Federal Register / Vol. 73, No. 196 / Wednesday, October 8, 2008 / Proposed Rules 58903 

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. 

Issued in Renton, Washington, on 

September 26, 2008. 

Michael Kaszycki, 

Acting Manager, Transport Airplane 

Directorate, Aircraft Certification Service. 

[FR Doc. E8–23821 Filed 10–7–08; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2008–1071; Directorate 

Identifier 2008–NM–093–AD] 

RIN 2120–AA64 

Airworthiness Directives; Boeing 

Model 747 Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), Department of 

Transportation (DOT). 

ACTION: Notice of proposed rulemaking 

(NPRM). 

SUMMARY: The FAA proposes to 

supersede an existing airworthiness 

directive (AD) that applies to certain 

Boeing Model 747 airplanes. The 

existing AD currently requires repetitive 

inspections to detect evidence of wear 

damage in the area at the interface 

between the vertical stabilizer seal and 

fuselage skin, and corrective actions, if 

necessary. The existing AD also 

provides for an optional terminating 

action for the repetitive inspections. For 

all airplanes, this proposed AD would 

require doing repetitive inspections for 

wear damage and cracks of the fuselage 

skin in the interface area of the vertical 

stabilizer seal and fuselage skin, doing 

a detailed inspection for wear damage 

and cracks of the surface of any skin 

repair doubler in the area, and doing 

corrective actions. For airplanes on 

which the fuselage skin has been 

blended to remove wear damage, this 

proposed AD would require doing 

repetitive external detailed inspections 

or high frequency eddy current 

inspections for cracks of the blended 

area of the fuselage skin, and corrective 

actions if necessary. This proposed AD 

results from reports of wear damage on 

airplanes with fewer than 8,000 total 

flight cycles. In addition, there have 

been three reports of skin wear damage 

on airplanes that applied BMS 10–86 

Teflon-filled coating (terminating action 

per AD 2002–26–15). We are issuing 

this AD to detect and correct wear 

damage and cracks of the fuselage skin 

in the interface area of the vertical 

stabilizer seal and fuselage skin in 

sections 46 and 48, which could cause 

in-flight depressurization of the 

airplane. 

DATES: We must receive comments on 

this proposed AD by November 24, 

2008. 

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 20590, between 9 a.m. 

and 5 p.m., Monday through Friday, 

except Federal holidays. 

For service information identified in 

this AD, contact Boeing Commercial 

Airplanes, P.O. Box 3707, Seattle, 

Washington 98124–2207. 

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 

(telephone 800–647–5527) is in the 

ADDRESSES section. Comments will be 

available in the AD docket shortly after 

receipt. 

FOR FURTHER INFORMATION CONTACT: Ivan 

Li, Aerospace Engineer, Airframe 

Branch, ANM–120S, FAA, Seattle 

Aircraft Certification Office, 1601 Lind 

Avenue, SW., Renton, Washington 

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

fax (425) 917–6590. 

SUPPLEMENTARY INFORMATION: 

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–2008–1071; Directorate Identifier 

2008–NM–093–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 

On December 24, 2002, we issued AD 

2002–26–15, amendment 39–13003 (68 

FR 476, January 6, 2003), for certain 

Boeing Model 747 series airplanes. That 

AD requires repetitive inspections to 

detect evidence of skin wear damage in 

the interface area of the vertical 

stabilizer seal and fuselage skin, and 

corrective actions, if necessary. The 

existing AD also provides for an 

optional terminating action for the 

repetitive inspections. That AD resulted 

from reports of wear damage at the 

interface area of the vertical stabilizer 

seal and fuselage skin in sections 46 and 

48. We issued that AD to detect and 

correct wear damage of the fuselage 

skin, which could result in thinning and 

cracking of the fuselage skin, and 

consequent in-flight depressurization of 

the airplane. 

Actions Since Existing AD Was Issued 

Since we issued AD 2002–26–15, we 

have received several reports of skin 

wear damage on airplanes with less than 

8,000 total flight cycles. As a result, 

Boeing has revised the initial inspection 

threshold of the repetitive inspections to 

20,000 total flight hours. In addition, 

there have been three reports of skin 

wear damage on airplanes that have 

received the Boeing Material 

Specifications (BMS) 10–86 Teflonfilled coating application (terminating 

action per AD 2002–26–15). We have 

concluded that the one-time Teflonfilled coating application does not 

provide the necessary skin wear 

resistance; therefore, the terminating 

action no longer terminates the 

repetitive inspections. The requirements 

of 2002–26–15 do not adequately 

address the identified unsafe condition 

of that AD. 

Relevant Service Information 

We have reviewed Boeing Alert 

Service Bulletin 747–53A2478, Revision 

1, dated March 27, 2008. The service 

bulletin describes the following 

procedures: 

• For all airplanes: Do repetitive 

external inspections for wear damage 

and cracks of the fuselage skin at the 

interface area of the vertical stabilizer 


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58904 Federal Register / Vol. 73, No. 196 / Wednesday, October 8, 2008 / Proposed Rules 

seal and fuselage skin, and do a detailed 

inspection for wear damage and cracks 

of the surface of any repair doubler 

installed in the area. 

• For airplanes on which the fuselage 

skin has been blended to remove wear 

damage: Do repetitive external detailed 

inspections or high frequency eddy 

current inspections for cracks of the 

blended area of the fuselage skin. 

• If no wear damage or crack is found: 

Before further flight, apply BMS 10–86 

Teflon-filled coating. 

• If any wear damage or crack is 

found: Before further flight, measure the 

depth of the wear and location, repair 

any wear damage and crack, and apply 

BMS 10–86 Teflon-filled coating. 

Accomplishing the actions specified 

in the service information is intended to 

adequately address the unsafe 

condition. 

FAA’s Determination and Requirements 

of the Proposed AD 

We have evaluated all pertinent 

information and identified an unsafe 

condition that is likely to develop on 

other airplanes of the same type design. 

For this reason, we are proposing this 

AD, which would supersede AD 2002– 

26–15. This proposed AD would retain 

the requirements of that AD and also 

require accomplishing the actions 

described previously, except as 

discussed under ‘‘Differences Between 

the Proposed AD and the Service 

Bulletin.’’ 

Differences Between the Proposed AD 

and Service Bulletin 

The service bulletin specifies to 

contact the manufacturer for actions if 

corrosion resistant steel rubstrips are 

installed in the interface area of the 

vertical stabilizer seal and fuselage skin, 

but this proposed AD would require 

contacting the FAA for inspections 

using a method that we approve. 

Costs of Compliance 

There are about 917 airplanes of the 

affected design in the worldwide fleet. 

The following table provides the 

estimated costs for U.S. operators to 

comply with this proposed AD. 

ESTIMATED COSTS

Action Work hours Average labor 

rate per hour Parts Cost per airplane 

Number of 

U.S.-registered 

airplanes 

Fleet cost 

Inspection (required 

by AD 2002–26– 

15).

12 $80 None ......................... $960, per inspection 

cycle.

253 $242,880, per inspection cycle. 

Inspection and application of BMS 10– 

86 Teflon-filled 

coating (new proposed action).

8 80 None ......................... $640, per inspection 

cycle.

165 $105,600, per inspection cycle. 

Authority for This Rulemaking 

Title 49 of the United States Code 

specifies the FAA’s authority to issue 

rules on aviation safety. Subtitle I, 

Section 106, describes the authority of 

the FAA Administrator. Subtitle VII, 

Aviation Programs, describes in more 

detail the scope of the Agency’s 

authority. 

We are issuing this rulemaking under 

the authority described in Subtitle VII, 

Part A, Subpart III, Section 44701, 

‘‘General requirements.’’ Under that 

section, Congress charges the FAA with 

promoting safe flight of civil aircraft in 

air commerce by prescribing regulations 

for practices, methods, and procedures 

the Administrator finds necessary for 

safety in air commerce. This regulation 

is within the scope of that authority 

because it addresses an unsafe condition 

that is likely to exist or develop on 

products identified in this rulemaking 

action. 

Regulatory Findings 

We have determined that this 

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 that the 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); 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 proposed AD and placed it in the 

AD docket. See the ADDRESSES section 

for a location to examine the regulatory 

evaluation. 

List of Subjects in 14 CFR Part 39 

Air transportation, Aircraft, Aviation 

safety, 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 Federal Aviation 

Administration (FAA) amends § 39.13 

by removing amendment 39–13003 (68 

FR 476, January 6, 2003) and adding the 

following new airworthiness directive 

(AD): 

Boeing: Docket No. FAA–2008–1071; 

Directorate Identifier 2008–NM–093–AD. 

Comments Due Date 

(a) The FAA must receive comments on 

this AD action by November 24, 2008. 

Affected ADs 

(b) This AD supersedes AD 2002–26–15. 

Applicability 

(c) This AD applies to Boeing Model 747– 

100, 747–100B, 747–100B SUD, 747–200B, 

747–200C, 747–200F, 747–300, 747–400, 

747–400D, 747–400F, 747SR, and 747SP 

series airplanes, certificated in any category, 

as identified in Boeing Alert Service Bulletin 

747–53A2478, Revision 1, dated March 27, 

2008. 


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Federal Register / Vol. 73, No. 196 / Wednesday, October 8, 2008 / Proposed Rules 58905 

Unsafe Condition 

(d) This AD results from reports of skin 

wear damage on airplanes with fewer than 

8,000 total flight cycles. In addition, there 

have been three reports of skin wear damage 

on airplanes on which BMS 10–86 Teflonfilled coating was applied (terminating action 

per AD 2002–26–15). We are issuing this AD 

to detect and correct wear damage and cracks 

of the fuselage skin in the interface area of 

the vertical stabilizer seal and fuselage skin 

in sections 46 and 48, which could cause inflight depressurization of the airplane. 

Compliance 

(e) You are responsible for having the 

actions required by this AD performed within 

the compliance times specified, unless the 

actions have already been done. 

Requirements of AD 2002–26–15 

Inspections for Damage/Corrective Actions 

(f) For airplanes identified in Boeing Alert 

Service Bulletin 747–53A2478, dated 

February 7, 2002: Prior to the accumulation 

of 15,000 total flight cycles, or within 1,200 

flight cycles after February 10, 2003 (the 

effective date of AD 2002–26–15), whichever 

occurs later, perform a detailed inspection to 

detect evidence of wear damage of the 

fuselage skin at the interface area of the 

vertical stabilizer seal and fuselage skin, per 

the service bulletin. 

(1) If no wear damage of the fuselage skin 

is detected or any existing blendout is within 

the structural repair manual (SRM) allowable 

damage limits: Repeat the detailed inspection 

at intervals not to exceed 6,000 flight cycles. 

(2) If any wear damage of the fuselage skin 

is detected or any existing blendout exceeds 

the allowable damage limits specified in the 

SRM: Before further flight, repair the vertical 

stabilizer seal interface and refinish the skin 

with BMS 10–86 Teflon-filled coating, per 

the alert service bulletin. Accomplishment of 

the repair and refinishing is terminating 

action for the repetitive inspections required 

by paragraph (f)(1) of this AD. 

Note 1: For the purposes of this AD, a 

detailed inspection is defined as: ‘‘An 

intensive visual examination of a specific 

structural area, system, installation, or 

assembly to detect damage, failure, or 

irregularity. Available lighting is normally 

supplemented with a direct source of good 

lighting at intensity deemed appropriate by 

the inspector. Inspection aids such as mirror, 

magnifying lenses, etc., may be used. Surface 

cleaning and elaborate access procedures 

may be required.’’ 

Previously Accomplished Inspections and 

Terminating Action 

(g) For airplanes identified in Boeing Alert 

Service Bulletin 747–53A2478, dated 

February 7, 2002: Inspections and 

terminating action done before February 10, 

2003, per Boeing Service Bulletin 747–53– 

2192, dated July 21, 1981, are acceptable for 

compliance with the corresponding actions 

required by paragraph (f) of this AD, 

provided BMS 10–86 Teflon-filled coating 

was used, and the new allowable damage 

limits specified in Boeing Alert Service 

Bulletin 747–53A2478, dated February 7, 

2002, are met. 

New Requirements of This AD 

New Service Bulletin Revision 

(h) The term ‘‘service bulletin,’’ as used in 

paragraphs (i) through (l) of this AD, means 

Boeing Alert Service Bulletin 747–53A2478, 

Revision 1, dated March 27, 2008, unless 

otherwise specified. 

New Repetitive Inspections 

(i) Except as provided by paragraph (j) of 

this AD: At the applicable times specified in 

Table 1 of this AD, do the actions specified 

in paragraphs (i)(1) and (i)(2) of this AD, as 

applicable. Accomplishing the initial 

inspection specified in paragraph (i) 

terminates the requirements of paragraph (f) 

of this AD. 

(1) For all airplanes: Do the actions 

specified in paragraphs (i)(1)(i) and (i)(1)(ii) 

of this AD, as applicable. 

(i) Do repetitive external detailed 

inspections for wear damage and cracks of 

the fuselage skin in the interface area of the 

vertical stabilizer seal and fuselage skin, in 

accordance with the Accomplishment 

Instructions of the service bulletin. 

(ii) Where a skin repair doubler is present 

in the interface area of the vertical stabilizer 

seal and fuselage skin, do a detailed 

inspection for wear damage and cracks of the 

surface of the repair doubler. 

(2) For airplanes that have reduced skin 

thickness in Section 46 due to blending 

without reinforcement: Do repetitive external 

detailed inspections or high frequency eddy 

(HFEC) current inspections for cracks of the 

blended area of the fuselage skin, in 

accordance with the Accomplishment 

Instructions of the service bulletin. 

TABLE 1—COMPLIANCE TIMES

Action 

Compliance time 

(whichever occurs later) Repeat interval 

(not to exceed) 

Threshold Grace period 

For actions required by 

paragraph (i)(1) of this AD.

Prior to the accumulation of 20,000 total flight hours 

since the date of issuance of the original airworthiness certificate or the date of issuance of the original export certificate of airworthiness, or within 

7,500 flight hours after the last inspection of this 

AD, whichever occurs later.

Within 6,000 flight hours 

after the effective date of 

this AD.

7,500 flight hours. 

For actions required by 

paragraph (i)(2) of this AD.

Prior to the accumulation of 20,000 total flight cycles 

since the date of issuance of the original airworthiness certificate or the date of issuance of the original export certificate of airworthiness, or within 

6,000 flight cycles after the initial blend, whichever 

occurs later.

Within 1,000 flight cycles 

after the effective date of 

this AD.

1,200 flight cycles for external detailed inspection, or 6,000 flight cycles for HFEC inspection. 

Exception to the Repetitive Inspections 

(j) If corrosion-resistant steel rubstrips are 

installed in the interface area of the vertical 

stabilizer seal and fuselage skin: Within the 

applicable compliance times specified in 

paragraph (i) of this AD, inspect the fuselage 

skin using a method approved in accordance 

with the procedures specified in paragraph 

(m) of this AD. 

For No Wear Damage or Cracks Found: 

Apply Teflon 

(k) If no wear damage or crack is found in 

the fuselage skin during any inspection 

required by paragraph (i) of this AD: Before 

further flight, apply Boeing Material 

Specifications (BMS) 10–86 Teflon-filled 

coating in accordance with the 

Accomplishment Instructions of the service 

bulletin. 

For Any Wear Damage or Crack Found: 

Applicable Corrective Actions 

(l) If any wear damage or crack is found in 

the fuselage skin during any inspections 

required by paragraph (i) of this AD: Before 

further flight, after the inspection required by 

paragraph (i), do the actions specified in 

paragraphs (l)(1), (l)(2), and (l)(3) of this AD, 

in accordance with the Accomplishment 

Instructions of the service bulletin. 

(1) Measure the depth of the wear and 

record the location. 

(2) Repair any wear damage and any crack. 


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58906 Federal Register / Vol. 73, No. 196 / Wednesday, October 8, 2008 / Proposed Rules 

(3) Apply BMS 10–86 Teflon-filled coating. 

Alternative Methods of Compliance (AMOCs) 

(m)(1) The Manager, Seattle Aircraft 

Certification Office (ACO), FAA, ATTN: Ivan 

Li, Aerospace Engineer, Airframe Branch, 

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

Avenue SW., Renton, Washington 98057– 

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

917–6590; has the authority to approve 

AMOCs for this AD, if requested using the 

procedures found in 14 CFR 39.19. 

(2) To request a different method of 

compliance or a different compliance time 

for this AD, follow the procedures in 14 CFR 

39.19. Before using any approved AMOC on 

any airplane to which the AMOC applies, 

notify your appropriate principal inspector 

(PI) in the FAA Flight Standards District 

Office (FSDO), or lacking a PI, your local 

FSDO. 

(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 an 

Authorized Representative for the Boeing 

Commercial Airplanes Delegation Option 

Authorization Organization who 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. 

Issued in Renton, Washington, on 

September 26, 2008. 

Michael Kaszycki, 

Acting Manager, Transport Airplane 

Directorate, Aircraft Certification Service. 

[FR Doc. E8–23824 Filed 10–7–08; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2008–1070; Directorate 

Identifier 2008–NM–087–AD] 

RIN 2120–AA64 

Airworthiness Directives; Boeing 

Model 737–100, –200, –200C, –300, 

–400, and –500 Series 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 

Boeing Model 737–100, –200, –200C, 

–300, –400, and –500 series airplanes. 

For all airplanes, this proposed AD 

would require repetitive overhaul of the 

retract actuator beam of the main 

landing gear (MLG). For certain 

airplanes, this proposed AD would 

require repetitive inspections for 

damage of the retract actuator beam, and 

related investigative and corrective 

actions if necessary. This proposed AD 

results from reports of broken retract 

actuator beams of the MLG and the 

subsequent failure of the MLG to fully 

retract. We are proposing this AD to 

detect and correct broken retract 

actuator beams of the MLG, which could 

cause damage to the beam arm, 

hydraulic tubing, and flight control 

cables. Damage to the flight control 

cables could result in loss of control of 

the airplane. 

DATES: We must receive comments on 

this proposed AD by November 24, 

2008. 

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 20590, between 9 a.m. 

and 5 p.m., Monday through Friday, 

except Federal holidays. 

For service information identified in 

this AD, contact Boeing Commercial 

Airplanes, P.O. Box 3707, Seattle, 

Washington 98124–2207. 

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 

(telephone 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, 

1601 Lind Avenue, SW., Renton, 

Washington 98057–3356; telephone 

(425) 917–6440; fax (425) 917–6590. 

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–2008–1070; Directorate Identifier 

2008–NM–087–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 reports of broken 

retract actuator beams of the main 

landing gear (MLG) and the subsequent 

failure of the MLG to fully retract. In 

one incident, hydraulic system A 

became unserviceable. In another 

incident, the flightcrew declared an 

emergency and made an air turn-back. 

For all the reports of MLG retract 

actuator beams that broke in service, the 

MLG fell to the down-and-locked 

position, and landings were normal. 

Investigation revealed that proper 

procedures were not followed during 

overhaul, resulting in stress corrosion 

cracking initiating from small corrosion 

pits that were not entirely removed. In 

one incident, cracking initiated in an 

area of heat damage/burning caused by 

incorrect stylus cadmium plating. 

Broken retract actuator beams of the 

MLG, if not corrected, could cause 

damage to the beam arm, hydraulic 

tubing, and flight control cables. 

Damage to the flight control cables 

could result in loss of control of the 

airplane. 

Relevant Service Information 

We have reviewed Boeing Service 

Bulletin 737–32A1355, Revision 2, 

dated March 5, 2008. The service 

bulletin describes the procedures and 

compliance times specified in the 

following service information table. 


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