[4910-13-PI DEPARTM ENT OF T~SPORTA nON Federal Aviation Administration :::v;C" ••.•• "'ES

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### J4CFR Part 39 

## ·20 \I- CC:.-":') IOocket No. FAA-2&tft.: I I 1 I I ; Directorate Identifier 2009-Nl\1-228-ADI RIN 2120-AA64 Airwortbiness Directives; The Boeing Company Model 737·100, ~200, -200C, -300, -400, and -500 Series Airplanes AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice ofproposed rulemaking (NPR.i\1). SUMMARY: We propose to adopt anew airworthiness di.rective (AD) forcenain Mod 737-100, -200, -200e, -300, -400, and -500 series airplanes. This proposed AD would result inall airplanes having new relays with aground faultinterrupter (GFl) feature_ This proposed AD would require, depending on airplane confi&'uration, doing certain wiring changes, replacing the fuelpump power control rclays far the main, center and ,'. (z- 

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';'; 1-( AD also would require revising the maintenance program to incorponlle airworthiness 

## u-y' auxiliary tanks, as applicablc, with new relays having aGPI feature, perfamling certain bonding resistance mcasurements, and modifying relay module assemblies. The propos O<JII"" :m<ooI. I

consequent loss ofthe airplane.

DAYS AFTER DATE OF PUBLICATION [NTKE FEDERAL REGISTER]. airplanes). This proposed.W results from fuel system reviews conducted by {he limitations (AWLs) No. 28-AWL-23 (for Model 737-100, 737-200, and 737-200C sene '~:~ airplanes), and No. 28-AWL-22 (for Model 737-300, 737-400, and 737-500 series 'N"',"5r~l<; 

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# !v 0 (0 manufacturer. \Ve are proposing this AD 10 prevent damage to the fuel pumps caused b
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### /lNIIA-\O \ electrical arcing that could intTOducean ignition source in the fuel tauk, which, in :"

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combinalion with flammable fuel vapors, could result ina fuel tank explosion and

DATES: We must receive comments on this proposed AD by [INSERT DATE 4S14910-13-PI DEPARTMENT OF TRANSPORTA nON Federal Aviation Administration 

### J4CFR Part 39 :ot<rl,l~<:l;'<U, 

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# B:llit1I'L. ~", ••.<"~I\", mocket No. FAA-201O-+++++; Directorate Identifier 2009-NM-228-ADI RIN 2120-.0\.

.'\64 Airworthiness Directives; The Boeing Company Model 737-100, -200, -lODe, -300, -400, and -500 Series Airplanes AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice ofproposed rolel11aking (i'\rpRI\if). SUMMARY: We propose toadopt anew airworthiness directive (AD) forcenain Mod 737-100, -200, -200e, -300. -400, and -500 series airplanes. This proposed AD would result inall airplanes having new rclays with aground fault intenuptcr (GFf) feature. This proposed AD would require, depending on airplane configuration, doing certain

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## /11/ 1 manufacturer. We are proposing this AD to prevent damage to the fuel pumps caused b~-o.m,,,"S'14IIOI. airplanes). This proposed AD results from fuel system reviews conducted by the bonding resistance measurements, and modifying relay module assemblies. The propos AD also would require revising 

### the- maintenance program to incorporate airworthiness 

# ;~llqlIO limilalions (AWLs) No. 

### 28-AWL-23 (ForModel 737-100, 737-200, and 737-200C serie

# ~:·\lt.f airplanes), and No. 28·A WL-22 (for Model 737-300, 737-400, and 737.500 series ""noes/s'G wiring changes, replacing the fuel pump power control relays for the main, center and bf' auxiliary tanks, as applicable, with new relays having aGFI feature, performing certain

electrical arcing that could introduce an ignition source in the fuel tank, which. in 

## ...,~" combination \vith flammable fuel vapors, could result ina fuel tank explosion and consequent loss ofthe airplane
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# I DATES: We must receive cOnln;1entson this proposed AD by [INSERT DATE 45 

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### '-'''''~I.' DAYS AFTER DATE OF PUBLICA nON [NTHE FEDERAL REGISTER].