This section of the FEDERAL REGISTER

contains regulatory documents having general

applicability and legal effect, most of which

are keyed to and codified in the Code of

Federal Regulations, which is published under

50 titles pursuant to 44 U.S.C. 1510.

The Code of Federal Regulations is sold by

the Superintendent of Documents. Prices of

new books are listed in the first FEDERAL

REGISTER issue of each week.

Rules and Regulations Federal Register

9495 

Vol. 76, No. 34 

Friday, February 18, 2011 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 1 

[Docket No. FAA–2010–0812; Amdt. No. 

1–66] 

RIN 2120–AJ81 

Feathering Propeller Systems for 

Light-Sport Aircraft Powered Gliders 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final rule; notice of 

confirmation of effective date. 

SUMMARY: This action confirms the 

effective date of the final rule published 

on January 3, 2011. The final rule 

amends the definition of light-sport 

aircraft by removing ‘‘auto’’ from the 

term ‘‘autofeathering’’ as it applies to 

powered gliders. This amendment will 

allow both manual and autofeathering 

propeller operation for powered gliders 

that qualify as light-sport aircraft. 

DATES: The effective date for the final 

rule published January 3, 2011, at 76 FR 

5, is confirmed as March 4, 2011. 

ADDRESSES: For information on where to 

obtain copies of rulemaking documents 

and other information related to this 

action, see ‘‘How to Obtain Additional 

Information’’ in the SUPPLEMENTARY

INFORMATION section of this document. 

FOR FURTHER INFORMATION CONTACT: For 

technical questions concerning this 

action, contact Terry Chasteen, Federal 

Aviation Administration, Aircraft 

Certification Service, Small Airplane 

Directorate, ACE–114, 901 Locust, Room 

301, Kansas City, MO 64106; telephone: 

(816) 329–4147; fax: (816) 329–4090; 

e-mail: terry.chasteen@faa.gov. For legal 

questions concerning this action, 

contact Paul Greer, Office of Chief 

Counsel, AGC–210, Federal Aviation 

Administration, 800 Independence 

Avenue, SW., Washington, DC 20591; 

telephone: (202) 267–7930; fax: (202) 

267–7971; e-mail: paul.g.greer@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Background 

Before publication of this final rule on 

January 3, 2011 (76 FR 5), Title 14, Code 

of Federal Regulations (14 CFR) 

specified that powered gliders that were 

light-sport aircraft (LSA) had a fixed or 

autofeathering propeller system. The 

restriction to ‘‘autofeathering’’ had 

resulted in confusion to LSA designers. 

The FAA has determined that a 

propeller on an LSA powered glider can 

be safely feathered using either a 

manual or automatic feathering 

propeller system, which justifies 

replacing the term ‘‘autofeathering’’ with 

‘‘feathering.’’ 

Discussion of the Comments 

The FAA received comments from 

eight individual commenters. All 

commenters supported the rule change. 

The commenters generally stated that 

the rule change removes an unnecessary 

restriction to the definition of a lightsport aircraft with no adverse safety 

effect. 

Conclusion 

After consideration of the comments 

submitted in response to the final rule, 

the FAA has determined that no further 

rulemaking action is necessary. 

Therefore, Amendment 1–66 remains in 

effect. 

How To Obtain Additional Information 

A. Rulemaking Documents 

An electronic copy of a rulemaking 

document my be obtained by using the 

Internet— 

1. Search the Federal eRulemaking 

Portal (http://www.regulations.gov); 

2. Visit the FAA’s Regulations and 

Policies Web page at http:// 

www.faa.gov/regulations_policies/ or 

3. Access the Government Printing 

Office’s Web page at http:// 

www.gpoaccess.gov/fr/index.html. 

Copies may also be obtained by 

sending a request (identified by 

amendment or docket number of this 

rulemaking) to the Federal Aviation 

Administration, Office of Rulemaking, 

ARM–1, 800 Independence Avenue, 

SW., Washington, DC 20591, or by 

calling (202) 267–9680. 

B. Comments Submitted to the Docket 

Comments received may be viewed by 

going to http://www.regulations.gov and 

following the online instructions to 

search the docket number for this 

action. Anyone is able to search the 

electronic form of all comments 

received into any of the FAA’s dockets 

by the name of the individual 

submitting the comment (or signing the 

comment, if submitted on behalf of an 

association, business, labor union, etc.). 

C. Small Business Regulatory 

Enforcement Fairness Act 

The Small Business Regulatory 

Enforcement Fairness Act (SBREFA) of 

1996 requires the FAA to comply with 

small entity requests for information or 

advice about compliance with statutes 

and regulations within its jurisdiction. 

A small entity with questions regarding 

this document, may contact its local 

FAA official, or the person listed under 

the FOR FURTHER INFORMATION CONTACT

heading at the beginning of the 

preamble. To find out more about 

SBREFA on the Internet, visit http:// 

www.faa.gov/regulations_policies/ 

rulemaking/sbre_act/. 

Issued in Washington, DC, on February 14, 

2011. 

Frank P. Paskiewicz, 

Acting Deputy Director, Aircraft Certification 

Service. 

[FR Doc. 2011–3777 Filed 2–17–11; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2010–0827; Directorate 

Identifier 2010–CE–029–AD; Amendment 

39–16552; AD 2010–17–18 R1] 

RIN 2120–AA64 

Airworthiness Directives; Air Tractor, 

Inc. Models AT–802 and AT–802A 

Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final regulatory flexibility 

analysis (FRFA). 

SUMMARY: This document incorporates 

the FRFA for Airworthiness Directive 

(AD) 2010–17–18, which applied to 

these products: Air Tractor, Inc. (Air 

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9496 Federal Register / Vol. 76, No. 34 / Friday, February 18, 2011 / Rules and Regulations 

Tractor) Models AT–802 and AT–802A 

airplanes. We have since revised AD 

2010–17–18, which requires you to 

repetitively inspect (using the eddy 

current method) the two outboard 

fastener holes in both of the wing main 

spar lower caps at the center splice joint 

for cracks and repair or replace any 

cracked spar, and changes the safe life 

for certain serial number (SN) ranges. 

Our initial analysis indicated that a 

FRFA was necessary for AD 2010–17– 

18. We issued AD 2010–17–18 without 

the FRFA to immediately address the 

unsafe condition. This action presents 

the FRFA for AD 2010–17–18, which is 

required to be published in the Federal 

Register. 

DATES: This FRFA is effective February 

18, 2011. 

ADDRESSES: 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 (phone: 800–647–5527) is 

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: 

Andrew McAnaul, Aerospace Engineer, 

ASW–150 (c/o MIDO–43), 10100 

Reunion Place, Suite 650, San Antonio, 

Texas 78216; phone: (210) 308–3365; 

fax: (210) 308–3370; e-mail: 

andrew.mcanaul@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Discussion 

On August 11, 2010, we issued AD 

2010–17–18, amendment 39–16412 (75 

FR 52255, August 25, 2010), for all Air 

Tractor Models AT–802 and AT–802A 

airplanes. That AD required you to 

repetitively inspect (using the eddy 

current method) the two outboard 

fastener holes in both of the wing main 

spar lower caps at the center splice joint 

for cracks and repair or replace any 

cracked spar, and changes the safe life 

for certain SN ranges. That AD resulted 

from the FAA’s evaluation of service 

information issued by Air Tractor and 

our determination that we needed to 

add inspections, add modifications, and 

change the safe life for certain SN 

ranges. We issued that AD to detect and 

correct cracks in the wing main spar 

lower cap at the center splice joint, 

which could result in failure of the spar 

cap and lead to wing separation and loss 

of control of the airplane. 

Reason for This Action 

The Regulatory Flexibility Act of 1980 

(Pub. L. 96–354) (RFA) establishes as a 

principle of regulatory issuance that 

agencies shall endeavor, consistent with 

the objective of the rule and of 

applicable statutes, to fit regulatory and 

informational requirements to the scale 

of the businesses, organizations, and 

governmental jurisdictions subject to 

regulation. 

To achieve that principle, the RFA 

requires agencies to solicit and consider 

flexible regulatory proposals and to 

explain the rationale for their actions. 

The RFA covers a wide range of small 

entities, including small businesses, 

not-for-profit organizations, and small 

governmental jurisdictions. 

Agencies must perform a review to 

determine whether a proposed or final 

rule will have a significant economic 

impact on a substantial number of small 

entities. In accordance with Section 608 

of the Regulatory Flexibility Act, an 

agency head may waive or delay 

completion of some or all of the 

requirements of Section 603 by 

providing a written finding that this 

final rule is being promulgated in 

response to an emergency that makes 

compliance or timely compliance with 

the provisions of Section 603 

impracticable. 

Our initial analysis indicated that a 

FRFA was necessary for this action. We 

issued AD 2010–17–18 without the 

FRFA to immediately address the unsafe 

condition. 

On December 16, 2010, we issued AD 

2010–17–18 R1, amendment 39–16552 

(75 FR 82219, December 30, 2010), for 

certain Air Tractor Models AT–802 and 

AT–802A airplanes. This AD retains the 

actions of AD 2010–17–18 and reduces 

the applicability from all SN beginning 

with SN–0001 as required by the 

previous AD to SN–0001 through SN– 

0269. This AD was prompted by our 

evaluation of a comment from David 

Ligon, Air Tractor, and our 

determination that we should reduce 

the applicability from that already 

required by the previous AD. 

This action presents the FRFA, which 

is required to be published in the 

Federal Register. 

Final Regulatory Flexibility Analysis 

On August 25, 2010, the Federal 

Aviation Administration (FAA) issued 

Airworthiness Directive (AD 2010–17– 

18) for Air Tractor Models AT–802 and 

AT–802A airplanes. The FAA 

determined that the final rule was being 

issued in response to an emergency and 

that timely compliance with the 

Regulatory Flexibility Act of 1980 (Pub. 

L. 96–354) (RFA) was impracticable. 

This analysis fulfills the RFA 

requirements. 

Agencies must perform a review to 

determine whether a rule will have a 

significant economic impact on a 

substantial number of small entities. If 

the agency determines that it will, the 

agency must prepare a regulatory 

flexibility analysis as described in the 

RFA. 

This final rule will have a significant 

impact on a substantial number of small 

entities. In accordance with the 

requirements in the RFA, we have 

performed this FRFA and address the 

following requirements: 

(1) A succinct statement of the need 

for, and objectives of, the rule. 

(2) A summary of the significant 

issues raised by the public comments. 

(3) A description and an estimate of 

the number of small entities. 

(4) A description of the projected 

reporting, recordkeeping, and other 

compliance requirements. 

(5) A description of the steps the 

agency has taken to minimize the 

significant adverse economic impact on 

small entities. 

(6) An identification, to the extent 

practicable, of all relevant Federal rules 

which may duplicate, overlap, or 

conflict with the final rule. 

Next, we address each of those 

individual requirements. 

(1) A succinct statement of the need 

for, and objectives of, the rule. 

This AD will improve the ability of 

operators flying Models Air Tractor 802 

and 802A airplanes to discover and to 

correct cracks in the wing main spar 

lower cap at the center splice joint, 

which could result in the failure of the 

spar cap and lead to the wing separating 

from the airplane body. 

The FAA is responsible for the safety 

of flight in the United States and for the 

safety of U.S.-registered aircraft and U.S. 

operations. The FAA is also responsible 

for issuing rules affecting the safety of 

air commerce and national security. The 

FAA’s authority to issue the rules on 

aviation safety is found in Title 49 of the 

United States Code. Subtitle I, section 

106(g) describes the authority of the 

FAA Administrator. Subtitle VII, 

Aviation Programs, describes in more 

detail the scope of the agency’s 

authority. Section 40101(d)(1) provides 

that the Administrator shall consider in 

the public interest, among other matters, 

assigning, maintaining, and enhancing 

safety and security as the highest 

priorities in air commerce. Further, the 

FAA has broad authority under section 

44701(a)(5) to prescribe regulations 

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Federal Register / Vol. 76, No. 34 / Friday, February 18, 2011 / Rules and Regulations 9497 

governing the practices, methods, and 

procedures the Administrator finds 

necessary for safety in air commerce and 

national security. The FAA finds this 

action necessary to prevent a potential 

hazard to Air Tractor Models AT–802 

and AT–802A airplanes engaged 

primarily in agricultural and firefighting 

operations. 

(2) A summary of the significant 

issues raised by the public comments. 

The FAA received one comment on 

this final rule. Air Tractor commented 

that there should be no additional 

inspections required for their AT–802 

and AT–802A airplanes with serial 

numbers greater than 0269. We 

concurred and on December 30, 2010, 

issued AD 2010–17–18 R1 to reduce the 

applicability of AD 2010–17–18 only to 

Models AT–802 and AT–802A serial 

numbers 0001 through 0269. 

(3) A description and an estimate of 

the number of small entities. 

There are 52 of these affected Air 

Tractor airplanes operating in the 

United States. Of these 52 airplanes, 46 

are operated by the private sector and 6 

are operated by the United States State 

Department. Of the 46 operated by the 

34 entities in the private sector, 25 

operate only 1 airplane, 1 operates 2 

airplanes, 5 operate 3 airplanes, and 1 

operates 4 airplanes. The Small 

Business Administration classifies 

operators with less than 1,500 

employees as small businesses. All of 

the private entities are small entities 

with fewer than 1,500 employees. 

(4) A description of the projected 

reporting, recordkeeping, and other 

compliance requirements. 

This final rule changes the existing 

requirement that any inspection finding 

a crack must be reported to the FAA by 

requiring the operator to use a specific 

one-page reporting form that has been 

approved by the Office of Management 

and Budget for that report. 

The final rule requires operators of 

Air Tractor serial numbers AT–802– 

0092 through 0101 and AT–802A–0092 

through 0101: 

• To perform, using the eddy current 

method, two inspections at 1,700 timein-service (TIS) hours, at 2,500 TIS 

hours, and at 3,300 TIS hours (at a cost 

of $650 an inspection) of the two 

outboard fastener holes in both of the 

wing main spar lower caps at the center 

splice joint for cracks and to repair or 

replace any cracked spar. 

• To install at 4,100 TIS hours a 

center web plate and splice blocks (at a 

cost of $25,500). 

Operators of Air Tractor serial 

numbers AT–802–0102 through 0178 

and AT–802A–0102 through 0178 to 

perform using the eddy current method, 

two inspections at 5,500 TIS hours and 

at 6,600 TIS hours (at a cost of $650 an 

inspection) of the two outboard fastener 

holes in both of the wing main spar 

lower caps at the center splice joint for 

cracks and to repair or replace any 

cracked spar. 

We determined that an average AT– 

802 or AT–802A lasts 40 years before it 

leaves service in the United States. We 

also determined that it flies an average 

of 450 hours a year. Thus, an AT–802 

or AT–802A accumulates an average of 

18,000 TIS hours before it leaves service 

in the United States. All of the affected 

airplanes (AT–802 0092–0178 and AT– 

802A 0092–0178) were built between 

2000 and 2004. 

The baseline from which the FAA 

calculated the incremental costs to 

comply with Air Tractor AD 2010–17– 

18 is compliance with the previous Air 

Tractor AD (AD 2010–13–08) published 

in the Federal Register on June 23, 

2010. This earlier AD addressed Air 

Tractor Airplane Model AT–802 serial 

numbers 0001 through 0091 and Model 

AT–802A serial numbers 0001 through 

0091. 

This AD imposed no new 

requirements beyond those in AD 2010– 

13–08 on Air Tractor Models AT–802 

serial numbers 0001 through 0091 and 

Model AT–802A serial numbers 0001 

through 0091. 

As previously noted, this AD also 

addressed Air Tractor Model AT–802 

serial numbers 0179 forward and Model 

AT–802A serial numbers 0179 forward. 

However, the December 30, 2010, AD 

removed these airplanes from 

compliance with this AD. 

Thus, in comparison with AD 2010– 

13–08, this AD affects Model AT–802 

serial numbers 0092 through 0178 and 

Model AT–802A serial numbers 0092 

through 0178 in service in the United 

States. 

For the purposes of this analysis, 

there are two different categories within 

each of these two models. Category 1 

consists of Model AT–802 serial 

numbers 0092 through 0101 and Model 

AT–802A serial numbers 0092 through 

0101, which were manufactured in 

2000. Category 2 consists of Model AT– 

802 serial numbers 0102 through 0178 

and Model AT–802A serial numbers 

0102 through 0178 manufactured 

between 2000 through 2004. As seen in 

Table 1, there are only 6 category 1 

airplanes and 40 category 2 airplanes. 

TABLE 1—NUMBERS OF AFFECTED

AT–802 AND AT–802A AIRPLANES

IN PRIVATE OPERATIONS BY CATEGORY AND BY YEAR OF MANUFACTURE

Manufacture 

year 

Category 

Total 

1 2 

2000 .................. 6 4 10 

2001 .................. ............ 10 10 

2002 .................. ............ 6 6 

2003 .................. ............ 13 13 

2004 .................. ............ 7 7 

Total ........... 6 40 46 

For category 1 airplanes, this AD 

requires that the operator must perform 

three eddy current inspections (at 1,700 

TIS hours, at 2,500 TIS hours, and at 

3,300 TIS hours), each inspection 

costing $650. However, as all of these 

airplanes were manufactured in 2000 

and, given an average of 450 annual TIS 

hours, they are already, on average, at 

4,050 TIS hours. Nevertheless, the FAA 

assumes that these six airplanes will 

need one inspection, which will be 

taken in 2011. 

The AD also reduced their spar cap 

maximum safe life from 8,163 TIS hours 

to 4,100 TIS hours. However, the 

operator can extend the spar cap 

maximum safe life from 4,100 hours to 

8,000 hours by spending $25,500 to 

install a center web plate and splice 

blocks. The FAA assumes that all of 

these installations will occur in 2012. 

Finally, although the spar cap has to be 

replaced (at a cost of $81,175) by 8,000 

TIS hours, this is required under AD 

2010–13–08. 

For category 2 airplanes, this AD 

reduced their spar cap maximum safe 

life from 8,163 TIS hours to 5,500 TIS 

hours. However, if the operator 

performs two eddy current inspections 

(at 5,500 TIS hours and at 6,600 TIS 

hours), each inspection costing $650, 

the spar cap maximum safe life can be 

extended to 8,000 TIS hours. Given an 

average of 450 annual TIS hours, these 

airplanes will have their first inspection 

(at 5,500 TIS hours) 12 years after they 

were manufactured and will have their 

second inspection 3 years later (after 

having an average of 1,350 TIS hours 

during those 3 years). As these airplanes 

were manufactured between late 2000 

and 2004, the FAA assumes that the 

2000 airplanes will have their first 

inspection in 2012 and the second 

inspection in 2015; the 2001 airplanes 

will have their first inspection in 2013 

and the second inspection in 2016, etc. 

The FAA uses a 10-year period of 

analysis (2011–2020) because that is 

when nearly all of the compliance 

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expenditures will be made. The FAA 

also uses a 7 percent discount rate to 

calculate the present values of the costs. 

The AD does not require any 

additional inspections after the 

replacement spar has been installed 

because the replacement spars are 

higher quality than the original 

equipment. 

Thus, the AD will impose two types 

of compliance costs. The first are the 

costs from the inspections. The second 

are the costs to the category 1 Air 

Tractor operators that will need to 

install a center web plate and splice 

blocks at 4,100 TIS hours. 

As seen in Table 2, the cost to comply 

with the AD requirements for 

inspections during the ten-year period 

would be $55,900, which, using a 7 

percent discount rate, has a present 

value of $39,260. 

TABLE 2—TOTAL AND PRESENT VALUE COMPLIANCE COSTS TO COMPLY WITH THE INSPECTIONS REQUIRED BY THE AD 

[2011–2020] 

Manufacture year 

Number of inspections by year 

Total 

2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 

2000 (Cat 1) ............. 6 0 0 0 0 0 0 0 0 0 6 

2000 (Cat 2) ............. 0 4 0 0 4 0 0 0 0 0 8 

2001 ......................... 0 0 10 0 0 10 0 0 0 0 20 

2002 ......................... 0 0 0 6 0 0 6 0 0 0 12 

2003 ......................... 0 0 0 0 13 0 0 13 0 0 26 

2004 ......................... 0 0 0 0 0 7 0 0 7 0 14 

Total .................. 6 4 10 6 17 17 6 13 7 0 86 

Total Cost .......... $3,900 $2,600 $6,500 $3,900 $11,050 $11,050 $3,900 $8,450 $4,550 $0 $55,900 

Present Value ... $3,645 $2,271 $5,306 $2,975 $7,878 $7,363 $2,429 $4,918 $2,475 $0 $39,260 

Each of the 6 category 1 Air Tractor 

airplane operators will need to spend 

$25,500 to install the center web plate 

and splice blocks in 2012, which has a 

present value of $22,273 using a 

7 percent discount rate. The total cost to 

install this equipment on these 6 

airplanes is $153,000, which has a 

present value of $133,638 using a 

7 percent discount rate. 

Thus, the total cost would be 

$208,900, which has a present value of 

$172,898 using a 7 percent discount 

rate. 

However, these costs are unequally 

distributed across the 34 operators. The 

six category 1 Air Tractor airplane 

operators will need to spend $26,150 an 

airplane while the category 2 Air 

Tractor airplane operators will need to 

spend between $650 and $1,300 an 

airplane. 

(5) A description of the steps the 

agency has taken to minimize the 

significant economic impact of the final 

rule on small entities. 

The FAA is responsible for the safety 

of U.S.-registered aircraft and U.S. 

operators. The FAA has not identified 

any significant alternatives to this final 

rule that accomplish the stated 

objectives of applicable statutes, and 

which minimize any significant 

economic impact of the final rule SFAR 

on small entities. 

(6) An identification, to the extent 

practicable, of all relevant Federal rules 

which may duplicate, overlap, or 

conflict with the final rule. 

The FAA knows of no other Federal 

rules which duplicate, overlap, or 

conflict with the final rule. 

Determination of Significant Impact 

As discussed in the compliance cost 

section, all of these operators are small 

businesses. Further, nearly all of them 

are privately held businesses that do not 

file reports that the FAA can access to 

determine annual revenues. However, 

the FAA can determine that the average 

value of an Air Tractor Model AT–800A 

serial number 0091–0101 is about 

$650,000. This rule requires the 6 

operators of these airplanes to spend 

about 4 percent ($25,500) of the value of 

the airplane on a repair. The FAA 

believes that this magnitude of an 

expenditure could place these six 

operators in some financial difficulty. 

Therefore, this final rule will have a 

significant economic impact on a 

substantial number of small entities. 

Issued in Kansas City, Missouri, on 

February 11, 2011. 

John R. Colomy, 

Acting Manager, Small Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. 2011–3653 Filed 2–17–11; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2010–0379; Directorate 

Identifier 2009–NM–210–AD; Amendment 

39–16609; AD 2011–04–10] 

RIN 2120–AA64 

Airworthiness Directives; The Boeing 

Company Model 737–300, –400, and 

–500 Series 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 all Model 737–300, 

–400, and –500 series airplanes. That 

AD currently requires inspecting to 

determine if certain carriage spindles 

are installed, repetitive inspections for 

corrosion and indications of corrosion 

on affected carriage spindles, and if 

necessary, related investigative and 

corrective actions. That AD also 

provides an optional terminating action. 

This new AD mandates the optional 

terminating action, which eliminates the 

need for the repetitive inspections. This 

AD results from reports of corrosion 

found on carriage spindles that are 

located on the outboard trailing edge 

flaps. We are issuing this AD to detect 

and correct corrosion of the carriage 

spindle, which could result in fracture. 

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