14910-13-PI

DEPARTMENT OF TRANSPORTATION Federal Aviation Administration

(DOT). Airplanes RlN 2120-AA64

ACTION: Notice ofproposed ruJemaking (NPRM). smAlS'S1G 

# C~ n 

# "/'('0 vr'NG sn"'Q~



# . //4 

# ""1·'l Airworthiness Directives; The Boeing Company Model 737-300, -400, and -500 Series 

## t

# j 'l&vJt."---- 'MT~ 

# 3/25/10 AGENCY: Federal Aviation Administration (FAA), Department ofTransportation 14 CFR Part 39

# J-orc-0370 IDocket No. FAA-~-I t 1 I Ij Directorate 

### Identifier 2009-NM-210-AD)

SUMMARY: The FAA proposes to supersede an existing airworthiness directive (AD)
- I C'-c that applies to all Model 737-300, -400, and -500 series airplanes. The existing AD 

# :>If$;hnt~

m currently requires inspecting to determine ifcertain carriage spindles are installed, 

## Lf

# It 

## lO repetitive inspections for corrosion and indications ofcorrosion on affected carnage I~''''~I:S'S'':; spindles, and ifnecessary, related investigative and corrective actions. The existing AD also provides optional terminating action. This proposed AD would mandate the optiona I>AH terminating action, which would eliminate the need forthe repetitive inspections. The existing AD results from reports ofcorrosion found on carriage spindles that are located onthe outboard trailing edge flaps. We are proposing this AD to detect and correct corrosion ofthe carriage spindle, which could result in fracture. Fracture ofboth the I<QlnlNQ$"'''''''.

inboard and outboard carriage spindles, inthe forward ends through the large diameters, on aflap, could adversely affect the airplane's continued safe flight and landing. DATES: We must receive comments on this proposed AD by [insert date 45 days after 

## ".
date ofpublication inthe FEDERAL REGISTER]. ADDRESSES: You may send comments by any ofthe following methods:

• Federal eRulemaking Portal: Go to http://wwvv.regulations.gov. Follow the14910-13-P)

DEPARTMENT OF TRANSPORT AnON Federal Aviation Administration 14CFR Part 39 

### IDocket No. FAA-2009-1 IIII; Directorate Identifier 2009-NM-210-AD) RlN 2120-AA64 ROUnNG SYMBOL Airworthiness Directives; The Boeing Company Model 737-300, -400, and -500 Series AtXfH2'.t6/t\iH INITIALS/SIG Airplanes AGENCY: Federal Aviation Administration (FAA), Department ofTransportation (DOT). ACTION: Notice ofpropo~ed rulemaking (NPRM). SUMMARY: The FAA proposes to supersede an existing airworthiness directive (AD) that applies to all Model 737-300, -400, and -500 series airplanes. The existing AD I Z 10 OI,HlNG sv Ol (].J1l'\ -'Ub 'Hrrw.s,rS1G i<'1[; 

### u\~ Mn '/.~ 0 

### p 

# -,- fl.\.)M-' <oS 

## , currently requires inspecting to determine ifcertain camage spindles are installed, 10 spindles, and ifnecessary, related investigative and corrective actions. The existing AD 0 HGSYMIlOL 

### \o/? also provides optional terminating action. This proposed AD would mandate the optiona 

# zP'.)iL,.\1 eo terminating action, which would eliminate the need forthe repetitive inspections. The ATE' repetitive inspections for corrosion and indications ofcorrosion on affected carriage

existing AD results from reports ofcorrosion found on carriage spindles that are located 

## "'" on the outboard trailing edge flaps. Weare proposing this AD to detect and correct corrosion ofthe carriage spindle, which could result infracture. Fracture ofboth the inboard and outboard carriage spindles, inthe forward ends through the large diameters, on aflap, could adversely affect the airplane's continued safe flight and landing. DATES: We must receive comments on this proposed AD by [insert date 45 days after date ofpublication inthe FEDERAL REGISTER]. ADDRESSES: You may send comments by any ofthe following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the N1T1Al.SfSIG[4910-13-PJ

DEPARTMENT OF TRANSPORTA nON Federal Aviation Administration -O'>(VRRENCES OI)T!NG SYMBOL 14CFR Part 39 

### 1\1-0'- it) "ll1Al$i$JG [Docket No. FAA-2009-+++++; Directorate Identifier 2009-NM-210-AD)

.RIN 2120-AA64

I 2. 10 AGENCY: Federal Aviation Administration (FAA), Department ofTransportation ROUTI'IG SYMBOl Ainvorthiness Directivesj The Boeing Company Model 737-300, -400, and -500 Series Aum-Il.t,-sltJM l!'IlTIM.5{Slt,; Airplanes (DOT). ACTION: Notice ofproposed rulemaking (NPRM). SUMMARY: The FAA proposes to supersede an existing airworthiness directive (AD) that applies to allModel 737·300, -400, and ~500series airplanes. The existing AD OUTING sy OL

0""0 $ymb<>' 

## f\" i"\-n..oS currently requires inspecting to detennine ifcertain carriage spindles are installed, repetitive inspections for corrosion and indications ofcorrosion on affected carriage JD spindles, andifnecessary, related investigative and corrective actions. The existing AD 0 NGSYMBOL \~? also provides optional terminating action. Ibis proposed AD would mandate the optiona 

## z;lf)-zGVL.{) e terminating action, which would eliminate the need forthe repetitive inspections. The ATE existing AD results from reports ofcorrosion found on carriage spindles that are located G SYMBOL on the outboard trailing edge flaps. We are proposing this AD to detect and correct :')t"A 

### --1'tEq [I'll I IG corrosion ofthe carriage spindle, which could result infracture. Fracture ofboth the inboard and outboard carriage spindles, inthe forward ends through the large diameters, 

## :'J..l

# r / /d OUTING sYMBOL on aflap, could adversely affect the airplane's continued safe flight and landing. DATES: We must receive comments onthis proposed AD by {insertdate 45 days after date ofpublication inthe FEDERAL REGISTER]. ADDRESSES: You may send comments by any ofthe following methods: 

### I'tWrn1

# tv';:> 'lmALS/SIG

• Federal eRulemaking Portal: Go to http://www.regulations.gov.Followthe NmAl.5(SJG