Maintenance Schedule Approval Policy and Procedures Manual

September 2026

Revision 4

TP 13094E
(09/2026)

Forward
1.0 Introduction
2.0 References and requirements
3.0 Background
4.0 Approved maintenance schedules
- 4.1 Application forms, fees and service standards
- 4.2 Application
5.0 Schedule development
6.0 Periodic verification of an approved maintenance schedule
7.0 Amendments to an approved maintenance schedule
- 7.1 Addition of tasks or reduction of intervals
- 7.2 Deletion of tasks and interval escalations
8.0 TCCA review and approval
9.0 Information management
10.0 Document history
11.0 Contact us
Appendix A — Maintenance schedule basis and revision status of source documents
1.0 Maintenance schedule basis
2.0 Revision status of source documents
- 2.1 Using a specific revision
- 2.2 Using latest revision

© His Majesty the King in Right of Canada, as represented by the Minister of Transport, 2026.

Permission is granted by the Department of Transport, Canada, to copy and/or reproduce the contents of this publication in whole or in part provided that full acknowledgment is given to the Department of Transport, Canada, and that the material be accurately reproduced. While use of this material has been authorized, the Department of Transport, Canada, shall not be responsible for the manner in which the information is presented, nor for any interpretations thereof.

It may become obsolete in whole or in part at any time without notice.

Cette publication est aussi disponible en français sous le titre: Manuel des politiques et procédures : Approbation du calendrier de maintenance

TP 13094E (RDIMS 21443460)

TP 13094F (RDIMS 21455176)

Cat No.: T52-4/285-2026E-PDF

ISBN: 978-0-662-85989-5

TC-1001769

Forward

This manual has been prepared for Transport Canada personnel and the aviation industry. It contains information regarding the development and approval of aircraft maintenance schedules to comply with section 605.86 of the Canadian Aviation Regulations (CARs) and associated Standard 625.

Revision 4:

Original signed by Stacey Mason

For

Jamie-Lee MacDermid
Executive Director,
Standards Branch
Civil Aviation Directorate
Transport Canada

1.0 Introduction

1.1 Purpose

(1) This Technical Publication (TP) manual sets out the policy and procedures for the development and approval of initial aircraft maintenance schedules, including their amendments, to comply with Canadian Aviation Regulation (CAR) 605.86 and associated Standard (STD) 625. This TP is referenced in STD 625 Appendix D as the manual to follow for aircraft maintenance schedule approvals.

1.2 Applicability

(1) This manual has been prepared for use by the aviation industry and Transport Canada Civil Aviation (TCCA) personnel.

(2) This manual applies to owners and operators of commercially operated small aircraft, other than balloons, any large aircraft, irrespective of commercial or non-commercial operation, pressurized turbine-powered aircraft and airships. It includes type certified and non-type certified aircraft.

1.3 Description of changes

(1) This document has been extensively edited and reformatted since the issuance of Revision 3; changes occur throughout.

2.0 References and requirements

2.1 Reference documents

(1) It is intended that the following reference materials be used in conjunction with this document:

Part I, Subpart 1 of the Canadian Aviation Regulations (CARs) — Interpretation
Part I, Subpart 4 of the CARs — Charges
Part IV, Subpart 6 of the CARs — Flight Training Units
Part V, Subpart 21 of the CARs — Approval of the Type Design or a Change to the Type Design of an Aeronautical Product
Part V, Subpart 71 of the CARs — Aircraft Maintenance Requirements
Part VI, Subpart 2 of the CARs — Operating and Flight Rules
Part VI, Subpart 3 of the CARs — Special Flight Operations
Part VI, Subpart 4 of the CARs — Private Operators
Part VI, Subpart 5 of the CARs — Aircraft Requirements
Part VII, Subpart 6 of the CARs — Aircraft Maintenance Requirements for Air Operators
Standard 426 of the CARs — Flight Training Units
Standard 571 of the CARs — Maintenance
Standard 623 of the CARs — Special Flight Operations
Standard 624.56 of the CARs — RVSM Requirements
Standard 625 of the CARs — Aircraft equipment and Maintenance Standard
Standard 726 of the CARs — Air Operator Maintenance
Technical Publication (TP) 1490 — Manual of all weather operations (Categories II and III)
TP 4711 — Air Operator Certification Manual
TP 6327 — Safety criteria for approval of extended range twin-engine operations (ETOPS)
Note: TP 6327 is being proposed to be amended by Notice of Proposed Amendment 2026-007 to reflect CARs amendment SOR/2025-226 and introduce the EDTO regime.
TP 12862 – How to Start a Flight Training Unit
TP 13850 — Scheduled Maintenance Instruction Development Processes
TP 14408 — Transport Canada Civil Aviation Guidelines: Maintenance Control Manual (MCM)
AC 507-001 — Special Certificate of Airworthiness – Limited
AC 507-002 — Certificate of Airworthiness
AC 571-025 — Maintenance of Emergency Locator Transmitters (ELTs)
AC 605-002 — Reliability Methods for Maintenance Schedule Amendment
AC 605-005 — Alternative Means of Compliance (AMOC) with Airworthiness Directives Process
Airworthiness Notice (AN) B041 — Piston Engine On-Condition Maintenance Program Requirements
AN B062 — Review of Maintenance Requirements of Skis and Wheel/Skis Installed on Small Aircraft
Airworthiness Manual Advisory (AMA) 571.101/1 — Reliability Monitoring Programs
Transport Canada form number 24-0055A — Small Aircraft Maintenance Schedule Approval
Transport Canada form number 24-0055B — Large Aircraft Maintenance Schedule Approval
Transport Canada form number 24-0055C — Maintenance Schedule Amendment Request

2.2 Cancelled documents

(1) Not applicable.

(2) By default, it is understood that the publication of a new issue of a document automatically renders any earlier issues of the same document null and void.

2.3 Definitions and abbreviations

(1) The following definitions are used in this document:

Aeronautical product: means an aircraft, aircraft engine, aircraft propeller or aircraft appliance or part, or a component part of any of those things.
Air time: means, with respect to keeping technical records, the time from the moment an aircraft leaves the surface until it comes into contact with the surface at the next point of landing.
Aircraft make and model: A distinct sub-set or variant of an aircraft type. Where the aircraft is type certified, the model designation referenced in the type certificate data sheet (TCDS). Where the aircraft is not type-certified, the model designation assigned by the manufacturer.
Aircraft type: means a classification of aircraft having similar design characteristics.
Airship: means a power-driven, lighter-than-air aircraft;
Airworthy: in respect of an aeronautical product, means in a fit and safe state for flight and in conformity with its type design.
Airworthiness Directive: means an instruction issued by the Minister or by a civil aviation authority responsible for an aeronautical product type design that mandates a maintenance or operation action to ensure that an aeronautical product conforms to its type design and is in a condition for safe operation.
Airworthiness Limitation: means a limitation applicable to an aeronautical product, in the form of a life limit or a maintenance task that is mandatory as a condition of the type certificate.
Appliance: means any instrument, mechanism, equipment, apparatus or accessory that is:
1. used, or intended to be used, in operating or controlling an aircraft in flight,
2. installed in or attached to, or intended to be installed in or attached to, the aircraft, and
3. not part of the airframe, engine or propeller of that aircraft.
Applicant: the aircraft owner, operator, or their representative, who is applying for a maintenance schedule approval.
Continuing Airworthiness: The set of processes by which an aircraft, engine, propeller or part complies with the applicable standards of airworthiness and remains in a condition for safe operation throughout its operating life.
Instructions for continued airworthiness: means instructions and information necessary for the continued airworthiness of the aeronautical product, which must be developed and/or referenced by the design approval holder in accordance with the applicable certification basis or standard.
Interval: means the period defined in STD 625 or in the approved aircraft maintenance schedule (in hours, cycles or calendar time) that a particular maintenance task repeats and is required to be completed.
Large aircraft: means an aeroplane having a maximum permissible take-off weight in excess of 5 700 kg (12,566 pounds) or a rotorcraft having a maximum permissible take-off weight in excess of 2 730 kg (6,018 pounds).
Maintenance Monitoring Program: a process meeting AMA 571.101/1 described and approved in an air operator Maintenance Control Manual (MCM) to allow specified changes to the air operator’s approved maintenance schedule as described in STD 625.86(11)(b), without prior approval from the Minister. Also known as Maintenance Development Program.
Maintenance Review Board Report: the recommendations of a program development group, which are submitted to the aviation regulatory authority's Maintenance Review Board (MRB) for approval and thereafter form an approved basis on which a new operator may establish an aircraft maintenance schedule. A Maintenance Review Board Report (MRBR) forms part of the instructions for continued airworthiness (ICA) for the aircraft, as the scheduled maintenance recommendation.
Maintenance Schedule: means a schedule required pursuant to section 605.86 for the performance of the inspections and other maintenance required by these Regulations.
Manufacturer’s recommendations: means the scheduled maintenance recommendations from the aeronautical product manufacturer which are found in the aeronautical product manufacturer’s Instructions for Continued Airworthiness (ICAs) or other documents such as servicing instructions and service bulletins or other equivalent documents.
Operating experience on type: refers to an operator’s operational, maintenance, reliability and performance monitoring experience obtained with a particular aircraft make and model.
Operator: in respect of an aircraft, means the person that has possession of the aircraft as owner, lessee or otherwise. For the purpose of this manual, operator also includes holders of an air operator certificate under CAR Part VII, flight training unit certificate under CAR 406 and private operator registration document under CAR 604.
Owner: in respect of an aircraft means the person who has legal custody and control of the aircraft;
Reliability: the probability that an item will perform a required function, under specified conditions, without failure, for a specified period (calendar, hours, or cycles).
Reliability data: Any data generated as a result of aircraft operations, monitoring, sampling and maintenance.
Reliability program: means a structured approach to selecting, collecting and analyzing reliability data, as described in an air operator’s Maintenance Control Manual, to ensure that an aircraft maintenance schedule remains effective, address required maintenance reliability monitoring elements related to Specific Approvals (SA) and for the purposes of supporting an amendment to an approved aircraft maintenance schedule.
Servicing: in respect of an aeronautical product, means cleaning, lubricating and the replenishment of fluids not requiring the disassembly of the product.
Schedule: a structured list of required tasks to be accomplished and the intervals between repetitions of tasks.
Specific Approval (SA): in alignment with the International Civil Aviation Organization (ICAO) terminology, the term “Specific Approval” replaces the term “Special Authorization” use in the Canadian Aviation Regulations (CARs).
Small Aircraft: means an aeroplane having a maximum permissible take-off weight of 5700 kg (12,566 pounds) or less, or a helicopter having a maximum permissible take-off weight of 2730 kg (6,018 pounds) or less.
Substantiating data: means relevant technical data for the scheduled maintenance of an aircraft required to support the aircraft’s continuing airworthiness, such as the aircraft, engine, propeller, appliance or part manufacturer or type design holder’s scheduled maintenance recommendations or maintenance data collected as part of operator experience on the specific aircraft type.
Task: means an action or set of actions intended to restore an item to, or maintain it in, an airworthy condition, including inspection to determine if the item is airworthy.
Tolerance: means the permissible variance associated with an interval at which the task is required to be accomplished.

(2) The following abbreviations are used in this document:

AC: Advisory Circular
AD: Airworthiness Directive
AMA: Airworthiness Manual Advisory
AWL: Airworthiness Limitation
CAR: Canadian Aviation Regulations
CAT: Category
EDTO: Extended Diversion Time Operations
ETOPS: Extended Range Twin-engine Operations
ICA: Instructions for Continued Airworthiness
MCM: Maintenance Control Manual
MMP: Maintenance Monitoring Program
MPD: Maintenance Planning Document
MRB: Maintenance Review Board
MRBR: Maintenance Review Board Report
OEM: Original Equipment Manufacturer
PMI: Principal Maintenance Inspector
POI: Principal Operations Inspector
RDA: Repair Design Approval
RVSM: Reduces Vertical Separation Minimum
SA: Specific Approval
SB: service bulletin
STC: Supplemental Type Certificate
STD: Standard
TCCA: Transport Canada Civil Aviation
TP: Technical Publication

3.0 Background

(1) Aircraft owners/operators are responsible to maintain their aircraft in accordance with a maintenance schedule that conforms to STD 625.86, as flying an aircraft that is not maintained in accordance with its maintenance schedule is a contravention under CAR 605.86.

(2) Furthermore, aircraft owners/operators are also responsible to ensure that all Airworthiness Limitations (AWLs) and Airworthiness Directives (ADs) applicable to their aircraft or other products installed on their aircraft are complied with, as flying an aircraft that is not maintained or does not meet the requirements of an AWL or AD is a contravention under CAR 605.84.

(3) Maintenance schedules contain the necessary information on what needs to be inspected and maintained, and when it needs to be accomplished. It also contains details such as overhauls, replacements, functional checks, operational checks, servicing, and other types of maintenance tasks.

(4) The maintenance schedule minimum requirements are outlined in STD 625 Appendices B, C and D. The following policies and procedures outline the development and approval of initial and amendments to aircraft maintenance schedules.

4.0 Approved maintenance schedules

(1) The following aircraft require a TCCA approved maintenance schedule:

Commercially operated small aircraft, other than balloons;
Any large aircraft, irrespective of commercial or non-commercial operation;
Pressurized turbine-powered aircraft; and
Airships.

(2) An aircraft owner/operator will apply to TCCA to request approval for an initial or amended maintenance schedule and demonstrate, through substantiating data, that their proposed schedule meets the requirements in STD 625 Appendix D.

(3) Maintenance schedule amendments are approved by TCCA, unless prior approval has been obtained to incorporate amendments via a Maintenance Monitoring Program (MMP) in accordance with STD 625.86(11)(b) and the MMP is approved in the air operator’s Maintenance Control Manual (MCM). See section 7.0 for amendments to approved maintenance schedules. See Advisory Circular (AC) 605-002 and Airworthiness Manual Advisory (AMA) 571.101/1 for more information on MMP.

4.1 Application forms, fees and service standards

(1) Application should be made utilizing the applicable form available on the Transport Canada Forms Catalogue website:

Small Aircraft Maintenance Schedule Approval form 24-0055A;
Large Aircraft Maintenance Schedule Approval form 24-0055B; and
Maintenance Schedule Amendment Request form 25-0055C.

(2) The applicable fees for initial application and amendment to an approved maintenance schedule are found in CAR 104 Schedule VI. The maintenance schedule amendment fee would not apply when TCCA directs aircraft owners/operators to amend their maintenance schedule through such means as an Airworthiness Directive (AD). Some fees associated with the approval of a maintenance schedule (initial and amendment) are subject to inflation adjustment. Please refer to the Transport Canada’s service fees webpage for further details on fees. Applicable payment can be made through the Online Payment System.

(3) The TCCA service standards associated with approving a maintenance schedule, initial and amendment, are found on the Aviation service standards webpage.

4.2 Application

(1) Applications, proof of payment and supporting documentation are submitted in accordance with STD 625 Appendix D to the applicable TCCA Office/Centre/Branch having oversight responsibilities on the owner/operator of the aircraft.

(2) The application should include the necessary owner/operator and aircraft information, and supported by the proposed checklist(s), including instructions and procedures, and the necessary substantiating data for which the maintenance schedule is based upon.

(3) Maintenance schedules are approved for a particular make and model of aircraft, as stated in STD 625 Appendix D, meaning the specific model designation assigned by the manufacturer or type certificate holder. Before including multiple models on one application form, a determination should be made to ensure that multiple models of the same make can be included on a single maintenance schedule approval by reviewing the aircraft ICAs and their differences to support multiple models. Supporting evidence of this determination may be required as part of the application.

5.0 Schedule development

5.1 Aircraft and operating variables

(1) When developing a maintenance schedule, an applicant needs to consider aircraft and operating variables that may impact the proposed scheduled maintenance to ensure the aircraft’s continuing airworthiness and safe operation. The following list is non-exhaustive which the aircraft owner/operator will need to consider when developing a proposed maintenance schedule for the aircraft:

Projected aircraft annual utilization (hours and cycles):
1. The manufacturer may recommend different schedules and/or other recommended tasks based on projected utilization (e.g., low utilization versus high utilization).
Aircraft role(s);
1. The type of aircraft roles may include firefighting, cargo, operating on skis, etc. This also includes the Specific Approvals (SA) that would be required to operate the aircraft.
Aircraft age – total hours and cycles;
1. The amount of hours and cycles on the aircraft may require additional maintenance as recommended by the aircraft manufacturer. In cases where the recommendations do not address such a high time aircraft, consultation with the aircraft manufacturer may be required.
Operating environment.
1. For example, long term exposure to very hot or very cold temperatures, environmental pollutants such as salts, flights close to mountainous areas causing turbulence and wind shear, and stress on the aircraft structure and flight controls. The manufacturer may have additional maintenance recommendations for these types of operating environment. In cases where the recommendations do not address the operating environment, consultation with the aircraft manufacturer may be required.

5.2 Small aircraft maintenance schedule basis

(1) The basis for a small aircraft maintenance schedule is listed in STD 625.86(5). Typically, no Maintenance Review Board Report (MRBR) will exist. Therefore, the order of preference will be:

The current recommendations of the aircraft manufacturer;
A maintenance schedule approved by TCCA for use by another Canadian operator;
Other data acceptable to TCCA.

(2) Where deviation from the order of preference above is requested, the aircraft owner/operator will demonstrate that the proposed basis of the schedule is more appropriate to their operation as described in STD 625.86(5).

(3) Owners/operators of small commercially operated aircraft, other than pressurized turbine-powered aircraft and balloons, may choose to base their maintenance schedule on STD 625 Appendix B Part I, as indicated in STD 625.86(3). In this case, the scheduled tasks shall be performed at intervals not exceeding 100 hours or 12 months, whichever occurs first.

(4) STD 625 Appendix B Part I is not an inspection checklist. For each aircraft, an appropriate checklist containing each task and its interval needs to be developed to ensure that the airframe, engine(s), propeller(s), appliances, survival equipment, emergency equipment and other equipment installed on the aircraft are inspected to ensure that they are airworthy. Manufacturer's checklists may be used, provided they include at least the items listed in STD 625 Appendix B Part I.

(5) Owners/operators of small commercially operated aircraft may choose to use a progressive maintenance schedule, including a schedule recommended by the aircraft manufacturer, provided it meets the requirements in STD 625 Appendix D (4).

(6) Regardless of the chosen basis, the applicant will submit the necessary substantiating data to TCCA for review in accordance with STD 625 Appendix D. The basis of the maintenance schedule should be clearly indicated in the 24-0055A application form and supplemented by inspection checklists, including the instructions and procedures.

Note: Refer to Appendix A of this manual for further information on maintenance schedule basis.

5.3 Large aircraft maintenance schedule basis

(1) The development of a large aircraft maintenance schedule is based upon data obtained from a current and approved MRBR as indicated in STD 625.86(5).

(2) Where no MRBR exists, the order of preference is as follows:

The current recommendations of the aircraft manufacturer;
A maintenance schedule approved by TCCA for use by another Canadian operator; and
Other data acceptable by TCCA.

(3) Where deviation from the order of preference above is requested, the aircraft owner/operator should demonstrate that the proposed basis of the schedule is more appropriate to their operation as described in STD 625.86(5).

Note: Refer to Appendix A of this manual for further information on maintenance schedule basis.

5.4 Out of phase tasks and equipment maintenance requirements – STD 625 Appendix C

(1) STD 625 Appendix C items are to be complied with and form part of the maintenance schedule as described in STD 625.86 and STD 625 Appendix D.

(2) The intervals specified therein are initial intervals that are to be used by a new operator of an aircraft type. The initial intervals may be amended once operating experience on type is gained and supported by the results from the aircraft owner/operator’s reliability program or MMP. See AC 605-002 and AMA 571.101/1 for further guidance.

(3) In STD 625 Appendix C (2), aircraft owners/operators may be authorized by TCCA to deviate from an interval if they can demonstrate that the requirement as written does not apply due to the design of the installed equipment. This does not mean that the task can be deleted as part of the maintenance schedule, but that based on justification and supporting documentation, the interval may be amended. Factors to consider are:

the original equipment manufacturer’s (OEM) recommendations;
the aircraft manufacturer recommendations;
the task type and proposed interval as compared to what is in STD 625 Appendix C; and
the description/operation of the system architecture of the equipment as installed in the aircraft.
Note: A declaration from the aircraft manufacturer or OEM of no technical objection or similar wording supporting the change is insufficient to deviate from the intervals in STD 625 Appendix C.

(4) For item 5 of STD 625 Appendix C – Variable Pitch Propellers, where the propeller manufacturer has made air time recommendations between overhauls, overhaul is to be accomplished at the air time recommended by the propeller manufacturer or ten years, whichever occurs first. If a variable pitch propeller manufacturer has recommended a calendar time interval, an owner/operator may choose to follow the propeller manufacturer’s calendar recommendation provided the overhaul calendar time is no more than ten years.

Note: The ten-year overhaul interval for variable pitch propellers starts either from its initial date of installation following manufacture or begins upon the signing of the maintenance release of its last overhaul.

(5) For engine maintenance requirements, STD 625 Appendix C item 7 provides options for the overhaul intervals:

in accordance with intervals recommended by the engine manufacturer:
1. in accordance with the engine manufacturer’s ICAs overhaul interval;
in accordance with an alternative hard time interval:
1. normally established following an engine trial program to extend the time between overhaul (TBO) – see AC 605-002 for more information;
in accordance with an engine on-condition maintenance program:
1. program established by the engine manufacturer (e.g., Service Bulletin (SB));
2. program established based on operator reliability program – see AC 605-002 for more information;
3. piston engine program established based on TCCA Airworthiness Notice (AN) B041.
Note: Based on an engine manufacturer’s recommended on-condition program, the expectation is to follow all the manufacturer recommendations to meet this option in STD 625 Appendix C.

(6) For item 10 of STD 625 Appendix C - non-stabilized Magnetic Direction Indicators (MDIs), where the aircraft and operation meet paragraph (b) of item 10, the aircraft owner/operator will reference the procedure for monitoring and recording the performance of the MDI(s) as part of the maintenance schedule application and provide a copy of the procedure for review to TCCA.

(7) Where installed equipment is not listed in STD 625 Appendix C, the aircraft owner/operator is responsible for identifying any other maintenance requirements relating to other installed equipment such as by consulting the OEM recommendations, STC supplemental ICAs or incorporated SBs.

(8) Refer to STD 625 Appendix C for other applicable equipment that may be required to be included as part of the maintenance schedule based on the aircraft’s installed equipment.

Note: For maintenance schedule tasks involving used parts with a calendar-based interval that require maintenance to be performed off-wing (e.g., in a shop environment), the expectation is that the next calendar interval begins upon the signing of the maintenance release for the maintenance performed off-wing. Where the part is being replaced with a new part to comply with the scheduled calendar interval, the expectation is that the next calendar interval starts upon installation of the part on the aircraft.

5.5 Specific Approvals (SAs) maintenance requirements

(1) Some SAs have specific maintenance tasks and intervals as part of the approval that are to be complied with and included in the maintenance schedule. Some SAs include a reliability program that will be required to be incorporated into the operator’s maintenance control system.

(2) Depending on the SA requested, aircraft owners/operators should consult the appropriate TCCA documents, such as TPs, and 500, 600 and 700 series ACs. Examples of SAs include those for Instrument Flight Rules, ETOPS, Category (CAT) II & III approach minima and operation with Reduced Vertical Separation minimum (RVSM).

Note: Reference to CARs amendment SOR/2025-226, the EDTO regime will replace ETOPS.

5.6 Maintenance schedule checklists, instructions and procedures

(1) Together with the applicable application form, the applicant should submit the instructions and procedures for the performance of the proposed maintenance schedule provided in a form of a checklist or checklists and contain the applicable information in STD 625 Appendix D (3)(a) and applicable out of phase tasks listed in STD 625 Appendix C.

(2) STD 625 Appendix D (3)(a) itemizes the required details to form part of the application which can be directly inputted or referenced in the applicable application form.

(3) The small and large aircraft application forms include an area for instructions and procedures for the applicant to provide details on the conduct of the schedule. The checklist(s) to be used may be referenced here.

(4) Submission of the aircraft manufacturer’s checklists or inspection sheet/task card packages may be sufficient to identify all required items. However, aircraft owners/operators may need to develop their own documents depending on factors such as complexities of the proposed schedule, re-grouping of tasks and the type of equipment installed on their aircraft.

(5) Pre-flight checks performed by flight crew or daily and pre-departure checks intended to be performed by unlicensed personnel do not need to be included as part of the application for an approved maintenance schedule. These tasks should be addressed as part of the operator’s maintenance control system such as in the Maintenance Control Manual (MCM).

(6) STC modifications that have been installed on the aircraft, engine, and/or propeller may include scheduled maintenance tasks as part of a maintenance manual supplement, or supplemental ICAs, which should be included in the maintenance schedule.

Note: For maintenance schedule tasks involving used parts with a calendar-based interval that require maintenance to be performed off-wing (e.g., in a shop environment), the expectation is that the next calendar interval begins upon the signing of the maintenance release for the maintenance performed on the used part. Where a used part is being replaced with a new part to comply with the scheduled calendar interval, the expectation is that the next calendar interval starts upon installation of the new part on the aircraft.

(7) For proposed tolerances to scheduled maintenance tasks the reference to the operator’s maintenance control system procedures detailing the control and authorization of the use of a tolerance are to be included.

Note: Refer to section 5.7 of this manual for further details on tolerances.

(8) Include the identification and reference to all applicable AWLs such as Airworthiness Limitation Items, life-limited parts, Certification Maintenance Requirements (CMRs) and AWLs mandated through Ads in the maintenance schedule.

Note: Installation of modifications through STCs, or repairs through RDAs, may also have approved AWLs requiring the performance of maintenance that need to be incorporated into the maintenance schedule.

(9) Where an AD requires incorporation or provides an option to incorporate tasks into the maintenance schedule, the maintenance schedule application should identify those tasks with reference to the AD to ensure its traceability.

Note: ADs not required to be incorporated in the aircraft maintenance schedule are complied with under CAR 605.84 and managed outside of the maintenance schedule by the operator’s maintenance control system.

5.7 Tolerances

(1) The use of tolerances to scheduled maintenance task intervals is permitted, provided it is approved by TCCA as part of the maintenance schedule.

(2) Tolerances are not permitted for AWLs and ADs.

(3) Tolerances may apply to tasks controlled by hours, calendar, and cycles. The following are examples of tolerances that may be approved by TCCA:

Hours: 10% of the applicable task interval, or 500 hours, whichever is less.
Calendar: 10% of the applicable task interval or 3 months, whichever is less.
Cycles: 10% of the applicable task interval, or 50 cycles, whichever is less.

Note: For items controlled by more than one limit (e.g., items controlled by both hours and calendar), the more restrictive limit is to be applied. Tasks subject to TCCA approved trial programs may vary the time trial periods by a maximum of 50 hours, provided that the agreed trial program does not specifically exclude such variation.

(4) The use of manufacturer’s recommended tolerances or use of higher tolerances may be acceptable. The aircraft owner/operator would be expected to provide supporting evidence and documentation that the use of such tolerances will not affect the safe operation of the aircraft.

(5) In the case of an aircraft operating pursuant to CAR 406, 604 or Part VII, use of tolerances shall be authorized and controlled in accordance with the operator’s approved policies and procedures as set forth in the applicable operations manual (CAR 604) or MCM (CAR 406 or Part VII), in accordance with STD 625.86(8). The policies and procedures should include:

a review of the use of the tolerance, including prior use if applicable;
the circumstances that lead to the use of the tolerance;
the effect of the safe operation of the aircraft during the tolerance period being applied;
the supporting justification and documentation for the use of the tolerance;
the person or persons authorized to approve the use of the tolerance within the operator;
the need to perform maintenance prior to the tolerance being applied;
the necessary technical record entries;
the details of the technical dispatch procedure of an aircraft with an applied tolerance.
Note: As part of their quality assurance program, aircraft owners/operators should perform a review to determine whether an amendment to the maintenance schedule would be more appropriate where tolerances are often utilized for a particular task. Refer to section 7.0 of this manual for amendments to an approved maintenance schedule.

(6) The policy and procedures for the use of tolerances are to be referenced as part of the maintenance schedule.

5.8 Substantiating data for the basis of the maintenance schedule

(1) As part of the application for an approved maintenance schedule, the applicant is expected to submit substantiating data on which the maintenance schedule is based, as required in STD 625 Appendix D (3)(b), including such things as the identification of any differences from the basis such as deletion or moving of tasks from scheduled checks, and proposed intervals other than those contained in the basis.

(2) Any changes to the basis will require justification from the operator to support the application and demonstrate that the proposed maintenance schedule basis will not affect the safety operation and continuing airworthiness of the aircraft.

(3) Substantiating data supporting for the use of the basis of the maintenance schedule includes:

Source documents forming the basis including its document number and revision (non-exhaustive list of examples depending on aircraft type, its configuration and operation):
1. MRBR;
2. Aircraft ICAs;
3. Engine(s) ICAs;
4. Auxiliary Power Unit (APU) Maintenance Manual / ICAs;
5. Propeller(s) ICAs;
6. Airworthiness Limitations Section(s);
7. Modifications and repairs (e.g., Supplemental ICAs from installed STCs, RDAs, manufacturer’s SBs);
  Note: SBs that are incorporated into the aircraft for which includes additional scheduled maintenance tasks to be performed are to be referenced in the maintenance schedule. Other SBs that do not affect the scheduled maintenance for the aircraft are not required to be referenced in the maintenance schedule and should be tracked separately by the owner/operator.
8. Supplemental Integrity Instructions, reference to CAR 521.369;
9. ADs that have a corrective action to incorporate the AD tasks into the approved maintenance schedule.
10. Additional Maintenance Instructions such as Corrosion Prevention and Control Program (CPCP), installed equipment manufacturer’s recommendations and other recommendations from the aircraft manufacturer;
11. Applicable SA (e.g., RVSM) maintenance requirements.
  Note: Refer to Appendix A of this manual for further details on revision status of reference documents, using specific revision number versus using latest revision for the basis of a maintenance schedule.

5.9 Interim maintenance schedules

(1) An interim maintenance schedule may be approved under STD 625.86(4) while the complete initial maintenance schedule is being developed by the aircraft owner/operator.

(2) The proposed interim schedule should include the necessary maintenance tasks and intervals based on the length of time that the interim schedule will cover. For example, where the proposed interim schedule covers the first 6 months of operation, it will contain all necessary scheduled maintenance tasks and intervals expected to be performed during that time.

(3) The expectation is that the aircraft owner/operator develop a complete initial maintenance schedule for review and approval by TCCA prior to the end of period that the approved interim maintenance schedule will cover. If the approved interim maintenance schedule no longer covers the use of the aircraft, it would no longer meet CAR 605.86.

5.10 Maintenance schedule document control

(1) Maintenance schedules are amended and revised periodically based on such things as configuration changes to the aircraft, updates to scheduled maintenance recommendations from the manufacturer, reliability program data, and results from operator quality assurance audits verifying the effectiveness and continued compliance of the maintenance schedule.

(2) Based on this, appropriate content controls are required to ensure its status, and that amendments to the maintenance schedule are shared or made available to the organizations performing maintenance on the operator’s aircraft, and to their maintenance control and technical dispatch.

(3) The content controls include:

Revision control: means to determine its revision status, list of effective pages / sections, record of revisions.
Distribution control: to whom the maintenance schedule amendments are shared to, including where applicable, inside and outside their organization.

(4) The proposed maintenance schedule and the operator’s maintenance control system should address revision and distribution control to ensure maintenance organizations and personnel receive the updated revisions.

(5) For Part VII operator’s, additional information can be found in TP 14408 – Transport Canada Civil Aviation Guidelines: Maintenance Control Manuals.

6.0 Periodic verification of an approved maintenance schedule

(1) Each aircraft owner/operator with an approved maintenance schedule will use suitable methods to ensure that each schedule continues to remain effective and in compliance with the CARs as part of their maintenance control system and quality assurance program.

(2) This is accomplished through periodic verification of the approved maintenance schedule by reviewing data such as changes to the manufacturer’s recommendations (aircraft, engine, propeller, appliance and/or part) for scheduled maintenance, reliability data collected as part of operator experience on the specific aircraft type, changes in aircraft configuration, modifications and repairs embodied in the particular aircraft, and changes in aircraft or operating variables.

(3) The frequency of the periodic verification will be set as part of the operator’s maintenance control system and quality assurance program.

7.0 Amendments to an approved maintenance schedule

(1) The application should include the necessary owner/operator and aircraft information, the affected task(s), the type of amendment, reasons triggering the amendment (e.g. change to manufacturer’s recommendations, reliability data analysis, periodic verification results), substantiating data supporting the amendment, and that it will not affect the safe operation and continuing airworthiness of the aircraft.

Note: Refer to section 4.0 of this manual for information on forms, fees and service standards.

(2) Amendments to an approved maintenance schedule will consist essentially of the following types:

Addition of tasks or reduction of intervals, to ensure that acceptable levels of safety and reliability are maintained;
Deletion of tasks or interval escalations, to achieve reductions in operating costs;
Re-arrangement of existing tasks and intervals into different check packages, to cater for changes in route structure or timetables, or to obtain improved equipment availability;
Changes to aircraft / operating variables, fleet size, etc.;
Safety-related changes directed by TCCA, e.g., through the issuance of an AD.
Note: For safety-related changes directed by TCCA, e.g., through the issuance of an AD, no fee is charged.

(3) Maintenance schedule amendments are approved by TCCA, unless prior approval has been obtained to incorporate amendments directly through the air operator’s approved MCM and MMP.

(4) Amendments to AWLs and ADs are not permitted. Please refer to CAR 605.84 and AC 605-005 for further details.

(5) To request an amendment, the appropriate application, proof of payment and supporting documentation are submitted to TCCA in accordance with STD 625 Appendix D and STD 625.86(11) through the applicable Office/Centre/Branch having oversight responsibilities on the owner/operator of the aircraft.

Note: Further guidance on reliability methods for the amendment of maintenance schedules and MMP is found in AC 605-002 and AMA 571.101/1.

7.1 Addition of tasks or reduction of intervals

(1) Prior approval is not required to add tasks or shorten task intervals. The expectation is that the aircraft owner/operator notifies their TCCA Principal Maintenance Inspector (PMI) of these changes e.g., via email, as soon as practicable. Circumstances may include where the aircraft owner/operator elects to perform an extra inspection or perform an inspection more often beyond what has been approved in their maintenance schedule.

(2) This does not include, e.g., the incorporation of modifications and repairs, changes in operation such as addition of an SA, changes in aircraft / operating variables, that would affect the continued compliance of the maintenance schedule. The aircraft owner/operator is expected to apply for amendment unless prior approval has been obtained to incorporate amendments directly through the air operator’s approved MCM and MMP.

7.2 Deletion of tasks and interval escalations

(1) Deletion of a task from an approved maintenance schedule will depend upon the basis used to establish the initial schedule. The applicant should demonstrate that the task doesn’t apply to their operation or aircraft configuration and that the deletion of this task will not affect aviation safety. The applicant is expected to provide substantiating data to support the amendment.

(2) If the approved maintenance schedule was based upon an MRBR, only operational or economic tasks may be removable, but safety route tasks (category 5 or 8 tasks) should never be deleted. MRBR program rules need to be reviewed when considering deletion of a task. The same principles would apply when the approved maintenance schedule is not based on an MRBR: tasks established as safety-driven tasks are not eligible for deletion, whereas operational or economic tasks may be considered for removal, provided it is supported by substantiating data.

(3) Following a period of operator experience on type in which a task has been performed routinely without the detection of defects/faults, it may be appropriate to consider escalating the task interval. However, the absence of defects/faults alone does not necessarily constitute sufficient justification for interval escalation, and certain categories of tasks may not be eligible for escalation at all. Any request to escalate an interval is expected to be supported by substantiating data and that the proposed escalation will not affect the safe operation and continuing airworthiness of the aircraft.

(4) The quantity and type of data required to substantiate the change will depend both on the frequency of the task and on the reason for its inclusion in the aircraft manufacturer’s recommended program. Sufficient level of operating experience on type should be accumulated before applying for amendment to the maintenance schedule. As a minimum, the required experience would normally be approximately one year, or one complete task interval, whichever is the greater.

High frequency scheduled inspections would require a relatively high volume of data, in the order of 25-50 completed inspections or more.
In contrast, infrequent scheduled inspections would require the operator to demonstrate satisfactory completion of at least one complete interval between the tasks under review.
Similarly, changes to task intervals for safety reasons (e.g. category 5 or 8 tasks as part of an MRBR) will require significantly more substantiating data than those included primarily for economic or operational efficiency reasons.

(5) A demonstration that the amendment to the safety related task will not expose the aircraft or system to an unsafe condition will be required. This may involve additional documentation from engineering. This documentation may include analysis and calculations considering the original design philosophy. It will be necessary to refer to the original basis of the aircraft manufacturer’s recommended program to determine the reason for each task.

(6) Except where approved as part of an MMP, TCCA will review the data submitted to confirm that an acceptable level of safety can be maintained with the adjusted interval frequency or deletion of a maintenance task to ensure the safe operation and continuing airworthiness of the aircraft.

8.0 TCCA review and approval

8.1 General procedures

(1) Applications and supporting documentation are reviewed by the applicable TCCA Office/Centre/Branch having oversight responsibilities on the owner/operator of the aircraft.

(2) The assigned TCCA PMI will first check the application form and supporting documentation to ensure that it appears to be complete. The required documentation is:

Applicable application form duly completed, reflecting the aircraft and its operation;
The proposed checklist(s), including instructions and procedures;
Substantiating data for which the maintenance schedule is based upon; and
Proof the applicable fee has been paid.

(3) The TCCA PMI may consult with the TCCA Principal Operations Inspector (POI) assigned to the operator on the type of operation, the SAs requested, and/or the aircraft configuration, etc. that may help in the review of the application.

(4) If the application is complete, the TCCA PMI can proceed with the review. However, if the application is incomplete and/or documents seem to be missing or incomplete, the TCCA PMI should communicate with the applicant and describe what is missing from the request.

Note: For denying or approving an application for an approved maintenance schedule, communication with the applicant should be done in an official capacity such as via email or official letter.

8.2 Review and approval of initial application

(1) The TCCA PMI will review the submitted application form, accompanying substantiating data, and the proposed maintenance schedule, in accordance with STD 625.86, STD 625 Appendix C and D, applicable operational requirements and sections of this manual in order to:

Verify compliance with the basis of the maintenance schedule:
1. Basis aligns with STD 625.86(5); or
2. Where deviation from the order of preference in STD 625.86(5) is requested, review supporting justification submitted by the applicant that the proposed basis of the schedule is more appropriate to their operation, as described in STD 625.86(5);
  Note: refer to Appendix A of this manual for further information on maintenance schedule basis.
Verify compliance with the source documents and their revision status;
Note: refer to Appendix A of this manual for further information on revision status of source documents.
Verify compliance with the maintenance schedule content and document control;
Where the proposed maintenance schedule deviates from the source documents, ensure that the technical justifications provided by the applicant are appropriate, including that it will not affect the safe operation and continuing airworthiness of the aircraft;
Verify proposed tolerances and procedures for their use, authorization and control;
Note: No tolerances shall be applied to ADs or AWLs.
Where applicable, review reliability program(s) (SAs, on-condition programs, etc.).

(2) For the review of interim schedules, the TCCA PMI will also refer to section 5.9 of this manual.

(3) If the TCCA PMI’s review determines that the applicant’s initial submission is incomplete, does not reflect the entire aircraft as configured, or otherwise presents an unacceptable safety risk, the TCCA PMI should reject the proposed maintenance schedule and notify the applicant of the deficiencies.

(4) As part of the review, an aircraft inspection may be carried out by the TCCA PMI to verify the aircraft configuration to the proposed maintenance schedule. When related to an application for an SA, the TCCA PMI will coordinate with the TCCA POI to arrange for an aircraft inspection with the applicant. Otherwise, the TCCA PMI will coordinate with the applicant.

(5) If the TCCA PMI’s review determines that the applicant’s initial submission is acceptable and meets STD 625 Appendix D, the TCCA PMI will approve the maintenance schedule, indicate the allocated maintenance schedule approval number, the revision number 0 (zero), and provide a copy of the approved maintenance schedule to the applicant. A copy will be saved on the TCCA owner/company file.

Note: For initial approvals, the revision status – list of effective pages on the applicable application form should be blank. The revision date of each page should be the TCCA approval date of the maintenance schedule.

8.3 Review and approval of amendment to a maintenance schedule

(1) The TCCA PMI will review the application form 24-0055C, and applicable 24-0055A or 24-0055B form with the proposed changes, along with the accompanying substantiating data as part of the amendment request. The review shall be done in conjunction with section 7.0 of this manual.

(2) As part of the application, the request should indicate the affected items, the action to be taken, and the justification for the change, and where applicable, consider the operator’s experience on type and the data gathered from the operator’s reliability program.

(3) If the TCCA PMI’s review determines that the applicant’s submission is incomplete, does not reflect the entire aircraft as configured, or otherwise presents an unacceptable safety risk, the TCCA PMI should reject the proposed maintenance schedule and notify the applicant of the deficiencies.

(5) If the TCCA PMI’s review determines that the applicant’s submission is acceptable and meets STD 625 Appendix D, the TCCA PMI will approve the maintenance schedule, indicate the allocated maintenance schedule approval number, the subsequent revision number (e.g., if previous revision was 1, then indicate 2), and provide a copy of the approved maintenance schedule to the applicant. A copy of the approved amendment will be saved on the TCCA owner/company file.

Note: For approval of amendments, the revision status – list of effective pages on page 2 of the applicable 24-0055A or 24-0055B form should reflect the amendments made based on the previous approved maintenance schedule revision. The revision date of each page should coincide with the revision dates in the revision status – list of effective pages on page 2 of the applicable form.

9.0 Information management

(1) For TCCA, all documents related to the application, amendment, and approval of aircraft maintenance schedules should be saved in the appropriate owner or company file, using the appropriate subject file classification and naming conventions.

10.0 Document history

(1) TP 13094, Revision 3, dated June 2006 RDIMS# 21478409 English, RDIMS# 21478424 French

(2) TP 13094, Revision 2, dated June 2004 RDIMS# 883184 English, RDIMS# 883189 French.

(3) TP 13094, Revision 1, dated February 1999 RDIMS# 1395145 English, RDIMS# 1395150 French

(4) TP 13094, Revision 0, dated October 1997.

11.0 Contact us

For more information, please contact:
Chief, Operational Airworthiness Division, Standards Branch (AARTM)
E-mail: jeff.phipps@tc.gc.ca

We invite suggestions for amendment to this document. Submit your comments to:
Standards Branch Documentation Services
E-mail: AARTDocServices-ServicedocAART@tc.gc.ca

Appendix A — Maintenance schedule basis and revision status of source documents

Use the following information and guidance when choosing a maintenance schedule basis and revision status of the maintenance schedule reference documents.

1.0 Maintenance schedule basis

1.1 MRBR

(1) Schedules based on a MRBR will include all the tasks listed in the report, plus any additional tasks arising from modifications to the aircraft, the role in which the aircraft is to be employed, planned utilization or the environment in which it is to be operated.

(2) The intervals between tasks specified in the MRBR are the maximum intervals for the operator’s initial schedule.

(3) MRBR usually address a standardized aircraft configuration and will therefore be supplemented by additional tasks to ensure the serviceability of optional equipment and systems installed as part of customer specific modifications such as galley and passenger service equipment, life jackets, medical kits, entertainment systems, mission equipment, etc.

(4) The aircraft type certificate holder may produce a Maintenance Planning Document (MPD) or other developed document to assist operators in planning and structuring a maintenance schedule. This document may also include other tasks such as those associated with AWLs, structural fatigue related tasks for damage tolerant aircraft, component replacement times and inspection intervals. It may also include recommended tasks for equipment and parts of the aircraft not addressed by the MRBR.

(5) In the case of older aircraft, where the type certificate holder has not kept the MRBR current, the MPD or other document may have different maintenance tasks than those that were originally developed as part of the MRB process. Where these types of documents are being used as source documents for the maintenance schedule, they should be included as part of the application, in support of the basis.

1.2 Current recommendations of the aircraft manufacturer

(1) Aircraft manufacturer’s recommendations are not limited to the basic recommended schedule. Recommendations are issued in the form of ICAs and/or publications issued by the Type Certificate holder (aircraft, engine, or propeller) and the recommendations from the manufacturer of installed equipment on the aircraft.

(2) These could include supplementary documents issued and published by the manufacturer that contain recommended scheduled inspections, replacement of components, overhaul, etc. These supplementary documents could be in the form of servicing instructions, SBs or equivalent documents.

(3) Maintenance schedules based upon aircraft manufacturer recommendations may be approved, provided that all of the recommendations are being used and/or have been considered by the aircraft owner/operator. Those recommendations not being considered would require justification of their omission as part of the basis. In addition, the aircraft owner/operator would need to take into consideration such things as the aircraft’s operational role, utilization rate, history and supportability, environment and configuration, and the need for compliance with operational requirements and that the omission would not have any adverse effect on the safe operation and continuing airworthiness of the aircraft.

1.3 Maintenance Schedules approved from other Canadian operators

(1) Although maintenance schedules are not transferable, operators may base their schedules upon those of another Canadian operator. This normally occurs when an operator purchases or leases an aircraft and wishes to take over the seller’s maintenance schedule as part of the package.

(2) An applicant basing their maintenance schedule on another Canadian operator’s approved maintenance schedule will require substantiating data to support its use and should include support for its use as the basis from the other Canadian operator. The applicant should be prepared to conduct an analysis of schedules developed in this manner as it will involve a comparison between the two operations, including each other’s maintenance control systems.

(3) Approval will depend upon the applicant’s ability to demonstrate that the role, aircraft configuration, route structures, type of evaluation program and environment are essentially the same in both cases.

(4) A comparison of the reliability programs of the previous operator and the applicant would be required.

(5) In addition, the assessment will take into account the relative experience of each operator with the aircraft type, or with similar types.

(6) An operator may not take credit for another operator’s established TBO, or other intervals, unless the operator can show equivalent competence and experience.

1.4 Other data acceptable to TCCA

(1) Relevant data may come from a wide range of possible sources, including schedules approved by other airworthiness authorities, military schedules, and in rare cases, completely new schedules resulting from the operator’s analysis of the aircraft design.

(2) The depth of review required for approval will depend upon the circumstances of the individual case.

(3) The onus is on the applicant to demonstrate that the data presented is relevant and appropriate for their aircraft and operation, and that it will not affect the safe operation and continuing airworthiness of the aircraft.

2.0 Revision status of source documents

2.1 Using a specific revision

(1) An applicant may reference a specific revision of the source documents in their application for an approved maintenance schedule provided it is the most current at the time of application.

(2) Once the maintenance schedule is approved, it will be up to the operator to review its effectiveness as part of the operator’s quality assurance program through such means as collecting reliability data to evolve their maintenance schedule and to not rely on the aircraft manufacturer to update their recommended scheduled maintenance publications.

(3) An applicant may then apply to TCCA for an amendment to their maintenance schedule and present the substantiating data such as reliability data in support of their application for amendment. Refer to AC 605-002 for more information on reliability programs and section 7.0 of this manual for amendments to an approved maintenance schedule.

2.2 Using latest revision

(1) An applicant may reference the ‘latest revision’ for the basis document, which allows them to adopt the most recent changes published by the manufacturer, without requiring an amendment to their approved maintenance schedule every time a new recommendation has been released and published.

(2) In most cases, using the latest revision of an MRBR is practical as it is subject to a periodic review under the MRB process to be an up-to-date document. In this case, operators with an MRBR as the basis may choose to use the term ‘latest revision’ in their application for maintenance schedule approval.

(3) If using “latest revision” as the basis for the maintenance schedule, the applicant would need to ensure that the maintenance schedule continues to be in compliance with requirements, as part of their Maintenance Control System and Quality Assurance Program. The applicant would be expected to establish maintenance control procedures (e.g., MCM) for the review, amendment and distribution of their approved maintenance schedules. The procedures should take into account the time needed to accomplish the changes as part of the continued compliance of their maintenance schedules.

Maintenance Schedule Approval Policy and Procedures Manual - TP 13094

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