—Continued 

Document Date 

Airbus Service Bulletin A340–27–4160 ....................................................................................................................................... November 6, 2009. 

Issued in Renton, Washington on August 

10, 2011. 

Ali Bahrami, 

Manager, Transport Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. 2011–21152 Filed 8–19–11; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2011–0088 Directorate 

Identifier 2010–CE–072–AD; Amendment 

39–16779; AD 2011–17–15] 

RIN 2120–AA64 

Airworthiness Directives; Embraer— 

Empresa Brasileira de Aeronautica 

S.A. (EMBRAER) Model EMB–500 

Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), Department of 

Transportation (DOT). 

ACTION: Final Rule. 

SUMMARY: We are adopting a new 

airworthiness directive (AD) for the 

products listed above. This AD results 

from mandatory continuing 

airworthiness information (MCAI) 

issued by an aviation authority of 

another country to identify and correct 

an unsafe condition on an aviation 

product. The MCAI describes the unsafe 

condition as: 

It has been found that moisture may 

accumulate and freeze, under certain 

conditions, in the gap between the AOA vane 

base assembly and the stationary ring of the 

sensor’s body. If freezing occurs both AOA 

sensors may get stuck and the Stall Warning 

Protection System (SWPS) will be no longer 

effective without alerting. This may result in 

inadvertent aerodynamic stall and loss of 

controllability of the airplane. 

We are issuing this AD to require 

actions to correct the unsafe condition 

on these products. 

DATES: This AD becomes effective 

September 26, 2011. 

On September 26, 2011, the Director 

of the Federal Register approved the 

incorporation by reference of certain 

publications listed in this AD. 

ADDRESSES: You may examine the AD 

docket on the Internet at http:// 

www.regulations.gov or in person at 

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 service information identified in 

this AD, contact EMBRAER Empresa 

Brasileira de Aerona ́utica S.A., Phenom 

Maintenance Support, Av. Brig. Farina 

Lima, 2170, Sao Jose dos Campos—SP, 

CEP: 12227–901—PO Box: 36/2, 

BRASIL; telephone: ++55 12 3927–5383; 

fax: ++55 12 3927–2619; e-mail: 

phenom.reliability@ embraer.com.br; 

Internet: http://www.embraer.com.br. 

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. 

FOR FURTHER INFORMATION CONTACT: Jim 

Rutherford, Aerospace Engineer, FAA, 

Small Airplane Directorate, 901 Locust, 

Room 301, Kansas City, Missouri 64106; 

telephone: (816) 329–4165; fax: (816) 

329–4090; e-mail: 

jim.rutherford@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Discussion 

We issued a notice of proposed 

rulemaking (NPRM) to amend 14 CFR 

part 39 to include an AD that would 

apply to the specified products. That 

NPRM was published in the Federal 

Register on May 10, 2011 (76 FR 26959). 

That NPRM proposed to correct an 

unsafe condition for the specified 

products. The MCAI states: 

It has been found that moisture may 

accumulate and freeze, under certain 

conditions, in the gap between the AOA vane 

base assembly and the stationary ring of the 

sensor’s body. If freezing occurs both AOA 

sensors may get stuck and the Stall Warning 

Protection System (SWPS) will be no longer 

effective without alerting. This may result in 

inadvertent aerodynamic stall and loss of 

controllability of the airplane. 

Since this condition may occur in other 

airplanes of the same type and affects flight 

safety, a corrective action is required. Thus, 

sufficient reason exists to request compliance 

with this AD in the indicated time limit. 

Comments 

We gave the public the opportunity to 

participate in developing this AD. We 

received no comments on the NPRM or 

on the determination of the cost to the 

public. 

Conclusion 

We reviewed the available data and 

determined that air safety and the 

public interest require adopting the AD 

as proposed. 

Differences Between This AD and the 

MCAI or Service Information 

We have reviewed the MCAI and 

related service information and, in 

general, agree with their substance. But 

we might have found it necessary to use 

different words from those in the MCAI 

to ensure the AD is clear for U.S. 

operators and is enforceable. In making 

these changes, we do not intend to differ 

substantively from the information 

provided in the MCAI and related 

service information. 

We might also have required different 

actions in this AD from those in the 

MCAI in order to follow FAA policies. 

Any such differences are highlighted in 

a NOTE within the AD. 

Costs of Compliance 

We estimate that this AD will affect 

101 products of U.S. registry. 

We estimate that 85 products of U.S. 

registry will require the modification 

and that it will take about 9.5 workhours per product to comply with the 

modification requirements of this AD. 

The average labor rate is $85 per workhour. Required parts will cost about 

$1,550 per product. 

Based on these figures, we estimate 

the cost of the modification requirement 

of this AD on U.S. operators to be 

$200,387.50, or $2,357.50 per product. 

We estimate that 101 products of U.S. 

registry will require an inspection for 

sealant application. We estimate it will 

take .5 hour to comply with the 

inspection requirements of this AD. 

Based on these figures, we estimate 

the cost of the inspection for the sealant 

application requirement of this AD on 

U.S. operators to be $4,292.50, or $42.50 

per product. 

In addition, we estimate that any 

necessary follow-on actions will take 

about 1.5 work-hours and require parts 

costing $50, for a cost of $177.50 per 

product. We have no way of 

determining the number of products 

that may need these actions. 

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