Acceptable methods, techniques, and practices : aircraft inspection and repair

812 Pages·1998·31.9 MB·English

by  United States. Federal Aviation Administration

advisory
o
,i^^^
U.S. Department
Circular
ofTransportation
AC 43.1 3-1 B with CHANGE
1
AC 43.1 3-2A Combined
ACCEPTABLE METHODSJECHNIQUES, AND
—
AND
PRACTICES AIRCRAFT INSPECTION REPAIR
DEPARTMENT OFTRANSPORTATION
Supplied by:
FEDERAL AVIATION ADMINISTRATION
Flight Standard Service Sanderson TrainingFrod^.tcis
RegulatorySupportDivision,AFS-600
Digitized by the Internet Archive
2010
in
http://www.archive.org/details/acceptablemethodOOunit
©
ADVISORY
U.S. Department
CIRCULAR
oTonspCoton
Federal Aviation
Adminsitration
AC CHANGE
B
43.1 3-1 with
1
AC
43.1 3-2A Combined
ACCEPTABLE
IVIETHODS,
TECHNIQUES, AND
—
PRACTICES AIRCRAFT
INSPECTION AND REPAIR
CONSOLIDATED REPRINT
Incorporates change
1
(sections added/changed by change 1 are
denoted by a change bar beside the paragraph
number in the table of contents)
DEPARTMENT OF TRANSPORTATION
FEDERALAVIATIONADMINISTRATION
FlightStandardService
RegulatorySupportDivision,AFS-600
Forsale byttie Superintendentot Documents; U.S. Government Printing Office; Washington, DC20402

(d
Advisory
U.S. Department
ofTransportation
Federal Aviation
Administration
Circular
TITLE 14 OF THE CODE OF FEDERAL REGULATIONS (14 CFR) GUIDANCE MATERIAL
Subject: ACCEPTABLE METHODS, Date: 9/8/98 AC No: 43.13-lB
TECHNIQUES,AND PRACTICES—AIRCRAFT Initiated by: AFS-640 Change: 1
INSPECTION AND REPAIR
1. PURPOSE. This advisorycircular(AC) contains methods, techniques, and practices acceptable tothe
Administratorforthe inspection andrepairofnonpressurized areas ofcivil aircraft, only whenthere are no
manufacturerrepairormaintenance instructions. This datagenerallypertainstominorrepairs. Therepairs
identified inthis AC mayonly be used as abasis forFAA approval formajorrepairs. The repairdatamay
also beusedas approveddata, andthe AC chapter, page, andparagraph listed inblock 8 ofFAA form337
when:
a. theuserhas determinedthat itis appropriatetotheproductbeingrepaired;
b. it is directlyapplicabletothe repairbeingmade; and
c. it isnot contraryto manufacturer's data.
2. CANCELLATION. The AC 43.13-1Adated 1988 is canceled.
3. REFERENCE: Title 14 ofthe Code ofFederal Regulations part43, section43.13(a) statesthat each
personperformingmaintenance, alteration, orpreventive maintenance on anaircraft, engine, propeller, or
appliance shallusethemethods,techniques, andpracticesprescribed inthe currentmanufacturer's maintenance
manual orInstructions forContinued Airworthiness preparedby its manufacturer, orothermethods, techniques,
orpractices acceptable tothe Administrator, exceptas noted insection43.16. FAA inspectors are preparedto
answerquestionsthatmayarise in this regard. Persons engaged inthe inspectionand repairofcivil aircraft
shouldbe familiarwith 14 CFRpart43, Maintenance, Preventive Maintenance, Rebuilding, and Alteration, and
part 65, SubpartsA, D, andE ofCertification: AirmenOtherThanFlight Crewmembers, andthe applicable
airworthinessrequirementsunderwhichthe aircraftwastype certificated.
4. ACKNOWLEDGMENTS. The FAA would like tothankthe followingpersons and organization fortheir
assistance inproducingAC 43.13-IB: Richard Finch, RichardFischer, Michael Grimes, Ray Stits, WilliamA.
Watkins, andthe SAE, Aerospace Electronics and Electrical Systems Division. Acknowledgment is also
extendedto all inthe aviation communitywho commented onthe document.
5. COMMENTS INVITED. Comments regardingthis AC shouldbe directedto DOT/FAA;
ATTN: Airworthiness Programs Branch, AFS-610; PO Box25082; Oklahoma City, OK73125
ActingDeputyDirector, FlightStandards Service
I
Page ii Par 1
B
1
9/8/98 AC 43.13-1
CONTENTS
Paragraph Page
CHAPTER WOOD STRUCTURE
1.
SECTION MATERIALSAND PRACTICES
1.
1-1. General I-l
1-2. Woods 1-1
Figiire 1-1. Relative ShrinkageofWoodMemberDuetoDrying 1-1
Table 1-1. SelectionandPropertiesofAircraftWood 1-3
Figure 1-2. TaperingofFaceplate 1-3
1-3. ModifiedWoodProducts - 1-3
1-4. Adhesives 1-3
1-5. BondingPrecautions 1-5
1-6. PreparationofWood SurfacesforBonding 1-5
1-7. ApplyingtheAdhesive 1-6
1-8. AssemblyTime inBonding 1-6
1-9. BondingTemperature 1-6
1-10. ClampingPressure 1-7
1-11. MethodofApplyingPressure 1-7
1-12.—1-17. [RESERVED.] 1-8
SECTION HEALTHANDSAFETY
2.
1-18. General 1-9
1-19. SandinginAreasofExistingBondJointsandFinishes 1-9
1-20. HandlingofAdhesivesandFinishes 1-9
1-21.—1-26. [RESERVED.] 1-9
SECTION INSPECTION
3.
1-27. General 1-11
1-28. TypesofDeteriorationand Damage 1-1
1-29. InspectionMethods 1-11
Figure 1-3. LikelyAreastoIncurStructural Damage 1-13
1-30.-1-35. [RESERVED.] 1-14
SECTION REPAIRS
4.
1-36. General 1-15
1-37. ReplacementofDrainHoles and Skin Stiffeners 1-15
1-38. Control SurfaceFlutterPrecautions 1-15
1-39. ScarfJoints 1-15
Figure 1-4. ConsiderationofGrainDirectionWhenMakingScarfJoints 1-15
1-40. SplicingofSpars 1-15
Figure 1-5. MethodofSplicing SolidorLaminatedRectangularSpars 1-17
Figure 1-6. MethodofSplicing Solid'T' Spars 1-18
Figure 1-7. RepairstoBuilt-Up"I" Spar 1-19
Figure 1-8. MethodofSplicingBoxSparFlanges (Plate Method) 1-20
1-41. SparReplacement 1-16
1-42. SplicingofBoxSparWebs 1-16
Figiu^e 1-9. MethodofSplicingBox SparWebs 1-21
1-43. ReplacingSolid-Type SparsWithLaminated-Type Spars 1-16
Page
iii
B
AC 43.13-1 9/8/98
CONTENTS (CONTINUED)
Paragraph P^ge
1-44. SparLongitudinal CracksandLocal Damage 1-16
Figure 1-10. MethodofReinforcingaLongitudinal Crackand/orLocal Damage ina Solid Spar 1-22
1-45. ElongatedHoles in Spars 1-18
1-46. Rib Repairs 1-18
Figure 1-11. RepairofWoodRibs 1-23
Figure 1-12. Tj'pical WingCompressionRibRepairs 1-24
1-47. Plywood Skin Repair 1-20
1-48. Detennination ofSingleorDouble Curvature 1-20
1-49. Repairsto Single Curvature Plywood Skin 1-20
Table 1-2. MinimumRecommended Bend Radii forAircraftPlywood 1-25
1-50. Repairsto DoubleCurvature Plywood Skin 1-22
1-51. TypesofPatches 1-25
Figure 1-13. SplayedPatch 1-27
Figure 1-14. SurfacePatches 1-28
Figure 1-15. ScarfPatches(BackofSkinAccessible) 1-29
Figure 1-16. ScarfPatches(BackofSkinNotAccessible) 1-30
Figure 1-17. Oval PlugPatchAssembly 1-32
Figure 1-18. RoundPlugPatchAssembly 1-33
1-52. Fabric Patch 1-31
1-53.—1-63. [RESERVED.] 1-33
SECTION FINISHINGWOOD STRUCTURES
5.
1-64. General 1-35
1-65. AcceptableFinishes 1-35
1-66. Precautions 1-35
1-67. FinishingofInteriorSurfaces 1-36
1-68. FinishingofExteriorSurfaces 1-36
1-69. FinishingofEndGrain Surfaces 1-36
1-70. Finishingwith Fabric orTape 1-37
1-71. SealingofBolt Holes 1-37
1-72.—1-79. [RESERVED.] 1-37
CHAPTER FABRIC COVERING
2.
SECTION PRACTICESANDPRECAUTIONS
I.
2-1. General 2-1
2-2. ProblemAreas 2-1
2-3. Aircraft Fabric-Synthetic 2-1
2-4. AircraftFabric-Natural 2-2
Table2-1. CottonandLinen Fabrics 2-3
2-5. RecoveringAircraft 2-2
Table 2-2. CottonandLinen, TapesandThreads 2-4
2-6. Preparationofthe Structure forCovering 2-2
2-7. Fabric Seams 2-5
Figure 2-1.Fabric Seams 2-7
Figure2-2.Typical MethodsofAttachingFabric 2-8
2-8. CoveringMethods 2-9
Page iv
B
1
AC
9/8/98 43.13-1
CONTENTS (CONTINUED)
Paragraph Page
2-9. ReinforcingTape 2-10
Figure2-3. ExplodedSideViewofRib 2-10
2-10. Lacing 2-11
Figure2-4. StandardExternalModified SeineKnotUsedforSingleandDoubleRibLacing 2-1
Figure2-5. StartingStitchforRib Lacing 2-12
Figure 2-6. StandardSingle-Loop Lacing 2-13
Figure2-7. StandardKnotforDouble-Loop Lacing 2-14
Figure2-8. StandardDouble-LoopLacing(Optional) 2-15
Figure2-9a. Alternate SequencetoTieaModified SeineKnotforRibLacing 2-16
Figure2-9b. Alternate SequencetoTieaModifiedSeineKnotforRib Lacing 2-17
Figure2-9c. Alternate SequencetoTieaModified SeineKnotforRibLacing 2-18
Figure2-10. SpliceKnot 2-19
Figure2-11. BlindstitchLacing-SquareKnotSecuredwithHalfHitches 2-20
2-11. StitchSpacing 2-19
Figure2-12. FabricAttachment Spacing 2-21
2-12. Fasteners 2-21
2-13. FinishingTape 2-22
2-14. InspectionRings andDrainGrommets 2-22
2-15.^-19. [RESERVED.] 2-23
SECTION APPLICATIONOFDOPE
2.
2-20. General 2-25
Table2-3. SafetyTips forDope/Paint 2-26
Table 2-4. TipsforDoping 2-26
2-21. Dope ApplicationProcedure (Natural Fabrics) 2-26
2-22. CoveringOverPlywood 2-28
2-23. CoatingApplicationDefects 2-29
2-24.-^-29. [RESERVED.] 2-31
SECTION INSPECTIONANDTESTING
3.
2-30. General 2-33
2-31. Fabric Identification 2-34
2-32. CoatingIdentification 2-34
2-33. StrengthCriteriaforAircraftFabric 2-35
2-34. Fabric Testing 2-35
2-35. RejuvenationofDopeFilm 2-36
2-36.-^-41. [RESERVED.] 2-36
SECTION REPAIRSTOFABRICCOVERING
4.
2^2. General 2-37
2^3. RepairofTearsandAccessOpenings 2-37
Figure2-13 RepairofTearsinFabric 2-38
2-44. Sewn-PatchRepair 2-38
Figure2-14 Hand-StitchDetail 2-39
2-45. Doped-OnPatchRepair 2-39
2-46.—2-51. [RESERVED.] 2-40
PageV
B
111
AC 43.13-1 9/8/98
CONTENTS (CONTINUED)
Paragraph Vage
CHAPTER FIBERGLASS AND PLASTICS
3.
SECTION REPAIROFLIGHTLOADLAMINATE STRUCTURES
1.
3-1. General 3-1
3-2. Fiberglass Laminate Repairs 3-1
Figure 3-1. Typical Laminate(Facing)Repair 3-2
Figure 3-2. Typical Coreand FacingRepair 3-2
Figure 3-3. Typical SteppedJointRepair 3-3
3-3. RepairingHoles 3-3
Figure3-4. PreparingtheFiberglass Sandwich 3-3
Figure 3-5. ScarfedRepairtoaNonstructural LaminatedFiberglassComponent 3-4
Figure 3-6. Balanced Layup Same asOriginalNumberofPlies, PlusOneExtraPly 3-4
Figure 3-7. Typical ScarfJointRepair 3-5
Figure 3-8. CarefiillyCutTliroughEach LayerofFiberglassClothand
Remove it Fromthe DamagedArea 3-5
3-4. Sample BaggingandCuringProcess 3-5
Figure 3-9. Sample BaggingLayupCross Section 3-6
3-5.—3-9. [RESERVED.] 3-8
SECTION METALLIC SANDWICH SECONDARY STRUCTURE REPAIRS
2.
3-10. Repairsto Metallic SandwichSecondaryStructure 3-9
Figure3-10. Typical TypesofCoreReplacement 3-10
Figure 3-11. Typical Undercut CoreMaterial Cavity 3-10
Figure 3-12. Cross SectionofBondedand BoltedOverlap Repairs 3-1
Figure3-13. HoneycombCore Removal 3-1
Figure3-14. RemovingHoneycombCore fromaTaperedControl Surface 3-1
Figure 3-15. Removal ofCorewithCore Knife 3-11
Figure 3-16. DetailsofCoreRepair 3-12
3-11. Finishing 3-12
3-12.—3-17. [RESERVED.] 3-13
SECTION TRANSPARENTPLASTICS
3.
3-18. General 3-15
3-19. Storage and Handling 3-15
3-20. FormingProceduresandTechniques 3-15
3-21. Heating 3-16
Figure 3-17. HangingofAcrylic Sheets 3-16
3-22. Forms 3-16
3-23. Forming Methods 3-17
Table 3-1. Typical Temperatures forFormingAcrylic Sheets 3-17
Figure 3-18. Drill Havingan IncludedAngleofApproximately 150°,
Usedto Drill Acrylic Plastics 3-18
Figure3-19. UnibitDrill forDrillingAcrylic Plastics 3-18
Figure 3-20. ApplyingPressuretoAcrylic Plastics 3-19
Page vi