[4910-13-P]

14CFR Part 39 DEPARTMENT OF TRANSPORT AnON Federal Aviation Administration



# O:J-75 [Docket No. FAA-201O-1 IIII;Directorate Identifier 2009-NM-231-AD] RlN 2120-AA64 Airworthiness Directivesj The Boeing Company Model 747-100, 747-100B, ONClJRRJ:NCL> ROlJTrN(; "-MooL 

## W·~ INll1A'-",'G 

# 'J -1l!J
DATE 

# 1--11-/ 0 "Olfl'INGS\'MIlOL 

## -7 INmA'-"'S<G 

# C~ OATE 

### S/O'j /0 and 747SP Series Airplanes AGENCY: Federal Aviation Administration (FAA), DOT. 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400F, 747SR,

ACTION: Notice ofproposed rulemaking (NPRM). SUMMARY: We propose to adopt anew airworthiness directive (AD) for certain Mode
- 

## 101 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-40 

# :r~ 747-400F, 747SR, and 747SP series airplanes. This proposed AD would require reworking certain duct assemblies inthe environmental control system (ECS). This proposed AD results from reports ofduct assemblies inthe ECS with burned Boeing Material Specification (EMS) 8-39 polyurethane foam insulation. This proposed AD als results from areport from the airplane manufacturer that airplanes were assembled with kOllTl~G 'YMBOl 

## -lOa INITI.·\l-'i'IG 

# kB..\w"C1~ 11/0 .0· n< ,,.. Ol duct assemblies in the ECS \\iTappedwith BMS 8-39 polyurethane foam insulation, a I:<'TI,\'""SIG material ofwhich the fire retardant properties deteriorate with age. We are proposing thi P,\Tli AD toprevent apotential electrical arc from igniting the BMS 8-39 polyurethane foam .(jUTI~GS\·MB(j1.- insulation on the duct assemblies ofthe ECS, which could propagate a small fire and lea '~ITI,",'"SIG to alarger fire that might spread throughout the airplane through the ECS. DATES: We must receive comments on this proposed AD by [insert date 45 days after RQlJTING SYMBOL date ofpublication in the FEDERAL REGISTER]. JNIl'IAlS;S,(;

MTE

## 14910-I3-PI

DEPARTMENT OF TRANSPORT AnON Fedel"3l Aviation Administration 14CFR Part 39 {Docket No. FAA-2010-1 IIII; Directorate Identifier 2009-NM-231-AD) RIN 2120-AA64 OUllN!:; S1M~OL Airworthiness Directives; The Boeing Company Model 747-100, 747-1008, 

### Ih,.XJl~I~ 747-IOOB SUO, 747-200B, 747-200C, 747-200F,'747-300, 747-400, 747-400F, 747SR, 

# ,"ne~;:l~l\ (. ~ llf and 747SP Series Airplanes DATe 2-"-\0 AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice ofpropo~ed rulemaking (NPRM). 

### l\.M'H INIT1.llS,'$lG

OIlTI,HG sYM60l
" ('(l-j

## olb mAlSJS1G .••.•. 

# tf(~ '"

# _" /i/ I Material Specification (BMS) 8-39 polyurethane foam insulation. This proposed AD al results from areport from the airplane manufacturer that airplanes were assembled with duct assemblies inthe ECS wrapped with BMS 8~39polyurethane foam insulation, a 747-400F, 747SR, and 747SP series airplanes. This proposed AD would require SUMMARY: We propose to adopt anew airworthiness directive (AD) for certain Mod ,.•. ?- "\0 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300,747-40, ,- 

### ~-f£q NIT1Al.SlSIli 

## \,;;0 reworking certain duct assemblies inthe environmental control system (ECS). Thij; 

### ----...,

# ...----,. ..:.proposed AD results from reports of

### -duct assemblies inthe ECS with\.bu~ Boeing ( I ,. ~.' /-

material ofwhich the flre retardant properties deteriorate with age. We are proposing

AD to prevent apotential electrical arc from igniting the BMS 8-39 polyurethane foam insulation on the duct assemblies ofthe ECS, which could propagate asmall fire and Ie to alarger firethat might spread throughout the airplane through the ECS. DATES: We must receive comments on this proposed AD by [insert date 45 days after s 50S 

## DE NITIALSISIG

NIl1AlSJSlG date ofpublication inthe FEDERAL REGISTER].[4910-13-PJ

DEPARTMENT OF TRANSPORTATION Federal Aviation Administration

7..-'7-\0 

## '" ItllllALSiSJG [Docket No. FAA-2010-+++++; Directorate Identifier 2009-NM-23I-ADj RlN 2120-AA64 OI.lTJNGsmeOl Ainvorthiness Directives; The Boeing Company Model747~100, 747-100B, 

## ~n-J.3JsEm

. INInA1.5/SIG 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400F, 747SR, 

## e.-.,w\

, 'ttLlV' 

## ~" and 747SP Series Airplanes 14CFR Part 39

'cm100~ mAWSlG OIfTlNG sYMBOL AGENCY: Federal Aviation Administration (FAA), DOT.

747-400F, 747SR, and 747SP series airplanes. This proposed AD would require ACTION: Nolice ofproposed rulemaking (NPRM). SUMMARY: Wepropose to adopt anew airworthiness directive (AD) for certain Mod t" 

### "2-- " 0 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-40 

## """",m.' .5i'JJ-fI5

Material Specification (BMS) 8-39 polyurethane foam insulation. This proposed AD al reworking certain duct assemblies in the environmental control system (ECS). This proposed AD results from reports ofduct assemblies in the ECS with burned Boeing
results from areport from the airplane manufacturer that airplanes were assembled with ATE duct assemblies inthe ECS wrapped with BMS 8-39 polyurethane foam insulation, a OUTlNG SYMBOL material ofwhich the fire retardant properties deteriorate with age. We are proposing t is ISOS 

## O.E NInAlS/SIG AD to prevent apotential electrical arc from igniting the BMS 8-39 polyurethane foam b. DATE insulation on the duct assemblies ofthe ECS, which could propagate a small fire and Ie d 2... b

## /ro OUTlNG S~MIl0L to alarger fire that might spread throughout the airplane through the ECS. DATES: We must receive comments on this proposed AD by [insert date 45 days after date ofpublication inthe FEDERAL REGISTER]. N[llALS/SIG

NlllAl.5ISIG