### Commercial Airplane Group 

# 737 Service Bulletin

Number: 737-53-1163 

## Summary Date: December 21, 1993 ATA System: 5313

SUBJECT:FUSELAGE - FORWARD ENTRY DOORWAY SKIN CUTOUT - UPPER FORWARD AND UPPER AFT CORNERS - INSPECTION, MODIFICATION, AND REPAIR

BACKGROUND Seventeen operators have found cracks in the upper corners of the forward entry door skin cutout. The airplanes had collected from 33,150 to 76,242 flight cycles. The cause of the cracks isfatigue fromcabin pressure. Continued operation with cracks in the doorway upper corners can result in cabin pressurization problems and unscheduled downtime for repairs. Installation of doublers as given in this service bulletin can prevent cracks at the doorway upper corners. ACTION Do a close visual inspection and a low and high frequency eddy current inspection for cracks at the forward entry doorway upper corners. If no cracks are found, repeat the inspection until the preventive change is done. If a crack is found, install the applicable repair kit. COMPLIANCE Do the inspections before the airplane has flown 27,000 flight cycles. If there are no cracks, do the inspection every 4500 flight cycles until the preventive change is done. If the airplane has flown more than 27,000 flight cycles, do the inspections before the airplane has flown 4500 more flight cycles. EFFECTIVITY All 737 airplanes, Line Numbers 1 through 1922 divided into 2 groups MANPOWER

Task Total Man-hours Elapsed Time (Hours) Inspection 3 3 Preventive Change 44 44 Repair 60 60

MATERIAL INFORMATION Boeing Supplied Kits Refer to Paragraph I.G., Material - Price and Availability.

BOEING COMMERCIAL AIRPLANE GROUP P.O. BOX 3707 SEATTLE, WASHINGTON 98124-2207 Summary Page 1 of 2

### BOEING SERVICE BULLETIN 737-53-1163



### FORWARD ENTRY DOOR

CORNER CRACKS TYPICAL UPPER

FWDC60078

Dec 21/93 Summary Page 2 of 2

### Commercial Airplane Group 

# 737 Service Bulletin

Number: 737-53-1163 Date: December 21, 1993 ATA System: 5313

SUBJECT:FUSELAGE - FORWARD ENTRY DOORWAY SKIN CUTOUT - UPPER FORWARD AND UPPER AFT CORNERS - INSPECTION, MODIFICATION, AND REPAIR

I. PLANNING INFORMATION A. Effectivity 1. Airplanes Refer to Service Bulletin Index Document D6-19567, Part 3 for Airplane Variable Number, Line Number, and Serial Number data. IDENTIFICATION BY CUSTOMER, CUSTOMER CODE, GROUP AND VARIABLE NUMBER
AER LINGUS (ARL)

1 PG255 PG573 PK029 PK641-PK642 PP951-PP952 PW591-PW594 2 PY281 PY322-PY323 AERO CONTROLS, INC (AEO)

1 PG629 AERO COSTA RICA (AOR)

1 PK872-PK873 AEROLINEAS ARGENTINAS (ARG)

1 PH705-PH708 PH741-PH743 PK102-PK103 2 PY007 AERON AVIATION (AAV)

1 PJ072 AIR ALGERIE (ALG)

1 PK361 PK631 PK633-PK634 PL717-PL725 2 PY051-PY053 AIR ATLANTA ICELANDIC (AID)

1 PJ104 2 PY002 PY381 AIR BERLIN GMBH (BER)

1 PW032 PW517 AIR CALEDONIE INTERNATIONAL (NCI)

1 PP918 AIR CHINA (BEJ)

1 PM281-PM283 PP521-PP522

Dec 21/93 737-53-1163 Page 1 of 23

### BOEING SERVICE BULLETIN 737-53-1163

AIR COLUMBUS (COB)

1 PP904 PP907 AIR EUROPA (ARE)

1 PM382 PP501-PP502 PP831 PP835 PP840 PP846 AIR FRANCE (AFA)

1 PL502-PL503 PN101-PN117 PP902 PP910-PP912 PT211 AIR GABON S.A. (GBN)

2 PY191 AIR GUINEE (GNE)

2 PY651 AIR HOLLAND CHARTER B.V. (HOL)

1 PP504 AIR MADAGASCAR (MAD)

1 PG375 PL793 AIR MALTA (MLT)

1 PL621-PL626 AIR NAMIBIA (NAM)

1 PN492 AIR NAURU (NAU)

1 PK356 PK581 2 PY286 AIR NEW ZEALAND, LTD. (ANZ)

1 PJ009 PK211 PK213-PK214 PK216-PK220 PM181 2 PY741 AIR NIPPON CO., LTD. (ANK)

1 PG582 AIR ONE AB SWEDEN (AOW)

1 PJ003 AIR TANZANIA (TNZ)

2 PY611-PY612 AIR TOULOUSE INTERNATIONAL (TOL)

1 PL716 AIR UK (LEISURE) (UKL)

1 PW001 PW014 PW017 PW051 AIR ZAIRE (ZAI)

2 PY111 PY113 AIR ZIMBABWE (ZMB)

1 PN431-PN433 ALASKA AIRLINES (ASA)

2 PY112 PY134-PY135 PY270 PY461-PY463

Dec 21/93 737-53-1163 2

### BOEING SERVICE BULLETIN 737-53-1163

ALL NIPPON AIRWAYS CO. LTD. (ANA)

1 PG584-PG586 PK711-PK716 ALOHA (ALO)

1 PG046 PK286-PK287 PK691-PK695 PK697 PP825-PP826 2 PY001 PY231 PY242 PY451 ALYEMDA DEM. YEMEN AIRLINES (ALY)

2 PY409-PY410 AMERICA WEST AIRLINES, INC. (AMW)

1 PC004 PG036 PK283 PK565 PK696 PL081 PL172 PL551-PL562 PL801 PP181-PP187 PP189 PP194-PP199 PP891-PP899 PP901 PP903 PP931-PP934 PS666-PS668 AMIRI FLIGHT (ABD)

1 PK495 ANGOLA AIRLINES (ANG)

1 PK661 PK664-PK666 2 PY162 ANSETT AIRLINES OF AUSTRALIA (ANS)

1 PP908-PP909 PP914 PQ026-PQ041 ANSETT WORLDWIDE AVIATION SERVICES (AWW)

1 PA001 ARAMCO ASSOCIATED CO. (ARM)

1 PL151 PL456 2 PY241 PY243-PY244 ARCO (ATR)

1 PN452-PN453 ARKIA ISRAELI AIRLINES, LTD (ARK)

1 PG575 ASEAN AVIATION (L) INC. (ASJ)

1 PG578-PG581 PG583 ASIANA AIRLINES (AAR)

1 PT212-PT213 PW005 PW007-PW009 PW011 PW013 PW018-PW020 PW025 ATASCO USA, INC. (ATJ)

1 PL762 AVENSA (AVN)

1 PK042-PK043 PM383 AVIATECA (AVT)

1 PG201 PL737 PL740-PL741 PP352 PP379 PP384 PP948 2 PY201 AVIATION SALES CO., INC. (ASC)

1 PG331 PG401

Dec 21/93 737-53-1163 3

### BOEING SERVICE BULLETIN 737-53-1163

AVIOGENEX AIR TRANSPORT (AVG)

1 PL501 PL506 PN501-PN502 BAVARIA (BAV)

1 PL455 BOURAQ INDONESIA AIRLINES (PTB)

1 PJ001 PL742-PL744 PL803 BRAATHENS S.A.F.E. (BRT)

1 PJ007-PJ008 PK882 PN455 PT021-PT023 PW571-PW573 BRITANNIA AIRWAYS, INC. (BRI)

1 PJ101 PJ108 PJ110-PJ111 PJ113-PJ115 PJ117-PJ119 PK801-PK804 BRITISH AIRWAYS (BAB)

1 PK731-PK765 PK771-PK777 PK779 PP353 PW091-PW093 PW111-PW112 PW115 PW117 BRITISH MIDLAND (BMA)

1 PP915-PP916 PP923-PP924 PQ281 PT295 PW004 PW006 PW501 CALDWELL AIRCRAFT TRADING CO. (CAS)

1 PG402 CAMEROON AIRLINES (CAM)

1 PM171 2 PY046-PY047 CANADIAN AIRLINES INTERNATIONAL LTD. (CDI)

1 PK028 PK358 PK671-PK675 PK677-PK681 PK822 PK881 PK884 PL401-PL417 PL764-PL770 PM141-PM142 2 PY151-PY154 PY303-PY304 PY421-PY422 PY441 CARNIVAL AIR (CVL)

1 PG302 PG305 PG312 PL712 PW061 CASINO EXPRESS (CIN)

1 PG279 PG436 CAYMAN AIRWAYS (CAY)

1 PK222 PK561 CHIA (CHS)

1 PW026 PW030 PW034-PW035 CHINA AIR LINES, INC. (CHI)

1 PN472-PN474 CHINA SOUTHERN AIRLINES (GUN)

1 PK636-PK637 PM251-PM254 PN405 CHINA SOUTHWEST AIRLINES (XIN)

1 PP631-PP634 COMAIR (CML)

1 PG354 PG356

Dec 21/93 737-53-1163 4

### BOEING SERVICE BULLETIN 737-53-1163

CONTINENTAL AIRLINES, INC. (CAL)

1 PA006-PA009 PA011-PA014 PA016-PA020 PG056 PG064 PG199 PG225 PG433 PG501-PG505 PG621-PG625 PG627-PG628 PG630 PG704 PL001 PP671-PP699 PP701-PP726 PP730 PP732-PP733 COPA COMPANIA PANAMENA DE AVIATION S.A. (COP)

1 PC001 PJ107 PJ112 PK617 PL745 2 PY341 CORSE AIR INTERNATIONAL (COR)

1 PW661 CROATIA AIRLINES (CRH)

1 PK904 PK906-PK907 PK928 PK932 DAMANIA AIRWAYS LTD. (DAI)

1 PL451-PL452 DELTA AIR LINES, INC. (DAL)

1 PK611 PK613 PK623-PK624 PK632 PL221 PL611 PN131-PN163 PN401-PN404 PN407-PN420 PP231-PP243 DEUTSCHE BA (DBA)

1 PP508 PP510 DUKE FARMS (DFI)

1 PP991 E G AND G (EGN)

1 PG037 PG208 PG210 PG215 PG431 PL763 EAST WEST AIRLINES (INDIA) (BOM)

1 PK615-PK616 PK819 PK824 PL171 PL758 EDRESS, SHIEKH M. (SME)

1 PL505 EGYPTAIR (EGP)

1 PK254-PK255 PK257-PK258 EL AL ISRAEL AIRLINES, LTD. (ELA)

1 PL631-PL632 ETHIOPIAN AIRLINES, CORP. (ETH)

1 PN512 EURALAIR (ERA)

1 PG026 PG028-PG029 PT146 2 PY004 PY006 EUROPE AERO SERVICE (EUR)

1 PK203 PK215 PK282 PK359 PK564 PK612 PQ228-PQ229 PT214 EUROPEAN AIRLINES (EUF)

1 PQ227

Dec 21/93 737-53-1163 5

### BOEING SERVICE BULLETIN 737-53-1163

FAR EASTERN AIR TRANSPORT (FAT)

1 PA002 PA005 PG055 PG226 PG228 PG230 PK562 PN481 FAUCETT (COMPANIA DE AVIATION S.A. (FCT)

1 PC002 PG034 PG213 PK241 PL711 FORTUNE AVIATION (FOR)

1 PK432 FRENCH POSTAL OFFICE (FPO)

1 PS641-PS642 2 PY101-PY103 PY302 PY342 PY344 GARUDA INDONESIAN AIRWAYS (GIA)

1 PQ282-PQ286 GATARI AIR SERVICE (GRI)

1 PL441 GERMANIA FLUGGESELLSCHAFT MBH (GER)

1 PP503 PP506-PP507 PQ231-PQ236 GOVERNMENT OF BRAZIL (BRZ)

1 PK068-PK069 GOVERNMENT OF MEXICO (MXG)

1 PC005 PG223 PP919 GOVERNMENT OF SHARJAH (SHJ)

1 PL581 GPA GROUP LTD. (GUI)

1 PK252 PK354-PK355 PK614 PL027 PP827 PP833-PP834 GULF AIR (GUL)

1 PK461-PK464 PK466-PK468 HAPAG LLOYD (HAP)

1 PL504 PT101 PW511-PW516 PW518 HEAVYLIFT AIRCRAFT ENGINEERING (HVL)

1 PJ109 ICELANDAIR (ICE)

1 PW561-PW563 INDIAN AIR FORCE (IDF)

1 PH712-PH713 PM016-PM017 INDIAN AIRLINES (IND)

1 PH021 PH024 PH709 PH711 PK231-PK233 PK235-PK240 PM001-PM006 2 PY631 INDONESIAN AIR FORCE (IDO)

1 PL601-PL603

Dec 21/93 737-53-1163 6

### BOEING SERVICE BULLETIN 737-53-1163

INTEGRATED RESOURCES (INH)

1 PG271 PG273 PJ006 INTER EUROPEAN AIRWAYS (IER)

1 PP841-PP842 PP922 PW116 INTERAMERICA S.A. DE C.V. (INJ)

1 PL761 INTERNATIONAL AIR LEASES (IAL)

1 PG043 PG047-PG048 PG253 INTERNATIONAL AIRLINE SUPPORT GROUP (ASG)

1 PG021 INTERNATIONAL LEASE FINANCE (ILF)

1 PL746 INTERNATIONAL PACIFIC TRADING CO. (IPT)

1 PG224 PG572 PG574 PJ102 IRAN AIR (IRN)

1 PH731 PK391 2 PY021-PY022 IRAQI AIRWAYS (IRQ)

2 PY141-PY142 ISTANBUL AIRLINES (IST)

1 PW002 PW022 PW024 PW028 PW036 JAPAN TRANSOCEAN AIR CO., LTD. (SWL)

1 PK521 PK523-PK528 PN451 PN454 PN456 JET AIRWAYS (INDIA) PVT. LTD. (JPL)

1 PP920-PP921 JETALL HOLDING CORPORATION (JEL)

2 PY005 JUGOSLOVENSKI AEROTRANSPORT (JAT)

1 PP771-PP779 KENYA AIRWAYS (KEN)

1 PK253 PK256 KLM ROYAL DUTCH AIRLINES (KLM)

1 PP861-PP873 PW611-PW615 KOREAN AIR FORCE (KAF)

1 PP221 LACSA (LAC)

1 PK357 PK871 LADECO (LDE)

1 PJ005 PK212 PK281 PK826 PK830 PL802 PP946

Dec 21/93 737-53-1163 7

### BOEING SERVICE BULLETIN 737-53-1163

LAN-CHILE S.A. (LAN)

1 PK360 PK825 PL025 PL028 LAPA (LAZ)

1 PG355 PK047 PK051 LAUDA AIR LUFTFAHRT AG (LAL)

1 PP851-PP852 LIBERTY AIRLINE, LTD. (LIR)

1 PJ004 LINA CONGO (LNA)

2 PY411 LINHAS AEREAS DE MOCAMBIQUE (LAM)

1 PH703 2 PY031 LITHUANIAN AIRLINES (LIJ)

1 PK563 LUFTHANSA GERMAN AIRLINES (DLH)

1 PK901-PK903 PK905 PK911-PK927 PK929-PK931 PK933-PK938 PQ051-PQ073 PQ086-PQ092 2 PY345-PY346 MAERSK AIR (MRS)

1 PP505 PT121 PT123 MALAYSIAN AIRLINES SYSTEM BERHAD (MAS)

1 PL747 PW027 PW031 PW033 PW062-PW063 MALEV HUNGARIAN AIRLINES (HGA)

1 PK284-PK285 PK827 MANDALA AIRLINES (MND)

1 PL421 PN001-PN002 MARKAIR, INC. (ALK)

1 PN493 PP301 PP305 PQ226 PW113-PW114 PW502 2 PY056-PY057 PY592-PY595 MODILUFT (MOU)

1 PK908-PK910 MONARCH AIRLINES, LTD. (MON)

1 PM381 PP821 PP823-PP824 PP832 PP913 MONTELY II (MOY)

1 PJ031 MORRIS AIR (MOR)

1 PP162 PP164-PP165 PP169 PP188 PP190-PP192 PP201-PP205 PP302-PP304 PP351 PP378 PP381-PP382 PP727 NASA (NAS)

1 PA099

Dec 21/93 737-53-1163 8

### BOEING SERVICE BULLETIN 737-53-1163

NATIONAL AIRLINES (NAW)

1 PJ105-PJ106 NICA (NICARAGUENCE DE AVIACION) (NIC)

1 PK823 NIGERIA AIRWAYS, LTD. (NIA)

1 PL781-PL782 PL784-PL788 NORDIC EAST (NOE)

1 PJ002 NWT AIR (NTA)

2 PX701 PY132-PY133 OLYMPIC AIRWAYS (OLY)

1 PK301-PK304 PK307-PK310 PM021-PM023 P. T. AIRFAST (PTF)

1 PG204 PG278 2 PY343 PAKISTAN INTERNATIONAL AIRLINES CORP. (PIA)

1 PP281-PP286 PEGASUS AIRLINES (PGS)

1 PW029 PETROLAIR SYSTEMS S. A. (PTS)

1 PL471 PHILIPPINE AIRLINES, INC. (PAL)

1 PM384-PM385 PM387-PM388 PM390-PM391 PP935-PP936 PLM TRANSPORTATION EQUIPMENT CORP. (PLI)

1 PK820 PLUNA (PLU)

1 PL201-PL203 POLARIS AIRCRAFT LEASING CORP. (PLS)

1 PG202 PG205 PG207 PG211 PG218-PG219 PG272 PG274 PG276 PG651-PG652 PJ103 PK026-PK027 PK221 PK305 PK465 PK874 PL061 POLY TECHNOLOGIES, INC. (PTI)

1 PP728-PP729 POLYNESIAN AIRLINES (PLY)

1 PP947 PRESIDENTIAL AIR (PRB)

1 PG432 QANTAS AIRWAYS, LTD. (QAN)

1 PQ001-PQ016 PW531-PW535

Dec 21/93 737-53-1163 9

### BOEING SERVICE BULLETIN 737-53-1163

REPUBLIC OF NIGER (NIR)

2 PY166 ROYAL AIR MAROC (RAM)

1 PK271-PK274 PW631-PW632 2 PY671-PY672 SABENA S.A. (SAB)

1 PK041 PK044-PK046 PK048-PK050 PK052-PK053 PK431 PK433 PP961-PP967 PW010 PW503 2 PY272-PY275 SAHSA (SERVICIO AEREO DE HONDURAS,S.A.) (SAH)

1 PJ032 PJ071 PL736 SAUDI ARABIAN AIRLINES CORP. (SVA)

1 PK311-PK317 PL726-PL735 2 PY036-PY037 SAUDI ROYAL FLEET (SRF)

1 PK318 SCANDINAVIAN AIRLINES SYSTEM (SAS)

1 PT181-PT182 SERVICIOS AEREOS RUTAS ORIENTE, (SARO) (SEV)

1 PA015 PA021-PA022 PK351 PK353 SIERRA PACIFIC AIRLINES (SRP)

1 PC003 PG577 PK627 SILKAIR (SLK)

1 PM392 PP509 SINGAPORE AIRLINES, LTD (SIA)

1 PQ222 SOUTH AFRICAN AIRWAYS (SAA)

1 PG353 PL101-PL113 SOUTHWEST AIRLINES CO. (SWA)

1 PK082 PK091-PK099 PK541-PK560 PK621 PK628-PK630 PM051-PM066 PP101-PP148 PP161 PP163 PP166-PP168 PP193 PP380 PP731 PP822 PU001-PU007 SUDAN (SUD)

2 PY156-PY157 SULTANAIR (SLR)

1 PG251 SUNEXPRESS AIR (SNS)

1 PM389 T A PORTUGUESES (TAP)

1 PK971 PK973-PK974 PN081-PN086 PP984-PP986 PQ301-PQ305 2 PY721

Dec 21/93 737-53-1163 10

### BOEING SERVICE BULLETIN 737-53-1163

TACA INTERNATIONAL AIRLINES, INC. (TAC)

1 PG059 PG352 PK223 PN491 PQ331-PQ332 2 PY131 TAESA (TES)

1 PK625-PK626 TAT EUROPEAN AIRLINES (TTR)

2 PY003 PY301 PY321 PY361-PY362 TEA BASEL (TEB)

1 PP838 PP845 PQ224-PQ225 THAI AIR FORCE (TAF)

1 PK519 THAI AIRWAYS INTERNATIONAL, INC. (TII)

1 PK511 PK514-PK515 PW161-PW162 THE CIT GROUP/CAPITAL FINANCE CO. (TCI)

1 PK622 TRANS EUROPEAN AIRWAYS ITALIA S.P.A. (TEI)

1 PQ221 PQ223 TRANSAERO (TRX)

1 PK451-PK452 TRANSAVIA AIRLINES (TAV)

1 PG074 PK501-PK504 PK821 PP801-PP808 TRANSBRASIL AIRLINES INC. (TBL)

1 PP836-PP837 PP843-PP844 PP847-PP848 PQ241-PQ243 PW016 PW021 PW023 TRANSMED (TRZ)

1 PW012 PW015 TRANSTAR (AFM)

1 PG403 TRITON AIRLINES INC. (TTN)

1 PK352 TUNIS AIR (TUN)

1 PK861-PK863 2 PY621 UNITED AIR LINES, INC. (UAL)

1 PG001-PG004 PG006-PG013 PG015-PG019 PG022-PG025 PG027 PG030 PG032-PG033 PG038-PG040 PG045 PG051-PG054 PG057 PG060-PG063 PG065-PG072 PG075 PK201-PK202 PL002-PL023 PQ101-PQ198 UNITED STATES AIR FORCE (USF)

1 PJ201-PJ219

Dec 21/93 737-53-1163 11

### BOEING SERVICE BULLETIN 737-53-1163

USAIR, INC. (USA)

1 PG041-PG042 PG073 PG206 PG301 PG303-PG304 PG306-PG311 PG313-PG314 PG474 PG576 PK288-PK289 PK591-PK599 PK601-PK610 PK883 PM101-PM119 PN021-PN043 PP001-PP010 PP012-PP054 PP376-PP377 PP383 PP401-PP440 PP471-PP475 PV001-PV010 PV012-PV040 VARIG AIRLINES (VAR)

1 PK111-PK116 PK118-PK120 PK141-PK146 PL453-PL454 PP839 PP905-PP906 PP917 PP981-PP982 PP987 PQ251-PQ255 VARSA (VAB)

1 PG351 VASP (VSP)

1 PG435 PG437 PG439-PG440 PG471-PG473 PH011-PH013 PK061-PK062 PK065-PK067 PL756 2 PX071 VENEZUELA - GOVERNMENT OF (VNZ)

1 PK070 VISCOUNT AIR SERVICE INC. (VAS)

1 PG203 PG209 PG212 PG216-PG217 PG220-PG222 PK306 VIVA AIR (VIV)

1 PP391-PP393 PP983 WHIRLPOOL FINANCIAL CORP (ZZW)

1 PG214 WIEN AIRLINES (WIE)

2 PY401 XIAMEN AIRLINES CO. LTD. (XIA)

1 PK635 PM255 PN521 YEMEN AIRWAYS (YEM)

1 PK341 YUNNAN PROVINCIAL IMPORT & EXPORT CORP. (YUN)

1 PP651-PP652 ZAMBIA AIRWAYS (ZAM)

1 PK291 PL026

Dec 21/93 737-53-1163 12

### BOEING SERVICE BULLETIN 737-53-1163

IDENTIFICATION BY VARIABLE NUMBER GROUP 1 PA001-PA022 PA099 PA231-PA232 PC001-PC005 PG001-PG075 PG199 PG201-PG230 PG251-PG255 PG271-PG279 PG301-PG314 PG331-PG332 PG351-PG356 PG375 PG401-PG403 PG431-PG442 PG471-PG475 PG501-PG505 PG571-PG586 PG621-PG630 PG651-PG652 PG701-PG705 PH001 PH011-PH013 PH021-PH024 PH701-PH715 PH731-PH732 PH741-PH743 PJ001-PJ009 PJ031-PJ032 PJ071-PJ072 PJ101-PJ119 PJ201-PJ219 PK026-PK029 PK041-PK053 PK061-PK070 PK081-PK082 PK091-PK099 PK101-PK103 PK111-PK120 PK141-PK146 PK201-PK204 PK211-PK223 PK231-PK241 PK251-PK258 PK271-PK274 PK281-PK289 PK291 PK301-PK318 PK341 PK351-PK361 PK391 PK431-PK433 PK451-PK452 PK461-PK469 PK495 PK501-PK504 PK511-PK515 PK519 PK521-PK528 PK541-PK565 PK581 PK591-PK599 PK601-PK617 PK621-PK637 PK641-PK642 PK661-PK666 PK671-PK681 PK691-PK697 PK711-PK716 PK731-PK765 PK771-PK779 PK801-PK804 PK819-PK827 PK830 PK861-PK863 PK871-PK874 PK881-PK884 PK901-PK938 PK971-PK974 PL001-PL028 PL061 PL081 PL101-PL113 PL151 PL171-PL172 PL201-PL203 PL221 PL401-PL417 PL421 PL441 PL451-PL456 PL471 PL491 PL501-PL506 PL551-PL562 PL581 PL601-PL603 PL611 PL621-PL626 PL631-PL632 PL711-PL712 PL716-PL747 PL756 PL758 PL761-PL770 PL781-PL788 PL793 PL801-PL803 PM001-PM006 PM016-PM017 PM021-PM023 PM051-PM066 PM101-PM119 PM141-PM142 PM171 PM181 PM251-PM255 PM281-PM283 PM381-PM392 PN001-PN002 PN021-PN043 PN081-PN086 PN101-PN117 PN131-PN163 PN401-PN420 PN431-PN433 PN451-PN456 PN471-PN474 PN481 PN491-PN493 PN501-PN502 PN511-PN512 PN521 PP001-PP054 PP101-PP148 PP161-PP169 PP181-PP199 PP201-PP205 PP221 PP231-PP243 PP281-PP286 PP301-PP305 PP351-PP353 PP376-PP384 PP391-PP393 PP401-PP440 PP471-PP475 PP501-PP510 PP521-PP522 PP631-PP634 PP651-PP652 PP671-PP699 PP701-PP733 PP771-PP779 PP801-PP808 PP821-PP827 PP831-PP848 PP851-PP852 PP861-PP873 PP891-PP899 PP901-PP924 PP931-PP936 PP946-PP948 PP951-PP952 PP961-PP967 PP981-PP987 PP991 PP993 PQ001-PQ016 PQ026-PQ041 PQ051-PQ073 PQ086-PQ092 PQ101-PQ198 PQ221-PQ229 PQ231-PQ236 PQ241-PQ243 PQ251-PQ255 PQ281-PQ286 PQ301-PQ305 PQ331-PQ332 PS641-PS642 PS666-PS668 PT021-PT023 PT101 PT121-PT123 PT146 PT181-PT182 PT211-PT214 PT295 PU001-PU007 PV001-PV040 PW001-PW036 PW051 PW061-PW063 PW091-PW093 PW111-PW117 PW161-PW162 PW501-PW503 PW511-PW518 PW531-PW535 PW561-PW563 PW571-PW573 PW591-PW594 PW611-PW615 PW631-PW632 PW661 GROUP 2 PX071 PX701 PY001-PY008 PY021-PY022 PY031 PY036-PY037 PY046-PY048 PY051-PY053 PY056-PY057 PY101-PY103 PY111-PY113 PY131-PY135 PY141-PY143 PY151-PY154 PY156-PY157 PY161-PY162 PY166 PY191 PY201 PY221-PY222 PY231 PY241-PY244 PY270-PY275 PY281 PY286 PY301-PY304 PY321-PY323 PY341-PY346 PY361-PY362 PY381 PY401 PY409-PY411 PY421-PY422 PY441 PY451 PY461-PY463 PY591-PY595 PY611-PY612 PY621 PY631 PY651 PY671-PY672 PY721 PY741 2. Spares
None

Dec 21/93 737-53-1163 13

### BOEING SERVICE BULLETIN 737-53-1163

B. Reason Seventeen operators have found cracks in the upper corners of the skin at the forward entry doorway. The airplanes had collected from 33,150 to 76,242 flight cycles. The cause of the cracks is fatigue from cabin pressure loads. Continued operation with cracks in the doorway upper corners can result in cabin pressurization problems and unscheduled downtime for repairs. Installation of doublers as given in this service bulletin can prevent cracks at the doorway corners. There are four other service bulletins for 737 door cutout cracks. Table I shows the service bulletins and the areas they cover.
TABLE I - SERVICE BULLETINS FOR DOOR CUTOUT CRACKING DOORWAY Upper Forward Corner Upper Aft Corner Lower Forward Corner Lower Aft Corner Upper Hinge Cutout Lower Hinge Cutout Forward Entry 737-53-1163 737-53-1083 (a) Forward Galley 737-53-1116 Aft Entry 737-53-1149 737-53-1074 Aft Galley (a) Service Bulletin 737-53-1083 is for the lower sill
C. Description On Group 1 and 2 airplanes, do a close visual inspection and a high and low frequency eddy current inspection for cracks at the upper corners of the forward entry door. If you find no cracks and you don't do the preventive change, then you must make repeat inspections as shown in section II.D., Compliance. If you do a preventive change or a repair, then no more inspections are necessary. The preventive changes are shown in Section III., Accomplishment Instructions. If you find cracks, then you must do a repair. Stop drill the crack as given in 737 SRM 51-10-1 or 737-300/400/500 SRM 51-10-02 and install the repair kit given in section III., Accomplishment Instructions. The airplane effectivity is divided into two groups. Group 2 airplanes have a main cargo door immediately aft of the forward entry door. Group 1 airplanes do not have a main cargo door. An evaluation form is attached to this service bulletin. Please use this form to tell us what you think of the quality of this service bulletin.

Dec 21/93 737-53-1163 14

### BOEING SERVICE BULLETIN 737-53-1163

NOTES: 1. The changes specified in the service bulletins shown in Table I can be made before or during the changes specified in this service bulletin. 2. If the damaged area is more than the specified limits, write to Boeing for repair instructions. Give the size and location of the damage. When possible, send sketches and photographs. If the damage includes corrosion, send data on the length, width, and depth of clean up. SEND TO: BOEING COMMERCIAL AIRPLANE GROUP ATTENTION: MANAGER, AIRLINE SUPPORT D. Compliance Do the inspections before the airplane has flown 27,000 flight cycles. If there are no cracks, do the inspection every 4500 flight cycles until the preventive change is done. If the airplane has flown more than 27,000 flight cycles, do the inspections before the airplane has flown 4500 more flight cycles. E. Approval This service bulletin was examined by the Federal Aviation Administration (FAA). The changes specified in this service bulletin comply with the applicable Federal Aviation Regulations (FAR) and are FAA approved. The service bulletin and the FAA approval were based on the airplane in its original Boeing delivery configuration or as modified by other FAA approved Boeing changes and do not apply to airplanes on which other configuration changes have been made. F. Manpower The following table shows an estimate of the man-hours necessary to do this service bulletin for each doorway. This estimate is for direct labor only, done by an experienced crew. Adjust the estimate with operator man-hour data if necessary. The estimate does not include lost time. These are some examples of lost time: - Time to adjust to the workplace - Time to schedule the work - Time to examine the work - Time to cure the materials - Time to make the parts - Time to find the tools.

Task Number of Persons Man-Hours Elapsed Time (Hours) Inspection 1 3 3 Preventive Change 1 44 44 Repair 1 60 60

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### BOEING SERVICE BULLETIN 737-53-1163

G. Material - Price and Availability Boeing can supply the kits shown in Paragraphs II.A., Parts Necessary For Each Airplane, as shown below. Kit availability is shown in the Reorder Lead Time (ROLT). ROLT is calculated from the date Boeing gets the purchase order.
Unit Price ROLT Until Kit Number Name (weeks) Mar 13/94 65C36941-1 Kit - Preventive Change 25 $ 1948.00 65C36941-5 Kit - Repair 25 $ 1563.00 65C36941-7 Kit - Repair 25 $ 2120.00 65C36941-13 Kit - Preventive Change 25 $ 1697.00 65C36941-15 Kit - Repair 25 $ 1978.00 65C36941-17 Kit - Repair 25 $ 2360.00
The kits are subject to the terms and conditions of the Boeing standard purchase order acknowledgment. After the Unit Price date, new price (and ROLT ) data is applicable. Prices are in United States Dollars. Terms: Net 30 days. Send purchase orders and letters about the supply data to the Director of Spares and refer to this service bulletin number. H. Special Tools - Price and Availability
None I. Weight and Balance

Applicability Change in Weight (Pounds) Change in Moment (Pound-Inches) Group Kit 737-100 737-200 737-300 737-400 737-500 1 65C36941-1 +3.9 +1279.2 +1138.8 +967.2 +686.4 +1177.8 65C36941-5 +5.8 +1902.4 +1693.6 +1438.4 +1020.8 +1751.6 65C36941-7 +10.1 +3312.8 +2949.2 +2504.8 +1777.6 +3050.2 2 65C36941-13 +5.6

- +1635.2

- - - 65C36941-15 +7.6

- +2219.2

- - - 65C36941-17 +10.6

- +3095.2

- - -

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### BOEING SERVICE BULLETIN 737-53-1163

J. References 1. Existing Data: a. 737 Maintenance Manual Subject 25-21-331. b. 737-300/400/500 Maintenance Manual Subject 25-21-31 c. 737 Structural Repair Manual Subject 51-10-1, 51-30-8 d. 737-300/400/500 Structural Repair Manual Subject 51-10-02, 51-40-08 e. 737 Nondestructive Test Manual, Part 6, Subject 51-00-00 f. Boeing Standard Overhaul Practices Manual section 20-50-11, 20-50-12 g. Boeing Service Bulletins:
737-53-1074 "Fuselage - Entry and Galley Doorway Skin Cutouts - Inspection, Modification, and Repair" 737-53-1083 "Fuselage - Forward Entry Door Cutout Structure at Lower Sill - Inspection, Modification, and Repair" 737-53-1116 "Fuselage - Forward Galley Doorway Upper Corners - Inspection, Repair, and Modification" 737-53-1149 "Fuselage - Aft Galley and Aft Entry Doorway, Upper Corner Skin Cutout Inspection, Repair and Modification"

2. Data supplied with this service bulletin: a. Drawings: Drawing Number Sheet DCN ADCN Title 65C36941 PL - 1,2 Repair and Preventive Modification, Upper Forward Entry Doorway - Kit 1-- 2--
3. Installation Drawings:
None Boeing Process Specifications referred to on drawings are not given in this service bulletin since these procedures are frequently used as standard shop practices. K. Publications Changed
None
L. Electrical Load Data
None

Dec 21/93 737-53-1163 17

### BOEING SERVICE BULLETIN 737-53-1163

II. MATERIAL INFORMATION A. Parts Necessary For Each Airplane 1. To get the kits shown below, refer to Paragraph I.G., Material - Price and Availability. Airplane

Group Application Kit Number 1 Preventive Change 65C36941-1 1 Repair for Cracks in the Skin and Doubler, but not the Strap 65C36941-5 1 Repair for Cracks in the Skin, the Doubler, and the Strap 65C36941-7 2 Preventive Change 65C36941-13 2 Repair for Cracks in the Skin and Doubler, but not the Strap 65C36941-15 2 Repair for Cracks in the Skin, the Doubler, and the Strap 65C36941-17
2. Parts and Materials Supplied by the Operator: NOTE: Refer to 737 Structural Repair Manual Chapter 51 for alternative fasteners. Quantity Part Number (Specification) Name As Required BMS 5-95, Class B-1/2, -2, or -4 (a) Sealant (a) See Boeing Standard Practices Overhaul Manual, Subject 20-50-12

B. Parts Necessary to Change Spares
None C. Special Tools and Equipment No special tools or equipment are necessary to do the change in this service bulletin. But, it is possible that maintenance and overhaul tools in the manuals shown in Paragraph I.J., References, can be necessary. Examine operator tool supply to make sure all necessary tools are available. D. Existing Parts Accountability
None

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### BOEING SERVICE BULLETIN 737-53-1163

III. ACCOMPLISHMENT INSTRUCTIONS NOTES: 1. The paragraphs identified with letters give the general work instructions and the necessary tests. The instructions identified with numbers on the figures give the recommended sequence of steps. 2. Unless specified differently, these dimensions and tolerances are used:
- All linear dimensions are in inches - Tolerance on linear dimensions other than rivet and bolt edge margin is plus or minus 0.03 inch - Tolerance on rivet and bolt edge margin is plus or minus 0.05 inch - Angular tolerance is plus or minus 2 degrees - Fastener hole dimensions are in 737 Structural Repair Manual Chapter 51 - The torque limits to tighten nuts and bolts are found in 737 Structural Repair Manual Chapter 51. 3. Refer to 737 Structural Repair Manual Chapter 51 for alternative fasteners. 4. Refer to 737 Structural Repair Manual (SRM) Section 51-30-8 or 737-300/400/500 SRM Section 51-40-08 for countersink instructions and instructions on how to install countersink repair washers. 5. Refer to the Standard Overhaul Practices manual 20-50-11 for application of aerodynamic smoother. 6. Obey all warnings and cautions in the specified manual sections.

PART I - INSPECTION A. Get access to the passenger cabin side of the forward entry doorway upper corners by removing the sidewall lining panels. Refer to 737 Maintenance Manual (MM) Subject 25-21-331 or 737-300/400/500 MM Subject 25-21-31. B. Do a close visual inspection and a low and high frequency eddy current inspection for cracks in the skin, doubler and strap at the doorway upper corners as shown in Figure 1. C. If no cracks are found at the doorway upper corners, repeat the inspection at the times shown in the compliance section. Repeat the inspections until the preventive change is done as given in Part II. D. If cracks are found at the doorway upper corners, do the repair as given in Part III. NOTE: The repair given in Part III is applicable only to cracks that are found in the areas specified on drawing 65C36941, which is supplied with this service bulletin. If the crack is not in the area specified in drawing 65C36941, tell The Boeing Company. E. Return the airplane to normal. F. A Preventive change or repair is the last procedure necessary to complete this service bulletin.

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### BOEING SERVICE BULLETIN 737-53-1163

PART II - PREVENTIVE CHANGE A. Get access to the passenger cabin side of the forward entry doorway upper corners by removing the sidewall lining panels. Refer to 737 Maintenance Manual (MM) Subject 25-21-331 or 737-300/400/500 MM Subject 25-21-31. B. Remove the existing bolts and rivets as shown on the applicable kit drawing. For group 1 airplanes use kit drawing 65C36941-1, for group 2 airplanes use kit drawing 65C36941-13. C. Position the external doubler supplied in the preventive change kit. D. Through the existing fastener holes, backdrill the fastener holes in the external doubler as shown on the applicable kit drawing. E. Drill the new fastener holes at the locations shown on the applicable kit drawing. F. In the countersunk fastener holes that are covered by the external doubler, install the repair washers wet with sealant (refer to BMS 5-95). G. Assemble external doubler to fuselage skin with sealant (refer to BMS 5-95). H. Install the new fasteners as shown on the applicable kit drawing. NOTE: The fastener grip lengths shown on the drawing picture sheet are for the repair. The preventive change kits contain the correct fasteners for the preventive change doublers. I. Trim the external doublers flush with the existing door opening. J. Apply aerodynamic smoother to the edge of the external doublers except at the door cutout. Taper the aerodynamic smoother from the doubler edge to the fuselage skin.

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### BOEING SERVICE BULLETIN 737-53-1163

PART III - REPAIR NOTE: The repair given in this bulletin can only be used to repair a crack within the limits shown on the drawing supplied with this bulletin. On group 1 airplanes, see drawing 65C36941, Sheet 1, View B3. On group 2 airplanes, see drawing 65C36941, Sheet 2, View B3. Only cracks up to 2.5 inches in length and within the crack zone shown on the drawing can be repaired as given in this bulletin. See Flagnote 3 on the drawing. Contact Boeing for a repair if cracks exceed these limits. A. Get access to the passenger cabin side of the forward entry doorway upper corners by removing the sidewall lining panels. Reference 737 Maintenance Manual (MM) Subject 25-21-331 or 737-300/400/500 MM Subject 25-21-31. B. Stop drill the crack as given in 737 SRM 51-10-1 or 737-300/400/500 SRM 51-10-02. C. At the doorwayupper corners, remove the existing bolts and rivets as shown on the applicable kit drawing. See Section II, Material Information, for the applicable kit drawing. D. Position the external doubler and tripler supplied in the repair kit. E. Through the existing fastener holes, backdrill the fastener holes in the external doubler and tripler as given on the applicable kit drawing. F. Drill the new fastener holes at the locations shown on the applicable kit drawing. G. In the countersunk fastener holes that are covered by the external doubler, install the repair washers wet with sealant (refer to BMS 5-95). H. Assemble the external doubler and tripler to the fuselage skin with sealant (refer to BMS 5-95).

I. Install the new fasteners as shown on the applicable kit drawing. NOTE: The fastener grip lengths shown on the drawing are for the repair of cracks through the skin, the doubler, and the strap. The other kit, the kit for the repair of cracks through the skin and doubler only, contains the correct fasteners for that repair. J. Trim the external doublers flush with the existing door opening. K. Apply aerodynamic smoother to the edge of the external doublers except at the door cutout. Taper the aerodynamic smoother from the doubler edge to the fuselage skin.

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### BOEING SERVICE BULLETIN 737-53-1163



### 1 2 3 4

FORWARD ENTRY DOOR DOOR STRAP BODY SKIN

FWDC60117

The instruction numbers shown below agree with the numbers shown inside the circle symbols in the figure.
STEP TASK NAME PROCEDURE REFERENCES NOTES 1 InspectSkin High frequency eddy current NDT Part 6, 51-00-00, Figure 4Do the inspection on the outer surface. (a) (b) 2 InspectSkin, doubler, and door strapClose visual

_ Do the inspection on the inner surface. (a) (b) 3 Inspect Doubler and strap Low frequency eddy current NDT Part 6, 51-00-00, Figure 8Do the inspection from the outside. (a) (b) 4 InspectSkin Visual

- Do the inspection from the outside. (a) (b) (a) On group 1 airplanes, inspect an area that would be covered by the largest doubler shown on drawing 65C36941, Sheet 1, View B3.

FIGURE 1. INSPECTION

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### BOEING SERVICE BULLETIN 737-53-1163

(Continued)

(b) On group 2 airplanes, inspect an area that would be covered by the largest doubler shown on drawing 65C36941, Sheet 2, View B3.

FIGURE 1. INSPECTION

Dec 21/93 SHEET 2 OF 2 737-53-1163 23

### Commercial Airplane Group 

# 737 Service Bulletin

Number: 737-53-1163 

## Evaluation Form Date: December 21, 1993 ATA System: 5313 Prepared By: Steve Richmond

SUBJECT:FUSELAGE - FORWARD ENTRY DOORWAY SKIN CUTOUT - UPPER FORWARD AND UPPER AFT CORNERS - INSPECTION, MODIFICATION, AND REPAIR

Use this evaluation form to tell us what you think of the quality of this service bulletin. We will use the data that you give us to improve the quality of our service bulletins. Please include data about these or other items:- Did this service bulletin meet your estimate of quality? - How easy is this service bulletin to understand? - Are the Planning Information, Material Information and Accomplishment Instructions satisfactory? - Will you do this service bulletin fully? If not, please tell us why. - Is the Manpower estimate satisfactory? NOTE: Please do not use this evaluation form to tell us to make changes to your manuals. To make these changes, please use a Publication Change Request (PCR) form. Please give us this data: OPERATOR: TODAY'S DATE: PREPARED BY: TITLE: ORGANIZATION: TELEX CODE: TELEPHONE NUMBER:

COMMENTS:

If you have other comments please use the other side. Thank you for the time you used to complete this form. Give the completed evaluation form to your Boeing Field Service Representative or send the evaluation form directly to this address: R.G. Kelsey, Manager Service Bulletin Engineering Boeing Commercial Airplane Group P.O. Box 3707, Mail Stop 2L-02 Seattle, WA 98124-2207

BOEING COMMERCIAL AIRPLANE GROUP P.O. BOX 3707 SEATTLE, WASHINGTON 98124-2207