S — Aircraft StructuresChapter 1 · 25 practice questions

Chapter 1: CARs and Regulations - Standard 566, 571, 573, Approved Data, Maintenance Release

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CARs and Regulations - Standard 566, 571, 573, Approved Data, Maintenance Release

Overview

This chapter covers the regulatory framework governing aircraft maintenance in Canada under the Canadian Aviation Regulations (CARs). It focuses on the standards that define how maintenance must be performed, recorded, and certified, as well as the classification of repairs and modifications. The key standards addressed are Standard 571 (Maintenance), Standard 573 (Approved Maintenance Organizations), and Standard 566 (Maintenance Control Systems). Understanding these regulations is essential for ensuring airworthiness and compliance during all maintenance activities.

Diagram — CARs and Regulations - Standard 566, 571, 573, Approved Data, Maintenance Release CARs Standards 566, 571, 573 — Maintenance Regulatory Framework APPROVED DATA (CAR 571.02, 571.06) Manufacturer's Recommendations (TC Approved Manuals) Service Bulletins & Airworthiness Directives (ADs) TC Approved Repair/Mod Data (STC, DAO, 571.06) MAINTENANCE ACTIONS (Standard 571 — Maintenance) Repair Classification Minor / Major (571.06, 571.07) Modification Classification (571.06, 571.07) Scheduled / Unscheduled Insp. (571.02, 571.04) Parts Installation (571.08) MAINTENANCE RELEASE (CAR 571.10 — Certification) MCS — Std 566 Maintenance Control System AMO — Std 573 Approved Maintenance Org. Légende: Approved Data Maintenance Actions Release

Key Concepts

Maintenance Standards and Data Requirements (Standard 571.02)

Standard 571 maintenance map Standard 571 Map — Maintenance System 1. DATA APPROVED CTS, ACR, TCDS ACCEPTABLE AC 43.13, standards Major → approved data Minor → acceptable data Conflict → aircraft manufacturer takes precedence over engine/equipment 2. QUALIFICATION (571.02) Standard priority: 1. Aircraft manufacturer (always first) 2. Engine/propeller/equipment manufacturer 3. Standard industry practices (AC 43.13, TC, foreign authorities) Personnel: qualification standards or training required (571.02(3)) 3. RECORDING (571.03) Mandatory elements: • Product identification (aircraft, engine) • Description of work performed • Reference to standards used • Date, name and license number of AME • Defects found during disassembly • Partial work (precise location) ✗ Repair cost NOT required 4. SPECIALIZED MAINT. (571.04) WELDING Primary structure NDT Non-destructive testing ⚠ Requirement: AMO with appropriate category. Generic AME license insufficient 5. USED PARTS (571.08) ✅ In serviceable condition ✅ Conforms to its type design ✗ Cost / paint / origin are not requirements 6. RELEASE (571.10 / 571.11) Certifies: maintenance conforms to standards Aircraft ready for return to service ✗ Work authorization / defect list not required in the release 7. MAINTENANCE UNDER AMO CONTROL (571.05 / 573.02) Part IV aircraft (flight schools) and Part VII (commercial operations): maintenance must be performed under the control of an AMO approved under article 573.02 Arrangement 573.11 → AMO signs Flow: Data → Classification → Execution → Recording → Release Standard 571 — CARs — Transport Canada — AME Training

Manufacturer's Recommendations as Primary Standard

Standard 571.02 establishes that all maintenance must be performed in accordance with the aircraft manufacturer's recommended practices. When the aircraft manufacturer's recommendations conflict with those of an engine, propeller, or appliance manufacturer, the aircraft manufacturer's recommendations take precedence. This hierarchy ensures that airframe integrity and overall aircraft compatibility are prioritized over component-specific guidance.

Use of Alternative Standards

When the manufacturer has not published specific recommendations for a task, the AME must use standard industry practices. These include:

  • Methods published by Transport Canada
  • Methods published by a foreign civil aviation authority with which Canada has an agreement
  • Methods published by the manufacturer of a similar product
  • Other generally accepted industry practices

Advisory Circular AC 43.13 (issued by the FAA) is recognized as a standard industry practice and may be used when manufacturer data is unavailable.

Personnel Qualification Requirements

Standard 571.02(3) requires that persons performing specified tasks meet the applicable personnel qualification or training standards. This ensures that complex or safety-critical tasks are performed only by individuals with appropriate training and certification.

Maintenance Recording Requirements (Standard 571.03)

Required Elements of a Maintenance Record Entry

Standard 571.03 specifies the information that must be recorded for each maintenance task:

  • Product identification (aircraft registration, component part number, serial number)
  • Description of work performed
  • Reference to standards used (if other than manufacturer's recommended practice)
  • Date of maintenance
  • Employee identification (AME license number or personal identifier)
  • Details of defects found during disassembly

Documentation of Defects Found During Disassembly

Standard 571.03(f) specifically requires that when disassembly is required during maintenance, a general description of any defect found prior to re-assembly must be recorded. This ensures that hidden damage is documented and traceable.

Recording of Alternative Standards Used

Standard 571.03(c) requires that when a standard other than the manufacturer's recommended practice is used, the reference to that standard must be recorded. This provides traceability and accountability for the maintenance performed.

Documentation of Partially Completed Work

Standard 571.03(g) requires that when a task is partially completed, a general description of any outstanding work must be recorded, including the specific location of any parts or systems that have been disturbed. This prevents incomplete work from being forgotten and ensures proper completion.

Information NOT Required in Maintenance Records

The cost of the repair is not a required element in the technical maintenance record. The focus is on technical accuracy and traceability, not financial information.

Classification of Repairs and Modifications (Standard 571.06)

Structural repair/modification data decision Data for Structural Repair/Modification CLASSIFICATION (Standard 571.06) Minor Repair Negligible effect on airworthiness Major Repair Non-negligible effect: weight, balance, structure Major Modification Alteration: weight, balance, strength, performance, powerplant, flight characteristics DATA TYPES Approved Data • STC • RDA • TCDS sheets Formal approval of type design Acceptable Data • TC advisory docs • FAA AC 43.13-1B/2A • Industry standards Means of compliance without formal approval KEY REGULATORY REQUIREMENTS 571.02 — Manufacturer priority 1. Aircraft manufacturer (prevails) 2. Engine/propeller/equip. mfr. 3. Standard industry practices 571.03 — Recording • Product identification, description • Standard reference, date, employee • Defects, partial work 571.10 — Maintenance release • Certifies compliance with standards • Ready for return to service • Required for ALL maintenance 571.04/571.05 — AMO role • Primary struct. welding, NDT • Part IV/VII: AMO control 571.08 — Used parts • Service condition • Conforms to type design Standard 625 — Elementary work • Tires, lubrication, oil changes • Maintenance release required Major modification → approved data Minor repair → acceptable data
Standard 571 — Repair/Modification Classification Standard 571 — Repair / Modification Classification START Nature of intervention? REPAIR MODIFICATION Major or Minor? Major or Minor? MAJOR MINOR MAJOR MINOR APPROVED DATA (STC / CTS) Mandatory ACCEPTABLE DATA (AC 43.13 / Man.) Sufficient APPROVED DATA (CTS / STC) Mandatory ACCEPTABLE DATA (AC / Ind. Std.) Sufficient SIGNATURE AME Cat. M/S + Specific ACA (571.11) SIGNATURE Licensed AME Appr. Category (571.10) SIGNATURE AME Cat. M/S + Specific ACA (571.11) SIGNATURE Licensed AME Appr. Category (571.10) EDUCATIONAL NOTE All maintenance requires a release (571.10). Major Mod = Significant impact on airworthiness.

Major Repair Definition

A major repair is defined as a repair that has other than a negligible effect on:

  • Weight
  • Balance
  • Structural strength
  • Performance
  • Powerplant operation
  • Flight characteristics
  • Environmental characteristics

The classification is based on the effect on airworthiness, not on cost, specific processes (such as welding), or the type of structure involved.

Major Modification Definition

A major modification is an alteration that has other than a negligible effect on the same characteristics listed above for major repairs. A change in color or other cosmetic alterations with negligible effect does not qualify as a major modification.

Approved Data vs. Acceptable Data

Standard 571.06 distinguishes between two categories of technical data:

Approved Data includes documents that have undergone a formal type design approval process:

  • Type Certificates (TC)
  • Supplemental Type Certificates (STC)
  • Repair Design Approvals (RDA)
  • Type Certificate Data Sheets (TCDS)

Acceptable Data includes documents that provide an acceptable means of compliance but have not undergone formal approval for a specific installation:

  • Advisory Circulars (e.g., FAA AC 43.13-1B, AC 43.13-2A)
  • Transport Canada advisory documents
  • Foreign airworthiness authority advisory documents (with which Canada has an agreement)

Application of Data Types

  • Major repairs and modifications require approved data (STC or RDA)
  • Minor repairs may use acceptable data (such as AC 43.13)
  • The AME can install a modification but cannot approve the design; design approval requires an STC or RDA

Maintenance Release Requirements (Standard 571.10)

Signature authority and release Signing Authority and Release WHO CAN SIGN TEA license category M or S with applicable certification authority OMA (573.11) for maintenance under arrangement Major repair Part VII: appropriate TEA license required WHEN TO SIGN After ALL maintenance (including minor repairs and elementary work) Compliance verification work performed per applicable standards Airworthiness confirmed product ready for return to service ON WHAT DATA APPROVED DATA CTS / ACR / TCDS required for major modifications ACCEPTABLE DATA AC 43.13, industry standards sufficient for minor repairs TECHNICAL RECORD ENTRIES (Standard 571.03) REQUIRED ELEMENTS • Product identification (aircraft, engine) • Description of work performed • Reference to standards used • Date of completion • Employee name and license number SPECIAL CASES • Defects found during disassembly (571.03(f)) — general description • Partially completed work (571.03(g)) — work in progress and location of displaced parts NOT REQUIRED ✗ Repair cost ✗ Work authorization ✗ Defect list Standards 566, 571, 573 of the Canadian Aviation Regulations (CARs) — TEA Training Transport Canada — Maintenance release (571.10) and signing authority (571.11)

Definition and Purpose

A maintenance release is the certification statement that maintenance has been performed correctly and the aeronautical product is fit for return to service. It is required for all maintenance performed, not just major repairs or modifications.

Required Elements of a Maintenance Release

The maintenance release must certify that:

  • The maintenance has been performed in accordance with applicable standards
  • The aeronautical product is ready for return to service

Authorization to Sign a Maintenance Release

For a major repair on a large aircraft operated under Part VII (commercial operations), the person signing the maintenance release must:

  • Hold the appropriate AME license category (e.g., M or S)
  • Have the applicable certification authority

The regulation focuses on the license and certification authority, not solely on whether the person performed the work.

Maintenance Release for Components Overhauled Outside an AMO

When maintenance is performed outside an AMO under a maintenance arrangement per CARs 573.11, the maintenance release must be issued by the AMO that has the arrangement. The AMO is responsible for the work performed under their control.

Specialized Maintenance Requirements (Standard 571.04)

Approved Maintenance Organization (AMO) Requirements

Specialized maintenance such as welding on primary structures and non-destructive testing (NDT) must be performed by an AMO with the appropriate category for that process. A generic AME license or non-aviation certification is not sufficient for these specialized tasks.

Maintenance Control for Commercial Operations (Standard 571.05)

AMO Control Requirement

Maintenance on aircraft operated under Part IV (flight training) or Part VII (commercial operations) must be performed under the control of an AMO approved pursuant to section 573.02. This ensures a higher level of oversight for commercial and training aircraft.

Elementary Work (Standard 625)

Elementary work vs specialized maintenance Elementary Work vs Specialized Maintenance Standards 625, 571.04, 571.06, 571.10 — RAC ELEMENTARY WORK Standard 625 — Simple tasks • Tire changes • Lubrication / greasing • Oil changes • Minor adjustments • Filter replacement Characteristics: • Negligible effect on airworthiness • No approved data required • No certification required (571.03) Certification: No maintenance release required — excluded task (Standard 625) Responsibility: The executing AME or AMO must follow good practices SPECIALIZED MAINTENANCE Standard 571.04 — Specialized processes • Welding on primary structure • Non-destructive testing (NDT) • Heat treatment • Certified aircraft painting • Structural composite repair Characteristics: • Potential impact on airworthiness • Requires specific qualification • Mandatory AMO supervision Certification: AMO with appropriate category required — generic AME license insufficient Responsibility: The AMO assumes responsibility for work under its control CRITERIA COMPARISON Airworthiness impact Elementary work: Negligible or no effect Specialized maintenance: Potential significant effect Data required Elementary: Acceptable data Specialized: Approved data Maintenance release (571.10) Elementary: Not required Specialized: Required — signing AMO Legal responsibility Elementary: Executing AME Specialized: Supervising AMO KEY RULE: An AME license is not sufficient for specialized work — an AMO with the appropriate category is mandatory (571.04) Elementary work is excluded from the maintenance release, but any other task requires certification (571.10)

Definition and Examples

Elementary work is defined in Standard 625 and includes simple tasks that do not require complex technical judgment:

  • Changing tires
  • Servicing (fluids, lubricants)
  • Minor adjustments
  • Simple inspections

Maintenance Release for Elementary Work

Even elementary work requires a maintenance release if it constitutes a maintenance action. For example, blending out a corrosion pit (even within allowable limits) is a maintenance task and requires a maintenance release.

Used Parts (Standard 571.08)

Requirements for Installation

When installing a used part on an aircraft, Standard 571.08 requires confirmation that:

  • The part is in a serviceable condition
  • The part conforms to its type design

These requirements ensure the part is airworthy. Cost, paint condition, or origin from a similar model are not primary regulatory requirements.

Important Regulations and Procedures

Hierarchy of Maintenance Data

Maintenance Data Hierarchy Flow Maintenance Data Hierarchy Standard 571.02 — Priority of Standards for Maintenance Performance 1. AIRCRAFT MANUFACTURER RECOMMENDATIONS Absolute priority — primary instructions priority 2. ENGINE, PROPELLER OR EQUIPMENT MANUFACTURER CONFLICT? Aircraft manufacturer prevails if no recommendation 3. STANDARD INDUSTRY PRACTICES Methods published by TC, foreign authorities, similar manufacturers acceptable data 4. ACCEPTABLE DATA — AC 43.13-1B / 43.13-2A FAA AC 43.13 — Acceptable means of compliance, without formal approval approved data 5. APPROVED DATA — STC / RDA Supplemental Type Certificate / Repair Design Approval MAJOR REPAIRS Require approved data (STC/RDA) LEGEND Priority (level 1) Applicable standards Specific requirement 571.02(3) — Qualifications Any person performing specific tasks must meet applicable qualification standards. 571.06 — Classification • Major mod.: effect other than negligible • Major repair: requires approved data • Minor repair: acceptable data 571.10 — Release All maintenance requires a maintenance release.
  1. Aircraft manufacturer's recommendations (primary)
  2. Engine/propeller/appliance manufacturer's recommendations (when compatible with aircraft manufacturer)
  3. Standard industry practices (when manufacturer data is unavailable)
  4. Acceptable data (advisory circulars, foreign authority documents)
  5. Approved data (STC, RDA) for major repairs/modifications

Documentation Flow for Maintenance Tasks

Maintenance Record and Documentation Flow Maintenance Task Recording Flow STEP 1 Identify the task and required data STEP 2 Verify manufacturer data (571.02) STEP 3 Choose acceptable data STEP 4 Record the standard used (571.03) STEP 5 Document disassembly defects and partial work STEP 6 Maintenance release (571.10) KEY REGULATORY REFERENCES Standard 571.02: Priority: aircraft manufacturer → engine/equipment manufacturer → standard industry practices (AC 43.13) Standard 571.03: Required entry: product identification, work description, standard reference, date, employee identification Standard 571.10: Maintenance release required for ALL maintenance — certification that the product is ready for return to service Key requirements: Disassembly defects (571.03(f)) • Partial work (571.03(g)) • Cost NOT required • Signature authority (571.11)
  1. Identify the task and required data
  2. Determine if manufacturer data exists
  3. If not, select appropriate acceptable data
  4. Record the standard used (if not manufacturer's)
  5. Document defects found during disassembly
  6. Record partially completed work details
  7. Complete maintenance release upon task completion

Classification Decision Tree

  • Does the alteration have more than negligible effect on airworthiness characteristics?
  • Yes → Major repair or major modification (requires approved data)
  • No → Minor repair or minor modification (may use acceptable data)

Common Relationships Between Concepts

Relationship Between Data Type and Repair Classification

  • Minor repairs typically use acceptable data (AC 43.13)
  • Major repairs require approved data (STC or RDA)
  • The AME can perform the installation but cannot approve the design for major modifications

Relationship Between Maintenance Type and Release Requirements

  • All maintenance requires a maintenance release
  • Elementary work requires a release if it is a maintenance action
  • The release certifies proper performance and return to service

Relationship Between AMO Control and Specialized Tasks

  • Welding on primary structures requires an AMO with appropriate category
  • NDT requires an AMO with appropriate category
  • Commercial operations require AMO control for all maintenance

Relationship Between Documentation and Traceability

  • Recording alternative standards ensures traceability
  • Documenting defects found during disassembly ensures hidden damage is tracked
  • Recording partially completed work prevents oversight
  • The maintenance release provides the final certification of airworthiness

Diagram

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