AC 43.13-1B

Historical

Advisory circular · Acceptable Methods, Techniques, and Practices—Aircraft Inspection and Repair

A newer version is currentThis is a historical version. AC 43.13-1B CHG 1 Ed Update is the version in force, approved September 27, 2001.
Approved
September 8, 1998
Last reviewed
June 11, 2024
Cancelled by
AC43.13-1B CHG 1
Family
AC 43.13-1 · 7 versions
Revision
B
14 CFR parts
43, 65, 145, 21, 105, 23, 91, 121, 25
Cited by
95 ADs

Guidance, not mandatory unless a rule or AD requires it. DRS record last changed November 21, 2025.

Show pages 6–17

Contents (continued) Paragraph Page

Page xviii

4-86............................... SPLICING USING LARGER DIAMETER REPLACEMENT TUBES

.4-67

FIGURE 4-40.SPLICING USING LARG ER DIAMETER REPLACEMENT TUBE 4-69

4-87.............................................................. REPAIRS AT BUILT-IN FUSELAGE FITTINGS

.4-70

FIGURE 4-41................... REPAIRS AT BUILT-IN FUSELAGE FITTINGS 4-71

4-88............................................................................................ ENGINE-MOUNT REPAIRS

.4-70

4-89................................................................BUILT-UP TUBULAR WING OR TAIL-SPARS

.4-72

FIGURE 4-42......... STREAMLINE TUBE SPLICE USING ROUND TUBE

(APPLICABLE TO LANDING GEAR)4-73

4-90....................................................WING-BRACE STRUTS AND TAIL-BRACE STRUTS

.4-72

FIGURE 4-43........ STREAMLINE TUBE SPLICE USING SPLIT SLEEVE (APPLICABLE TO WING AND TAIL SURFACE BRACE STRUTS AND OTHER MEMBERS) 4-74

4-91................................................................................................LANDING GEAR REPAIR

.4-72

FIGURE 4-44......... STREAMLINE TUBE SPLICE USING SPLIT INSERT

(APPLICABLE TO LANDING GEAR)4-75

FIGURE 4-45.STREAMLINE TUBE SPL ICE USING PLATES (APPLICABLE TO

LANDING GEAR)4-76

FIGURE 4-46.REPRESENTATI VE TYPES OF REPAIRABLE AXLE ASSEMBLIES 4-77 FIGURE 4-47.LANDING GEAR ASSEMBLIES THAT CANNOT BE REPAIRED BY WELDING 4-78

4-92...........................................................................REPAIRS TO WELDED ASSEMBLIES

.4-73

4-93..................................................................................STAINLESS STEEL STRUCTURE

.4-74

4-94.4-103. [RESERVED.]4-78

SECTION 6. WELDING AND BRAZING SAFETY

4-104GENERAL

.4-79

4-105..................................................................................FIRE AND EXPLOSION SAFETY

.4-79

4-106................................................................................................WELDING WORK AREA

.4-79

4-107.......................................................................................................FIRE PROTECTION

.4-79

4-108...............................................................................................PROTECTIVE APPAREL

.4-80

4-109.............................................................................................................FIRST-AID KITS

.4-80

4-110.4-128. [RESERVED.]4-80

Chapter 5. NonDestructive Inspection (Ndi) SECTION 1. GENERAL

Contents (continued) Paragraph Page

Page xix

5-1GENERAL

.5-1

5-2.............................................................................................APPROVED PROCEDURES

.5-1

5-3......................................................................................................................NDT LEVELS

.5-1

5-4...................................................... TRAINING, QUALIFICATION, AND CERTIFICATION

.5-2

5-5FLAWS

.5-2

5-6.......................................................................................SELECTING THE NDI METHOD

.5-5

TABLE 5-1. ADVANTAGES AND DI SADVANTAGES OF NDI METHODS 5-7

5-7................................................................................................ TYPES OF INSPECTIONS

.5-6

5-8.5-14. [RESERVED.]5-7

SECTION 2. VISUAL INSPECTION

5-15GENERAL

.5-9

5-16..............................................................................SIMPLE VISUAL INSPECTION AIDS

.5-9

5-17BORESCOPES

.5-10

FIGURE 5-1. ....................................... TYPICAL BORESCOPE DESIGNS 5-11

Contents (continued) Paragraph Page

Page xx

5-18........................................................................... VISUAL INSPECTION PROCEDURES

.5-10

FIGURE 5-2...........USING A FLASH LIGHT TO INSPECT FOR CRACKS 5-13

5-19.5-24. [RESERVED.]5-13

SECTION 3. EDDY CURRENT INSPECTION

5-25......................................................................................EDDY CURRENT INSPECTION

.5-15

FIGURE 5-3. ....................................GENERATING AN EDDY CURRENT 5-15 FIGURE 5-4. .......................................DETECTING AN EDDY CURRENT 5-15 FIGURE 5-5. ..................................... TYPICAL INSTRUMENT DISPLAYS 5-16

5-26........................................................................ EDDY CURRENT COILS AND PROBES

.5-15

5-27........................................... FIELD APPLICATION OF EDDY CURRENT INSPECTION

.5-15

5-28................................................................................................. SURFACE INSPECTION

.5-16

FIGURE 5-6. .............................................. TYPICAL SURFACE CRACKS 5-16

5-29..........................................................................................SUBSURFACE INSPECTION

.5-17

FIGURE 5-7. .......................................TYPICAL SUBSURFACE CRACKS 5-18

5-30............................................................................................CORROSION INSPECTION

.5-17

FIGURE 5-8. ................................TYPICAL STRUCTURAL CORROSION 5-18

5-31................................ESTABLISHING EDDY CURRENT INSPECTION PROCEDURES

.5-17

5-32.5-39. [RESERVED.]5-18

SECTION 4. MAGNETIC PARTICLE INSPECTION

5-40GENERAL

.5-19

5-41........................................................................................PRINCIPLES OF OPERATION

.5-19

FIGURE 5-9. ........................................... MAGNETIC FIELD DISRUPTED 5-19 FIGURE 5-10.CRACK DETECTION BY MAGNETIC PARTICLE INSPECTION 5-19

5-42APPLICATIONS

.5-20

5-43...................................................................ELECTRICAL MAGNETIZING EQUIPMENT

.5-20

5-44....................................... MATERIALS USED IN MAGNETIC PARTICLE INSPECTION

.5-20

TABLE 5-2... LISTING OF COMMONLY ACCEPTED STANDARDS AND ................SPECIFICATIONS FOR MA GNETIC PARTICLE INSPECTION 5-21

Contents (continued) Paragraph Page

Page xxi

5-45....................................................................................... PREPARATION OF SURFACE

.5-22

5-46........................................................................................METHODS OF EXAMINATION

.5-22

5-47.................................................................. APPLICATION OF MAGNETIC PARTICLES

.5-22

5-48MAGNETIZATION

.5-23

FIGURE 5-11. ............................................ CIRCULAR MAGNETIZATION 5-23 FIGURE 5-12. .................................... LONGITUDINAL MAGNETIZATION 5-24

5-49.....................................................................DETERMINATION OF FIELD STRENGTH

.5-25

5-50........................................................................SPECIAL EXAMINATION TECHNIQUES

.5-25

5-51......................................DEMAGNETIZATION AND POST-EXAMINATION CLEANING

.5-27

5-52.5-59. [RESERVED.]5-28

SECTION 5. PENETRANT INSPECTION

5-60GENERAL

.5-29

FIGURE 5- 13.......................... PENETRANT AND DEVELOPER ACTION 5-30

5-61........................... EQUIPMENT USED IN THE PENETRANT INSPECTION PROCESS

.5-29

TABLE 5-3.CLASSIFICATION OF PENETRANT INSPECTION MATERIALS

COVERED BY MIL-I-25135E5-30

Contents (continued) Paragraph Page

Page xxii

5-62.......................................BASIC STEPS TO PERFORM PENETRATION INSPECTION

.5-29

TABLE 5-4.. FLUORESCENT AND VI SIBLE PENETRANT INSPECTION ........................GENERAL PR OCESSING PROCEDURES FLOWSHEET 5-31 TABLE 5-5.PRE-CLEANING METH ODS FOR PENETRANT INSPECTION 5-32

5-63CLEANERS

.5-33

5-64. TECHNICAL STANDARDS5-34

TABLE 5-6... LISTING OF COMMONLY ACCEPTED STANDARDS AND

SPECIFICATIONS FOR ........................................................................PENET RANT INSPECTION 5-35

5-65.5-72. [Reserved.]5-35

SECTION 6. RADIOGRAPHY (X-RAY) INSPECTION

5-73GENERAL

.5-37

FIGURE 5-14RADIOGRAPHY

5-38

5-74LIMITATIONS

.5-37

5-75..................................................................................FILM OR PAPER RADIOGRAPHY

.5-37

5-76...........................................................................................REAL-TIME RADIOGRAPHY

.5-37

5-77.............ADVANTAGE OF REAL-TIME RADIOGRAPHY OVER FILM RADIOGRAPHY

.5-37

5-78.................................................................................COMPUTED TOMOGRAPHY (CT)

.5-37

5-79..............................................................................................USES OF RADIOGRAPHY

.5-38

5-80...............................................................COMPARISON WITH OTHER NDI METHODS

.5-38

5-81FLAWS

.5-39

5-82........................................................................................................ FIELD INSPECTION

.5-39

5-83SAFETY

.5-39

5-84.5-88. [RESERVED.]5-39

SECTION 7. ULTRASONIC INSPECTION

5-89GENERAL

.5-41

FIGURE 5- 15ULTRASOUND

5-42

5-90.....................................................................................................SOUND REFLECTION

.5-41

5-91..................................................................ULTRASONIC INSPECTION TECHNIQUES

.5-41

FIGURE 5-16.PULSE-ECHO AND T HROUGH-TRANSMISSION ULTRASONIC

INSPECTION TECHNIQUES5-42

Contents (continued) Paragraph Page

Page xxiii

5-92..........................................................................................................FLAW DETECTION

.5-41

5-93........................................................................................................ BASIC EQUIPMENT

.5-41

FIGURE 5-17.TYPICAL PORTABLE ULTRASONIC INSPECTION INSTRUMENT 5-43 FIGURE 5-18.................EXAMPLE OF POSITION FIXTURE AND SHOE 5-44 FIGURE 5-19.EXAMPLE OF THE U SE IF A TRANSDUCER POSITIONING FIXTURE 5-44 FIGURE 5-20........EXAMPLE OF A TYPICAL REFERENCE STANDARD 5-44

5-94................................................................... INSPECTION OF BONDED STRUCTURES

.5-43

FIGURE 5-21.EXAMPLES OF BONDED STRUCTURE CONFIGURATIONS

AND SUGGESTED INSPECTION COVERAGE5-47

TABLE 5-7........ ACCEPTABLE UL TRASONIC INSPECTION METHODS

ASSOCIATED WITH THE EXAMPLE BONDED STRUCTURE CONFIGURATIONS SHOWN IN FIGURE 5-

21. 5-48 TABLE 5-8.ULTRASONIC INSPECTION METHODS FOR BONDED STRUCTURES 5-49

5-95................................................................................... BOND TESTING INSTRUMENTS

.5-46

5-96..................................................................................... THICKNESS MEASUREMENTS

.5-50

5-97................................................................................................................LEAK TESTING

.5-50

5-98.5-104. [RESERVED.]5-51

Contents (continued) Paragraph Page

Page xxiv SECTION 8. TAP TESTING

5-105GENERAL

.5-53

FIGURE 5-22. ................................SAMPLE OF SPECIAL TAP HAMMER 5-53

5-106.5-111. [RESERVED.]5-53

SECTION 9. ACOUSTIC-EMISSION

5-112GENERAL

.5-53

5-113APPLICATIONS

.5-54

5-114.5-119. [RESERVED.]5-54

SECTION 10. THERMOGRAPHY

5-120GENERAL

.5-54

5-121.5-126. [RESERVED.]5-54

SECTION 11. HOLOGRAPHY

5-127GENERAL

.5-54

5-128.5-133. [RESERVED.]5-54

SECTION 12. SHEAROGRAPHY

5-134GENERAL

.5-55

5-135.5-140. [RESERVED.]5-55

Chapter 6. Corrosion, Inspection & Protection SECTION 1. GENERAL

6-1GENERAL

.6-1

FIGURE 6-1.SIMPLIFIED CORRO SION CELL SHOWING CONDITIONS

WHICH MUST EXIST FOR

ELECTROCHEMICA L CORROSION6-2

FIGURE 6-2. ELIMINATION OF CORROSION BY APPLICATION OF AN

ORGANIC FILM TO METAL SURFACE6-2

6-2......................................................................... FACTORS INFLUENCING CORROSION

.6-1

6-3....................................................................................COMMON CORROSIVE AGENTS

.6-3

6-4MICRO-ORGANISMS

.6-3

6-5.6-10. [RESERVED.]6-4

SECTION 2. TYPES OF CORROSION

6-11GENERAL

.6-5

FIGURE 6- 3........................................................... CORROSION ATTACK 6-5

6-12...............................................................................GENERAL SURFACE CORROSION

.6-5

Contents (continued) Paragraph Page

Page xxv FIGURE 6-4. .....................................GENERAL SURFACE CORROSION 6-5

6-13.................................................................................................... PITTING CORROSION

.6-5

FIGURE 6-5(A). PITTING CORRO SION (EXTERNAL VIEW)6-5

FIGURE 6-5(B). PITTING CORRO SION (MAGNIFIED CROSS SECTION) 6-5

Contents (continued) Paragraph Page

Page xxvi

6-14.........................................................................CONCENTRATION CELL CORROSION

.6-6

FIGURE 6-6. ...............................CONCENTRATION CELL CORROSION 6-6

6-15............................................................................................... ACTIVE-PASSIVE CELLS

.6-6

FIGURE 6-7.........................................................ACTIVE-PASSIVE CELL 6-7

6-16................................................................................................. FILIFORM CORROSION

.6-7

FIGURE 6- 8........................................................ FILIFORM CORROSION 6-7

6-17................................................................................... INTERGRANULAR CORROSION

.6-7

FIGURE 6-9. INTERGRANULAR CORROSION OF 7050-T6 ALUMINUM

ADJACENT TO STEEL FASTENER6-8

6-18.......................................................................................... EXFOLIATION CORROSION

.6-7

FIGURE 6- 10............................................... EXFOLIATION CORROSION 6-8

6-19................................................................................................GALVANIC CORROSION

.6-8

FIGURE 6-11.GALVANIC CORROSION OF MAGNESIUM ADJACENT TO

STEEL FASTENER6-9

6-20................................................................................STRESS CORROSION CRACKING

.6-8

FIGURE 6-12. ....................................STRESS CORROSION CRACKING 6-9

6-21...................................................................................................FATIGUE CORROSION

.6-9

6-22................................................................................................ FRETTING CORROSION

.6-10

FIGURE 6- 13..................................................... FRETTING CORROSION 6-10

6-23.6-28. [RESERVED.]6-10

SECTION 3. CORROSION PROTECTION MEASURES FOR BASIC MATERIALS

6-29GENERAL

.6-11

6-30....................................................................ANODIZING AND RELATED PROCESSES

.6-11

6-31PLATING

.6-11

6-32....................................................................................PHOSPHATE RUST-PROOFING

.6-11

6-33....................................................................................CHROME-PICKLE TREATMENT

.6-11

6-34..........................................................................................DICHROMATE TREATMENT

.6-11

6-35......................................................................... STANNATE IMMERSION TREATMENT

.6-11

6-36...........................................................................GALVANIC ANODIZING TREATMENT

.6-12

Contents (continued) Paragraph Page

Page xxvii

6-37CLADDING

.6-12

6-38..........................................................................................................METAL SPRAYING

.6-12

6-39SHOT-PEENING

.6-12

6-40.....................................................................................................ORGANIC COATINGS

.6-12

6-41........................................................................................................... DOPE PROOFING

.6-12

6-42........................................................................................................... TUBE INTERIORS

.6-12

6-43.6-49. [RESERVED.]6-12

SECTION 4. CORROSION PREVENTIVE MAINTENANCE

6-50........................................................................................ GUIDELINES: ALL AIRCRAFT

.6-13

6-51......................................GUIDELINES: AIRCRAFT OPERATING OVER SALT WATER

.6-13

6-52.6-62. [RESERVED.]6-14

SECTION 5. VISUAL CORROSION INSPECTION GUIDE FOR AIRCRAFT

6-63GENERAL

.6-15

6-64................................................................................................ EXHAUST TRAIL AREAS

.6-15

6-65................................BATTERY COMPARTMENTS AND BATTERY VENT OPENINGS

.6-15

6-66.........................................................................................LAVATORIES AND GALLEYS

.6-15

6-67..................................................................................................................BILGE AREAS

.6-15

6-68..........................................................................WHEEL WELLS AND LANDING GEAR

.6-15

Contents (continued) Paragraph Page

Page xxviii

6-69................................................................................................EXTERNAL SKIN AREAS

.6-15

6-70.....................................................................................WATER ENTRAPMENT AREAS

.6-16

6-71.............................................................................................ENGINE FRONTAL AREAS

.6-16

6-72................................................................ELECTRONIC PACKAGE COMPARTMENTS

.6-16

6-73......................................................................................FLEXIBLE HOSE ASSEMBLIES

.6-16

6-74.......................................................................................................SANDWICH PANELS

.6-16

6-75.........................................................................................................CONTROL CABLES

.6-16

6-76.................................................................................................INTEGRAL FUEL CELLS

.6-16

6-77........................................................................................ ELECTRICAL CONNECTORS

.6-16

6-78.6-88. [RESERVED.]6-16

SECTION 6. CORROSION REMOVAL PROCEDURES

6-89GENERAL

.6-17

6-90................................................................................................ SAFETY PRECAUTIONS

.6-17

6-91..........................................................CORROSION CONTROL WORK PROCEDURES

.6-18

6-92.6-112. [RESERVED.]6-19

SECTION 7. BASIC CORROSION REMOVAL TECHNIQUES

6-113GENERAL

.6-21

6-114................................................................................. PREPARATIONS FOR REWORK

.6-21

6-115........................................................... FAIRING OR BLENDING REWORKED AREAS

.6-21

TABLE 6-1........................... ABRASIVES FOR CORROSION REMOVAL 6-22 FIGURE 6-14...... TYPICAL EXAMPLE OF ACCEPTABLE CLEANUP OF

CORROSION PITS6-23

FIGURE 6-15.BLENDOUT OF CORROSION AS A SINGLE DEPRESSION 6-24 FIGURE 6-16.BLENDOUT OF MULTIPLE PITS IN A CORRODED AREA 6-24

6-116......................................................................CORROSION REMOVAL BY BLASTING

.6-22

6-117...........................................................CLEANERS, POLISHES, AND BRIGHTENERS

.6-22

6-118.................................................................................................STANDARD METHODS

.6-23

6-119.6-131. [RESERVED.]6-24

SECTION 8. ALUMINUM AND ALUMINUM ALLOYS

Contents (continued) Paragraph Page

Page xxix

6-132GENERAL

.6-25

6-133...................................................SPECIAL TREATMENT OF ANODIZED SURFACES

.6-25

6-134.........................................................REPAIR OF ALUMINUM ALLOY SHEET METAL

.6-25

6-135.CORROSION REMOVAL AROUND COUNTERSUNK FASTENERS IN ALUMINUM ALLOY

.6-26

6-136.EXAMPLES OF REMOVING CORROSION FROM ALUMINUM AND ALUMINUM ALLOYS

.6-26

6-137.6-147. [RESERVED.]6-28

SECTION 9. MAGNESIUM AND MAGNESIUM ALLOYS

6-148GENERAL

.6-29

6.149................... TREATMENT OF WROUGHT MAGNESIUM SHEETS AND FORGINGS

.6-29

6.150.REPAIR OF MAGNESIUM SHEET METAL AFTER EXTENSIVE CORROSION REMOVAL

.6-29

6.151...............................................IN-PLACE TREATMENT OF MAGNESIUM CASTINGS

.6-30

6.152................................. EXAMPLE OF REMOVING CORROSION FROM MAGNESIUM

.6-30

6-153.6-163. [RESERVED.]6-33