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AC 43.13-1B  
ACCEPTABLE METHODS, TECHNIQUES, AND PRACTICES - AIRCRAFT INSPECTION AND REPAIR 
September 8, 1998 (Change 1 Incorporated)

Due to the size of this document in electronic format it is provided here as links to the individual sections.  Each downloaded section opens in a new browser window in .pdf format.

Chapter 1. Wood Structure

Section 1. Materials and Practices - Woods, Modified Wood Products, Adhesives, Bonding Precautions, Preparation of Wood Surfaces for Bonding, Applying the Adhesive, Assembly Time in Bonding, Bonding Temperature, Clamping Pressure, Method of Applying Pressure

Section 2. Health and Safety - Sanding in Areas of Existing Bond Joints and Finishes, Handling of Adhesives and Finishes

Section 3. Inspection - Types of Deterioration and Damage, Inspection Methods

Section 4. Repairs - Replacement of Drain Holes and Skin Stiffeners, Control Surface Flutter Precautions, Scarf Joints, Splicing of Spars, Spar Replacement, Splicing of Box Spar Webs, Replacing Solid-Type Spars With Laminated-Type Spars

Section 5. Finishing Wood Structures - Acceptable Finishes, Precautions, Finishing of Interior Surfaces, Finishing of Exterior Surfaces, Finishing of End Grain Surfaces, Finishing with Fabric or Tape, Sealing of Bolt Holes

Chapter 2. Fabric Covering

Section 1. Practices And Precautions - Problem Areas, Aircraft Fabric-Synthetic, Aircraft Fabric-Natural, Recovering Aircraft, Preparation of the Structure for Covering, Fabric Seams, Covering Methods, Reinforcing Tape, Lacing,  Stitch Spacing, Fasteners, Finishing Tape,  Inspection Rings and Drain Grommets

Section 2. Application Of Dope - Safety Tips for Dope/Paint, Tips for Doping, Dope Application Procedure (Natural Fabrics), Covering Over Plywood, Coating Application Defects

Section 3. Inspection And Testing - Fabric Identification, Coating Identification, Strength Criteria for Aircraft Fabric, Fabric Testing, Rejuvenation of Dope Film

Section 4. Repairs To Fabric Covering - Repair of Tears and Access Openings, Sewn-Patch Repair, Doped-On Patch Repair

Chapter 3. Fiberglass And Plastics

Section 1. Repair Of Light Load Laminate Structures - Fiberglass Laminate Repairs, Repairing Holes, Sample Bagging and Curing Process

Section 2. Metallic Sandwich Secondary Structure Repairs - Repairs to Metallic Sandwich Secondary Structure, Typical Types of Core Replacement, Typical Undercut Core Material Cavity, Honeycomb Core Removal, Removing Honeycomb Core from a Tapered Control Surface, Removal of Core with Core Knife, Details of Core Repair, Finishing

Section 3. Transparent Plastics - Storage and Handling, Forming Procedures and Techniques, Heating, Hanging of Acrylic Sheets, Forms, Forming Methods, Repair of Plastics, Stop-Drilling Cracks, Surface Patches, Plug Patch Repair, Cleaning and Polishing Transparent Plastic, Replacement Panels, Installation Procedures

Section 4. Windshields, Enclosures, And Windows - Temporary Repairs to Cracked Windshields or Windows, Protection, Windshield Installation

Chapter 4. Metal Structure, Welding, And Brazing

Section 1. Identification Of Metals - Ferrous (Iron) Alloy Materials, Identification of Steel Stock, Numerical System for Steel Identification, Interchangeability of Steel Tubing, Identification of Aluminum, Basic Temper Designations and Subdivisions from Aluminum Alloys

Section 2. Testing Of Metals - Hardness Testing, Rockwell Hardness Test, Brinell Hardness Test, Vickers Hardness Test, Microhardness Testing, Indentions, Magnetic Testing, Aluminum Testing, Hardness Values for Aluminum Alloys,

Section 3. Precautionary Measures - Flutter and Vibration Precautions, Load Factors for Repairs, Transfer of Stresses Within a Structure

Section 4. Metal Repair Procedures - Riveted (or Bolted) Steel Truss-Type Structures, Aluminum Alloy Structures, Selection of Aluminum for Replacement Parts, Heat Treatment of Aluminum Alloy Parts, Bending Metal, Setback, Riveting, Aircraft Rivet Identification, Rivet Hole Spacing and Edge Distance for Single-Lap Sheet Splices, Riveting Practice and Rivet Imperfections, Repair Methods and Precautions for Aluminum Structure, Typical Repair Method for Tubular Members of Aluminum Alloy, Repairing Cracked Members, Steel and Aluminum Fittings, Castings, Selective Plating in Aircraft Maintenance

Section 5. Welding And Brazing - Current and Polarity Selection for Inert Gas Welding, Common Defects to Avoid when Fitting and Welding, Torch Tip Sizes, Butt-Welding Strength Calculations, Equipment Selection, Accurately Identify the Type of Material to be Repaired, Preparation for Welding, Inspection of a Completed Weld, Microfissures, Nondestructive Testing, Practices to Guard Against, Torch Size (Oxyacetylene welding), Welding Rods and Electrodes, Rosette Welds, Heat-Treated Members, Types of Welding, Basic Gas-Welding Flames, Electric-Resistance Welding, Brazing, Aircraft Parts Not to be Welded, Welding Rod Selection, Repair of Tubular Members, Repair by Welded Sleeve, Repair by Bolted Sleeve, Welded-Patch Repair, Splicing Tubing by Inner-Sleeve Method, Splicing Tubing by Outer-Sleeve Method, Splicing Using Larger Diameter Replacement Tubes, Repairs at Built-In Fuselage Fittings, Engine-Mount Repairs, Built-Up Tubular Wing or Tail-Spars, Wing-Brace Struts and Tail-Brace Struts, Landing Gear Repair, Repairs to Welded Assemblies, Stainless Steel Structure

Section 6. Welding And Brazing Safety - Fire and Explosion Safety, Welding Work Area, Fire Protection, Protective Apparel, First-Aid Kits

Chapter 5. NonDestructive Inspection (Ndi)

Section 1. General - Approved Procedures, NDT Levels, Training, Qualification, and Certification, Flaws, Selecting the NDI Method, Advantages and Disadvantages of NDI Methods, Types of Inspections

Section 2. Visual Inspection - Simple Visual Inspection Aids, Borescopes, Typical Borescope Designs, Visual Inspection Procedures

Section 3. Eddy Current Inspection - Eddy Current Inspection, Generating an Eddy Current, Detecting an Eddy Current, Eddy Current Coils and Probes, Field Application of Eddy Current Inspection, Surface Inspection, Subsurface Inspection, Corrosion Inspection, Establishing Eddy Current Inspection Procedures

Section 4. Magnetic Particle inspection - Principles of Operation, Crack Detection by Magnetic Particle Inspection, Applications, Electrical Magnetizing Equipment, Materials Used in Magnetic Particle Inspection, Preparation of Surface, Methods of Examination, Application of Magnetic Particles, Magnetization, Determination of Field Strength, Special Examination Techniques, Demagnetization and Post-Examination Cleaning

Section 5. Penetrant inspection - Equipment Used in the Penetrant Inspection Process, Basic Steps to Perform Penetration Inspection, General Processing Procedures Flowsheet, Cleaners and Applicators, Technical Standards

Section 6. Radiography (X-Ray) inspection - Limitations, Film or Paper Radiography, Real-Time Radiography, Advantage of Real-Time Radiography Over Film Radiography, Computed Tomography (CT), Uses of Radiography, Comparison with Other NDI Methods, Flaws, Field Inspection, Safety

Section 7. Ultrasonic Inspection - Sound Reflection, Ultrasonic Inspection Techniques, Flaw Detection, Basic Equipment, Inspection of Bonded Structures, Bond Testing Instruments, Thickness Measurements, Leak Testing

Section 8. Tap Testing,  Section 9. Acoustic-Emission,  Section 10. Thermography,  Section 11. Holography,   Section 12. Shearography

Chapter 6. Corrosion, Inspection & Protection

Section 1. General -   Electrochemical Corrosion, Factors Influencing Corrosion, Common Corrosive Agents, Micro-Organisms

Section 2. Types Of Corrosion - General Surface Corrosion, Pitting Corrosion, Concentration Cell Corrosion, Active-Passive Cells, Filiform Corrosion, Intergranular Corrosion, Exfoliation Corrosion, Galvanic Corrosion, Stress Corrosion Cracking, Fatigue Corrosion, Fretting Corrosion

Section 3. Corrosion Protection Measures For Basic Materials - Anodizing and Related Processes, Plating, Phosphate Rust-Proofing, Chrome-Pickle Treatment, Dichromate Treatment, Stannate Immersion Treatment, Galvanic Anodizing Treatment, Cladding, Metal Spraying, Shot-Peening, Organic Coatings, Dope Proofing, Tube Interiors

Section 4. Corrosion Preventive Maintenance - Guidelines: All Aircraft, Guidelines: Aircraft Operating Over Salt Water

Section 5. Visual Corrosion Inspection Guide For Aircraft - Exhaust Trail Areas, Battery Compartments and Battery Vent Openings, Lavatories and Galleys, Bilge Areas, Wheel Wells and Landing Gear, External Skin Areas, Water Entrapment Areas, Engine Frontal Areas, Electronic Package Compartments, Flexible Hose Assemblies, Sandwich Panels, Control Cables, Integral Fuel Cells, Electrical Connectors

Section 6. Corrosion Removal Procedures - Safety Precautions, Corrosion Control Work Procedures

Section 7. Basic Corrosion Removal Techniques - Preparations for Rework, Fairing or Blending Reworked Areas, Abrasives for Corrosion Removal, Blendout of Corrosion as a Single Depression, Blendout of Multiple Pits in a Corroded Area, Corrosion Removal by Blasting, Cleaners, Polishes, and Brighteners, Standard Methods

Section 8. Aluminum And Aluminum Alloys - Special Treatment of Anodized Surfaces, Repair of Aluminum Alloy Sheet Metal, Corrosion Removal Around Countersunk Fasteners in Aluminum Alloy

Section 9. Magnesium And Magnesium Alloys - Treatment of Wrought Magnesium Sheets and Forgings, Repair of Magnesium Sheet Metal After Extensive Corrosion Removal, In-Place Treatment of Magnesium Castings

Section 10. Ferrous Metals - Special Treatment of High Strength Steel, Special Treatment of Stainless Steel, Example of Removing Corrosion from Ferrous Metals

Section 11. Other Metals And Alloys - Noble Metal Coatings - Cleanup and Restoration, Copper and Copper Alloys, Titanium and Titanium Alloys

Section 12. Plated Parts - Chromium and Nickel Plated Parts, Cadmium and Zinc Plated Parts

Section 13. Corrosion Proofing Of Land Planes Converted To Sea Planes - Necessary Minimum Precautions, Recommended Precautions

Section 14. Handling And Care Of Aircraft Recovered From Water Immersion - Initial Fresh Water or Detergent Wash, Reciprocating Engines and Propellers, Airframe

Chapter 7. Aircraft Hardware, Control Cables, And Turnbuckles

Section 1. Rivets - Material Applications

Section 2. Screws - Structural Screws, Machine Screws, Panhead Screws (NAS600 through NAS606, NAS610 through NAS616, NAS623, and NAS1402 through NAS1406), Self-Tapping Screws,Wood Screws

Section 3. Bolts - Bolts, Identification, Typical Aircraft Bolt Markings, Grip Length, Locking or Safetying of Bolts, Bolt Fit, Torques, Recommended Torque Values, Standard Aircraft Hex Head Bolts (AN3 through AN20), Drilled Head Bolts (AN73 through AN81), Engine Bolts, Close-Tolerance Bolts, Internal Wrenching Bolts (NAS144 through NAS158 and NAS172 through NAS176), Internal Wrenching Bolts (MS20004 through MS20024) and Six Hole, Drilled Socket Head Bolts (AN148551 through AN149350), Twelve Point, External Wrenching Bolts, (NAS624 through NAS644), Close-Tolerance Shear Bolts (NAS434), NAS6200 Series Bolts, Clevis Bolts (AN21 through AN36), Eyebolts (AN42 through AN49)

Section 4. Nuts - Self-Locking Nuts, Minimum Prevailing Torque Values for Reused Self-Locking Nuts, Nut Identification - Finishes, Castle Nut (AN310), Castellated Shear Nut (AN320), Plain Nut (AN315 and AN335), Light Hex Nuts (AN340 and AN345), Checknut (AN316), Wingnuts (AN350), Sheet Spring Nuts (AN365)

Section 5. Washers - Plain Washers (AN960 and AN970), Lockwashers (AN935 and AN936), Ball Socket and Seat Washers (AN950 and AN955), Taper Pin Washers (AN975)

Section 6. Pins - Taper Pins, Flathead Pins (AN392 through AN406), Cotter Pins (AN380), Spring Pins, Quick-Release Pins

Section 7. Safetying - Safety Wire, Securing Screws, Nuts, Bolts, and Snaprings, Safety-Wiring Procedures, Securing Oil Caps, Drain Cocks, and Valves, Securing Oil Caps, Drain Cocks, and Valves, Securing With Cotter Pins

Section 8. Inspection And Repair Of Control Cables And Turnbuckles - Cable Definitions, Flexible Cables, Flexible Cable Construction and Physical Properties, Nylon-Coated Cables, Nonflexible Cables, Cable Specifications, Cable Proof Loads, Replacement of Cables, Mechanically-Fabricated Cable Assemblies, Cable System Inspection, Internal Cable Wear, Pulley Wear Patterns, Corrosion and Rust Prevention, Wire Splices, Cable Maintenance, Cable Tension Adjustment

Section 9. Turnbuckles - Turnbuckle Installation, Turnbuckle Thread Tolerance, Witness Hole

Section 10. Safety Methods For Turnbuckles - Double-Wrap Method, Safetying Turnbuckles, Single-Wrap Method, Safety-Wire Secured Turnbuckles, Turnbuckle Safetying Guide, Securing Turnbuckles, Special Locking Devices, Assembling and Securing Clip-Locking Turnbuckles, Locking-Clip Application

Section 11. Hardware Identification Tables - Table of Rivets, Table of Screws, Table of Bolts, Table of Nuts, Table of Washers, Table of Pins

Chapter 8. Engines, Fuel, Exhaust, And Propellers

Section 1. Engines - Special Inspection, Crankshaft Inspection and Repair Requirements, Replacement Parts in Certificated Engines, Oil System Lines Inspection, Oil Filter Inspection, Cylinder Hold-Down Nuts and Cap Screws, Reuse of Safetying Devices, Self-Locking Nuts for Aircraft Engines and Accessories, Metallizing, Plating, Corrosion, Engine Run-In, Compression Testing of Aircraft Engine Cylinders, Spark Plugs, Operational Problems, Spark Plug Pre-Reconditioning Inspection, Ignition Harnesses Inspection, Magneto Inspection, Magneto-to-Engine Timing

Section 2. Fuel Systems - Fuel Lines and Fittings, Fuel Tanks and Cells, Fuel Tank Caps, Vents, and Overflow Lines, Fuel Cross-Feed, Firewall Shutoff, and Tank Selector Valves, Fuel Pumps, Fuel Filters, Strainers, and Drains, Indicator Systems, Fuel System Precautions

Secton 3. Exhaust Systems - Muffler/Heat Exchanger Failures, Manifold/Stack Failures, Internal Muffler Failures, Inspection, Repairs, Turbo-Supercharger, Augmentor Systems

Section 4. Repair Of Metal Propellers - Steel Blades, Aluminum Propeller Repairs, Repair Limits, Steel Hubs and Hub Parts, Propeller Hub and Flange Repair, Control Systems, Deicing Systems

Section 5. Inspection Of Propellers - Wood or Composition Propellers and Blades, Metal Propellers and Blades, Propeller Hub, Tachometer Inspection

Section 6. Propeller Tracking and vibration - Propeller Tracking Check, Vibration

Chapter 9. Aircraft Systems And Components

Section 1. Inspection And Maintenance Of Landing Gear - General Inspection, Cleaning and Lubricating, Fixed-Gear Inspection, Inspection of Retractable Landing Gear, Emergency Systems, Landing Gear Components, Floats and Skis, Inspection and Repair of Floats and Skis, Types of Landing Gear Problems, Special Inspections, Retraction Tests, Tire and Tube Maintenance, Tire Inspection and Repair, Inflation of Tires, Personal Safety, Disassemble the Wheel, Reassembling the Wheel, Slippage, Wheel Inspection, Wheel Installation

Section 2. Hydraulic Systems - Purposes of Hydraulic Systems, Types of Hydraulic Fluid, Handling Hydraulic Fluids, Hydraulic System Maintenance Practices, Hydraulic Lines and Fittings, Hose Assembly Instructions (Can Be Used for Low Pressure Hydraulic Fluid, Aircraft Hose Specifications, Proper Hose Installations

Section 3. Emergency Equipment - Life Rafts, Life Raft Inspections, Survival Kit Inspection, Special Inspections, Inspection Record, Raft Repairs, Repair Dimensions, Life Preservers, Life Preserver Inspection, Repair of Life Preservers, Miscellaneous Equipment, Oxygen Systems, Inspection, Maintenance, Functional Testing After Repair, Service Requirements --Oxygen Cylinders

Section 4. Cabin Interior - Car-3 Aircraft Interior, Part 23 Aircraft Interior, Source of Information, Upholstery and/or Belts

Chapter 10. Weight And Balance

Section 1. Terminology - Typical Datum Locations, Illustration of Arm (or Moment Arm), Example of Moment Computation, Empty Weight Center of Gravity Formulas, Operating Center of Gravity Range, Weighing Point Centerline

Section 2. Weighing Procedures - Procedures, Repairs and Alterations, Annual or 100-Hour Inspection, Weight and Balance Computations, Weight and Balance Extreme Conditions, Loading Conditions and/or Placards, Equipment List, Equipment Change, Effects of the Addition of Equipment Items on Balance, Sample Weight and Balance Report, Installation of Ballast, Loading Schedule

Chapter 11. Aircraft Electrical Systems

Section 1. Inspection And Care Of Electrical Systems - Inspection and Operation Checks, Functional Check of Check of Stand-By or Emergency Equipment, Cleaning and Preservation, Battery Electrolyte Corrosion, Adjustment and Repair, Insulation of Electrical Equipment, Bus Bars

Section 2. Storage Batteries - Battery Charging, Battery Freezing, Battery Maintenance, Electrolyte Spillage, Noxious Fumes, Installation Practices, Battery Ventilating Systems

Section 3. Inspection Of Equipment Installation - Installation Clearance Provisions, Wires, Wire Bundles, and Circuit Protective Devices, Alternator Diodes, Static Electrical Power Converters, Acceptable Means of Controlling or Monitoring the Electrical Load, Electrical Load Determination, Junction Box Construction

Section 4. Inspection Of Circuit-Protection Devices - Determination of Circuit Breaker Ratings, Rettable Circuit Protection Devices, Circuit Breaker Usage, Circuit Breaker Maintenance, Switches, Switch Derating Factors, Relays, Load Considerations, Operating Conditions for Switches and Relays

Section 5. Electrical Wire Rating - Methods for Determining Current Carrying Capacity of Wires, Instructions for Use of Electrical Wire Chart, Computing Current Carrying Capacity

Section 6. Aircraft Electrical Wire selection - Aircraft Wire Materials, Substitutions

Section 7. Table of acceptable wires - Open Airframe Interconnecting Wire, Protected Wire, Severe Wind and Moisture Problems (SWAMP), Shielded Wire

Section 8. Wiring Installation Inspection Requirements - Wiring Replacement, Terminals and Terminal Blocks, Fuses and Fuse Holders, Connectors, Junction Boxes, Panels, Shields, and Microswitch Housings, Conduit-Rigid Metallic, Flexible Metallic and Rigid Nonmetallic, Junctions, Circuit Breakers, System Separation, Electromagnetic Interference (EMI), interference Tests, Identification Stencils and Placards On Electrical Equipment

Section 9. Environmental Protection And Inspection - Maintenance and Operations, Group and Bundle Ties, Minimum Wire Bend Radii, Slack, Drip Loop in Wire Bundle, Power Feeders, RF Cable, Precautions, Moisture Protection, Wheel Wells, and Landing Gear Areas, Protection Against Personnel and Cargo, Heat Precautions, Movable Controls Wiring Precautions, Flammable Fluids and Gases, Separation of Wires From Plumbing Lines

Section 10. Service Loop Harnesses (Plastic Tie Strips) - Support, Anti-Chafing Material, Strain Relief, Service Loop

Section 11. Clamping - Safe Angle for Cable Clamps, Installing Cable Clamp to Structure, Clamping at a Bulkhead Hole, Wire and Cable Clamps Inspection

Section 12. Wire Insulation And Lacing String Tie - Insulation Materials, Stripping Insulation, Allowable Nicked or Broken Strands, Lacing and Ties, Single Cord Lacing, Double Cord Lacing, Insulation Tape

Section 13. Splicing - Staggered Splices in Wire Bundle

Section 14. Terminal Repairs - Attachment of Terminals to Studs, Studs and Insulators, Wire Terminals and Binding Posts, Crimp On Terminal Lugs and Splices, Lock Washers for Terminals On Equipment

Section 15. Grounding And Bonding - Grounding, Bonding, Bonding Inspection, Millivolt Drop Test, Bonding Jumper Installations, Creepage Distance, Fuel Systems, Electric Shock Prevention Bonding, Lightning Protection Bonding, Lightning Protection for Antennas and Air Data Probes, Static-Discharge Devices, Cleaning, Hardware Assembly

Section 16. Wire Marking - Wire Identification, Identification and Information Related to the Wire and Wiring Diagrams, Placement of Identification Markings, Spacing of Printed Identification Marks (Indirect Marking), Types of Wire Markings, Hot Stamp Marking, Dot Matrix Marking, Ink Jet Marking, Laser Marking, Identification Sleeves, Identification Tape, Operating Conditions, Installation of Printed Sleeves, Recommended Size of Identification Sleeving, Identification of Wire Bundles and Harnesses, Terminal Marking Sleeve and Tags, Sleeves and Cable Markers Selection, Temporary Wire Identification Marker, Marker Sleeve Installation After Printing

Section 17. Connectors - Types of Connectors, Voltage and Current Rating, Spare Contacts (Future Wiring), Installation, Feed-Through Bulkhead Wire Protection, Special Purpose Connector, Potting Compounds, Potting Connectors, Through Bolts

Section 18. Conduits - Size of Conduit, Conduit Fittings, Conduit Installation, Rigid Conduit, Flexible Conduit

Section 19. Protection Of Unused Connectors - Unpressurized Area Connectors, Pressurized Areas, Sealing Unused Contact Cavities-Unpressurized Areas

Section 20. Electrical And Electronic Symbols - Symbols, Electronic/Electrical Symbols

Chapter 12. Aircraft Avionics Systems

Section 1. Avionics Equipment Maintenance - Handling of Components

Section 2. Ground Operational Checks for Avionics Equipment (Electrical) - Inspection of Avionics System, Communication Systems, VHF Omni-Directional Range (VOR), Distance Measuring Equipment (DME), Automatic Direction Finder (ADF), Instrument Landing Systems (ILS), Marker Beacon, Long Range Navigation (LORAN), Global Positioning System (Gps), Autopilot Systems, Altimeters, Transponders, Emergency Locator Transmitters (Elt), Inspection of Elt, Flight Data Recorder, Cockpit Voice Recorders (Cvr), Weather Radar, Radome Inspection, Data Bus

Section 3. Ground Operational Checks for Avionics Equipment (Non Electrical) - Compass Check Swing, Pneumatic Gyros

Section 4. Pitot/Static System - System Components, Pitot/Static Tubes and Lines, Static Ports, Heater Elements, System Inspection, System Leak Test, Static System Test, Test Pitot System, Maintenance Precautions, Replacing Lines, Relocation of Pitot Tube, Troubleshooting the Pitot/Static Pressure System

Section 5. Avionics Test Equipment - Test Equipment Calibration Standards, Test Equipment Calibration

Chapter 13. Human factors

Human Factors - Human Factors Influence on Mechanic's Performance, The FAA Aviation Safety Program, Personal Minimum's Checklist

Appendix 1.  Glossary. (10 pages)  Appendix 2.  Acronyms and ABBREVIATIONS (4 pages)  Appendix 3.  Metric-Based Prefixes and Powers of 10 (1 Page)