Sport Aviation Specialties
1512 Game Trail, Lawrenceville, GA 30044, 770-548-1206, www.sportaviationspecialties.com
Light-Sport Repairman Inspection (LSRI) Course- Airplane
Student Handout
Module 1- Introduction
 Instructor Contact Info
 G. Michael Huffman, 1512 Game Trail, Lawrenceville, GA 30044, 770-548-1206,
sportaviation@gmail.com
 LSRI Rating
 With the rating, you may perform the annual condition inspection on your own ELSA, but not on an
ELSA that you do not own. You may not perform the annual condition inspection on an SLSA, an EAB, or a type-certificated airplane that fits the LSA specifications.
 Take your course completion certificate to your FSDO office, which will issue the LS-I Repairman
certificate.
 LSA Specifications
 Light-sport aircraft (LSA)- an aircraft other than a helicopter or powered-lift that, since its original
certification, has continued to meet the following:
 Max takeoff weight- 1320 lbs (1430 seaplanes)
 Max speed of 120 kts at max power
 Max stall speed 45 kts
 Maximum seating capacity- 2 persons
 Single reciprocating engine, if powered
 Fixed or ground-adjustable prop (auto-feathering prop OK for powered gliders)
 Non-pressurized cabin
 Fixed landing gear
 Retractable landing gear OK for glider or seaplane
 Note: LSA is a generic term- nothing specified about the aircraft certification category
 A special light sport aircraft (SLSA):
 Is designed to meet LSA specifications
 Is certified by manufacturer to “consensus standards”
 May be sold complete, ready to fly
 May be offered in kit form
 May be built in certain other countries
 Cannot be modified unless approved by manufacturer
 All maintenance must be per maintenance manual
 Annual condition inspection & maintenance by A&P or light-sport repairman with “maintenance” rating
(LSRM)
 Consensus standards
 Developed by light aircraft industry for each aircraft class & common components
 Administered & published by ASTM
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 Address:
 Design & performance requirements
 Quality assurance requirements
 Production acceptance testing
 Continued airworthiness requirements
 Product information requirements
 An experimental light sport aircraft (ELSA):
 Is one of three kinds:
 Previously unregistered “ultralight-like” vehicle that meets LSA specs
 Must have been certificated before 1/31/2009- no more of these
 A kit version of an SLSA
 An SLSA the owner elects to convert to ELSA so he/she can make modifications & perform
maintenance
 Can be maintained by anybody
 Annual condition inspection by A&P, LSRM, or the owner as a light-sport repairman with an
“inspection” rating (LSRI)- this 16 hour course
Module 2- Regulations, Policies, & Guidance
 FAA Documents
 FAA documents are available on the Internet:
 Go to www.faa.gov
 Click the Regulations menu
 Click the document type you need & enter search criteria
 Option: Regulatory & Guidance Library (RGL)- rgl.faa.gov
 Will be replaced in 2022 by Dynamic Regulatory System (DRS)- drs.faa.gov
 The examples presented in this course do not represent an exhaustive list of regulations, policies, &
guidance. It is the responsibility of the person holding the LSRI certificate to maintain a detailed
knowledge of regulations, policies, & guidance that affect the privileges exercised under that certificate.
Nothing presented in this course shall be interpreted as superceding FAA regulations or guidance,
manufacturer’s safety directives, other applicable technical documents, or accepted practices for
aircraft design, maintenance, or inspection
 FAA 14 CFR Regulations of Interest
 1- Definitions & Abbreviations
 21- Certification Procedures
 39- Airworthiness Directives
 43- Maintenance, Rebuilding, & Alteration
 45- Identification & Registration Marking
 47- Aircraft Registration
 65- Certification of Other Airmen
 91- General Operating & Flight Rules
 Advisory Circulars of Interest
 AC 43.13-1B- Acceptable Methods, Techniques, & Practices- Aircraft Inspection & Repair
 AC 45-2C- Identification & Registration Marking
 AC 91-44A- Operation & Maintenance Procedures for ELTs
 Airworthiness Directives
 Bottom line concerning AD compliance
 For ELSAs, AD compliance is not required, but is “recommended” by the FAA
 If ADs are about known unsafe conditions, how can the aircraft be in a condition for safe
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operation without complying?
 Manufacturer’s Manuals and Safety Directives
 Manuals contain inspection, maintenance, and information the manufacturer considers “mandatory.”
However, the FAA does not consider it mandatory for ELSA.
 Manufacturers’ safety directives serve same purpose for SLSAs as ADs for type-certificated aircraft.
 Other Technical Documents of Interest
 Military specifications- MIL
 Military standards- MS
 Aerospace Material Specifications- AMS
 Technical Standard Orders- TSO
 Supplemental Type Certificates- STC
 Aircraft Registration
 Telling the FAA your aircraft exists
 Manufacturer/builder
 Model
 Serial number
 Obtaining an N-number and registration certificate
 Aircraft Certification
 Requires an inspection by FAA or a Designated Airworthiness Representative (DAR)
 Results in issuance of an airworthiness certificate & operating limitations
 FAA Registration Requirements
 Aircraft eligibility- §47.3(a)
 Requirement for registration- §47.3(b)
 Address change requirement- §47.45
 Re-registration every 3 yrs starting in 2010- now 7 yrs effective Jan 23, 2023
 FAA Certification Requirements
 Definition of categories & classes of aircraft- §1.1
 ELSA certification classes: airplane (fixed-wing), weight-shift (trikes), powered parachute, glider,
gyroplane, & lighter-than-air
 Airworthiness certificate types- §21.175
 Standard (white)
 Cessna, Piper, Beech, etc
 Special (used to be pink- now can be white)
 Primary
 Provisional
 Light-Sport- (SLSA)
 Limited
 Restricted- crop dusters, aerial survey, etc
 Experimental
 Research & Development
 Amateur Built
 Exhibition
 Air Racing
 To Show Compliance
 Crew Training
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 Market Survey
 Operating Light Sport (ELSA)- that’s us
 Special Flight Permit- ferry permits, etc
 ELSA certification categories
 Operating Light Sport Aircraft- §21.191(i)
 Previously unregistered air vehicles- §21.191(i)(1)
 SLSA manufacturer’s approved kit- §21.191(i)(2)
 “Converted” from SLSA certification- §21.191(i)(3)
 Duration of experimental airworthiness certificates- §21.181(a)(4)
 ELSA is unlimited (it doesn’t expire)
 Operating limitations- issued by FAA or a DAR when your ELSA is certificated
 Standard ELSA operating limitations are imposed by FAA Order
 FAA or DAR may impose other limitations deemed necessary
 Operating limitations may override FARs
 FAA Marking Requirements
 Fireproof data plate required- §21.182 & §45.11
 Definition of “fireproof”- §1.1
 Data plate information required- §45.13
 Manufacturer/builder’s name
 Model designations
 Builder’s serial number
 Experimental placard requirement- §45.23 & Operating Limitations
 N-Number specifications- §45.21
 Must be painted on or similar means of permanence
 Must have no ornamentation
 Must contrast with the background
 Must be legible
 N-Number location on fixed-wing aircraft- §45.25
 Horizontally on fuselage side
 Horizontally or vertically on vertical tail
 Other N-number specifications- §45.29
 Letter width, stroke width, & letter spacing
 Allowance for 3” numbers for ELSA
 Placards & markings for instruments & controls- §91.9 & Operating Limitations
 FAA Operational Requirements
 Requirement for identification & registration markings- §91.9(c)
 Requirement for current airworthiness & effective registration cert- §91.203
 Operating limitations for aircraft with experimental certificates- §91.9 & §91.319
 Requirements for instrumentation/equipment- §91.205 & Operating Limitations
 No requirements for day/VFR
 Requirements for night/VFR
 Airspeed, altimeter, mag compass, tach, oil temp/press, coolant temp, position lights, anticollision light, seat belts, shoulder harness, gear position indicator, spare fuses
 Landing light if flown for hire. Flotation gear and pyro signaling device, if flown for hire over
water
 Other requirements for IFR
 Installed instruments must be maintained per FAR 91
 Generally applies to transponder/encoder & ELT
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 Transponder requirements
 Equipment specifications- §91.215(a)
 Must be TSO’d
 Mode C altitude reporting required- §91.215(b)
 In Class A, B, or C airspace except with deviation
 Within 30 miles of “large” airports- App D Sect 1
 Exemption for aircraft “originally certified without an engine-driven electrical system.”
 VFR transponder & encoder check- 24 months- §91.413
 Done by FAA-certified repair station
 Check of transponder & encoder units themselves
 IFR altimeter/altitude report system check- 24 months- §91.411
 Done by FAA-certified repair station
 Includes VFR tests
 Also includes altimeter leak test & static system leak test
 ELT Requirements-§91.207
 Equipment must meet TSO C91a or TSO C126
 Required in any fixed-wing airplane other than single-place
 Mounting to be as far aft as practical
 Battery replacement required by battery expiration date or after 1 hour of use
 Battery expiration date placard on ELT & in aircraft records
 Annual test for proper installation, battery corrosion, control operation, radiated signal
 FCC notice disallows sale of TSO C91 and C91a units (121.5 MHz) after about May 9, 2018
 Would become effective after publishing in Federal Register
 Has not been published yet
 FAA says no; asks FCC to rescind notice
 121.5 MHz units still allowed to be used
 ADS-B Out requirements- §91.225 & §91.227
 Mandatory Jan 1, 2020 in Mode C areas
 TSO’d equipment required for TC’d aircraft
 Mode S Extended Squitter- above 18K altitude- 1090 MHz
 UAT- up to 18K altitude- 978 MHz
 TSO not req’d for experimentals (ELSA)
 No requirements for periodic retesting
 One hour after a flight, go to the FAA’s website and request a Public ADS-B Performance Report
(PAPR).
 ADS-B In requirements
 Not required by FAA
 Provides display of traffic, weather, etc.
 FAA Maintenance Requirements
 Requirements for standard aircraft do not apply to experimentals (but are recommended)- §43.1(b)
 FAA Inspection Requirements
 Inspection required to scope & detail of Appendix D to 43- Operating Limitations
 Placards & markings required to be installed- §91.9 & Operating Limitations (sometimes)
 System-essential controls must be in good condition, be securely mounted, be clearly marked, &
provide for ease of operation- Operating Limitations (sometimes)
 Annual condition inspection by A&P, LSRM, or LSRI- Operating Limitations
 Logbook entry required by person doing annual condition inspection- Operating Limitations
 Requirements for LSRI Certificate
 Applicant requirements- §65.107
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 Must be at least 18 years of age
 Must be able to read, speak, & write English
 Must demonstrate the skill to determine whether a light-sport aircraft is in a condition for
safe operation
 Must be a U.S. citizen or permanent resident
 Must complete a 16-hour training course for the class of aircraft you own or plan to own
 Applicant must submit an application- §65.11
 Drug/alcohol offenses may result in certificate denial, suspension, or revocation- §65.12
 Address change notification required within 30 days- §65.21
 Certificate required to be kept in work area & presented to FAA, NTSB, or law enforcement officers
on request- §65.105
Module 3- Theory of Flight
 Our discussion will be limited to the depth applicable to the LSRI
 Limited to conventional wing-in-front, tail-in-back airplanes
 FMI: Pilot’s Handbook of Aeronautical Knowledge-- available in print or on Web
 Topics
 Air & the earth’s atmosphere
 Newton’s Laws of Motion
 The four forces on an airplane in flight
 Aircraft control
 Aircraft stability
 Load factors in maneuvers
 Control surface flutter
 Air & the earth’s atmosphere
 Air
 Is a fluid
 Has mass & weight
 Is compressible
 Has pressure, temperature, & density, all of which are interrelated
 When altitude, temperature, or humidity increase, air density decreases (“density altitude”
increases)
 Newton’s Laws of Motion
 1- A body at rest tends to stay at rest; a body in motion tends to stay moving in the same direction at
the same speed
 2- It takes force to accelerate an object or change its direction of motion
 3- For every action, there is an equal & opposite reaction
 The four forces on an airplane in flight
 Lift
 Weight
 Thrust
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 Drag
 Simplistically:
 In level flight at a constant airspeed
 Thrust & drag are equal
 Lift & weight are equal
 If thrust & drag become unequal, the airplane accelerates or decelerates
 If lift & weight become unequal, the airplane will either climb or descend
 Lift
 Produced by moving an airfoil through the air
 A wing is an airfoil section extended in the third dimension
 Planform (view from the top) may be rectangular, tapered, elliptical, swept, or other shapes
 Two effects at work
 Bernoulli Effect
 Upper camber is a longer path- causes lower pressure on the top surface
 Angle of attack
 Inclination of airfoil to airstream- causes higher pressure on the bottom surface
 Cutting through a lot of unnecessary complication:
 Both effects cause air behind the wing to be accelerated downward, thereby
(according to Newton’s third law) producing an upward force on the wing (lift)
 Airfoil pressure
distribution
 For positive angles of attack
 High on bottom
 Low on top
 Forces on an moving airfoil
 Lift increases with angle of attack (at the same airspeed)
 Center of pressure changes
 Airfoil is inherently unstable
 Horizontal tail is needed for control
 Aircraft CG must be kept well forward of CP
 Stall- at a certain angle of attack:
 Airflow abruptly separates from top wing
 Lift abruptly decreases
 Decreases when air becomes less dense (when density altitude increases)
 At higher altitudes
 At hotter temperatures
 At higher relative humidity
 Drag
 Induced drag
 Created as a result of the wing producing lift
 Parasite drag
 Drag due to the shape & surface finish of the fuselage, struts, landing gear, etc
 Drag, like lift, decreases when the air is less dense (when “density altitude” increases)
 Weight
 Can be considered to act through the aircraft center of gravity
 Can also be considered to include the effects of higher G-loads during maneuvers
 Center of gravity location is very important for aircraft control & stability
 Load factors in flight maneuvers
 Load factors- G’s
 “Limit” load factors for type certificated small aircraft- +3.8 G’s & -1.5 G’s
 Type certification tests at 150% of limit loads- “ultimate” load factor- +5.7 G’s & -2.25
G’s
 What limit loads was your ELSA designed and/or tested to??
 Load factors in flight maneuvers
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 Load increases during turns
 Load increases with increased angle of bank- 60 degrees=2 g’s (aerobatics)
 Load increases during dive recovery
 Thrust
 Produced by engine/propeller combination
 Increases with engine power
 Decreases when air is less dense (when density altitude increases)
 At higher altitudes
 At hotter temperatures
 At higher relative humidity
 Basic propeller theory
 Propeller blade is an airfoil, just like the wing
 Tips travel faster than hub
 Limit is speed of sound
 High-rpm engines must have shorter props-- thus the need for PSRUs
 Aircraft control & stability
 The Wright brothers’ key realization: the pilot must be able to control the airplane
 Stability
 The inherent quality of an airplane to automatically right itself if its flight is disturbed, with no pilot
input
 Two types of stability
 Static
 Dynamic
 It is highly desirable that an aircraft be both statically & dynamically stable
 Three axes around which we describe aircraft control & stability:
 Vertical axis- (directional control & stability)- rudder produces yaw changes
 Lateral axis- (longitudinal control & stability)- elevator produces pitch changes
 Longitudinal axis- (lateral control & stability)- ailerons produce roll changes
 Longitudinal stability- provided by CG fwd of center of lift & downward force at the tail
 Aft CG loading reduces longitudinal stability
 Reduced ability to trim the aircraft
 Poorer stall recovery
 Poorer spin recovery
 Tendency toward flat spins
 Lateral stability- provided by wing dihedral & keel area
 Directional stability- provided by aft fuselage & vertical fin area
 Control surface flutter
 High-frequency violent vibration of a control surface (aileron, elevator, rudder, trim tab)
 Can tear control surface off the airplane
 Aggravated by
 Looseness in hinges & actuating mechanisms
 Weight aft of the control surface hinge line
 Lack of torsional rigidity in control surface, wing, stabilizer, or vertical fin
 Can occur in slow-speed aircraft
For information, see the FAA Pilot’s Handbook of Aeronautical Knowledge
Module 4- Weight & Balance
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 Why is a current weight & balance important?
 It affects:
 Stability
 Stall characteristics
 Spin recovery
 Controllability
 Takeoff & climb performance
 Load factors on airframe during flight & landing
 Things change-- equipment, paint, etc
 Weight & balance form should include equipment list
 Two kinds
 Empty weight and balance report
 Someone actually weighs the aircraft (empty)
 Produces weight & balance report & equipment list for aircraft records
 Pre-flight weight & balance check
 Done by pilot before each flight
 Uses weight & balance report & adds people, fuel, baggage, etc.
 Assures that loaded weight and CG are within established limits
 Terminology
 Datum
 Imaginary location from which all longitudinal weight & balance measurements are referenced
 For some ELSAs, manufacturer provides data
 For other ELSAs, builder must choose
 Arm (or moment arm)
 Longitudinal distance from the datum to an item’s CG
 Moment
 An item’s weight multiplied by its arm
 Center of gravity
 Location where an object’s weight can be assumed to be concentrated
 If suspended from the CG, the object will balance
 Maximum weight (gross weight)
 Maximum authorized weight of the aircraft & its contents
 For some ELSAs, manufacturer provides data
 For other ELSAs, builder must choose
 Empty weight
 Weight of airframe, powerplant, required equipment, optional equipment, fixed ballast, full engine
coolant, full hydraulic fluid, full oil, & residual fuel
 Useful load
 Maximum weight minus empty weight
 Generally consists of pilot, passengers, baggage, & fuel
 Operating CG range
 Allowable CGs between forward & aft CG limits
 Mean aerodynamic chord (MAC)
 A parameter related to the wing design
 For an un-tapered non-swept wing, it is simply the length of the wing chord
 For a tapered or swept wing, it is the average value of the wing chord
 Operating CG ranges are sometimes expressed as percentages of the mean aerodynamic chord
 Why is MAC important?
 Good longitudinal control, stability, & stall/spin characteristics can be related to CG location
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as a percent of MAC
 Rules of thumb:
 Most aft CG location-- forward of about 30% MAC- prevents flat spins
 Most forward CG location-- about 20% MAC– provides enough elevator power
required to rotate for takeoff & flare for landing
 Weighing points
 Locations at which scales are placed under the aircraft for weighing
 Most often the landing gear, but may be jack points or other locations
 Minimum fuel
 Minimum safe amount of fuel for flight. Used in most-forward or most-aft CG computations
 1/12 gallon per engine horsepower (METO)
 HP  2 = minimum fuel weight (lbs)
 Basic procedure
 Weigh the aircraft at each wheel
 Measure the arm of each wheel from the datum
 Multiply each wheel weight times its arm to get its moment
 Add all the wheel weights to get a total
 Add all the moments to get a total
 Divide total moment by total weight to get center of gravity (CG) location
 Inspection Requirements
 A current weight & balance form & equipment list must be available in the aircraft records
 New weight & balance is required for empty weight or CG changes of:
 More than 1 lb weight
 More than .05% MAC center of gravity difference
 Detailed Procedure
 Follow along using the weight & balance spreadsheet included with the course handouts.
 Calculate empty weight & CG
 Calculate most aft CG condition
 Beginning with aft-most item, maximize weights aft of the aft CG limit & minimize weights
forward of the aft CG limit. Stay within the weight limits for each item & within the gross weight
 Calculate most forward CG condition
 Beginning with forward-most item, maximize weights forward of the forward CG limit &
minimize weights aft of the forward CG limit
 Weight & balance example
 RANS S-6ES Coyote II taildragger
Module 5- General Inspection Procedures
 General workplace safety measures
 Solvents & fuel are extremely flammable
 No smoking in the vicinity of the aircraft
 Dispose of solvent, oil, or fuel-soaked rags in a fireproof container
 Use explosion-proof flashlights & trouble lights
 Do not use solvents or fuel around heaters, batteries, & other sources of heat or sparks
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 Keep a fire extinguisher serviced & handy
 Avoid contact with fuel, solvents, acids, alkali cleaners, or other liquids
 Use protective goggles, gloves, & clothing
 Provide plenty of ventilation
 Have water supply handy for washing eyes or body parts--seek medical attention if exposed
 Do not eat or keep food where hazardous materials are stored
 Check & follow all applicable restrictions & requirements for use & disposal of waste material
 Practice safe use of ladders or platforms
 Use only sturdy, well-maintained ladders or platforms
 Use only self-supporting ladders or platforms--do not rest ladder on aircraft
 Use an assistant to brace ladder
 Wear protective goggles, gloves, & clothing to protect hands, eyes, & other body parts from cuts,
bruises, dust, metal filings, or other injuries
 Hot engines or exhaust systems may cause burns--use gloves & protective clothing
 Use appropriate techniques or equipment when lifting heavy objects
 Note: this is not an exhaustive list of safety considerations-- you are responsible for your own safety
 The key to workplace safety: think about what you are doing beforehand, analyze the safety hazards,
and implement ways to minimize the risk
 Specific workplace safety hazards are identified throughout the course
 Non-Destructive Inspection
 Surface or internal defects can cause parts to fail
 Failure in many cases is via crack growth due to stress concentrations
 Visual inspection
 Oldest, most common form of NDI; approximately 80% of all NDI is visual
 May be enhanced by instruments
 Touch everything you look at!
 Procedure
 Tools needed- flashlight (LED), inspection mirror, 10x magnifying glass, flashlight,
borescopes, etc
 Have pad/pencil ready to record squawks
 Perform preliminary inspection for cleanliness, presence of foreign objects, deformed or
missing fasteners, security of parts, corrosion, & damage
 Provide adequate lighting
 Provide for your personal comfort
 Eliminate excessive noise levels
 Provide ease of access
 Clean the areas or surface of the parts to be inspected. Remove any contaminates
 Carefully inspect for discontinuities
 Document all discrepancies for analysis
 AC43.13-1B Chapter 13 is a personal minimums checklist--am I ready to perform this
inspection?
 Penetrant inspection procedure
 Visible & fluorescent
 Works on all metals
 Can find only surface defects, not subsurface defects
 Follow manufacturer’s instructions
 Magnetic particle inspection
 Works only on iron and steel
 Can find surface and subsurface defects
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 Requires special training & equipment
 Tapping inspection
 Used on composite laminates. bonded joints, & sandwich construction
 Work in a pattern, tapping with a coin or other tool. Marking the outline of hollow-sounding areas
with a marking pen
 Most often used tapping tool: a U.S. quarter dollar
 Corrosion Inspection
 What is corrosion?
 An electrical or chemical process that converts a metal into a metal compound
 Example: conversion of iron or steel into iron oxide (rust)
 Corrosion weakens aircraft parts & leads to failure
 Stress concentrations figure heavily
 Necessary conditions for corrosion
 Metal that tends to corrode (anode)
 Dissimilar metal with less tendency to corrode (cathode)
 Continuous conductive liquid (electrolyte)
 Electrical contact between the anode & cathode
 Eliminating any one of these will stop corrosion
 Factors that influence corrosion
 Type of metal
 Magnesium corrodes easily
 Stainless steel doesn’t corrode easily
 Pure aluminum is less susceptible than alloyed aluminum
 2024 alloy is often “Alclad”-- thin, pure aluminum outer layer
 6061 allow is less susceptible than bare 2024, but 2024 is available with Alclad; 6061
is not. Anodizing improves corrosion resistance
 Heat treatment & grain structure
 Presence of a dissimilar, less corrodible metal
 Temperature- higher means more corrosion
 Type of electrolyte
 Acids (low pH) or alkalis (high pH)
 Earth’s atmosphere--oxygen & water vapor
 Salt water
 Foreign materials dissolved in water
 Dirt
 Engine exhaust products
 Availability of oxygen
 Presence of biological organisms
 Mechanical stress on the corroding metal
 Manufacturing processes can leave residual stresses
 Time of exposure to the corrosive environment
 Graphite pencil marks on airplane parts!
 Some types of corrosion- listed in AC 43.13-1B
 General surface corrosion
 Pitting corrosion
 Crevice corrosion
 Active/passive cells
 Filiform corrosion
 Intergranular corrosion
 Exfoliation corrosion
 Galvanic corrosion
 Stress corrosion cracking
 Fatigue corrosion
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 Fretting corrosion
 Visual inspection for corrosion
 Inspect exhaust trail areas
 Paint for damage
 Under fairings
 Around rivet heads
 In skin crevices
 Inspect battery compartment
 Electrolyte spillage
 Corrosion
 Condition of protective paint
 Areas around battery vent
 Inspect bilge areas
 Especially if operating in salt water
 Inspect landing gear area
 Wheels, brakes, axle interiors, attaching hardware
 Inspect airframe structure
 External skin areas & around fasteners
 Lap joints for bulging skin surface
 Inside surfaces of skins for pitting corrosion
 Bulges in fabric covering over structural members
 Composite skins for corrosion of attachment fasteners
 Inspect control surface hinges
 Lubricate them to prevent fretting corrosion
 Inspect water entrapment areas
 Areas around drain holes
 Ensure drain holes are open
 Inspect engine installation
 Engine cylinders & case for damage to finish & corrosion
 Radiator cooling cores for corrosion
 Inspect electrical areas
 Switches, circuit breakers, connectors for evidence of moisture & corrosive attack
 Inspect control cables
 External surfaces for corrosion
 If corrosion is found, check internal strands
 Remove external corrosion & apply preservative
 Inspect fuel tanks
Module 6- Aircraft Hardware
 Inspection of aircraft hardware includes:
 Recognizing it
 Judging its suitability for the installation
 Determining that it is installed properly
 Inspecting its condition
 Use of non-aircraft hardware—is it acceptable?
 Aircraft hardware is recommended
 Use what the manufacturer specifies
 You as an LSRI must decide if the aircraft is in a condition for safe operation using non-aircraft
hardware
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 Rivets
 Type
 Driven (set with rivet gun/bucking bar or squeezer)
 Aluminum- 2117-T4 “AD” rivet
 Other aluminum alloys not generally used in ELSAs
 Brass
 Blind (set with Pop-rivet-type tool)
 Aluminum
 Steel- tin plated
 Stainless steel (CRES)
 Driven rivets
 Universal head
 AN470 (MS20470)
 Countersunk head
 100 degree
 AN426 (MS20426)
 Round head
 AN430
 Specialty rivets
 Brake lining rivet
 Blind rivets
 Commercial quality
 Pop rivets, Avex rivets, etc
 Not considered as good as driven rivets
 Stems are hollow
 Often have lower strength
 Tendency to loosen in service
 Often used for structural purposes in ELSAs
 Aircraft quality
 Cherry, Cherrylock, CherryMax
 Stem is solid
 Driven rivet Material- head markings
 Dimple in the head indicates a 2117-T4 “AD” structural rivet
 For other head markings, see AC 43.13-1B
 Inspection of rivets
 Heads flat against part
 Adequate grip
 Well-formed tail
 Evidence of correct hole size
 Good sheet clamp-up
 Freedom from corrosion
 Screws
 Type
 Machine screw vs. self-tapping screw
 Structural vs. non-structural
 Head style
 Truss head vs. flat countersunk head
 Material
 Cad-plated steel
 Stainless steel (CRES)
 Brass
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 Machine screws
 Structural
 AN525- truss head
 AN509- flat head
 125,000 psi strength
 Non-structural
 AN526- truss head
 AN507- flat head
 AN515- round head
 55,000 psi strength
 Self-tapping screws
 Available in truss head or flat countersunk head
 Type A is for self-tapping into metal
 Type B is for threading into sheet metal clip nuts (“Tinnerman” nuts)
 Inspection of screws
 Structural applications
 Structural screws used
 Proper grip- no threads in bearing--use up to 1/8” of washers if necessary
 At least 1 full thread protruding from any self-locking nut
 Looseness
 Evidence of proper hole size
 Freedom from corrosion
 Bolts
 Type & material
 Indicated by head marking
 AN (often superceded by MS)
 NAS
 Cadmium-plated steel
 Stainless steel (CRES)
 Strength- cad-plated steel
 AN- 125,000 psi
 Some NAS- 160,000 psi
 Bolt features
 Hole for safety
 Diameter- 3/16” - 1-1/4”
 Length & grip
 Thread- U.S.
 National Fine (NF)
 National Coarse (NC)
 Inspection of bolts
 Heads should be up, forward, & outboard
 One full thread protruding from any self-locking nut
 Proper torque
 Freedom from corrosion
 No threads in bearing
 Nuts
 Type
 Locknuts, non-selflocking nuts, captive nuts
 Most aircraft applications require safetying
 Material
 Steel, stainless steel (CRES), or brass
 Finish
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 Cadmium plating, silver plating, black oxide
 Non-selflocking nuts
 Plain nuts
 Jam nuts on control rods
 Castellated nuts
 Use with cotter pins or safety pins
 May be used on bolts “subject to rotation”
 Locknuts
 Use locknuts only on bolts not “subject to rotation”
 Minimum of 1 full thread protruding from nut
 Nylon-insert (“Nylock”)
 Use only below 250F
 All metal- may be used in high-heat areas
 Cadmium-plated- to 450F
 Silver-plated- to 1400F
 Inspection of nuts
 Proper torque
 All castellated nuts have cotter pins
 No cotter pins reused
 Locknuts used only where appropriate
 Only on bolts not subject to rotation
 All-metal locknuts used in high heat areas
 Freedom from corrosion
 Torquing of Nuts, Bolts, & Screws
 What is torque?-- a twisting force applied through a lever arm
 Torque (in-lbs) = Arm Length (in) x Force (lbs)
 Metric torque measured in newton-meters
 Torquing procedure
 Torque wrenches
 Beam type
 Dial type
 Click type
 Electronic digital type
 Calibrate torque wrenches once a year or if dropped
 Whenever possible, apply torque to the nut, not the bolt
 Add friction drag to recommended torque values (especially with self-locking nuts)
 Threads should be clean & dry, unless otherwise specified by the manufacturer
 Use steady even pull
 When installing a castle nut, start alignment with cotter pin hole at min specified torque
 AC43.13-1B Table 7-1 lists default torque values
 Washers
 Type
 Plain washers
 Lock washers
 Special washers
 Material
 Cadmium-plated steel
 Stainless steel (CRES)
 Plain washers
 AN960- general purpose washer- thick or thin
 AN970- large diameter- originally developed to prevent crushing when bolting to wood
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 Cad-plated steel recommended for contact with aluminum or magnesium
 Special washers
 Tinnerman countersunk washers
 Nylon washers- prevents marring of paint
 Finishing washers- for upholstery attachment
 Lockwashers
 AN935- split ring type
 AN936A & B- star washers- internal & external
 Do not use lock washers
 In primary or secondary structure
 In areas exposed to airflow
 In areas where frequent removal is required
 Use a plain washer under a lock washer to prevent gouging of the base material
 Inspection of washers
 Pins
 Washers are present when needed
 Excessive washer stackup is not used to substitute for bolts/screws too long
 Cad-plated washers are used in contact with aluminum or magnesium
 Freedom from corrosion
 Types
 Clevis pins
 Cotter pins
 Safety pins
 Roll pins
 Materials
 Cadmium-plated steel
 Stainless steel (CRES)
 Inspection of pins
 All clevis pins have a washer & a cotter pin or safety pin
 Clevis pins should not be used on primary controls--use clevis bolt instead
 Roll pins secured with safety wire, where possible
 Quick-release pins have ball protruding from hole
 Safetying
 Definition: “Securing by various means any nut, bolt, turnbuckle etc., so that vibration will not cause it
to loosen during operation”
 Safety wire
 Stainless steel (CRES) used in most applications- .032” or .041” diameter
 Soft brass used on items that require emergency access
 Double wire twist- preferred
 Wire tightens when fastener tries to unscrew
 6-8 twists/in—too much may fail under vibration
 Must be tight after installation
 Ends bent in to prevent injury & safety hazards
 Single wire- acceptable for
 Screws in a closely spaced geometric pattern
 Difficult-to-reach areas
 Use largest wire size possible
 Cotter pins-
 Use largest diameter possible
 Bend ends down side and over top of nut & trim
 Bend ends completely around clevis pins & trim
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Module 7- Engine, Prop, Fuel, and Exhaust Systems
 A wide variety of engines, fuel systems, exhaust systems, & propeller installations are used in
ELSAs
 Engines
 Four-stroke
 Small Lycomings & Continentals
 Converted automobile engines
 Subaru, Volkswagen, Jabiru, & others
 Rotax 912, HKS, Verner, & others
 Two-stroke engines
 Rotax 447, 503, 582
 Hirth & others
 Cooling- air or water
 Ignition
 Dual or single
 Aircraft-type magnetos
 Battery
 Electronic
 Flywheel-type magneto- used on two-strokes
 Fuel
 Simple gravity-flow, single tank systems
 Complex systems with multiple tanks, high-pressure pumps, return lines, complex venting, etc
 Carburetion/fuel injection
 Aircraft-type float carburetors
 Throttle body injectors- Ellison, Posa, etc
 Electronic fuel injection
 Two-stroke carburetors- (1 or 2)- Bing, Mikuni, etc
 Lubricating oil systems
 Lycoming/Continental- wet sump
 Rotax 912- dry sump
 Two-stroke
 Mix oil with fuel
 Oil injection
 Exhaust system
 Lycoming/Continental-- straight stacks, crossover systems, mufflers
 Two-stroke- wide variety of mufflers, clamping arrangements, vibration isolators, etc
 Propeller speed reduction unit (PSRU)
 Lycoming/Continental- direct drive
 Auto conversions- direct drive or PSRU
 Two-strokes- most have PSRU
 Gear-driven
 Belt-driven
 Propellers
 Tractor or pusher
 Metal fixed-pitch
 Wood
 Fixed-pitch
 Ground adjustable
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 Composite
 Fixed-pitch
 Ground adjustable
 So, how can we cover all this territory in detail?
 Answer: we cannot
 Therefore, our primary inspection procedure is: follow the manufacturer’s instruction
 Beyond that, we can cover inspections
 That establish a general procedure
 That are common to a group of engines
 That address known problems
 Inspection of engine installation
 Follow along on Inspection Checklist included with the course handouts
Module 8- Airframe Inspection
 Topics
 Airframe construction methods & materials
 Wood
 Fabric covering
 Fiberglass & plastics
 Metal structure, welding, & brazing
 General airframe inspection
 Landing gear/brake system inspection
 Ballistic parachute inspection
 Wood Structures
 Aircraft-quality wood- Federal spec
 Sitka spruce-- the “standard”
 Fir, pine, hemlock, poplar, & cedar sometimes used
 Hardwoods used for compression blocks
 Plywood-- birch-faced or mahogany-faced
 Federal standards for grain, knots, pitch pockets, etc
 FAA-approved adhesives- Federal spec
 Synthetic resin
 Resorcinol-formaldehyde resin
 Urea-formaldehyde resin
 Phenol-formaldehyde resin
 Some specific epoxies
 FAA approved finishes- Federal spec
 Varnish- Federal Spec TT-V-109
 Some epoxy varnishes
 Visual inspection
 Plywood attachment plates- for bond line failures, nearby spar cracks
 Wing ribs- for looseness, damage
 Metal fittings- for looseness, cracks, warping
 Aileron/flap hinge brackets- for looseness, damage
 End grain- for checking, cracking
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 Plywood- for delamination (especially non-FAA-approved plywood)
 Finishes- for dryness, flaking, or discolored areas
 Entire structure- for water collection, bird nests, mold, decay
 Fabric Covering
 Types of fabric covering systems
 Heat-shrunk Dacron
 Glued-on blanket or pre-sewn envelopes
 Fabric is heat-shrunk with a household iron
 Various types of finishing systems fill the weave & provide UV protection
 Sails
 Dacron fabric stretched &/or laced in place
 Optional clear coating further fills the weave, prevents grease/oil staining, & provides some
UV protection
 Dacron fabric finishing systems
 Poly-Fiber- PVC-based coatings & adhesives
 Ceconite- non-tautening nitrate & butyrate dope
 Air-Tech, Loehle, & others- polyurethane-based coatings & adhesives
 Stewart Systems- waterborne coatings & adhesives
 All theoretically provide unlimited life if UV barrier is maintained
 Sail finishing systems
 Transparent color coats
 UV-absorbent topcoats
 Stits AO-100 UV- provides only about 25% of the UV protection of normal Poly-Fiber finish
 Sails exposed to the sun will degrade to an un-airworthy condition in a year or less, even
with the topcoat
 Other ELSA finishing systems
 Automotive paints
 Latex house paint
 ???
 Attachment to Wing Ribs
 Why is rib attachment needed?
 Negative pressure on top surface would cause ballooning- like a loose automobile
convertible top
 Ballooning changes airfoil shape- decreases lift & increases drag
 Riblacing (ribstitching)
 Traditional method
 Top & bottom surfaces are stitched together using special knots
 Blind rivets or screws attached to rib capstrip
 Fabric glued to capstrip--not recommended!
 Adhesive bonding to dacron is very limited
 Capstrip bonding area is small
 Adhesives fail most easily in peel
 Exposure to the sun may soften adhesive &/or eventually degrade it
 Sails- batten pockets
 Inspect fabric covering for
 General condition
 Damage
 Surface tapes coming loose
 Sewn seams loosening
 Drain holes clogged
 Finish peeling
 Tautness
 Too much can distort airframe
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 Too little can affect flight characteristics
 Strength & UV degradation
 Only FAA approved strength test is to pull test a sample- 40 lb/in min or 70% of original
 Strength clues
 Is the aircraft stored under a roof?
 On sails, look for color fading
 On Poly-Fiber, shine a strong light on upper wing fabric & look for light on inside of
the wing
 Fabric testers
 Maule- used on type-certificated aircraft
 Quicksilver- available from Lockwood Aviation, Leading Edge Airfoils, etc
 Rib attachment
 Rib lacing
 Inspect wing interior to see that laces are intact & tight
 Screws & clips
 Inspect wing interior to see that screws or clips are intact, tight, & corrosion-free
 Rib battens
 Inspect sewn sleeve seams for condition
 Inspect attachment of battens to wing spar
 Fiberglass & plastics
 Three general types
 Non-structural or lightly-loaded fiberglass laminates
 Cowlings, fairings, covers, sandwich panel facings
 Structural composites & sandwich construction
 Transparent plastics
 Inspect fiberglass, composites, & sandwich construction for
 Damage
 Finish failure
 Composites, like fabric, can be degraded by UV radiation from the sun
 Evidence of distortion from the sun’s heat
 Especially for aircraft painted any other color than white
 Inspect fiberglass, composites, & sandwich construction for
 Evidence of delamination within skin or between skin & sandwich core
 Tap with a special hammer or a coin to locate delaminations
 Security of previously repaired areas
 See AC43.13-1B Chapter 3 for acceptable repair methods
 Inspect transparent plastics for
 Distortions within pilot field of view
 Cracking
 Remember the effect of stress concentrations
 Metal structure, welding, & brazing
 Steel alloys used in ELSAs
 Low-carbon steels
 1010, 1018, 1020-- yield strength- 30,000 psi
 Weldable with oxy-acetylene, TIG, & MIG
 Chromium-molybdenum steels
 4130-- yield strength of 50,000 to 70,000 psi
 Weldable with oxy-acetylene, TIG, & MIG
 Stainless steel (301 or 304) or galvanized steel sheet used for firewall- .016” to .022” thick
 Aluminum alloys used in ELSAs
 2024-T3
 Yield strength of 40,000 psi
 Not ordinarily weldable
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 Medium corrosion resistance--greatly improved with “Alclad” pure aluminum outer layer
 6061-T6
 Yield strength of 35,000 psi
 Weldable
 Better corrosion resistance than bare 2024-T3
 Less expensive than 2024-T3
 5052-H32
 Very weldable
 Excellent corrosion resistance
 Often used for fuel tanks
 3003-O or -H14
 Low-strength-- almost pure aluminum
 Very formable & weldable
 Used for compound curved fairings
 Used for fuel line tubing
 7075
 High strength
 Now being used in landing gear spring struts
 More susceptible to corrosion
 Metal structure, welding, & brazing
 Truss structures
 Strength is in formation of triangles
 Welded steel
 Riveted or bolted aluminum
 Monococque structures
 Strength is in the skin
 Minimal inner structure to hold skin shape
 Generally riveted aluminum or composite
 Semi-monocoque structure
 Skin takes some of the load
 Internal structure includes longerons, bulkheads, stringers, ribs, spars, etc
 Generally riveted aluminum
 Welding & brazing methods
 Oxy-acetylene
 Oxygen & acetylene are mixed in a torch & burned
 Steel rod fed in manually
 Useful on low-carbon & 4130 steel
 Tungsten Inert Gas (TIG)
 Electric arc between a torch & the workpiece
 Argon or helium prevents oxidation in weld area
 Rod fed in manually
 Useful on steel, stainless steel, & aluminum
 Brazing
 Used on steel
 Uses oxy-acetylene torch
 Base material is not melted
 Fluxed bronze rod “wets” the steel to form the joint
 Not as strong as welding
 Inspect welded tube structures for
 Bends (even slight)
 Evidence of overstress
 Bulges or dents
 Cracks in paint
 Cracks
 Appearance of weld beads
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 Corrosion
 Inspect riveted aluminum structures for
 Evidence of overstress
 Bends or creases
 Loose or popped rivets
 Cracks in skins
 Corrosion
 Inspect all metal structures for
 Repairs that might lead to control surface flutter
 Weight changes aft of the hinge line- too many coats of paint
 Looseness of trim tab or its operating mechanism
 General airframe inspection
 Follow along on Inspection Checklist included with the course handouts
Module 9- Instrumentation, Electrical, and Avionics Systems
 Hey, my aircraft doesn’t have some of the normal aircraft instruments & equip--is that OK?
 Answer, per Operating Limitations & FAR 91.205
 No requirements for day/VFR
 Requirements for night/VFR
 Airspeed, altimeter, mag compass, tach, oil temp/press, coolant temp, position lights,
anticollision light, seat belts, shoulder harnesses, gear position indicator, spare fuses, ELT
 Flotation gear & pyro signaling device, if flown for hire over water. Landing light if flown for
hire.
 Other requirements for IFR
 Installed instruments must be maintained per FAR 91
 Instrumentation Systems
 Pitot-static instruments
 Electrical instruments
 Engine instruments
 Other instruments
 Magnetic compass
 Fuel gauge(s)
 Flap position indicator
 Trim position indicator
 Outside air temperature
 Clock
 Instrumentation system inspection
 Follow along on Inspection Checklist included with the course handouts
 Electrical System
 Electrical system consists of:
 Battery
 Battery charging system
 Wiring
 Grounding & bonding straps
 Circuit protection devices- breakers/fuses
 Switches & relays
 Electrical devices
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 Batteries found in ELSAs
 Lead-acid batteries
 Unsealed
 Aircraft
 Motorcycle
 Battery box with forced air circulation & drain lines recommended in enclosed
locations
 Sealed- “recombinant gas”- ex: Odyssey
 Lead/acid batteries are heavy & require proper structural support
 Lithium batteries- example: EarthX
 Require a battery management system
 Battery inspection
 Unsealed for proper electrolyte level
 All batteries for proper state of charge
 Corrosion of battery terminals, battery box, or nearby aircraft structure
 Unsealed- battery box vent & drain lines open
 Proper structural support
 Terminal insulation on battery & other high-current wires
 Battery charging systems found in ELSAs
 Generator & regulator
 Alternator & regulator
 “Charging coils” in 2-stroke engines
 Essentially a permanent-magnet alternator & regulator
 Wind generator
 Solar panel
 Plug-in-the-wall battery charger
 Inspect charging system components for
 Condition & security
 Signs of overheating
 Cracks, wear, proper tension of drive belts
 Wiring
 Authentic aircraft wire is recommended
 MIL-W-22759- current std- Teflon insulation
 Better insulation
 More strands- better vibration resistance
 Tin-plated wire strands- less corrosion
 Wire size & circuit protection
 Each electrical device uses a certain current
 Each wire size has a max rated current
 Circuit breaker/fuse
 Sized to max current
 Protects downstream wire from overheating
 Inspect wiring for
 Correct size & type for the application
 Condition of insulation, conductors, shielding, terminations
 Evidence of overheating
 Proper routing & supporting
 To eliminate chafing, vibration damage, & fouling of controls--min of 1/2” clearance
 Provide slack where necessary--example: rudder light wiring
 Proper routing & supporting
 Away from high-temperature devices
 Above & with minimum 2” separation from any flammable liquid line or fuel tank-- 6”
separation recommended
 Separating EMI-sensitive wiring
 Observing minimum bend radius requirements
 Security of crimp-on terminals
 Pull test suspect terminals
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 Use of tie straps
 Tie straps meeting MS17821 or MS17822 are recommended
 Use in areas where temperature is less than 120C (248F)
 Don’t use in high-vibration areas
 Use UV-resistant tie straps where UV degradation could occur
 Wires (or any other control, hose, etc) should not be tie-wrapped directly to structure
 Inspect grounding & bonding straps
 Condition & security
 Engine-to-airframe ground strap is especially important--bad connection can cause
heavy starter current to be carried by small-gauge wiring
 Inspect circuit breakers, fuseholders, & switches for
 Condition & security
 Proper current rating considering downstream wire size
 Proper placarding for function & operation
 Availability of spare fuses, where fuses are used
 Inspect electrical devices for
 Condition & security
 Perform electrical system operational test
 Apply electric power
 Test each switch, circuit breaker, & electrical device for proper operation
 Avionics Installation
 Avionics likely to be installed in ELSAs
 VHF communications radio
 Portable or in panel
 GPS receiver
 Portable or in panel
 Radar transponder & altitude encoder
 Intercom
 Emergency locator transmitter (ELT)
 ADS-B In and Out equipment
 Inspect avionics installations for
 Condition & security of equipment, cabling, antennas, circuit breakers, switches, &
microphone/headphone jacks
 Placards & marking for function & operation
 Time of last transponder/encoder/static system test per FAR 91.411 or 91.413-- required every 24
months
 Condition, security, & proper direction of mounting
 Proper operation of crash sensor
 Battery area corrosion
 Approved & unexpired ELT batteries (2)
 Presence of sufficient radiated signal
 Use a low-quality AM radio 6” from antenna
 Perform test within first 5 minutes of the hour
Module 10- Flight Control Systems
 Topics
 Types of flight control systems
 Rigging
 Inspection procedures
 Primary flight controls
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 Pitch- control stick operates elevators
 Roll- control stick operates ailerons
 Yaw- rudder pedals operate rudder
 Secondary controls
 Flaps or flaperons
 Trim- pitch, roll, &/or yaw
 Types of control mechanisms
 Pushrod
 Pushrods with spherical rod ends or clevises, bellcranks, torque tubes
 Control cable
 Cables, turnbuckles, bellcranks, pulleys
 Push-pull cable
 Heavy-duty Teleflex or Morse cables sometimes used for primary controls
 Bowden-type “choke” cables- primarily for secondary controls
 Control cable hardware
 Cable (wire rope)
 Types
 Non-flexible- 1x7, 1x19
 Flexible- 7x7, 7x19
 Material
 Galvanized steel
 Stainless steel (CRES)
 Nylon coated CRES
 Diameters likely used in ELSAs
 1/16”- breaking strength 480 lbs
 3/32”- breaking strength 1000 lbs galvanized steel; 920 pounds CRES
 1/8”- breaking strength 2000 lbs galvanized steel; 1760 lbs CRES
 Terminations
 Swaged
 Thimble with Nicopress sleeve
 Control cable terminations
 Swaged
 Swaged using special roll-forming equipment
 Go gauge determines acceptable swage
 Slippage indicators recommended
 Nicopress sleeves
 Can be crimped on simple, relatively inexpensive equipment
 Go gauge or diameter measurement determines acceptable crimp
 Bare copper- used with galvanized cable
 Tin-plated copper- used with stainless cable
 Aluminum- not used for aircraft- low strength!
 Safetying turnbuckles
 Safety wire
 Single wrap- simplest- adequate for ELSA
 Single wrap spiral
 Double wrap
 Double wrap spiral
 MS21256 clips
 Rigging of control systems
 Control travels are important
 Too little-- not enough control ability (on landing or takeoff, for instance)
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 Too much-- can cause the airplane to enter flight attitudes it was not tested for
 Cable tension is important
 Too low-- not enough travel under airloads
 Too high--excessive friction & loading of system
 ELSA manufacturer “may” provide specs
 Control stops are recommended
 At the control & at the surface
 Rigging should cause control stop to be contacted just after surface stop
 Inspection of all control systems
 Move the control through its entire range of travel, checking for
 Proper travel & contact with control stops
 Interference or binding
 Excessive friction
 Proper lubrication
 Freedom of motion at bellcranks & pivot points
 Proper safetying on bolts subject to rotation
 Damage or corrosion
 Inspect pushrod & push-pull control systems for
 Adequate thread engagement of rod ends
 If present, use witness holes to verify
 If not, disassemble rod end, counting threads, and reassemble counting threads
 Approx 1.25 to 1.38 diameters is generally adequate engagement
 Presence & torquing of jam nuts
 Condition & looseness of spherical rod end bearings
 Use of AN-970 washer on spherical rod ends not captured on both sides by the bellcrank
 Free rotational play in spherical rod ends (desired)
 Damage, bending, or loose rivets on pushrods
 Inspection of control cable systems
 Inspect cables for
 Condition, wear, & corrosion
 Proper tension
 Kinks & twisting
 Slippage of swaged terminations
 Use of copper or tin-plated copper Nicopress sleeves
 Broken strands
 Run a cloth over the cable- don’t use your bare hand!
 Visually inspect suspect areas with magnifying glass
 Flex the cable in suspect areas
 One broken strand requires replacement!
 Inspect pulleys for
 Wear
 Alignment with cable
 Freedom of movement
 Pulley bracket condition
 Presence of cable guards
 Inspect fairleads for
 Wear
 3-degree maximum cable direction change
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 Inspect turnbuckles for
 Presence & condition of safety
 Safety wire
 MS clips
 Maximum 3 threads showing
 Inspection of all control systems
 Proper placards
 Control surfaces for repairs that might lead to flutter
 Weight changes aft of the hinge line
 Too many coats of paint
 Control surface balance weights for security
Module 11- Operational Checks and Completion
 Follow along on Inspection Checklist included with the course handouts
 A word about logbooks
 Every ELSA should have separate logbooks dedicated to maintenance and inspections
 Aircraft- the master maintenance log for the aircraft
 Engine- recommended because engines get swapped
 Propeller- recommended because props get swapped
 Maintenance operations on the aircraft, engine, or propeller should be logged in the appropriate
logbook
 Annual condition inspection should be logged in the aircraft logbook
 Complete the paperwork
 Enter the following in the aircraft logbook (see wording in Operating Limitations):
“[Date & aircraft total time] I certify that this aircraft has been inspected on [insert date] in accordance
with the scope & detail of appendix D to part 43, & was found to be in a condition for safe operation.
[Your signature & LSRI Repairman certificate number]”
 Important notes:
 Once the annual condition inspection is begun, the aircraft is considered to be un-airworthy
until the inspection is complete, all discrepancies have been corrected, and the logbook entry
made.
 No flights of any kind (including test flights) are allowed during the time the inspection is being
conducted.
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