Federal Register / Vol. 75, No. 190 / Friday, October 1, 2010 / Proposed Rules 60665 

Maintenance Program Revision 

(h) Concurrently with accomplishing the 

actions required by paragraph (g) of this AD, 

revise the maintenance program by 

incorporating Airworthiness Limitation 

(AWL) No. 28–AWL–22 of Section D of the 

Boeing 747–100/200/300/SP Airworthiness 

Limitations (AWLs) and Certification 

Maintenance Requirements (CMRs), D6– 

13747–CMR, Revision March 2008. Where 

the AWL states ‘‘28–31–00,’’ the correct 

section number is ‘‘28–42–00.’’ 

Airplane Flight Manual (AFM) Revision 

(i) Concurrently with accomplishing the 

actions required by paragraph (g) of this AD, 

revise Section 1, ‘‘Certificate Limitations,’’ of 

the applicable Boeing 747 AFM to include 

the following statement. This may be done by 

inserting a copy of this AD into the AFM. 

‘‘When the center tank override jettison 

pumps are selected off, the amber pump low 

pressure lights on the Flight Engineer’s panel 

should illuminate and remain on. If a pump 

low pressure light on the Flight Engineer’s 

panel does not illuminate, open the 

associated pump circuit breaker.’’ 

Note 3: When a statement identical to that 

in paragraph (i) of this AD has been included 

in the general revisions of the AFM, the 

general revisions may be inserted into the 

AFM, and the copy of this AD may be 

removed from the AFM. 

No Alternative Inspections or Inspection 

Intervals 

(j) After accomplishing the action specified 

in paragraph (h) of this AD, no alternative 

inspections or inspection intervals may be 

used unless the inspections or inspection 

intervals are approved as an AMOC in 

accordance with the procedures specified in 

paragraph (l) of this AD. 

Terminating Action for Maintenance 

Program Revision 

(k) Incorporating AWL No. 28–AWL–22 

into the maintenance program in accordance 

with paragraph (g) of AD 2008–10–07, 

Amendment 39–15513, or AD 2008–10–07 

R1, Amendment 39–16070, terminates the 

action required by paragraph (h) of this AD. 

Alternative Methods of Compliance 

(AMOCs) 

(l)(1) The Manager, Seattle Aircraft 

Certification Office (ACO), FAA, has the 

authority to approve AMOCs for this AD, if 

requested using the procedures found in 14 

CFR 39.19. Send information to ATTN: 

Douglas Bryant, Aerospace Engineer, 

Propulsion Branch, ANM–140S, FAA, Seattle 

ACO, 1601 Lind Avenue, SW., Renton, 

Washington 98057–3356; telephone (425) 

917–6505; fax (425) 917–6590. Information 

may be e-mailed to: 9-ANM-Seattle-ACOAMOC-Requests@faa.gov. 

(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 principal maintenance inspector 

(PMI) or principal avionics inspector (PAI), 

as appropriate, or lacking a principal 

inspector, your local Flight Standards District 

Office. The AMOC approval letter must 

specifically reference this AD. 

Issued in Renton, Washington, on 

September 20, 2010. 

Ali Bahrami, 

Manager, Transport Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. 2010–24717 Filed 9–30–10; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2010–0953; Directorate 

Identifier 2010–NM–010–AD] 

RIN 2120–AA64 

Airworthiness Directives; McDonnell 

Douglas Corporation Model MD–90–30 

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 

Model MD–90–30 airplanes. This 

proposed AD would require repetitive 

high frequency eddy current inspections 

for cracking on the hinge bearing lugs of 

the left and right sides of the center 

section ribs of the horizontal stabilizer, 

and related investigative and corrective 

actions if necessary. This proposed AD 

results from reports of cracks found on 

either the left or right (or in one case, 

both) sides of the center section ribs of 

the horizontal stabilizer. We are 

proposing this AD to detect and correct 

cracking in the hinge bearing lugs of the 

center section of the left and right ribs, 

which could result in failure of the 

hinge bearing lugs and consequent 

inability of the horizontal stabilizer to 

sustain the required loads. 

DATES: We must receive comments on 

this proposed AD by November 15, 

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 

(ACO), 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–2010–0953; Directorate Identifier 

2010–NM–010–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. 


jlentini on DSKJ8SOYB1PROD with PROPOSALS
60666 Federal Register / Vol. 75, No. 190 / Friday, October 1, 2010 / Proposed Rules 

Discussion 

We have received seven reports of 

cracks found on either the left or right 

(or in one case, both) sides of the center 

section ribs of the horizontal stabilizer. 

These cracks were located on the aft 

face of the hinge bearing lugs on the 

horizontal stabilizer. Cracks were 

reported on MD–90 airplanes that had 

accumulated 9,051 to 21,183 total flight 

hours, and 8,939 to 20,893 total flight 

cycles. The cause of the cracking has not 

been determined. Undetected cracking 

in the hinge bearing lugs of the center 

section of the left and right ribs, if not 

corrected, could result in failure of the 

hinge bearing lugs and consequent 

inability of the horizontal stabilizer to 

sustain the required loads. 

Relevant Service Information 

We have reviewed Boeing Alert 

Service Bulletin MD90–55A016, 

Revision 1, dated February 17, 2010. 

Boeing Alert Service Bulletin MD90– 

55A016, Revision 1, dated February 17, 

2010, describes procedures for doing 

repetitive high frequency eddy current 

(HFEC) inspections for cracking on the 

hinge bearing lugs on the aft face of the 

horizontal stabilizer center section on 

the left and right ribs, and doing 

applicable related investigative and 

corrective actions. The related 

investigative action is measuring the 

crack length. The corrective actions 

include blending out cracks and 

replacing the rib of the center section of 

the horizontal stabilizer. For airplanes 

on which a blend out is done, Boeing 

Alert Service Bulletin MD90–55A016, 

Revision 1, dated February 17, 2010, 

describes procedures for doing 

repetitive HFEC inspections for cracking 

of the blend out. For airplanes on which 

the replacement is done, Boeing Alert 

Service Bulletin MD90–55A016, 

Revision 1, dated February 17, 2010, 

describes procedures for doing 

repetitive HFEC inspections for cracking 

of the replaced horizontal stabilizer rib. 

For the initial HFEC inspection, 

Boeing Alert Service Bulletin MD90– 

55A016, Revision 1, dated February 17, 

2010, specifies a compliance time of 

before the accumulation of 7,200 total 

flight cycles or within 1,505 flight 

cycles after the original issue date of 

Boeing Alert Service Bulletin MD90– 

55A016, Revision 1, dated February 17, 

2010, whichever occurs later. 

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 same 

type design. This proposed AD would 

require accomplishing the actions 

specified in the service information 

described previously, except as 

discussed under ‘‘Differences Between 

the Proposed AD and Service Bulletin.’’ 

Differences Between the Proposed AD 

and Service Bulletin 

For Condition 2A specified in Boeing 

Alert Service Bulletin MD90–55A016, 

Revision 1, dated February 17, 2010, the 

service bulletin specifies doing 

repetitive inspections of the blend out 

but did not identify corrective actions 

when cracks are found during those 

inspections. This proposed AD would 

require replacing the horizontal 

stabilizer center section rib when cracks 

are found during inspections of the 

blend out. We have coordinated this 

difference with Boeing. 

For Condition 2B specified in Boeing 

Alert Service Bulletin MD90–55A016, 

Revision 1, dated February 17, 2010, the 

service bulletin specifies doing 

repetitive inspections of the replaced 

horizontal stabilizer center section rib at 

intervals not to exceed 1,680 flight 

cycles. This proposed AD would require 

doing an inspection of the replaced 

horizontal stabilizer center section rib 

and all applicable corrective actions and 

repetitive inspections (for Condition 1, 

the repetitive interval is 1,680 flight 

cycles; for Condition 2A, the repetitive 

interval is 400 flight cycles). 

Interim Action 

We consider this proposed AD 

interim action. The manufacturer is 

currently developing a modification that 

will address the unsafe condition 

identified in this AD. Once this 

modification is developed, approved, 

and available, we might consider 

additional rulemaking. 

Costs of Compliance 

We estimate that this proposed AD 

would affect 16 airplanes of U.S. 

registry. We also estimate that it would 

take about 2 work-hours per product to 

comply with this proposed AD. The 

average labor rate is $85 per work-hour. 

Based on these figures, we estimate the 

cost of this proposed AD to the U.S. 

operators to be $2,720, or $170 per 

product. 

Authority for This Rulemaking 

Title 49 of the United States Code 

specifies the FAA’s authority to issue 

rules on aviation safety. Subtitle I, 

section 106, describes the authority of 

the FAA Administrator. ‘‘Subtitle VII: 

Aviation Programs,’’ describes in more 

detail the scope of the Agency’s 

authority. 

We are issuing this rulemaking under 

the authority described in ‘‘Subtitle VII, 

Part A, Subpart III, Section 44701: 

General requirements.’’ Under that 

section, Congress charges the FAA with 

promoting safe flight of civil aircraft in 

air commerce by prescribing regulations 

for practices, methods, and procedures 

the Administrator finds necessary for 

safety in air commerce. This regulation 

is within the scope of that authority 

because it addresses an unsafe condition 

that is likely to exist or develop on 

products identified in this rulemaking 

action. 

Regulatory Findings 

We determined that this 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, Incorporation by reference, 

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: 

McDonnell Douglas Corporation: Docket No. 

FAA–2010–0953; Directorate Identifier 

2010–NM–010–AD. 


jlentini on DSKJ8SOYB1PROD with PROPOSALS
Federal Register / Vol. 75, No. 190 / Friday, October 1, 2010 / Proposed Rules 60667 

Comments Due Date 

(a) We must receive comments by 

November 15, 2010. 

Affected ADs 

(b) None. 

Applicability 

(c) This AD applies to all McDonnell 

Douglas Corporation Model MD–90–30 

airplanes, certificated in any category. 

Subject 

(d) Air Transport Association (ATA) of 

America Code 55: Stabilizers. 

Unsafe Condition 

(e) This AD results from reports of cracks 

found on either the left or right (or in one 

case, both) sides of the center section ribs of 

the horizontal stabilizer. The Federal 

Aviation Administration is issuing this AD to 

detect and correct cracking in the hinge 

bearing lugs of the center section of the left 

and right ribs, which could result in failure 

of the hinge bearing lugs and consequent 

inability of the horizontal stabilizer to sustain 

the required loads. 

Compliance 

(f) You are responsible for having the 

actions required by this AD performed within 

the compliance times specified, unless the 

actions have already been done. 

Repetitive Inspections and Corrective 

Actions for Cracking 

(g) At the applicable time in paragraph 

1.E., ‘‘Compliance,’’ of Boeing Alert Service 

Bulletin MD90–55A016, Revision 1, dated 

February 17, 2010, except as required by 

paragraph (n) of this AD, do a high frequency 

eddy current (HFEC) inspection for cracking 

on the hinge bearing lugs of the left and right 

sides of the center section ribs of the 

horizontal stabilizer, and do all applicable 

related investigative actions, in accordance 

with the Accomplishment Instructions of 

Boeing Alert Service Bulletin MD90–55A016, 

Revision 1, dated February 17, 2010. Do all 

applicable related investigative actions before 

further flight. 

(h) If during any inspection required by 

paragraph (g) of this AD, no cracking is 

found, repeat the inspection required by 

paragraph (g) of this AD thereafter at 

intervals not to exceed 1,680 flight cycles. 

(i) If during any inspection required by 

paragraph (g) or (h) of this AD, any crack is 

found having a length between Points ‘A’ and 

‘B’ less than or equal to 0.15 inch and crack 

length between Points ‘C’ and ‘D’ less than 

or equal to 0.05 inch, as identified in Boeing 

Alert Service Bulletin MD90–55A016, 

Revision 1, dated February 17, 2010: Before 

further flight, blend out the crack; and within 

1,000 flight cycles after doing the blend out, 

do an HFEC inspection of the blend out on 

the center section rib hinge bearing lug; in 

accordance with the Accomplishment 

Instructions of Boeing Alert Service Bulletin 

MD90–55A016, Revision 1, dated February 

17, 2010. Repeat the HFEC inspection of the 

blend out thereafter at intervals not to exceed 

400 flight cycles until the replacement 

specified by paragraph (j) is done. 

(j) If any cracking is detected during any 

inspection required by paragraph (i) of this 

AD, before further flight, replace the 

horizontal stabilizer center section rib with a 

new horizontal stabilizer center section rib, 

in accordance with the Accomplishment 

Instructions of Boeing Alert Service Bulletin 

MD90–55A016, Revision 1, dated February 

17, 2010. 

(k) If during any inspection required by 

paragraph (g) or (h) of this AD, any crack is 

found having a length between Points ‘A’ and 

‘B’ greater than 0.15 inch or crack length 

between Points ‘C’ and ‘D’ greater than 0.05 

inch, as identified in Boeing Alert Service 

Bulletin MD90–55A016, Revision 1, dated 

February 17, 2010: Before further flight, 

replace the horizontal stabilizer center 

section rib with a new horizontal stabilizer 

center section rib, in accordance with the 

Accomplishment Instructions of Boeing Alert 

Service Bulletin MD90–55A016, Revision 1, 

dated February 17, 2010. 

(l) For any airplane having a horizontal 

stabilizer center section rib replaced during 

the actions required by paragraph (j) or (k) of 

this AD: Before the accumulation of 7,200 

total flight cycles on the new horizontal 

stabilizer center section rib, do the actions 

required by paragraph (g) of this AD, and do 

all applicable actions specified in paragraphs 

(h), (i), (j), and (k) of this AD. 

Credit for Actions Accomplished According 

to Previous Issue of Service Bulletin 

(m) Actions accomplished before the 

effective date of this AD according to Boeing 

Alert Service Bulletin MD90–55A016, dated 

December 16, 2009, are considered 

acceptable for compliance with the 

corresponding actions required by 

paragraphs (g), (h), (i), (j), and (k) of this AD. 

Exceptions to the Service Bulletin 

(n) Where Boeing Alert Service Bulletin 

MD90–55A016, Revision 1, dated February 

17, 2010, specifies a compliance time ‘‘after 

the original issue date on the service 

bulletin,’’ this AD requires compliance within 

the specified compliance time after the 

effective date of this AD. 

Alternative Methods of Compliance 

(AMOCs) 

(o)(1) The Manager, Los Angeles ACO, 

FAA, has the authority to approve AMOCs 

for this AD, if requested using the procedures 

found in 14 CFR 39.19. Send information to 

ATTN: Roger Durbin, Aerospace Engineer, 

Airframe Branch, ANM–120L, FAA, Los 

Angeles Aircraft Certification Office (ACO), 

3960 Paramount Boulevard, Lakewood, 

California 90712–4137; telephone (562) 627– 

5233; fax (562) 627–5210. 

(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 principal maintenance inspector 

(PMI) or principal avionics inspector (PAI), 

as appropriate, or lacking a principal 

inspector, your local Flight Standards District 

Office. The AMOC approval letter must 

specifically reference this AD. 

(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 the 

Boeing Commercial Airplanes Organization 

Designation Authorization (ODA) that has 

been authorized by the Manager, Los Angeles 

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 23, 2010. 

Ali Bahrami, 

Manager, Transport Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. 2010–24715 Filed 9–30–10; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2010–0951; Directorate 

Identifier 2010–NM–107–AD] 

RIN 2120–AA64 

Airworthiness Directives; Learjet Inc. 

Model 45 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 

Model 45 airplanes. This proposed AD 

would require a general visual 

inspection for damage of wiring 

(including chafing, pinched wires, and 

exposed wires) and correct routing of 

wires in the left and right circuit breaker 

panels, and related investigative and 

corrective actions if necessary. This 

proposed AD results from reports of 

wire damage on the pilot and copilot 

circuit breaker panels caused by a short 

circuit between chafed wires. We are 

proposing this AD to detect and correct 

damaged or misrouted wires, which 

could result in a short circuit and the 

loss of systems associated with the 

wiring (including fire suppression 

function for one engine and essential 

avionics systems). 

DATES: We must receive comments on 

this proposed AD by November 15, 

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. 


jlentini on DSKJ8SOYB1PROD with PROPOSALS