### require repetitive high frequency eddy current inspections forcracking ofthe aft face 0



### the hinge bearing lugs ofthe aft face ofthe horizontal stabilizer center section left and 14 CFR Part 39

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SUMJ\1ARY: We propose to adopt anew airworthiness directive (AD) for all McDonnell Douglas Corporation Model MD-90-30 airplanes. This proposed AD waul RIN 2120-AA64

ACTION: Notice nfproposed rulernaking (NPRM). Airworthiness Directives; McDonnell Douglas Corporation Model MD-90-30 Airpl Federal Aviation Administration

AGENCY: Federal Aviation Administration (FAA), DOT.



# OQ'53 {Docket No. FAA-2010-++++; Directorate Identifier 2010-NM-OIO-AD] DEPARTMENT OF TRANSPORTATION

right ribs, andrelated investigative and corrective actions ifnecessary. This proposed results fromreports ofcracks found on either the left, right, (orin one case both sides) the center section ribs ofthehorizontal stabilizer. We areproposing this AD todetect correct cracking inthehinge bearing lugs ofthe center section oftbe left and right ribs, which could result in failure ofthehinge bearing lugs and consequent inability ofthe horizontal stabilizer to sustain the required loads. DATES: We must receive comments on this proposed AD by [INSERT DATE 45 DAYS AFTER DATE OFPUBLICA nON INTHE FEDERAL REGISTER]. ADDRESSES: You may send comments by any ofthe following methods:

• Federal eRulemaking Portal: Go tohttp://www.regulations.gov. Follow the instructions for submitting comments .
• Fax: 202-493-2251.

FAA Form 1360-14.1 (6-89) OFFICIAL FILE COPY .1J.S.GPO;l ~ 1M.(I12f201011491O-13-Pj

DEPARTMENT OF TRANSPORT AnON Federal .o\"iationAdministration 14CFR Part 39 IDocket No. FAA-20IO-++++; Directorate Identifier 2010-NM-OIO-ADI RIN 2120-AA64 Ainvorthiness Directives; McDonnell Douglas Corporation Model MD-90-30 Airplanes AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice ofproposed rulemaking (NPRM). SUMMARY: We propose to adopt anew airworthiness directive (AD) for all McDonnell Douglas Corporation Model MD-90-30 airplanes. This proposed AD would require repetitive high frequency eddy current inspections for cracking ofthe aft face of the hinge bearing lugs ofthe aft face afthe horizontal stabilizer center section left and right ribs, and related investigative and corrective actions ifnecessary. This proposed AD results from repons of cracks found on either the left, right, (or inone case both sides) of the center section ribs ofthe horizontal stabilizer. We are proposing this AD to detect and correct cracking inthe hinge bearing lugs of lhc cenler section ofthe left and right ribs, which could result in failure ofthe hinge bearing lugs and consequent inability ofthe horizontal stabilizer to sustain the required loads. DATES: We must receive comments on this proposed AD by [INSERT DATE 45 DAYS AFTER DATE OF PUBLICA nON INTHE FEDERAL REGfSTER]. ADDRESSES: You may send comments by any ofthe foUowing methods:

• Federal eRulcmaking Portal: Go to http://www.regulations.£ov. Follow the instructions for submitting comments .
• Fax: 202-493-2251. , 

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FAA Fonn 1360·14.1 {6o.SS} OFFICIAL FILE COPY ~1I.9. GOVE~N••• ENTPRINTINGOFfiC!C '995. 

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