Federal Register / Vol. 73, No. 153 / Thursday, August 7, 2008 / Proposed Rules 45895 

inspections described in the revisions. In this 

situation, to comply with 14 CFR 91.403(c), 

the operator must request approval for an 

alternative method of compliance (AMOC) 

according to paragraph (k) of this AD. The 

request should include a description of 

changes to the required inspections that will 

ensure the continued operational safety of 

the airplane. 

Unsafe Condition 

(d) This AD results from fuel system 

reviews conducted by the manufacturer. We 

are issuing this AD to prevent electrical 

current from flowing through a motor 

operated valve (MOV) actuator into a fuel 

tank, which could create a potential ignition 

source inside the fuel tank. This condition, 

in combination with flammable fuel vapors, 

could result in a fuel tank explosion and 

consequent loss of the airplane. 

Compliance 

(e) Comply with this AD within the 

compliance times specified, unless already 

done. 

Inspection 

(f) Within 60 months after the effective 

date of this AD, do an inspection of the MOV 

actuators of the main and center fuel tanks 

for part number MA20A1001–1, in 

accordance with the Accomplishment 

Instructions of Boeing Alert Service Bulletin 

777–28A0034, dated August 2, 2007. 

Replacement 

(g) If any part number MA20A1001–1 is 

found during the inspection required by 

paragraph (f) of this AD, within 60 months 

after the effective date of this AD, do the 

actions specified in paragraphs (g)(1) and 

(g)(2) of this AD by accomplishing all the 

applicable actions specified in the 

Accomplishment Instructions of Boeing Alert 

Service Bulletin 777–28A0034, dated August 

2, 2007. Do all applicable corrective actions 

before further flight. 

(1) Replace the MOV actuator with a new 

MOV actuator, part number MA030A1001. 

(2) Measure the electrical resistance of the 

bond from the adapter plate to the airplane 

structure, and do all applicable corrective 

actions. 

Airworthiness Limitations (AWLs): Revision 

for AWL No. 28–AWL–19 and 28–AWL–20 

(h) Concurrently with accomplishing the 

actions required by paragraph (g) of this AD, 

revise the AWLs section of the Instructions 

for Continued Airworthiness (ICA) by 

incorporating AWL No. 28–AWL–19 and No. 

28–AWL–20 of Subsection E of Section 9, 

Revision 28, dated February 2006, of the 

Boeing 777 Maintenance Planning Data 

(MPD) Document, D622W001–9. 

No Alternative Critical Design Configuration 

Control Limitations (CDCCLs) 

(i) After accomplishing the action specified 

in paragraph (h) of this AD, no alternative 

CDCCLs may be used unless the CDCCLs are 

approved as an AMOC in accordance with 

the procedures specified in paragraph (k) of 

this AD. 

Terminating Action for AWLs Revision 

(j) Incorporating AWL No. 28–AWL–19 and 

No. 28–AWL–20 into the AWLs section of the 

ICA in accordance with paragraph (g)(2) of 

AD 2008–11–13, amendment 39–15536, 

terminates the action required by paragraph 

(h) of this AD. 

Alternative Methods of Compliance 

(AMOCs) 

(k)(1) The Manager, Seattle ACO, FAA, 

ATTN: Margaret Langsted, Aerospace 

Engineer, Propulsion Branch, ANM–140S, 

FAA, SACO, 1601 Lind Avenue, SW., 

Renton, Washington 98057–3356; telephone 

(425) 917–6500; 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. 

Issued in Renton, Washington, on July 29, 

2008. 

Ali Bahrami, 

Manager, Transport Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. E8–18211 Filed 8–6–08; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2008–0846; Directorate 

Identifier 2008–NM–045–AD] 

RIN 2120–AA64 

Airworthiness Directives; Boeing 

Model 757–200, 757–200PF, and 757–

300 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 certain 

Boeing Model 757–200, 757–200PF, and 

757–300 series airplanes. This proposed 

AD would require, for certain airplanes, 

measuring the electrical bond resistance 

at certain stations and doing any 

applicable repair; installing support 

brackets for the hot short protector and 

new support clamps for the wire 

bundles; installing the equipment of the 

hot short protector; and modifying an 

existing wire bundle and installing a 

new wire bundle. This proposed AD 

would also require, for certain other 

airplanes, measuring the electrical bond 

resistance at certain stations, measuring 

the electrical bonding resistance 

between the hot short protector and rear 

spar web, and doing any applicable 

repair. This proposed AD also would 

require revising the Airworthiness 

Limitations section of the Instructions 

for Continued Airworthiness. This 

proposed AD results from fuel system 

reviews conducted by the manufacturer. 

We are proposing this AD to prevent the 

center fuel tank densitometer from 

overheating and becoming a potential 

ignition source inside the fuel tank, 

which, in combination with flammable 

fuel vapors, could result in a center fuel 

tank explosion and consequent loss of 

the airplane. 

DATES: We must receive comments on 

this proposed AD by September 22, 

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: Jen 

Pei, Aerospace Engineer, Systems and 

Equipment Branch, ANM–130S, FAA, 

Seattle Aircraft Certification Office, 

1601 Lind Avenue, SW., Renton, 

Washington 98057–3356; telephone 

(425) 917–6409; fax (425) 917–6590. 

SUPPLEMENTARY INFORMATION: 


rmajette on PRODPC74 with PROPOSALS
45896 Federal Register / Vol. 73, No. 153 / Thursday, August 7, 2008 / Proposed Rules 

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–2008–0846; Directorate Identifier 

2008–NM–045–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 

The FAA has examined the 

underlying safety issues involved in fuel 

tank explosions on several large 

transport airplanes, including the 

adequacy of existing regulations, the 

service history of airplanes subject to 

those regulations, and existing 

maintenance practices for fuel tank 

systems. As a result of those findings, 

we issued a regulation titled ‘‘Transport 

Airplane Fuel Tank System Design 

Review, Flammability Reduction and 

Maintenance and Inspection 

Requirements’’ (66 FR 23086, May 7, 

2001). In addition to new airworthiness 

standards for transport airplanes and 

new maintenance requirements, this 

rule included Special Federal Aviation 

Regulation No. 88 (‘‘SFAR 88,’’

Amendment 21–78, and subsequent 

Amendments 21–82 and 21–83). 

Among other actions, SFAR 88 

requires certain type design (i.e., type 

certificate (TC) and supplemental type 

certificate (STC)) holders to substantiate 

that their fuel tank systems can prevent 

ignition sources in the fuel tanks. This 

requirement applies to type design 

holders for large turbine-powered 

transport airplanes and for subsequent 

modifications to those airplanes. It 

requires them to perform design reviews 

and to develop design changes and 

maintenance procedures if their designs 

do not meet the new fuel tank safety 

standards. As explained in the preamble 

to the rule, we intended to adopt 

airworthiness directives to mandate any 

changes found necessary to address 

unsafe conditions identified as a result 

of these reviews. 

In evaluating these design reviews, we 

have established four criteria intended 

to define the unsafe conditions 

associated with fuel tank systems that 

require corrective actions. The 

percentage of operating time during 

which fuel tanks are exposed to 

flammable conditions is one of these 

criteria. The other three criteria address 

the failure types under evaluation: 

single failures, single failures in 

combination with a latent condition(s), 

and in-service failure experience. For all 

four criteria, the evaluations included 

consideration of previous actions taken 

that may mitigate the need for further 

action. 

We have determined that the actions 

identified in this AD are necessary to 

reduce the potential of ignition sources 

inside fuel tanks, which, in combination 

with flammable fuel vapors, could result 

in fuel tank explosions and consequent 

loss of the airplane. 

Boeing has found that no separation 

was provided for the fuel quantity 

indication system (FQIS) wires. A 

potential hot short of the FQIS lead wire 

could cause the densitometer in the 

center fuel tank to overheat. In 

situations where the fuel level in the 

center fuel tank is low, the overheated 

densitometer could ignite flammable 

fuel vapors inside the center fuel tank. 

This condition, if not corrected, could 

result in a center fuel tank explosion 

and consequent loss of the airplane. 

Other Related Rulemaking 

On April 29, 2008, we issued AD 

2008–10–11, amendment 39–15517 (73 

FR 25974, May 8, 2008), applicable to 

all Boeing Model 757 airplanes. That 

AD requires revising the Airworthiness 

Limitations (AWLs) section of the 

Instructions for Continued 

Airworthiness (ICA) by incorporating 

new limitations for fuel tank systems to 

satisfy SFAR 88 requirements. That AD 

also requires the initial inspection of 

certain repetitive AWL inspections to 

phase in those inspections, and repair if 

necessary. That AD resulted from a 

design review of the fuel tank systems. 

We issued that AD to prevent the 

potential for ignition sources inside fuel 

tanks caused by latent failures, 

alterations, repairs, or maintenance 

actions, which, in combination with 

flammable fuel vapors, could result in a 

fuel tank explosion and consequent loss 

of the airplane. Incorporating AWL No. 

28–AWL–22 into the AWLs section of 

the ICA in accordance with paragraph 

(g)(3) of AD 2008–10–11 would 

terminate the action in paragraph (h) of 

this proposed AD. 

Relevant Service Information 

We have reviewed Boeing Alert 

Service Bulletin 757–28A0085, Revision 

2, dated December 11, 2007. The service 

bulletin describes the following 

procedures: 

• For certain airplanes: Measuring the 

electrical bonding resistance between 

the stiffeners located at inboard rear 

spar station (IRSS) 164.9 and IRSS 179.2 

and the rear spar web, and doing any 

applicable repair; installing the support 

brackets of the hot short protector (HSP) 

and the new support clamps of the wire 

bundles; installing the equipment of the 

HSP; and modifying the existing wire 

bundle and installing a new wire bundle 

(includes re-routing). 

• For certain other airplanes: 

Measuring the electrical bonding 

resistance between the stiffeners located 

at IRSS 164.9 and IRSS 179.2 and the 

rear spar web, measuring the electrical 

bonding resistance between the HSP 

and the rear spar web, and doing any 

applicable repair. 

We have also reviewed section 9, 

Revision November 2007, of the Boeing 

757 Maintenance Planning Data (MPD) 

Document, D622N001–9 (hereafter 

referred to as ‘‘the MPD’’). Subsection G 

‘‘AIRWORTHINESS LIMITATIONS—

FUEL SYSTEM AWLs’’ of the MPD 

describes AWLs for fuel tank systems 

and includes AWL No. 28–AWL–22, 

which is the critical design 

configuration control limitation to 

maintain the design features of the 

center fuel tank’s HSP during its 

replacement. 

FAA’s Determination and Requirements 

of This Proposed AD 

We are proposing this AD because we 

evaluated all relevant information and 

determined the unsafe condition 

described previously is likely to exist or 

develop in other products of the(se) 

same type design(s). This proposed AD 

would require accomplishing the 

actions specified in the service 

information described previously. 

Costs of Compliance 

We estimate that this proposed AD 

would affect 433 airplanes of U.S. 

registry. The following table provides 

the estimated costs for U.S. operators to 

comply with this proposed AD. 


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Federal Register / Vol. 73, No. 153 / Thursday, August 7, 2008 / Proposed Rules 45897 

ESTIMATED COSTS

Action Work 

hours 

Average 

labor rate 

per hour 

Parts 1 Cost per product 1

Number 

of U.S.- 

registered 

airplanes 

Fleet cost 1

Groups 1–3; measurement, installations, and 

modification.

8 $80 Between $14,110 and 

$14,215.

Between $14,750 and 

$14,855.

433 Between $6,386,750 and 

$6,432,215. 

Group 4; measurements 2 80 None .............................. $160 ............................... 433 $69,280. 

AWL Revision ................. 1 80 None .............................. $80 ................................. 433 $34,640. 

1 Depending on airplane configuration. 

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), 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. 

You can find our regulatory 

evaluation and the estimated costs of 

compliance in the AD Docket. 

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 FAA amends § 39.13 by adding 

the following new AD: 

Boeing: Docket No. FAA–2008–0846; 

Directorate Identifier 2008–NM–045–AD. 

Comments Due Date 

(a) We must receive comments by 

September 22, 2008. 

Affected ADs 

(b) None. 

Applicability 

(c) This AD applies to Boeing Model 757–

200, 757–200PF, and 757–300 series 

airplanes, certificated in any category; as 

identified in Boeing Alert Service Bulletin 

757–28A0085, Revision 2, dated December 

11, 2007. 

Note 1: This AD requires revisions to 

certain operator maintenance documents to 

include new inspections. Compliance with 

these inspections is required by 14 CFR 

91.403(c). For airplanes that have been 

previously modified, altered, or repaired in 

the areas addressed by these inspections, the 

operator may not be able to accomplish the 

inspections described in the revisions. In this 

situation, to comply with 14 CFR 91.403(c), 

the operator must request approval for an 

alternative method of compliance (AMOC) 

according to paragraph (l) of this AD. The 

request should include a description of 

changes to the required inspections that will 

ensure the continued operational safety of 

the airplane. 

Unsafe Condition 

(d) This AD results from fuel system 

reviews conducted by the manufacturer. We 

are issuing this AD to prevent the center fuel 

tank densitometer from overheating and 

becoming a potential ignition source inside 

the fuel tank, which, in combination with 

flammable fuel vapors, could result in a 

center fuel tank explosion and consequent 

loss of the airplane. 

Compliance 

(e) Comply with this AD within the 

compliance times specified, unless already 

done. 

Measurement, Installation, Modifications, 

Replacement, and Repair 

(f) For Groups 1 through 3 airplanes, as 

identified in Boeing Alert Service Bulletin 

757–28A0085, Revision 2, dated December 

11, 2007: Within 60 months after the effective 

date of this AD, do the measurement, 

installations, modifications, replacement, 

and applicable repair by accomplishing all 

the applicable actions specified in the 

Accomplishment Instructions of the service 

bulletin. Do the applicable repair before 

further flight. 

Measure and Repair 

(g) For Group 4 airplanes, as identified in 

Boeing Alert Service Bulletin 757–28A0085, 

Revision 2, dated December 11, 2007: Within 

60 months after the effective date of this AD, 

do the measurements and applicable repair 

by accomplishing all the applicable actions 

specified in the Accomplishment 

Instructions of the service bulletin. Do the 

applicable repair before further flight. 

Airworthiness Limitations (AWLs) Revision 

for AWL No. 28–AWL–22 

(h) Concurrently with accomplishing the 

actions required by paragraphs (f) and (g) of 

this AD, revise the AWLs section of the 

Instructions for Continued Airworthiness 

(ICA) by incorporating AWL No. 28–AWL–22 

of Subsection G of section 9, Revision 

November 2007, Boeing 757 Maintenance 

Planning Data (MPD) Document, D622N001–

9. 

No Alternative Critical Design Configuration 

Control Limitations (CDCCLs) 

(i) After accomplishing the action specified 

in paragraph (h) of this AD, no alternative 

CDCCLs may be used unless the CDCCLs are 

approved as an AMOC in accordance with 

the procedures specified in paragraph (k) of 

this AD. 

Credit for Actions Done According to 

Previous Issue of the Service Bulletin 

(j) Actions done before the effective date of 

this AD in accordance with Boeing Alert 

Service Bulletin 757–28A0085, Revision 1, 

dated April 16, 2007, are acceptable for 

compliance with the requirements of 

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


rmajette on PRODPC74 with PROPOSALS
45898 Federal Register / Vol. 73, No. 153 / Thursday, August 7, 2008 / Proposed Rules 

Terminating Action for AWLs Revision 

(k) Incorporating AWL No. 28–AWL–22 

into the AWLs section of the ICA in 

accordance with paragraph (g)(3) of AD 

2008–10–11, amendment 39–15517, 

terminates the action in paragraph (h) of this 

AD. 

Alternative Methods of Compliance 

(AMOCs) 

(l)(1) The Manager, Seattle ACO, FAA, 

ATTN: Jen Pei, Aerospace Engineer, Systems 

and Equipment Branch, ANM–130S, FAA, 

Seattle ACO, 1601 Lind Avenue, SW., 

Renton, Washington 98057–3356; telephone 

(425) 917–6409; 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. 

Issued in Renton, Washington, on July 29, 

2008. 

Ali Bahrami, 

Manager, Transport Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. E8–18222 Filed 8–6–08; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2008–0850; Directorate 

Identifier 2007–NM–342–AD] 

RIN 2120–AA64 

Airworthiness Directives; Fokker 

Model F.28 Mark 0100 Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Notice of proposed rulemaking 

(NPRM). 

SUMMARY: We propose to adopt a new 

airworthiness directive (AD) for the 

products listed above that would 

supersede an existing AD. This 

proposed 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 recent inspections it was found that 

some * * * bolts, that connect the horizontal 

stabilizer control unit actuator with the doglinks, were broken. This condition, if not 

corrected, could lead to [the loss of the flight 

control input connection to the horizontal 

stabilizer and consequent] partial loss of 

control of the aircraft. 

* * * * * 

The proposed AD would require actions 

that are intended to address the unsafe 

condition described in the MCAI. 

DATES: We must receive comments on 

this proposed AD by September 8, 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 

W12–40, 1200 New Jersey Avenue, SE., 

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

p.m., Monday through Friday, except 

Federal holidays. 

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: Tom 

Rodriguez, Aerospace Engineer, 

International Branch, ANM–116, FAA, 

Transport Airplane Directorate, 1601 

Lind Avenue, SW., Renton, WA 98057–

3356; telephone (425) 227–1137; 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–2008–0850; Directorate Identifier 

2007–NM–342–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 

On June 13, 1997, we issued AD 97–

13–05, Amendment 39–10051 (62 FR 

34617, June 27, 1997). That AD required 

actions intended to address an unsafe 

condition on the products listed above. 

Since we issued AD 97–13–05, we 

received reports of inspection results 

indicating that the bolt that connects the 

horizontal stabilizer control unit 

actuator with the dog-links was broken 

(one on the nut side, and one on the 

head side). When the bolts fails at the 

nut end, the remaining part of the bolt 

cannot drop out of the connection due 

to the limited amount of space available 

between the bolt head and plate, and the 

affected connection is still able to carry 

the system loads. However, if the head 

side of the bolt fails, then the bolt may 

drop out of the connection. 

The European Aviation Safety Agency 

(EASA), which is the Technical Agent 

for the Member States of the European 

Community, has issued EASA 

Airworthiness Directive 2007–0287, 

dated November 15, 2007 (referred to 

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

unsafe condition for the specified 

products. The MCAI states: 

In January 1996, Fokker issued Service 

Bulletin (SB) SBF–100–27–069 (referencing 

Menasco, now Goodrich, SB 23100–27–19) to 

introduce an inspection of bolt Part Number 

(P/N) 23233–1 for cracks after the 

examination of a failed bolt. This Service 

Bulletin was made mandatory by CAA–NL 

(Civil Aviation Authority—the Netherlands) 

with the issuance of AD BLA 1996–006 (A) 

[reference corresponding FAA AD 97–13–05]. 

Additionally the same SB introduced a lower 

torque value for these bolts. 

During recent inspections it was found that 

some of these bolts, that connect the 

horizontal stabilizer control unit actuator 

with the dog-links, were broken. This 

condition, if not corrected, could lead to [the 

loss of the flight control input connection to 

the horizontal stabilizer and consequent] 

partial loss of control of the aircraft. 

Since an unsafe condition has been 

identified that continues to exist or develop 

on other aircraft of the same type design, this 

Airworthiness Directive supersedes CAA–NL 

AD 1996–006 and requires an integrity check 

by a re-torque in accordance with SBF–100–

27–091 and the installation of a tie-wrap 

through the bolt, which will act as a retainer 

for the bolt and nut. The key function for this 

tie-wrap is to keep the bolt in place in the 

event the bolt head fails. 

The corrective action includes 

replacing any failed bolt (i.e., broken or 


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