38052 Federal Register / Vol. 75, No. 126 / Thursday, July 1, 2010 / Proposed Rules 

[FR Doc. 2010–14750 Filed 6–30–10; 8:45 am] 

BILLING CODE 6450–01–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2010–0452; Directorate 

Identifier 98–ANE–80–AD] 

RIN 2120–AA64 

Airworthiness Directives; Pratt & 

Whitney JT8D–209, –217, –217A, 

–217C, and –219 Series Turbofan 

Engines 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Notice of proposed rulemaking 

(NPRM). 

SUMMARY: The FAA proposes to 

supersede an existing airworthiness 

directive (AD) for Pratt & Whitney (PW) 

JT8D–209, –217, –217A, –217C, and 

–219 series turbofan engines. That AD 

requires initial and repetitive torque 

inspections of the 3rd stage and 4th 

stage low-pressure turbine (LPT) blades 

for shroud notch wear and replacement 

of the blade if wear limits are exceeded. 

That AD also requires replacing LPT-toexhaust case bolts and nuts with bolts 

and nuts made of Tinidur material. This 

proposed AD would require the same 

actions but would require replacement 

of the LPT-to-exhaust case bolts and 

nuts with longer bolts made of Tinidur 

material, with nuts made of Tinidur 

material, and installation of crushable 

sleeve spacers on the bolts. This 

proposed AD results from nine reports 

of failure of Tinidur material LPT-toexhaust case bolts since AD 2005–02–03 

became effective. We are proposing this 

AD to prevent turbine blade failures that 

could result in uncontained engine 

debris and damage to the airplane. 

DATES: We must receive any comments 

on this proposed AD by August 30, 

2010. 

ADDRESSES: Use one of the following 

addresses to comment on this proposed 

AD. 

• Federal eRulemaking Portal: Go to 

http://www.regulations.gov and follow 

the instructions for sending your 

comments electronically. 

• Mail: Docket Management Facility, 

U.S. Department of Transportation, 1200 

New Jersey Avenue, SE., West Building 

Ground Floor, Room W12–140, 

Washington, DC 20590–0001. 

• Hand Delivery: Deliver to Mail 

address above between 9 a.m. and 5 

p.m., Monday through Friday, except 

Federal holidays. 

• Fax: (202) 493–2251. 

FOR FURTHER INFORMATION CONTACT: 

Kevin Dickert, Aerospace Engineer, 

Engine Certification Office, FAA, Engine 

& Propeller Directorate, 12 New England 

Executive Park, Burlington, MA 01803; 

e-mail: kevin.dickert@faa.gov; telephone 

(781) 238–7117; fax (781) 238–7199. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

We invite you to send any written 

relevant data, views, or arguments 

regarding this proposal. Send your 

comments to an address listed under 

ADDRESSES. Include ‘‘Docket No. FAA– 

2010–0452; Directorate Identifier 98– 

ANE–80–AD’’ in the subject line of your 

comments. We specifically invite 

comments on the overall regulatory, 

economic, environmental, and energy 

aspects of the proposed AD. We will 

consider all comments received by the 

closing date and may amend the 

proposed AD in light 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 with FAA 

personnel concerning this proposed AD. 

Using the search function of the Web 

site, anyone can find and read the 

comments in any of our dockets, 

including, if provided, the name of the 

individual who sent the comment (or 

signed the comment on behalf of an 

association, business, labor union, etc.). 

You may review the DOT’s complete 

Privacy Act Statement in the Federal 

Register published on April 11, 2000 

(65 FR 19477–78). 

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 the 

same as the Mail address provided in 

the ADDRESSES section. Comments will 

be available in the AD docket shortly 

after receipt. 

Discussion 

The FAA proposes to amend 14 CFR 

part 39 by superseding AD 2005–02–03, 

Amendment 39–13948 (70 FR 3867, 

January 27, 2005). That AD requires 

torque inspection of the 3rd stage and 

4th stage LPT blades for shroud notch 

wear and replacement of the blade if 

wear limits are exceeded. That AD also 

requires replacing LPT-to-exhaust case 

bolts and nuts with bolts and nuts made 

of Tinidur material. That AD was the 

result of reports of 194 blade fractures 

since 1991, with 37 of those blade 

fractures resulting in LPT case 

separation, and three reports of 

uncontained 3rd stage and 4th stage LPT 

blade failures with cowl penetration. 

That condition, if not corrected, could 

result in turbine blade failures that 

could result in uncontained engine 

debris and damage to the airplane. 

Actions Since AD 2005–02–03 Was 

Issued 

Since AD 2005–02–03 was issued, we 

received nine reports of failure of 

Tinidur material LPT-to-exhaust case 

bolts occurring during 3rd and/or 4th 

stage blade fracture events. Three of 

these events resulted in cowl 

penetration. The bolts mandated by AD 

2005–02–03 do not provide enough 

energy absorption during a blade 

fracture event. PW has introduced 

longer bolts made of Tinidur and 

crushable sleeve spacers that will 

increase the energy absorption 

capability of the fasteners during a blade 

fracture event. 

Also since AD 2005–02–03 was 

issued, PW revised Alert Service 

Bulletin (ASB) No. JT8D A6224, 

Revision 5, dated June 11, 2004, with 

Revision 6, dated May 3, 2007. 

Relevant Service Information 

We have reviewed and approved the 

technical contents of PW ASB No. JT8D 

A6224, Revision 6, dated May 3, 2007. 

That ASB describes procedures for 

performing torque inspections of the 3rd 

and 4th stage turbine blades. 

FAA’s Determination and Requirements 

of the Proposed AD 

We have evaluated all pertinent 

information and identified an unsafe 

condition that is likely to exist or 

develop on other products of this same 

type design. For that reason, we are 

proposing this AD, which would require 

torque inspection of the 3rd stage and 

4th stage LPT blades for shroud notch 

wear and replacement of the blade if 

wear limits are exceeded. This proposed 

AD would also require the replacement 

of LPT-to-exhaust case bolts and nuts 

with longer bolts made of Tinidur 

material, with nuts made of Tinidur 

material, and installation of crushable 

sleeve spacers on the bolts. 

WReier-Aviles on DSKGBLS3C1PROD with PROPOSALS

Federal Register / Vol. 75, No. 126 / Thursday, July 1, 2010 / Proposed Rules 38053 

Costs of Compliance 

We estimate that this proposed AD 

would affect 1,143 engines installed on 

airplanes of U.S. registry. We also 

estimate that it would take about 1 

work-hour per engine to perform the 

proposed blade inspection, and 1.5 

work-hours per engine to replace the 

LPT-to-exhaust case bolts and nuts and 

install the crushable sleeve spacers. 

Required bolts, nuts, and sleeve spacers 

would cost about $4,576 per engine. We 

anticipate that 61 engines would require 

blade replacement each year. Required 

blades would cost about $131,560 per 

engine. The average labor rate is $85 per 

work-hour. Based on these figures, we 

estimate the total cost of the proposed 

AD to U.S. operators to be $13,617,671. 

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 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. Would 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. 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, Incorporation by reference, 

Safety. 

The Proposed Amendment 

Under the authority delegated to me 

by the Administrator, the Federal 

Aviation Administration 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 

removing Amendment 39–13948 (70 FR 

3867, January 27, 2005) and by adding 

a new airworthiness directive to read as 

follows: 

Pratt & Whitney: Docket No. FAA–2010– 

0452; Directorate Identifier 98–ANE–80– 

AD. 

Comments Due Date 

(a) The Federal Aviation Administration 

(FAA) must receive comments on this 

airworthiness directive (AD) action by 

August 30, 2010. 

Affected ADs 

(b) This AD supersedes AD 2005–02–03. 

Applicability 

(c) This AD applies to Pratt & Whitney 

(PW) JT8D–209, –217, –217A, –217C, and 

–219 series turbofan engines. These engines 

are installed on, but not limited to, Boeing 

727 series and McDonnell Douglas MD–80 

series airplanes. 

Unsafe Condition 

(d) This AD results from nine reports of 

failure of Tinidur material low-pressure 

turbine (LPT)-to-exhaust case bolts since AD 

2005–02–03 became effective. We are issuing 

this AD to prevent turbine blade failures that 

could result in uncontained engine debris 

and damage to 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 2005–02–03 

Initial Torque Inspection for JT8D–209, 

–217, and –217A Engines 

(f) For JT8D–209, –217, and –217A engines, 

perform the initial torque inspection of 3rd 

and 4th stage LPT blades for shroud notch 

wear. Use the procedures described in 

Accomplishment Instructions, Part 1, 

Paragraphs 1 through 3, of PW Alert Service 

Bulletin (ASB) No. JT8D A6224, Revision 6, 

dated May 3, 2007, at the applicable 

threshold in the following Table 1: 

TABLE 1—INITIAL TORQUE INSPECTION THRESHOLD FOR JT8D–209, –217, AND –217A ENGINES

Blade type 

Hours time-in-service (TIS) 

as of March 3, 2005 (the 

effective 

date of 

AD 2005–02–03) 

Inspection threshold 

(1) New pre-Service Bulletin (SB) No. 5867 (small notch) 

3rd stage turbine blades.

Any number ........................ Within 6,000 hours TIS. 

(2) Refurbished pre-SB No. 5867 (small notch) 3rd stage 

turbine blades.

(i) Fewer than 3,000 ........... Within 4,000 hours TIS. 

(ii) 3,000 or more ................ Within 6,000 hours TIS, or within 1,000 hours TIS from 

March 3, 2005, whichever occurs first. 

(3) New post-SB No. 5867 (large notch) 3rd stage turbine blades.Any number ........................ Within 10,000 hours TIS. 

(4) Refurbished post-SB No. 5867 (large notch) 3rd 

stage turbine blades.

(i) Fewer than 6,000 ........... Within 7,000 hours TIS. 

(ii) 6,000 or more ................ Within 8,000 hours TIS, or within 1,000 hours TIS from 

March 3, 2005, whichever occurs first. 

(5) New pre-SB No. 6029 (small notch) 4th stage turbine 

blades.

Any number ........................ Within 6,000 hours TIS. 

WReier-Aviles on DSKGBLS3C1PROD with PROPOSALS

38054 Federal Register / Vol. 75, No. 126 / Thursday, July 1, 2010 / Proposed Rules 

TABLE 1—INITIAL TORQUE INSPECTION THRESHOLD FOR JT8D–209, –217, AND –217A ENGINES—Continued 

Blade type 

Hours time-in-service (TIS) 

as of March 3, 2005 (the 

effective 

date of 

AD 2005–02–03) 

Inspection threshold 

(6) Refurbished pre-SB No. 6029 (small notch) 4th stage 

turbine blades.

(i) Fewer than 3,000 ........... Within 4,000 hours TIS. 

(ii) 3,000 or more ................ Within 6,000 hours TIS, or within 1,000 hours TIS from 

March 3, 2005, whichever occurs first. 

(7) New post-SB No. 6029 or new post-SB No. 6308 

(large notch) 4th stage turbine blades.

Any number ........................ Within 10,000 hours TIS. 

(8) Refurbished post-SB No. 6029 or refurbished postSB No. 6308 (large notch) 4th stage turbine blades.(i) Fewer than 6,000 ........... Within 7,000 hours TIS. 

(ii) 6,000 or more ................ Within 8,000 hours TIS, or within 1,000 hours TIS from 

March 3, 2005, whichever occurs first. 

Repetitive Torque Inspections for JT8D–209, 

–217, and –217A Engines 

(g) For JT8D–209, –217, and –217A 

engines, perform repetitive torque 

inspections of 3rd and 4th stage LPT blades 

for shroud notch wear. Use the procedures 

described in Accomplishment Instructions, 

Part 1, Paragraph 1 of PW ASB No. JT8D 

A6224, Revision 6, dated May 3, 2007, at the 

applicable intervals in the following Table 2 

and Table 3: 

TABLE 2—3RD STAGE REPETITIVE TORQUE INSPECTION INTERVALS FOR JT8D–209, –217, AND –217A ENGINES

Inspection torque readings Number of 

readings Disposition 

Greater than or equal to 15 LB–IN (1.695 N.m) .............. All ....................................... Repeat torque inspection within 1,000 hours TIS since 

last inspection. 

Less than 15 LB–IN (1.695 N.m) but greater than or 

equal to 10 LB–IN (1.130 N.m).

One or more ....................... Repeat torque inspection within 500 hours TIS since 

last inspection. 

Less than 10 LB–IN (1.130 N.m) but greater than or 

equal to 5 LB–IN (0.565 N.m).

One to three ....................... Repeat torque inspection within 125 hours TIS since 

last inspection. 

Less than 10 LB–IN (1.130 N.m) but greater than or 

equal to 5 LB–IN (0.565 N.m).

Four or more ...................... Remove engine from service within 20 hours TIS since 

last inspection. 

Less than 5 LB–IN (0.565 N.m) ....................................... One or more ....................... Remove engine from service within 20 hours TIS since 

last inspection. 

TABLE 3—4TH STAGE REPETITIVE TORQUE INSPECTION INTERVALS FOR JT8D–209, –217, AND –217A ENGINES

Inspection torque readings Number of 

readings Disposition 

Greater than or equal to 15 LB–IN (1.695 N.m) .............. All ....................................... Repeat torque inspection within 1,000 hours TIS since 

last inspection. 

Less than 15 LB–IN (1.695 N.m) but greater than or 

equal to 10 LB–IN (1.130 N.m).

One or more ....................... Repeat torque inspection within 500 hours TIS since 

last inspection. 

Less than 10 LB–IN (1.130 N.m) but greater than or 

equal to 5 LB–IN (0.565 N.m).

One to six ........................... Repeat torque inspection within 125 hours TIS since 

last inspection. 

Less than 10 LB–IN (1.130 N.m) but greater than or 

equal to 5 LB–IN (0.565 N.m).

Seven or more ................... Remove engine from service within 20 hours TIS since 

last inspection. 

Less than 5 LB–IN (0.565 N.m) ....................................... One or more ....................... Remove engine from service within 20 hours TIS since 

last inspection. 

(h) Subsequent repeat inspection intervals 

must not exceed the previous inspection 

interval. 

JT8D–209, –217, and –217A Engines 

Removed From Service 

(i) JT8D–209, –217, and –217A engines 

removed from service may be returned to 

service after a detailed inspection and repair 

or replacement for all blades, of the failed 

stage, that exceed Engine Manual limits is 

done. Information on repairing or replacing 

turbine blades can be found in Sections 72– 

53–12 through 72–53–13 of the JT8D–200 

Engine Manual, Part No. 773128. 

Initial Inspection for JT8D–217C and –219 

Engines 

(j) For JT8D–217C and –219 engines, 

perform the initial torque inspection of 4th 

stage LPT blades for shroud notch wear. Use 

the procedures described in Accomplishment 

Instructions, Part 2, Paragraphs 1 through 3 

of PW ASB No. JT8D A6224, Revision 6 

dated May 3, 2007, at the applicable 

threshold in the following Table 4: 

WReier-Aviles on DSKGBLS3C1PROD with PROPOSALS

Federal Register / Vol. 75, No. 126 / Thursday, July 1, 2010 / Proposed Rules 38055 

TABLE 4—INITIAL TORQUE INSPECTION THRESHOLD FOR JT8D–217C AND –219 ENGINES

Blade type TIS as of March 3, 2005 Inspection threshold 

(1) New pre-SB No. 6090 (small notch) 4th stage turbine 

blades.

Any number ........................ Within 5,000 hours TIS. 

(2) Refurbished pre-SB No. 6090 (small notch) 4th stage 

turbine blades.

(i) Fewer than 3,000 ........... Within 4,000 hours TIS. 

(ii) 3,000 or more ................ Within 5,000 hours TIS, or within 1,000 hours TIS from 

March 3, 2005, whichever occurs first. 

(3) New post-SB No. 6090, new post-SB No. 6402, or 

new post-SB No. 6412 (large notch) 4th stage turbine 

blades.

Any number ........................ Within 10,000 hours TIS. 

(4) Refurbished ‘‘As-Cast’’ post-SB No. 6090, post-SB 

No. 6402, or post-SB No. 6412 (large notch) 4th stage 

turbine blades.

Any number ........................ Within 7,000 hours TIS. 

(5) Refurbished ‘‘Modified’’ post-SB No. 6090, post-SB 

No. 6402, or post-SB No. 6412 (large notch) 4th stage 

turbine blades.

(i) Fewer than 3,000 ........... Within 4,000 hours TIS. 

(ii) 3,000 or more ................ Within 7,000 hours TIS, or within 1,000 hours TIS from 

March 3, 2005, whichever occurs first. 

Repetitive Torque Inspections for JT8D–217C 

and –219 Engines 

(k) For JT8D–217C and –219 engines, 

perform repetitive torque inspections of 4th 

stage LPT blades for shroud notch wear. Use 

the procedures described in Accomplishment 

Instructions, Part 2, Paragraph 1 of PW ASB 

No. JT8D A6224, Revision 6, dated May 3, 

2007, at the applicable intervals in the 

following Table 5: 

TABLE 5—REPETITIVE TORQUE INSPECTION INTERVALS FOR JT8D–217C AND –219 ENGINES

Inspection torque readings Number of readings Disposition 

Greater than or equal to 15 LB–IN (1.695 N.m) .............. All ....................................... Repeat torque inspection within 1,000 hours TIS since 

last inspection. 

Less than 15 LB–IN (1.695 N.m) but greater than or 

equal to 10 LB–IN (1.130 N.m).

One or more ....................... Repeat torque inspection within 500 hours TIS since 

last inspection. 

Less than 10 LB–IN (1.130 N.m) but greater than or 

equal to 5 LB–IN (0.565 N.m).

One to six ........................... Repeat torque inspection within 125 hours TIS since 

last inspection. 

Less than 10 LB–IN (1.130 N.m) but greater than or 

equal to 5 LB–IN (0.565 N.m).

Seven or more ................... Remove engine from service within 20 hours TIS since 

last inspection. 

Less than 5 LB–IN (0.565 N.m) ....................................... One or more ....................... Remove engine from service within 20 hours TIS since 

last inspection. 

(l) Subsequent repeat inspection intervals 

must not exceed the previous inspection 

interval. 

JT8D–217C and –219 Engines Removed From 

Service 

(m) JT8D–217C and –219 engines removed 

from service may be returned to service after 

a detailed inspection and repair or 

replacement for all blades, of the failed stage, 

that exceed Engine Manual limits is done. 

Information on repairing or replacing turbine 

blades can be found in Sections 72–53–12 

through 72–53–13 of the JT8D–200 Engine 

Manual, Part No. 773128. 

Other Criteria for All Engine Models Listed 

in This AD 

(n) Whenever a refurbished or used blade 

is intermixed with new blades in a rotor, use 

the lowest initial inspection threshold that is 

applicable. 

(o) The initial torque inspection or the 

repetitive inspection intervals for a particular 

stage may not be reset unless the blades for 

that stage are refurbished or replaced. 

(p) Whenever a used (service run) blade is 

reinstalled in a rotor, the previous used time 

should be subtracted from the initial torque 

inspection threshold. 

What This AD Changes 

LPT-to-Exhaust Case Bolts and Nuts 

Replacement, and Crushable Sleeve Spacer 

Installation 

(q) At next accessibility to the LPT-toExhaust Case bolts and nuts, do the 

following: 

(1) Replace the bolts with part number (P/ 

N) MS9557–26 bolts; and 

(2) Replace the nuts with P/N 375095 nuts 

or P/N 490270 nuts; and 

(3) Install crushable sleeve spacers, P/N 

822903, under the head of the bolts. 

(4) Guidance on replacing the bolts and 

nuts and installing the crushable sleeve 

spacers can be found in PW ASB No. JT8D 

A6494, Revision 1, dated January 26, 2010. 

Previous Credit 

(r) Initial inspections performed before the 

effective date of this AD using PW ASB No. 

JT8D A6224, Revision 5, dated June 11, 2004, 

or Revision 6, dated May 3, 2007, satisfy the 

initial inspection requirements of this AD. 

Definitions 

(s) For the purpose of this AD, 

refurbishment is defined as restoration of 

either the shrouds or blade retwist or both, 

per the JT8D–200 Engine Manual, Part No. 

773128. 

(t) For the purpose of this AD, ‘‘As-Cast’’ 

refers to blades that were machined from new 

castings and ‘‘Modified’’ refers to blades that 

were derived from the pre-SB No. 6090 

configuration. 

(u) For the purpose of this AD, 

‘‘accessibility to the LPT-to-exhaust case 

bolts’’ refers to when the engine is 

disassembled sufficiently to give access to 

the LPT-to-exhaust case bolts, which is 

whenever the inner turbine fan ducts are 

removed. 

Alternative Methods of Compliance 

(v) The Manager, Engine Certification 

Office, has the authority to approve 

alternative methods of compliance (AMOCs) 

for this AD if requested using the procedures 

found in 14 CFR 39.19. AMOCs approved for 

the initial and repetitive inspection 

requirements of AD 2005–02–03 are 

approved as AMOCs for this AD. 

Related Information 

(w) Contact Kevin Dickert, Aerospace 

Engineer, Engine Certification Office, FAA, 

Engine & Propeller Directorate, 12 New 

England Executive Park, Burlington, MA 

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38056 Federal Register / Vol. 75, No. 126 / Thursday, July 1, 2010 / Proposed Rules 

01803; e-mail: kevin.dickert@faa.gov; 

telephone (781) 238–7117; fax (781) 238– 

7199, for more information about this AD. 

(x) Contact Pratt & Whitney, 400 Main St., 

East Hartford, CT 06108; telephone (860) 

565–8770, fax (860) 565–4503, for a copy of 

the service information referenced in this 

AD. 

Issued in Burlington, Massachusetts, on 

June 22, 2010. 

Peter A. White, 

Assistant Manager, Engine and Propeller 

Directorate, Aircraft Certification Service. 

[FR Doc. 2010–16010 Filed 6–30–10; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2010–0645; Directorate 

Identifier 2009–NM–200–AD] 

RIN 2120–AA64 

Airworthiness Directives; McDonnell 

Douglas Corporation Model MD–90–30 

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 

Model MD–90–30 airplanes. The 

existing AD currently requires a detailed 

inspection for certain defects of the 

upper fasteners of the aft mount support 

fittings of the left and right engines, and 

corrective actions if necessary. This 

proposed AD would instead require 

repetitive replacement of the upper row 

of fasteners of the support fittings of the 

engine aft mount with new fasteners; 

and perform repetitive general visual 

inspections for defects of the lower row 

fasteners (Row B) of the support fittings 

of the left and right engine aft mounts, 

and replacement of all clearance fit 

fasteners in the lower row if necessary. 

This proposed AD results from reports 

of loose, cracked, or missing fasteners in 

the aft mount support fitting of the left 

and right engines. We are proposing this 

AD to prevent loose, cracked, or missing 

fasteners in the engine aft mount 

support fittings, which could lead to 

separation of the support fittings from 

the pylon, and could result in 

separation of the engine from the 

airplane. 

DATES: We must receive comments on 

this proposed AD by August 16, 2010. 

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 proposed AD, contact Boeing 

Commercial Airplanes, Attention: Data 

& Services Management, 3855 

Lakewood Boulevard, MC D800 0019, 

Long Beach, California 90846–0001; 

telephone 206–544–5000, extension 2; 

fax 206 766–5683; e-mail 

dse.boecom@boeing.com; Internet 

https://www.myboeingfleet.com. You 

may review copies of the referenced 

service information at the FAA, 

Transport Airplane Directorate, 1601 

Lind Avenue, SW., Renton, Washington. 

For information on the availability of 

this material at the FAA, call 425–227– 

1221. 

Examining the AD Docket 

You may examine the AD docket on 

the Internet at http:// 

www.regulations.gov; or in person at the 

Docket Management Facility between 9 

a.m. and 5 p.m., Monday through 

Friday, except Federal holidays. The AD 

docket contains this proposed AD, the 

regulatory evaluation, any comments 

received, and other information. The 

street address for the Docket Office 

(telephone 800–647–5527) is in the 

ADDRESSES section. Comments will be 

available in the AD docket shortly after 

receipt. 

FOR FURTHER INFORMATION CONTACT: 

Roger Durbin, Aerospace Engineer, 

Airframe Branch, ANM–120L, FAA, Los 

Angeles Aircraft Certification Office, 

3960 Paramount Boulevard, Lakewood, 

California 90712–4137; telephone (562) 

627–5233; fax (562) 627–5210. 

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–2010–0645; Directorate Identifier 

2009–NM–200–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 August 25, 2008, we issued AD 

2008–18–10, Amendment 39–15667 (73 

FR 52203, September 9, 2008), for 

certain McDonnell Douglas Corporation 

Model MD–90–30 airplanes. That AD 

requires a detailed inspection for certain 

defects of the upper fasteners of the aft 

mount support fittings of the left and 

right engines, and corrective actions if 

necessary. That AD resulted from 

reports of loose, cracked, or missing 

fasteners in the aft mount support 

fittings of the left and right engines. We 

issued that AD to detect and correct 

loose, cracked, or missing fasteners in 

the engine aft support mount fittings, 

which could lead to separation of the 

support fittings from the pylon, and 

could result in separation of the engine 

from the airplane. 

Actions Since Existing AD Was Issued 

The preamble to AD 2008–18–10 

explains that we considered the 

requirements ‘‘interim action’’ and were 

considering further rulemaking. We now 

have determined that further 

rulemaking is indeed necessary, and 

this proposed AD follows from that 

determination. 

We also have received additional 

reports of loose, cracked, or missing 

fasteners in the aft mount support fitting 

of the left and right engines on 29 

McDonnell Douglas Corporation Model 

MD–90–30 airplanes. The airplanes had 

accumulated between 15,560 and 37,298 

total flight hours, and between 13,995 

and 31,294 total flight cycles. 

Results of a safety assessment of the 

missing fasteners indicate that loose or 

otherwise discrepant fasteners in the top 

horizontal row, common with the pylon 

skin, significantly decrease the margin 

of safety of the aft mount support 

installation at the design limit load. 

Replacement of the upper row of 

fasteners at new specified intervals will 

help minimize the possibility of these 

fasteners becoming an unsafe condition 

while in service. Inspection of the lower 

WReier-Aviles on DSKGBLS3C1PROD with PROPOSALS