# AC 120-16G: Air Carrier Maintenance Programs

- Type: Advisory circular (guidance, not mandatory unless a rule or AD requires it)
- Status: Current
- Approved: January 4, 2016
- Last reviewed: August 6, 2024
- Family: AC 120-16
- Cancels: [AC 120-16F](https://openairdocs.org/ac/120-16F)
- 14 CFR parts: 121, 135
- 14 CFR sections: [135.411](https://www.ecfr.gov/current/title-14/section-135.411)
- Pages: 59
- PDF: https://openairdocs.org/files/sha256/5f/df/5fdffb772453de4087182d341a4ec7b17b493152e30d0d2841403ca40d5ade2f
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/39CB31CA8F0ED9EB86257F4900681109.0001
- DRS record last changed: November 22, 2025
- Page: https://openairdocs.org/ac/120-16

## Versions

- [AC 120-16G](https://openairdocs.org/ac/120-16) (Current), approved Jan 4, 2016, 59 pages
- [AC 120-16F](https://openairdocs.org/ac/120-16F) (Historical), approved Nov 15, 2012, 56 pages
- [AC 120-16E CHG 1](https://openairdocs.org/ac/120-16E-CHG-1) (Historical), approved Jun 7, 2011, 49 pages. CHG 1 of AC 120-16E.
- [AC 120-16E](https://openairdocs.org/ac/120-16E) (Historical), approved Sep 11, 2008, 50 pages
- [AC 120-16D](https://openairdocs.org/ac/120-16D) (Historical), approved Mar 20, 2003, 52 pages
- [AC 120-16C](https://openairdocs.org/ac/120-16C) (Historical), approved Aug 8, 1980, 8 pages

## Text

Each page's text from the PDF; open the PDF at a page with #page=N.

### Page 1

Advisory U.S. Department of Transportation Federal Aviation Circular Administration Subject: Air Carrier Maintenance Programs Date: 1/4/16 AC No: 120-16G Initiated by: AFS-300 Change:

This advisory circular (AC) explains what the term “maintenance program” means. Our explanation describes the scope and content of air carrier aircraft maintenance programs. This is important as there is a significant difference between an air carrier maintenance program and an inspectio n program used in non-air carrier maintenance operations. We explain the background of these programs as well as the Federal Aviation Administration’s (FAA) regulatory requirements. We also describe and explain each of the 10 elements of air carrier maintenance programs. When we use “must” or “will” in this AC, we are referencing actual regulatory requirements. When we use “we,” “us,” or “our” in this AC, we mean the FAA. When we use “you,” “your,” or “yours,” we mean you, the air carrier. When we use the term “person,” it has the same meaning as that in Title 14 of the Code of Federal Regulations (14 CFR) part 1, § 1.1.

This AC is one method of compliance with the requirements of the regulations. Instead of following this method, you may elect to follow an alternate method, provided that your method is acceptable to us. Because the method of compliance that we present in this AC is not mandatory, the term “should” applies only if you choose to follow this particular method without deviatio n. You should tailor your maintenance program to your specific operation; therefore, we are not providing a single means of compliance that applies to all operators required to have a maintenance program. We have included informatio n in this AC about our expectations regarding your implementatio n of an air carrier maintenance program. We based these expectations on our regulatio ns. As required by 14 CFR part 121, § 121.367 and part 135, § 135.425, your maintenance program must ensure that each of your aircraft released to service is Airworthy and properly maintained for operations in air transportation; that you provide competent personnel, adequate facilities, and equipment; and that everyone who works on your aircraft follows your manual and your program.

In addition to strict complia nce with parts 121 and 135 regulations, we encourage you to consider additional processes and methodologies for use in your maintenance program, such as industry best practices, or other government guidance relevant to maintenance, preventive maintenance, and alteration activities.

ORIGINAL SIGNED by /s/ J ohn S. Duncan Director, Flight Standards Service

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**CONTENTS**

Paragraph Page

CHAPTER 1. GEN ERAL INFORMATION … 1

1-1. Purpose … 1

1-2. Cancellation … 1

1-3. Aud ience … 1

1-4. Legal Basis for Air Carrier Maintenance Program s … 1

1-5. Maintenance Program Authorization … 3

1-6. Air Car r ie rMaintenance Program Objectives … 3

1-7. Air Car r ie r Maintenance Program Elem ents … 4

CHAPTER 2. AIRWORTHINESS RESPONSIBILITY … 5

2-1. Responsibility for Aircraft Maintenance … 5

2-2. Differences Between Programs … 5

Table 2-1. Maintenance Program and Inspecti on Program Differences … 5

CHAPTER 3. AIR CARRIER MAINTENANCE MANUAL … 7

3-1. Air Car r ie r Maintenance Manual Requirem ent … 7

3-2. Rol e of You r Air Carrier Maintenance Manual … 7

3-3. Major Sections of the TypicalAir Ca rr ie rMaintenance Manual … 7

CHAPTER 4. AIR CARRIER MAINTENANCE ORGANIZATION … 11

4-1. Maintenance Organiz ati on—General … 11

4-2. Req uired Maintenance Organizatio n Management Po sitio ns … 11

4-3. Required Air Carrier Maintenance Organizatio nal Structure … 11

4-4. Separation of Inspectio n and Maintenance Departments … 12

Figure 4-1. Maintenance Organiz ati onal Chart … 14

**CHAPTER 5. ACCOMPLISHMENT AND APPROVAL OF MAINTENANCE AND**

ALTERATIONS … 15

5-1. Accomplishment of Maintenance … 15

5-2. Major Repairs and Alterations … 15

5-3. Airworthiness Release Form or Aircraft Log Entry and Approval for Return to

Service … 16

5-4. Scope of Maintenance … 16

5-5. Parts and Appliances Maintenance Program … 17

CHAPTER 6. MAINTENANCE SCHEDULE … 19

6-1. The Maintenance Schedul e … 19

6-2. The FAA’s Ro le in Re la t ion to the Maintenance Sched ule … 19

6-3. Maintenance Sched ule Co ntents … 19

Page iii

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CONTENTS (Continued) Paragraph Page

6-4. Standards for Determining Maintenance Schedules … 20

CHAPTER 7. REQ UIRED INSPEC TION ITEMS … 23

7-1. R equired Inspection Items (RII) … 23

Figure 7-1. Required Inspection Items … 24

7-2. RII Procedures, Standards, and Limits … 25

CHAPTER 8. MAINTENANCE RECORDK EEPING SYSTEM … 27

8-1. Reasons for Making and Keeping Maintenance Records … 27

8-2. Part 43 Requirements … 27

8-3. Work Performed by a Part 145 Certificated Repair Station (CRS) … 27

8-4. Air Car r ie rMaintenance Recordkeeping … 28

8-5. Mak ingand Keeping Required Records … 28

8-6. Required Air Carrier Maintenance Records … 28

8-7. When to Make Records Available to the FAA … 28

8-8. Responsibility for Making Records Available to the FAA … 29

8-9. Required Records … 29

8-10. Other Required Records and Reports … 31

8-11. Requirements for Reports of Major Alterations and Major Repairs … 34

8-12. Requirements for Historical or Source Records … 34

CHAPTER 9. CONTRACT MAIN TEN ANCE … 37

9-1. Contract Maintenance … 37

9-2. Responsibility for Maintenance Performed by Others … 39

9-3. Unscheduled Contract Maintenance Performed Away from Regular Facil ities … 39

9-4. Airworthiness Release Form or Aircraft Log Entry … 39

9-5. Evaluating New Maintenance Providers … 40

9-6. Continuing M aintenance Provi der Oversight … 41

9-7. Using a Certificated Repair Station (CRS) as O ne o f Yo ur Maintenance Provi ders … 41

CHAPTER 10. PERSONNEL TRAINING … 43

10-1. Maintenance Program Training Requi rem ents … 43

10-2. Types of Training … 43

10-3. Initial Training … 43

10-4. Recurrent Training … 43

10-5. Specialized Training … 44

10-6. Maintenance Provider Training … 44

10-7. Com petency-Based Training … 44

Page iv

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CONTENTS (Continued) Paragraph Page

CHAPTER 11. CONTINUING ANALYSIS AND SURVEILLANCE SYSTEM … 47

11-1. Back gro und o f the Continuing Analysis and Surveillance System (CASS) … 47

11-2. CASS is a Saf ety Management Tool … 47

11-3. Basic CASS Processes … 47

11-4. Risk-Based Deci sions … 49

11-5. Scope of a CASS … 49

11-6. CASS Design Principles … 49

11-7. CASS Personnel Requirements … 50

CHAPTER 12. ADMINISTRATIVE … 51

12-1. Whom to Contact … 51

12-2. Regul atory Ref erences … 51

12-3. Other Related Regulations and Guidance Material … 51

12-4. Obtaining Ref erence Material(current ed itio ns) … 52

Page v (and vi)

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**CHAPTER 1. GENERAL INFORMATION**

1-1. PURPOSE. In this advisory circular (AC), we describe the 10 elements that comprise air carrier maintenance programs and what you should include in your air carrier maintenance program. Consistent with regulations, inspectio n functio ns are an inherent and integral part of your maintenance program; they are not separate. Your maintenance manual is the part of your air carrier manual that describes your maintenance program.

1-2. CANCELLATION. This AC cancels AC 120-16F, Air Carrier Maintenance Programs, dated November 15, 2012.

1-3. AUDIENCE. This AC applies to you if you are a Title 14 of the Code of Federal Regulatio ns (14 CFR) part 119 air carrier conducting operations under 14 CFR parts 121 and/or 135. For part 135 operations, this AC applies only to those maintenance operations conducted under part 135, §§ 135.411(a)(2), 135.411(b), and 135.411(d). This AC also applies to each person employed or used by an air carrier for any maintenance, preventive maintenance, or alteration of its aircraft. We have defined the meaning of “person” in 14 CFR part 1, § 1.1 as “an individual, firm, partnership, corporation, company, association, joint-stock association, or governmental entity. ” This regulatory meaning of “person” includes a trustee, receiver, assignee, or similar representative of any of them. Whenever we say “person” in this AC, we mean the same as that in § 1.1.

**1-4. LEGAL BASIS FOR AIR CARRIER MAINTENANCE PROGRAMS.**

a. Title 49 of the United States Code (49 U.S.C.). Title 49 U.S.C. § 44701 is the primary authorit y for all air carrier Federal aviation regulat io ns. Title 49 U.S.C. § 44701 instructs us to promote the safe flight of civil aircraft in air commerce by prescribing regulations and standards in the interest of safety.

b. Air Comme rce . When prescribing regulations and standards, 49 U.S.C. § 44701 also obliges us to consider your duty to provide service with the highest possible degree of safety in the public interest, to consider differences between air transportation and other air commerce, and to classify a regulation or standard appropriate to the differences between air transportation and other air commerce. Congress has defined the term “air commerce” within 49 U.S.C. § 40102 as “foreign air commerce, interstate air commerce, the transportation of mail by aircraft, the operation of aircraft within the limits of a Federal airway, or the operation of aircraft that directly affects, or may endanger safety in, foreign or interstate air commerce.”

Simply stated, operations in air commerce are almost everything but operations in air transportation.

c. Regulations. Consistent with the requirements of 49 U.S.C. § 44701, we regulate aircraft operations at different levels of safety. Hence, we have prescribed those regulations that govern air carrier operations (air transportation) and the operations of other air commerce with a different structure to reflect the differences between these two segments of the aviation industry.

Establishing appropriate standards and regulatory requirements is a risk management process (RMP), and the underlyin g legal structure provides for more than one level of acceptable risk appropriate to different types of flight operations. We have written air transportation regulations Par 1-1 Page 1

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to be all-inclusive and stand-alone, whereas the regulations governing other air commerce are not. Similarly, we wrote the scope of responsibility for those in air transportation operations to be very broad and not shared, whereas in other air commerce we wrote the scope of responsibility to be relatively narrow and commonly shared. The regulatio ns in parts 119, 121, and 135 relate directly to air carrier maintenance programs, and reflect the highest possible degree of safety in the public interest. The regulations in 14 CFR parts 43, 65, 91, and 145 do not necessarily reflect the highest possible degree of safety in the public interest. We have included more specific references to relevant regulations in subsequent paragraphs.

d. Pe rformance-based Regul ations. We wrote almost all of the maintenance regulations in parts 121 and 135 in a performance-based format. We used the performance-based regulatory approach because it focuses on measurable outcomes, rather than on prescriptive processes, techniques, or procedures. Performance-based regulation leads to defined results without a specific direction or specific instruction in the regulation regarding how to obtain those results.

This approach permits our regulations to apply to a wide variety of certificate holders and still have the same standards. For example, our perfor mance-based regulations in part 121, § 121.367 and § 135.425 apply equally to the 1-airplane operator and the 900-airplane operator. The defined result is always the same: an Airworthy airplane that the operator has properly maintained for operations in air transportation. Performance-based regulation also permits the regulatio n to remain current in the face of advances in technology or methodology.

e. Acceptable Means of Com pliance (AMC). The other half of writing performance-based regulation is to explain what constitutes an AMC. We wrote this AC to show you what acceptable methods of compliance with the performance-based maintenance program regulatory requirements are. In this AC, we have described processes, techniques, and procedures that will lead to the defined results in the maintenance regulations. None of the informatio n in this AC is mandatory or constitutes a regulatio n. We have not included any material in this AC that imposes, reduces, or changes a regulatory burden on anyone. If you use the method of compliance presented in this AC, the term “should” used herein applies only if you choose to follow these particular methods. You should tailor your maintenance program to your particular and specific operation; therefore, we cannot provide a single means of compliance that applies to all certificate holders required to develop and implement an air carrier maintenance program.

f. Continuous Airworthiness Program (CAP). The Federal Aviation Adminis trat io n (FAA) introduced the CAP in a fina l rule at 29 Federal Register (FR) 6522 on May 20, 1964. Since then, the CAP has become known, in a colloquial sense, as a Continuo us Airworthiness Maintenance Program (CAMP). This 1964 rulemaking was our response to safety concerns, and discoveries of weaknesses in the maintenance programs of some air carriers that we found during accident investigatio ns and surveillance of operator maintenance activities. We designed the air carrier CAP to strengthen requirements for air carrier safety management activities. Each one of the air carrier maintenance program elements that we describe in this AC were a part of that 1964 rulemaking.

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1-5. MAINTENANCE PROGRAM AUTHORIZ ATION. We do not approve your CAMP.

There is no regulation that requires an approval. However, we do issue air carrier operations specifications (OpSpecs) to you that authorize you to use a maintenance program and the air carrier maintenance manual required by FAA regulatio ns. This method for authorizing operations and maintenance in air transportation evolved from the Civil Aeronautics Board’s (CAB) earlier method of issuing operating certificates and temporary permits accompanied by competency letters issued by the Secretary of Commerce. These competency letters contained informatio n that authorized the air carrier’s services, routes, aircraft, maintenance, airmen, and weather procedures; they were part of your air carrier operating certificate. We, or you, could amend them as the circumstances dictated. In 1953, we amended the Civil Air Regulatio ns (CAR) to require the issuance of air carrier OpSpecs that replaced, formalized, and standardized the competency letters that we used at the time. We also amended the regulations to state that OpSpecs were not part of your air carrier certificate. Tailored to your specific operating context and the requirements of your individ ual operations, we use OpSpecs to convey the general terms of regulations into specific terms, conditions, and limitations. As with the predecessor competency letters, OpSpecs are amended as circumstances dictate. Issued by us, the terms, conditions, and limitations contained in OpSpecs are made mandatory through specific regulatory language. (Refer to part 119, § 119.5 for the applicable language.)

**1-6. AIR CARRIER MAINTENANCE PROGRAM OBJECTIVES.**

a. Program Objectives. Your maintenance program must ensure that three specific program objectives are achieved in order to provide the highest possible level of safety in air transportation:

(1) Each of your aircraft that you release to service must be Airworthy and properly maintained for operations in air transportation;

(2) You, or any other person, perform all of the maintenance and alterations on your aircraft in accordance with your maintenance manual; and

(3) You, or any other person, provide competent personnel, and adequate facilities and equipment to perform maintenance and alterations on your aircraft.

b. Continuing Analysis and Surveillance System (CASS). Your maintenance program should also have a system of continuing surveillance, investigatio n, data collectio n, analysis, corrective action, and corrective action followup that ensures all parts of your maintenance program are effective and are being performed in accordance with your manual. “Effective” means that you are achieving the desired results according to the maintenance program objectives and the standards that you, the air carrier, set. Program performance means that all personnel are following your program as you have documented it in your manual.

Par 1-5 Page 3

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1-7. AIR CARRIER MAINTENANCE PROGRAM ELEMENTS. We explain each of these elements individ ua l ly. However, if another AC exists that provides more detailed information about one or more of the maintenance program elements, we will not explain that element in depth. Your air carrier mainte na nce program include s the following 10 elements:

• Airworthiness responsibility,

• Air carrier maintenance manual,

• Air carrier maintenance organizatio n,

• Accomplishment and approval of maintenance and alterations,

• Maintenance schedule,

• Required Inspection Items (RII),

• Maintenance recordkeeping system,

• Contract maintenance,

• Personnel training, and

• CASS.

Par 1-7 Page 4

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**CHAPTER 2. AIRWORTHINESS RESPONSIBILITY**

**2-1. RESPONSIBILITY FOR AIRCRAFT MAINTENANCE.**

a. Part 119 Certificate Holder Responsibilities. Consistent with 14 CFR part 121, § 121.363 and part 135, § 135.413, you, as a 14 CFR part 119 certificate holder, are primarily responsible for the airworthiness of your aircraft, and the performance of all maintenance or alterations on your aircraft. Your air carrier certificate makes you a maintenance entity. Under your air carrier certificate, you accomplish your own maintenance, preventive maintenance, or alterations, or you can use other persons who are not direct employees to accomplish that work.

Consistent with our regulatio ns in §§ 121.1(b) and 135.1(a)(2), the part 121 or 135 regulat io ns govern each person that you use or that you employ for any maintenance, preventive maintenance, or alteratio n of your aircraft. Each of these persons that you use must be under your direction and control, and must follow your maintenance program.

b. Maintenance Responsibilities. For any work done on your aircraft, you retain direct and primary responsibility for performing and approving all maintenance and alterations, whether you accomplish that work or whether someone else does it for you, such as a repair station. However, you always retain primary responsibility for the performance and approval of the maintenance done by that maintenance provider (MP).

2-2. DIFFERENCES BETWEEN PROGRAMS. The following table provides a comparison of the differences between air carrier maintenance programs and 14 CFR part 91 General Aviation (GA) inspectio n programs.

**TABLE 2-1. MAINTENANCE PROGRAM AND INSPECTION PROGRAM**

DIFFERENCES NOTE: The wording in part 91 is deliberately different from the wording in 14 CFR parts 121 and 135, and is consistent with the difference between air transportation and other air commerce described in 49 U.S.C. § 44701.

Elem ent Part 121 and 135 Air Carrie rs Part 91 Owne rs/Ope rato rs Use of a maintenance or an inspectio n program.

Required to use a maintenance program for its aircraft.

Required to use an inspection program.

Responsibilities within the relevant program.

Responsible for the performance of maintenance in accordance with its maintena nce program and manual, as well as the airworthiness of its aircraft, including airframes, aircraft engines, propellers, appliances, and parts thereof.

Responsible for maintaining the aircraft in an Airworthy conditio n (14 CFR part 91, § 91.403).

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Responsibilities within the relevant program.

Responsible for the development and use of the maintenance program and manual;

determining the method of performing maintenance; a required inspectio n list; a Continuo us Analysis and Surveillance System (CASS); a maintenance organizatio n that can exercise operational control over maintenance operations;

and other items that collectively and systematically serve to ensure each aircraft has been properly mainta ined for operations in air transportation and is Airworthy.

Responsible for the selection of an existing inspection program and the scheduling of aircraft for the inspectio ns, and for ensuring that discrepancies that occur between scheduled inspections are repaired.

Must determine what maintenance is required, how to do it, when to do it, perform that maintenance, and approve its own aircraft for return to service.

May authorize another person to accomplish the maintenance work, but the maintenance must be carried out according to the air carrier’s maintenance program and manual. The air carrier still retains the responsibility for the proper completio n of mainte na nce (part 121, § 121.363 or part 135, § 135.413).

Must make the airplane available to authorized and certificated person(s) who accomplish inspections and other maintenance.

Along with FAA oversight, is the primary authority with regard to its maintenance program.

Holds the primary responsibility for the performance of maintenance in accordance with its maintenance program and manual, as well as the airworthiness of its aircraft, including airframes, aircraft engines, propellers, appliances, and parts thereof.

The authorized and certificated person(s) has the responsibility to perform the maintenance properly in accordance with the manufacturer’s manual and to approve the aircraft for return to service. The owner/operator does not have this responsibility.

However, the owner/operator is responsible for ensuring maintenance personnel make appropriate entries in the aircraft maintenance records indicating the aircraft has received approval for return to service.

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**CHAPTER 3. AIR CARRIER MAINTENANCE MANUAL**

**3-1. AIR CARRIER MAINTENANCE MANUAL REQUIREMENT.**

a. Maintenance Manuals. Our regulatio ns (14 CFR part 121, §§ 121.133 and 121.369, and part 135, §§ 135.21 and 135.427) require you to have a maintenance manual. It is a required part of your air carrier manual system. Some air carriers call their manuals “specifications.”

Some use other terms.

b. Revising Maintenance Manuals. Your maintenance manual must be easy to revise and have procedures for keeping all parts of your manual up to date. Your manual may be electronic or in another form.

c. Availability. You must make copies of your manual, or appropriate portions of it, available to those persons required to comply with it, including any changes or additions. Each person who you furnish a manual or appropriate parts to must keep it up to date. You must also make your manual available to the FAA (§§ 121.137(a)(3) and 135.21(d)(2)).

d. Other Related Regulations. Other regulations that relate to your manual requirements are 14 CFR part 43, § 43.13(c), and §§ 121.135, 121.137, 121.369, 135.23, and 135.427.

**3-2. ROLE OF YOUR AIR CARRIER MAINTENANCE MANUAL.**

a. Standardization. Your maintenance manual is your key to standardized, consistent accomplishment and administration of your maintenance program. Your maintenance manual:

(1) Identifies, describes, and defines your maintenance program; and

(2) Provides instructions and procedures to administer, use, manage, and amend your program.

b. Organization and Format. Your maintenance manual is a company publicatio n, and you have sole responsibility for its organizatio n and content; however, others may compile and publish it for you. Your maintenance manual may be electronic.

3-3. MAJOR SECTIONS OF THE TYPICAL AIR CARRIER MAINTENANCE MANUAL. Your maintenance manual should have a practical organization. Typically, it will have at least three sections: the first covering administrative policies and procedures; a second covering detailed instructions for the administration, management, and accomplishment of the elements of your maintenance program; and a third covering technical data that describes maintenance standards, methods, techniques, and procedures.

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a. Administrative Policies and Procedures. The primary functio n of this part of your manual is as a management and administrative tool for organizing, directing, amending, and controlling your maintenance program. Usually, you will place organizational charts delineating the functio ns, relationships, and lines of authority between your organizatio nal elements and personnel here. You may list position descriptions, duties, responsibilities, and specific authority and responsibility attributes for each position within your maintenance organizatio n here. The authority and responsibility attributes that you place here should show who has overall authority and/or responsibility, and who has direct authority and/or responsibility for given functio ns.

b. Instructions for the Administration, Management, and Accomplishment of the Maintenance Program.

(1) This section contains detailed instructio ns for your management of the various functions and interrelationships of each maintenance program element, such as maintenance time limitations, recordkeeping, Airworthiness Directive (AD) management, maintenance program management and oversight, contract maintenance management and oversight, and personnel training. This section usually includes a description of your scheduled maintenance tasks, procedural information, and detailed instructions, or specific air carrier maintenance manual references for accomplishing your maintenance tasks. Additionally, you should describe criteria for initiating functio nal evaluatio n flights in this part of the maintenance manual, along with procedural requirements for them. In this portion of your manual, you should also include criteria and procedural informatio n for unscheduled inspectio ns, such as those associated with lightning strikes, tail strikes, engine temperature exceedance, hazardous material (hazmat) spills, hard or overweight landings, and any very high-load event.

(2) You should have a comprehensive process in the unscheduled maintenance portion of your manual that addresses those rare, extremely high-load events that occur to aircraft.

Specifically, you should have inspectio n processes that you use following certain high-load events. These particular high-load events are those for which the subsequent inspection process might benefit from the use of flight data. You should consider the events listed below as most significant:

(a) Flight Events.

• A severe turbulence encounter,

• Extreme maneuvers,

• Exceedance of speed limitations, and

• Heavy stall buffet.

(b) Ground Events.

• Hard landings,

• Overweight landings, and

• Drift landings resulting in excessive side/drag load.

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(3) Typically, the Origina l Equipme nt Manufacture r (OEM) will include detailed inspectio n instructio ns that you should follow following these high-load events. The objective of these instructions is to detect aircraft damage following an in-service flight or ground event.

While there are many conditio ns that can result in high-loads on the airframe and subsequent structural damage, we consider the use of flight data in your inspection process particularly beneficial for the events identified above.

(4) Your processes for evaluating these events should address:

(a) An appropriate indication that an event has occurred;

(b) An evaluatio n of the severity of the event; and

(c) Coordination with the manufacturer, as appropriate. Your special inspection procedures for high-load events should be robust enough to:

• Identify that a very high-load event has occurred,

• Assure that indicatio ns of structural damage are found in an initial inspectio n,

• Involve the OEM, if necessary,

• Provide a process for additional inspections that designed to identify all of the structural damage, and

• Provide a process for approval for return to service.

c. Technical Data that Describe Maintenance Standards, Methods, Techniques, and Proce dure s.

(1) Accomplishing Specific Tasks. This section of your manual concerns detailed procedures for accomplishing specific tasks. You should describe methods, techniques, technical standards, measurements, calibration standards, operational tests, structural repairs, etc., in this section. You should also include procedures for aircraft Weight and Balance (W&B), jacking, lifting and shoring, storage, cold weather operations, towing, aircraft taxi, and aircraft cleaning.

You can derive your maintenance manual contents from the manufacturer’s publicatio ns.

However, based on your particular service experience, organization, and operating context, the FAA expects you to continuo usly modify and customize your maintenance manual as necessary for the continuing success of your maintenance program. This is one of the desired outcomes of a well-functioning Continuing Analysis and Surveillance System (CASS), which we explain in more detail in Chapter 11 of this AC, and in the current edition of AC 120-79, Developing and Impleme nt i ng an Air Carrier Continuing Analysis and Surveillance System.

(2) Airworthine ss Dire ctive s (AD). You are required to accomplish the provisions of ADs that we issue by 14 CFR part 39. While not specifically required by any regulatio n, you should also includ e in your manual a process for managing ADs (i.e., evaluating, accomplishing, and verifying ADs). Your AD management process, as described in the current edition of AC 39-9, Airworthiness Directives Management Process, should include the following six elements: planning, support, provisioning, implementing, recording, and auditing. You may not Par 3-3 Page 9

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operate your aircraft that an AD applies to except in strict compliance with the provisions of the AD, so it is extremely important that you include in your AD process provisions that ensure:

• You review ADs for applicability to your aircraft;

• You accomplish the requirements of the AD within the timeframe specified in the AD;

• You keep records of the accomplishment and current status of each AD that applies to your aircraft; and

• You ensure that any subsequent maintenance or alteration to your aircraft does not remove the maintenance or alteratio n that was mandated by the AD.

(3) Removing AD Provisions. If you do subsequently remove the AD-mandated mainte na nce or alteratio n, you will be in violat io n of part 39 and may introduce an unsafe condition in your airplane. It would also make the required records for that particular AD inaccurate. If you determine that an alternative method of complia nce (AMOC) with an AD is necessary, you should refer to the current edition of FAA Order 8110.103, Alternative Methods of Compliance (AMOC). With regard to AD recordkeeping, see Chapter 8 of this AC for detailed information that deals with your maintenance recordkeeping system.

d. Work Cards. Work cards, sometimes referred to as job cards or task cards, while not a specific regulatory requirement, have evolved as a best practice. We consider work cards to be part of your air carrier manual and the air carrier maintenance program. They are the “what to do” and the “how to do it” parts of your maintenance program. You use work cards as a simple means of complying with maintenance performance and recordkeeping regulations. Your work cards provide a control element to the performance of maintenance. They also provide the means of ensuring that all maintenance personnel comply with your air carrier maintenance manual. It is an easy way for you to make sure that your maintenance personnel, as well as other personnel, are following your procedures. The second primary function is to document maintenance activities, providing a means for you to comply with your air carrier maintenance recordkeeping requirements. Work cards may also document the results of inspections, checks, and tests for data collection and analysis. The work-in-progress audits that you conduct regarding work card activit y as part of your CASS ensure that each individual who accomplishes work on your aircraft is following your manua l.

e. Contract Maintenance. If the air carrier chooses to use another person to perform mainte na nce for it, §§ 121.369(b)(10) and 135.427(b)(10) require that the air carrier’s manual includes policies, procedures, methods, and instructions for the accomplishment of all maintenance, preventive maintenance, and alterations carried out by a maintenance provider.

These policies, procedures, methods, and instructions must be acceptable to the FAA and provide for the maintenance, preventive maintenance, and alterations to be performed in accordance with the certificate holder’s maintenance program and maintenance manual.

NOTE: See Chapter 9 for more information regarding contract maintenance requirements.

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**CHAPTER 4. AIR CARRIER MAINTENANCE ORGANIZ ATION**

4-1. MAINTENANCE ORGANIZATION—GENERAL. Your maintenance organizatio n must be able to perform, supervise, manage, and amend your program; manage and guide your maintenance personnel; and provide the direction necessary to achieve your maintenance program objectives. Our regulatio ns require you to include a chart or a description of your maintenance organizatio n in your manual. You can read about maintenance organizatio n requireme nt s in 14 CFR part 121 subpart L, part 135 subpart J, and portions of part 119 subpart C. These organizatio nal regulatio ns apply to your organizatio n, as well as any other organizatio n that provides maintenance services for you. A chart is a good way to show your assignment of overall and direct authorities and responsibilities.

**4-2. REQUIRED MAINTENANCE ORGANIZ ATION MANAGEMENT POSITIONS.**

Part 119 subpart C includes specific requirements for maintenance management positions for operations under parts 121and 135. These are management positions required by the regulations.

However, you may need more management positions to administer and manage your maintenance organization. If necessary for your operation, you can ask the FAA for a deviation from the types and numbers of required part 121 or 135 management positions.

a. Part 121 Required Positions. For operations conducted under part 121, part 119, § 119.65(a) requires that each certificate holder have qualified personnel serving full-time in the Director of Maintenance (DOM) and Chief Inspector, or equivalent, positions. Section 119.67 defines the qualifications for these positions.

b. Part 135 Required Positions. For operations conducted under part 135, § 119.69(a) requires each certificate holder to have a qualified individ ua l serving in the DOM, or equivalent, position. Section 119.71(e) defines the qualifica t io ns for this position.

c. Managem ent Per sonnel. The regulatio ns require you to state the duties, responsibilities, and authority of each of your management personnel in your manual. You should state who has overall authority and/or responsibility, and who has direct authority and/or responsibility for a given process. Also, you must notify the FAA when you make changes in your part 119-required management personnel or when you have a vacancy in one of those positions.

NOTE: “Authority” means the power to design or change fundamental policy or procedures without having to seek higher level approval. Authority is permission; it is a right coupled with an autonomous power to accomplish certain acts or order others to act. Often one person grants another authority to act, such as an employer to an employee, a corporation to its officers, or a governmental empowerment to perform certain functions.

NOTE: “Responsibility” me ans the obligation to ensure a task or function is successfully carried out. Responsibility includes accountability for the action to carry out a task or function.

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**4-3. REQUIRED AIR CARRIER MAINTENANCE ORGANIZATIONAL STRUCTURE.**

a. Structure . Given the different types and sizes of air carriers, we wrote broad regulations in order to define an air carrier maintenance organization. A single means of compliance or a single organizational chart that would apply to all the different types and sizes of air carrier maintenance organizations is not possible.

b. Authority and Responsibility. You should designate an individ ual with the authority and the overall responsibility for managing and implementing your entire maintenance program, includ ing all inspectio n functio ns. The individ ual you designate must meet the qualificatio ns for the DOM listed in § 119.67(c) or § 119.71(e), as applicable. The inspectio n functio ns and the required inspection functions are part of your maintenance program.

c. Organizational Functions. The FAA recommends your maintenance organizatio n have three general organizatio nal functio ns to ensure that you conduct all operations to the highest possible degree of safety. If you are a larger organization, you may have different departments for each level, while in the smallest organizatio ns, you may carry out these functio ns through one or two individuals, maybe as a collateral duty. Generally, these three organizational functional levels include :

(1) Mechanics and/or inspectors performing the work at the first level (operations);

(2) Middle managers and supervisors at the second level (tactics); and

(3) The maintenance program accountable manager at the third level (strategy).

d. Position Descriptions. We expect you to assign clear authority and responsibility in your maintenance organizatio n, includ ing delegated responsibility, for the overall maintenance program and all of its elements and functions. You should include a position description that includes each position’s duties and responsibilities in your manual so that there is not a fragmented organizatio nal system with a high risk for confusio n over who is responsible for a given element, process, or task. Watch out for hidden duties and responsibilities where the duty and/or responsibility is shown in a process but not in the position description.

**4-4. SEPARATION OF INSPECTION AND MAINTENANCE DEPARTMENTS.**

a. Regulatory Requirements.

(1) If you perform maintenance (other than required inspections), §§ 121.365(a) and 135.423(a) require you to have an organizatio n that is adequate to perform maintenance work. Additionally, if you perform required inspections, §§ 121.365(b) and 135.423(b) require you to have an organizatio n that is adequate to perform required inspection work.

(2) Don’t confuse your maintenance production department with your maintenance organizatio n. Also, don’t confuse your inspectio n department, if you have one, with your required inspectio n organizatio n. We have defined “maintenance” in 14 CFR part 1, § 1.1 as “inspection, overhaul, repair, preservation, and the replacement of parts, but excluding preventive maintenance.” We do not define required inspection in § 1.1. However, within the Par 4-3 Page 12

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context of parts 121 and 135, the term “required inspection” has a very specific regulatory meaning, and should not be confused with the general use of the word “inspection” throughout the regulatio ns.

(3) While there is no regulatory requirement to separate the maintenance organization from the required inspection organization, there is a requirement when performing both maintenance and required inspection work to organize the performance of those functions so as to separate the maintenance function from the required inspection function.

b. Organization. Regulations require you to organize the performance of all maintenance functio ns, includ ing inspection, repair, overhaul, and the replacement of parts, to separate the functio n of required inspectio ns from the functio n of the other maintenance, preventive maintenance, and alteration activities. This organizational separation must be below the level of administrative control where you exercise overall responsibility for the required inspection functio ns, as well as the other maintenance, preventive maintenance, and alteration functions.

Consistent with subparagraph 4-3b, your accountable manager exercises overall authority and responsibility over the required inspection functions, as well as the other maintenance (includ i ng inspection), preventive maintenance, and alteration functions. See Figure 4-1, Maintenance Organizational Chart, for a representative organizatio nal chart.

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**FIGURE 4-1. MAINTENANCE ORGANIZATIONAL CHART**

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**CHAPTER 5. ACCOMPLISHMENT AND APPROVAL OF MAINTENANCE AND**

**ALTERATIONS**

**5-1. ACCOMPLISHMENT OF MAINTENANCE.**

a. Authority to Pe rform Maintenance. As a maintenance entity, you have authorizatio n under 14 CFR part 43, §§ 43.3(f) and 43.7(e); part 121, § 121.379; and part 135, § 135.437 to perform maintenance on your own air carrier aircraft and to approve them for return to service without obtaining any other maintenance certificatio n. In addition, §§ 121.379 and 135.437 provide clear authority for you, under your air carrier certificate, to perform maintenance on behalf of other air carriers who conduct operations under the same part as you do.

b. Cer tificate Requir em ents.

(1) Each individ ual who makes an airworthiness determinatio n on your behalf must hold an appropriate airman’s certificate. Sections 121.378 and 135.435 require that any individ ual who you put directly in charge of performing maintenance hold an airman certificate.

Section 121.371 requires that any individual that you authorize to perform Required Inspection Items (RII) for you hold an appropriate airman certificate. Section 121.709 requires that anyone who you authorize to issue an approval for return to service hold an appropriate airman’s certificate. Your Director of Maintenance (DOM) and chief inspector must hold an airman’s certificate with Airframe and Powerplant (A&P) ratings.

NOTE: The certificate requirements contained in the regulations stated above are dir ected at the air carrie r. The certificated airman acting in this position does not exercise the authority or privileges of his or her certificate.

(2) You accomplish all maintenance and approval for return to service on your aircraft under your air carrier certificate by your maintenance organizatio n or persons authorized by you, not by any individ ual or organizatio n under their own individual certificate. There is, however, one exception to the individual airman certificate requirement. It occurs if you arrange for a certificated repair station (CRS) located outside the United States to perform maintenance. At such repair stations, individuals directly in charge of performing maintenance or required inspections are not required to hold an FAA airman certificate.

5-2. MAJOR REPAIRS AND ALTERATIONS. Under §§ 121.379(b) and 135.437(b), major repairs and alterations must be done in accordance with technical data approved by the FAA.

Title 14 CFR, part 43, appendix A, contains a list of repairs and alterations that are considered to be major. However, exclusive reliance on the part 43, appendix A, list of major repairs and alterations to make the major/minor classification might result in the misclass if ica t io n of some repairs and alterations because the part 43, appendix A, list does not include evolving airplane design and constructio n techniques, such as composite structures and the high-speed, high-altitude pressurized jet transport. You should have detailed major/minor classification procedures in your manual to evaluate each repair or alteration on a case-by-case basis, using such factors as the certification basis of the aircraft; classification of the structure as primary, secondary, or a primary structural element; or classification as a fail-safe, safe- life, or damage-tolerant structure.

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5-3. AIRWORTHINESS RELEASE FORM OR AIRCRAFT LOG ENTRY AND APPROVAL FOR RETURN TO SERVICE. After performing any maintenance, preventive maintenance, or alterations on your airplane, you must approve it for return to service before you may operate it. As an air carrier, you must issue an approval for return to service under § 121.709 or § 135.443, as appropriate. You can read additional, more detailed information about the process for approving your airplanes for return to service in Chapter 8.

5-4. SCOPE OF MAINTENANCE. You must provide instructio ns in your maintenance program and maintenance manual for maintenance and alterations. These instructions should address the areas of what to do, when to do it, how to do it, and whether it was done properly.

The three major areas to consider are scheduled maintenance, unscheduled maintenance, and specific maintenance requirements for major components of the aircraft.

a. Scheduled Maintenance. Scheduled maintenance consists of all the individual maintenance tasks performed according to the maintenance time limitations, also called a mainte nance schedule. Your scheduled maintenance activities should include procedural instructions for the maintenance tasks and procedures for recording the results of the inspectio ns, checks, tests, and other maintenance. Your procedures should also provide for time-related activities such as recurring Airworthine ss Directive s (AD), Certification Maintenance Requireme nts (CMR), and life-limited parts retirement.

b. Unscheduled Maintenance. Unscheduled maintenance includes procedures, instructions, and standards for maintenance that occurs on an unscheduled or unforeseen basis. A need for unscheduled maintenance may result from scheduled maintenance tasks, pilot reports, or unforeseen events, such as high-load events, hard or overweight landings, tail strikes, ground damage, lightning strikes, or an engine over-temperature. In your maintenance manual, you should include instructio ns and standards for accomplishing and recording unscheduled maintenance.

c. Specific Maintenance Requirements for Major Aircraft Components.

(1) Engine Maintenance Program. Your engine maintenance program should cover the maintenance of installed engines and off-wing engines for each engine model you operate. If your aircraft has auxiliary power units (APU), you may want to include APU maintenance as part of your engine maintenance program. Usually, the installed engine or APU requirements will be contained in the mainte nance schedule. In addition to procedural information, the off-wing program described in your maintenance manual should provide shop scheduling infor mat io n or interva ls for cleaning, adjusting, inspecting, testing, and lubricating each part of the engine or APU. You should include in your maintenance manual the degree of inspectio n, the applicable wear tolerances, and the work required when the engine or APU is in the shop.

(2) Propeller Maintenance Program. If applicable, your propeller maintenance program should cover the maintenance of installed propellers and off-wing propellers for each model you operate. Usually, the installed propeller system scheduled maintenance requirements will be contained in the maintenance schedule. In addition to procedural information, the off-wing program described in your manual should provide shop scheduling information or interva ls for cleaning, inspecting, adjusting, testing, and lubricating each part of the propeller Par 5-3 Page 16

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system requiring that maintenance. You should include in your maintenance manual the degree of inspection, the applicable wear tolerances, and the work required at these periods. Some modern propellers are constructed of composite materials and, therefore, may require unique tools, repair procedures, and specialized training for your maintenance personnel.

5-5. PARTS AND APPLIANCES MAINTENANCE PROGRAM. For the most part, this section of your maintenance program covers shop operations, which may include both scheduled and unscheduled tasks. You may conduct these shop operations at some location other than where you perform maintenance on your aircraft. Your parts and appliance maintenance program should cover both installed parts and appliances, and off-wing maintenance for each part and appliance model that you operate. Usually, the scheduled maintenance requirements for installed parts and appliances will be contained in the maintenance schedule. In addition to procedural informatio n, the off-wing program described in your maintenance manual should provide shop scheduling informatio n or intervals for cleaning, adjusting, inspecting, testing, and lubricating each component of the part and appliance requiring that maintenance. Include in your maintenance manual the degree of inspection, the applicable wear tolerances, and the work required when the part or appliance is in the shop.

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**CHAPTER 6. MAINTENANCE SCHEDULE**

6-1. THE MAINTENANCE SCHEDULE. Title 14 CFR part 119, § 119.49 and part 121, § 121.135(b) require you to have maintenance time limitations, also called a maintenance schedule. These same rules permit you to use standards for determining your maintena nc e time limita t io ns, which are the regulatory basis of FAA-approved reliability programs. The maintenance time limitatio ns set out the what, how, and when of your scheduled maintenance effort. Although in the past the schedule includ ed only basic overhaul limits and other general requirements, today it includes a specific list of each individual maintenance task and its associated interval. The regulations are broad enough to permit you to organize all of these individual tasks into a series of integrated scheduled work packages of your own design that provide a continuous succession of necessary or desirable scheduled maintenance tasks for your entire airplane.

NOTE: You should not confuse the meaning of the terms “instructions for continued airworthiness” (ICA), required by 14 CFR part 25, § 25.1529, “time limitations” (maintenance schedule), required by § 121.135(b)(18), and “airworthiness limitations” (AL) required by part 25, appendix H, § H25.4.

Although related, each term has a significant meaning within the context of the stated part and section of the regulation.

6-2. THE FAA’s ROLE IN RELATION TO THE MAINTENANCE SCHEDULE. The FAA authorizes your maintenance schedule through your operations specifications (OpSpecs), and your Continuing Analysis and Surveillance System (CASS) monitors that schedule to verify its effectiveness (i.e., producing the desired results). Your CASS will be your principal source of informatio n that might indicate a needed change to your maintenance schedule. (We describe the CASS in Chapter 11 and in much more detail in the current edition of AC 120-79, Developing and Impleme nt i ng an Air Carrier Continuing Analysis and Surveillance System.) We expect you to correct any deficiencies in your maintenance schedule. Under § 121.373(b) and 14 CFR part 135, § 135.431(b), if you do not make needed changes, we can require you to change your maintenance schedule or any other element of your maintenance program found deficient.

**6-3. MAINTENANCE SCHEDULE CONTENTS.**

a. Maintenance Schedule Should Contain the Following Information:

(1) What (Unique Identifier). This is the item that you are going to maintain. Your identifier should be specific enough to allow the individ ual that you assign to do the scheduled maintenance task to easily and accurately identify the item. The following are examples of items that an operator’s maintenance schedule may include:

• Airworthiness Directives (AD),

• Service Bulletins (SB)/Service Letters (SL),

• Replacement of life-limited items,

• Replacement of components for periodic overhaul or repair,

• Special inspections,

• Checks or tests, Par 6-1 Page 19

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• Lubricatio n and servicing,

• Tasks identified in the Maintenance Review Board Report (MRBR),

• ALs,

• Certification Maintenance Requirements (CMR),

• Supplement a l Structural Inspection Documents (SSID), and

• Electrical wiring interconnection system (EWIS).

(2) How (Task). This is how you should maintain the item you are going to maintain, or the scheduled maintenance task you will perform. A scheduled maintenance task is a maintenance action that you perform at regular, scheduled intervals. The intent of this task is to ensure the item can continue to perform its intended functio n, allows you to discover a hidden failure, or to ensure that a hidden function is available. You should not use terms such as “hard-time (HT),” “on-condit io n,” or “conditio n monitored” in your maintenance schedule. The maintenance schedule should state the maintenance task to be performed to meet the requirement

(e.g., Replace, Inspect, and Test).

(3) When (Timing). You should accomplish scheduled maintenance tasks (one-time or repetitive) at an acceptable time in service. You may measure time in service in calendar-time, operational hours, flight cycles, or any other appropriate parameter.

b. Maintenance Schedule Objective. Your overall maintenance schedule objective is to do the correct tasks at the correct interval. Keep in mind that more maintenance is not always a good idea, so if you decide to decrease intervals or add tasks, you should go through the same justification process as any other change to the maintenance schedule.

c. Maintenance Schedule Best Pr actice. For task management, invento ry, and audit purposes, you should identify on the maintenance schedule the task or work card associated with each scheduled maintenance task. This way you can ensure that you accomplish all of your scheduled maintenance tasks according to your schedule.

6-4. STANDARDS FOR DETERMINING MAINTENANCE SCHEDULES. As we mentioned in paragraph 6-1, §§ 119.49 and 121.135 permit you to have standards for determining your maintena nc e time limita t io ns. In the past, we used this language as the regulatory basis for FAA-approved reliability programs that evolved during the 1960s. These programs were based on the Air Transport Association of America’s (ATA) now obsolete process-based Maintenance Steering Group—2nd Task Force (MSG-2) decision logic that focused on failure rates and maintaining individual parts of the aircraft. Consistent with the continuo us evolutio n of aviatio n, MSG–2 became obsolete in 1980 with the advent of the ATA’s task-based Maintenance Steering Group—3rd Task Force (MSG-3) decision logic. MSG-3 focused on aircraft systems and a loss of functio n rather than on an individ ua l part failure. In any case, the management of these MSG-2 process-based programs was actuarial analysis.

Air carriers used the failure rates of a part to determine, through a probability process, the likelihood that the part would have a similar failure rate in the future. The standard was the acceptable failure rate. Air carriers used a failure rate alert program with upper control limits (UCL) and lower control limits (LCL) to track part failure rates. The air carrier was obliged to take action only when the failure rate deviated from the probability-based prediction Par 6-3 Page 20

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(i.e., exceeded the UCL or the LCL). If the part did not respond, the air carrier had authorizatio n to move the UCL or LCL to make the failure rate fall within the alert program limit s.

a. Reliability Center ed Maintenance (RCM). During the 1970s, after collecting a large amount of operational data over time, the industry came to the realization that using failure rates and alert programs was not the most effective way of managing scheduled maintenance. Using the vast amount of operational data that was available, United Airlines, Inc. (UAL) developed and published a report during 1978 under a U.S. Department of Defense (DOD) contract entitled “Reliability Centered Maintenance (RCM).” This very significant document’s conclusio ns determined the flaws of the previous focus on part failure rate. RCM focused on the loss of function of an aircraft system. RCM determined that everything does not fail the same way;

failures occur according to six different failure patterns. RCM also determined that everything does not require the same type of maintenance; there are four different types of scheduled maintenance. RCM also took into account the different consequences (safety, operational, and economic) of a loss of functio n, as well as system functio nal redundancy and inherent design safety, when determining if scheduled maintenance was required. In some cases, RCM determined that no scheduled maintenance was required. This resulted in doing only required maintenance and a much lower maintenance burden.

b. MSG–3 Decision Logic. The RCM document was the major basis for the ATA’s development of the MSG-3 decision logic in 1980. Since then, most aircraft manufacturers have used the ATA’s MSG-3 decision logic to help them develop scheduled maintenance requirements for their new products. Besides providing organization and flow to the deliberative process, the primary attribute of the MSG-3 process is that the user can develop initial scheduled maintenance requirements without the operational data that is required to determine the need for scheduled maintenance tasks. Using the techniques of the MSG-3 decision logic, it is fairly simple to decide what tasks are required to be included in an initial scheduled maintenance program. However, the MSG-3 decision logic does not contain task interval selection decision logic to help the user determine where to set the task intervals, or how to adjust them after service is init iated. Using the MSG-3 process, initial task intervals are set on the basis of knowledge of the design, and the best judgment of the MRBR working group members. As a result, validat io n of initial interval selections must occur when the aircraft begins service and starts generating the operational data that was not available when the initial intervals were set.

c. Effective Scheduled Maintenance. An inherent functio n of your CASS is to determine the effectiveness of your scheduled maintenance effort through operational data collection and analysis activity. You use this important functio n to determine the level of scheduled maintenance effectiveness and to make the changes necessary to achieve the standard of effectiveness that you have set. Effective means “it is producing the desired results.” Thus, from an operational standpoint, an indicator of effectiveness of your scheduled maintenance effort is the availability of your aircraft for flight operations. If your aircraft are unavailable for flight operations due to maintenance reasons, then your scheduled maintenance program may not be as effective as it should be. There may be other elements of your maintenance program besides the scheduled maintenance element that may be deficient as well, but your CASS procedures will identify the root cause, and help you identify and make the adjustments/changes necessary to achieve the level of flight operations availability (the result) that you have set.

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d. MRBR Changes. MRBR revisions are developed to address global in-service experience in addition to reflecting new design configurations and new rules. Therefore, when MRBR revisions occur, you should review them and determine if they necessitate a change in your maintenance schedule based on your particular needs, experience, and program’s goals and philosophy.

NOTE: A revision to the MRBR alone does not automatically constitute an approval basis for an air carrier to change its existing maintenance schedule.

e. Failure Effect Categories (FEC). While you may make changes to your maintenance schedule, it is important for you to consider the task FEC that arises from application of the MSG-3 logic used to develop the MRBR (since this helps identify the relative criticality of the task). You should not delete or change the scope of MSG-3 FECs 5 (Evident Safety) and 8 (Hidden Safety) tasks without the concurrence/approval of the FAA Maintenance Review Board (MRB) Chairman and the Original Equipment Manufacturer (OEM)/type certificate holder (TCH).

NOTE: To protect the identity and significance of a safety-related task, you should identify each task in your maintenance schedule that is a CMR, AL, or those with FECs 5 and 8.

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**CHAPTER 7. REQUIRED INSPECTION ITEMS**

7-1. R equired Inspection Items (RII).

a. Tasks as RIIs. Title 14 CFR part 121, § 121.369(b) and part 135, § 135.427(b) require you to designate certain tasks as RIIs. Your RIIs must include at least those tasks that could result in a failure, malfunction, or defect that endangers the safe operation of the aircraft if the task is not completed properly or if you use improper parts or material. If other persons perform maintenance tasks for you, you may authorize them to accomplish your RII requirement, provided that your manual satisfies the regulatory requirements, as outlined in paragraph 7-2.

Consistent with the regulatio ns, you remain primarily responsible for the performance of each RII accomplished by the other person. When another person performs RII to include the entire aircraft, this is considered Essential Maintenance.

NOTE: See Chapter 9 for more information on Essential Maintenance .

b. Making RII Lists. Your RII lists should identify specific items of maintenance for each aircraft type you operate. It is inappropriate to designate entire systems as RIIs. You should adhere to a decision process, similar to the following, when creating a list of RIIs:

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FIGURE 7-1. REQUIRED INSPECTION ITEMS Required Inspection Item (RII)

Is a required test performed on the item that will simulate operational functions and defect failures, malfunctions or defects that would impact the safe flight or landing of the aircraft?

No No Yes Identify a task that that could result in a failure, malfunction, or defect endangering the safe operation of the aircraft, if not performed properly or if improper parts or materials are used Yes Yes No Designate task as a Required Inspection Item RII does not apply as system operational integrity can be assessed.

RII does not apply as those lists contain items of equipment which the Administrator has determined may be inoperative or removed while still maintaining aircraft airworthiness RII does not apply as it is limited to installations and repairs on aircraft Is the item potentially deferrable per the minimum equipment list (MEL) or Configuration Deviation List (CDL)?

Is work being performed on the Aircraft?

Yes Par 7-1 Page 24

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c. RIIs and Safety. RIIs relate directly to flight safety. Consider all your RIIs with the same safety of flight consideration and emphasis even if accomplis hing an individ ua l RII adversely impacts your flight schedule, it is related to a scheduled or an unscheduled task, or it arises at an awkward time or at an inconvenient location.

**7-2. RII PROCEDURES, STANDARDS, AND LIMITS.**

a. List of Other Persons. Your manual must includ e a list of persons with whom you have arranged for the performance of any required inspections (§§ 121.369(a) and 135.427(a)), both within your organizatio n and within other organizatio ns that perform maintenance on your behalf. This listing must include a designatio n by occupational title of the personnel authorized to perform each required inspection (§§ 121.369(b)(3) and 135.427(b)(3)).

b. Certification. With consideration of the exception at §§ 121.378(a) and 135.435(a), each individ ua l that you grant an RII authorizatio n to must hold an appropriate airman’s certifica te. This is an air carrier qualification requirement; the individual does not exercise that certificate when accomplishing the RII. You must formally notify each of these individ ua ls of their RII authorization as well as its scope (§§ 121.371(d) and 135.429(e)).

c. RII Requirements. You should clearly identify your RII requirements on work forms, job cards, engineering orders, etc., or by any other method consistent with your maintenance program. A primary concept of the RII functio n is to prevent any person who performs any item of work from performing any required inspection of that work (§§ 121.369(b)(7) and 135.427(b)(7)). Therefore, it is important that you identify RIIs whenever possible so that everyone knows that an RII is required. You should also clearly state RII buy-back procedures (§§ 121.369(b)(4) and 135.427(b)(4)).

d. Standards and Limitations. You must set procedures, standards, and limits necessary for required inspectio ns, and acceptance or rejection of the RII (§§ 121.369(b)(5) and 135.427(b)(5)). You should have those procedures, standards, and limits necessary for the accomplishment of your required inspections. You must also have those procedures, standards, and limits necessary for the acceptance or rejection of each of your RIIs. As you will not find RIIs or procedures, standards, and limits for RIIs in an Original Equipment Manufacturer (OEM) manual, you will have to develop these and put them in your manual. Your manual must specify the method of performing required inspections (§§ 121.369(b)(3) and 135.427(b)(3)).

e. Proce dure s. Your manual must include procedures to ensure that you perform and complete all required inspections (§§ 121.369(b)(6) and 135.427(b)(6)) before you release the aircraft to service (§§ 121.369(b)(9) and 135.427(b)(9)).

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**CHAPTER 8. MAINTENANCE RECORDKEEPING SYSTEM**

8-1. REASONS FOR MAKING AND KEEPING MAINTENANCE RECORDS. Your primary reason to make and retain air carrier maintenance records is to show that the U.S. standard airworthiness certificate on your aircraft is effective and that your aircraft is Airworthy. A U.S. standard airworthiness certificate is effective only as long as the maintenance and alterations are performed according to the requirements of the FAA’s regulations. If your required aircraft maintenance records are incomplete or inaccurate, it can render your aircraft’s U.S. standard airworthiness certificate ineffective. Maintenance actions, in almost all cases, become intangible or abstract after the fact. Therefore, in order for you to make a maintenance action tangible, you must make a record of that maintenance action. Additionally, making a record of certain summary informatio n supports identificatio n of the current inspectio n and airworthiness status of your aircraft.

8-2. PART 43 REQUIREMENTS. You can find the basic requirement to make a maintenance record in 14 CFR part 43, § 43.9(a); however, § 43.9(b) indicates that the governing requirements for you, an air carrier, are found in 14 CFR part 121 or 135. That is another way of saying that the recordkeeping requirements of § 43.9(a) do not apply to you. However, the requireme nt s of § 43.9(b) are consistent with the air carrier maintenance recordkeeping requireme nt s of part 121, §§ 121.369(c) and 121.380(a) and (c), or part 135, §§ 135.427(c) and

135.439.

**8-3. WORK PERFORMED BY A PART 145 CERTIFICATED REPAIR STATION (CRS).**

a. Retaining Records. Title 14 CFR part 145, § 145.219 sets forth requirements for a CRS to retain certain records of maintenance that it performs. It also requires the repair station to make those records available to the FAA. However, these §§ 43.9(a) and 145.219 requirements do not apply when the repair station is accomplis hing any work on your aircraft.

b. Copies of Records. The wording of the § 145.205 regulations, as well as 14 CFR part 119, § 119.1(c), and §§ 121.1(b), and 135.1(a)(2), compel a part 145 CRS to follow the procedures and requirements of your maintenance program and applicable sections of your maintenance manual when accomplishing any maintenance or alterations on your aircraft.

Consequently, a CRS must use the performance standards of part 121 or 135, including the recordkeeping requirements, instead of following the provisions in part 145 and the repair station’s Repair Station Manual (RSM). This is consistent with the requirements of the Paperwork Reduction Act, which does not permit the government to require two separate but identical sets of records. The responsibility for retaining records in accordance with the retention requirements of §§ 121.380(c) and 135.439(b) rests with you, the air carrier, not the repair station. However, if a part 145 repair station wants to retain a copy of those records generated by working on your aircraft, our regulatio ns do not preclude them from doing so. Asking the part 145 repair station to keep your records for you is consistent with regulatio ns, although you are responsible for retaining them and making them available to the FAA. This is consistent with the requirements of § 119.59(c).

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**8-4. AIR CARRIER MAINTENANCE RECORDKEEPING.**

a. Maintenance Records are Important For:

(1) The air carrier, in fulfilling its responsibility to determine, validate, and maintain the airworthiness status of its aircraft; and

(2) The FAA, for use during a continuing review of aircraft maintenance records as a direct means of determining the airworthiness and safety status of air carrier aircraft.

b. Review ing Maintenance Recor ds. Because reviewing maintenance records is often the only direct means of determining the accomplishment of required maintenance, Federal law treats the act of intentionally failing to make and keep, as well as the act of intentionally falsifying, mutilating, or altering air carrier aircraft records, as a criminal act subject to the imposit io n of substantia l fines and/or impriso nme nt.

**8-5. MAKING AND KEEPING REQUIRED RECORDS.**

a. Recor dkeeping System . FAA regulatio ns (§ 121.369(c) or § 135.427(c)) require you to have and use a recordkeeping system for the preservation and retrieval of all work performed on your aircraft. You must document your system in your maintenance manual. The primary objectives of these systems are the generation, storage, retention, and retrieval of accurate and complete air carrier aircraft maintenance records. As stated earlier, these records are primarily made to show that the U.S. standard airworthiness certificate of your air carrier aircraft is effective, and that your aircraft is Airworthy and capable of safe flight.

b. Record Locations. FAA regulatio ns (§ 119.59(b)(1)(ii)) also require you to make and keep a listing that identifies the location of each record, document, and report that you are required to make and keep, as well as a listing that identifies each person that is responsible for each of those records, documents, and reports.

c. Airworthine ss Dire ctive s (AD). FAA regulatio ns (§§ 121.380(a)(2)(vii) and

135.439(a)(2)(v)) also require you to keep a record of the current status of applicable ADs, includ ing the date and methods of compliance, and, if the AD involves recurring action, the time and date when the next action is required.

8-6. REQUIRED AIR CARRIER MAINTENANCE RECORDS. Current requirements found in §§ 121.380 and 135.439 call for two types of records: a list of current status infor mat io n, and air carrier airworthiness release form records.

8-7. WHEN TO MAKE RECORDS AVAILABLE TO THE FAA. Section 119.59(c) mandates that you must make your air carrier maintenance records available to us. We can require you to make your records available to us at any time.

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**8-8. RESPONSIBILITY FOR MAKING RECORDS AVAILABLE TO THE FAA.**

Under § 119.59(b)(1), you must make a list of persons in your organization that you have designated to be responsible for making each required maintenance record, document, or report available to the FAA upon request. You must make a list of the location of each record, document, or report. You must keep this list current and make it available to the FAA at your principal base of operations.

8-9. REQUIRED RECORDS. You are required to make and keep certain current status records. Current status recordkeeping requirements are listed in §§ 121.380 and 135.439 and explained as follows :

a. Total Time in Service. The total time in service of the airframe, each installed engine, and each installed propeller is a record that contains the time in service accrued since new or rebuilt, expressed in hours, landings, or cycles.

NOTE: It is important for you to know that “rebuilt” does not have the same meaning as “overhauled” (§ 43.2(b)).

b. Current Status of Each Life-Limited Part. The current status of each life-limited part of each airframe, engine, propeller, and appliance means a record that contains at least the following information:

(1) Time in service since new, expressed in the appropriate parameter (e.g., hours, cycles, calendar-time);

(2) The time in service remaining to the specified life limit expressed in the appropriate parameter (e.g., hours, cycles, calendar-time);

(3) The specified life limit expressed in the appropriate parameter (e.g., hours, cycles, calendar-time); and

(4) A record of any action that alters the part’s life limit or changes the parameter of the life limit.

NOTE: If you conduct operations under part 135, total time in service and the current status of life-limited parts also includes rotors.

c. Time Since Last Overhaul. The listing of the time since last overhaul means a record that contains at least the following information:

(1) An identification of the item that requires overhaul and its associated scheduled overhaul interval;

(2) The time in service since the last overhaul was accomplished;

(3) The time in service remaining until the next scheduled overhaul is due; and

(4) The time in service when the next scheduled overhaul is due.

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NOTE: The listing of time since last overhaul refers to summary current status information. You must not confuse it with an overhaul record, which is a description of the work performed and the identification of the person who performed and/or issued the approval for re turn to se rvice.

d. Current Inspection Status of the Aircraft. The current inspection status of the aircraft means a record that contains at least the following information:

(1) A listing identifying each of the scheduled inspection packages, and each task and their associated intervals required by the maintenance program under which the aircraft is mainta ined ;

(2) The time in service accrued since the last accomplishment of each of the scheduled inspection packages and tasks required by the maintenance program under which the aircraft is mainta ined ;

(3) The time in service remaining until the next accomplishment of each of the scheduled inspection packages and tasks required by the maintenance program under which the aircraft is maintained; and

(4) The time in service when the next accomplishment of each of the scheduled inspection packages and tasks required by the maintenance program under which the aircraft is mainta ined is due.

e. Current Status of Applicable ADs. The current status of applicable ADs means a record that contains at least the following infor mat io n:

(1) Identification of the particular airframe, engine, propeller, appliance, or component to which the AD applies;

(2) The AD number (and/or regulatory amendment number);

(3) For new ADs, the time when the AD action is due, expressed in the appropriate parameter (e.g., hours, cycles, calendar-time);

(4) The date when the required action was accomplished and the time in service expressed in the appropriate parameter (e.g., hours, cycles, calendar-time);

(5) If the requirement is recurring or not due yet, the date when the next action is due, and the time in service expressed in the appropriate parameter (e.g., hours, cycles, calendar-time); and

(6) With regard to an AD, the method of compliance means a concise description of the action taken to comply with the requirements of the AD. If the AD or its referenced manufacturer’s service bulletin (SB) permits the use of more than one method of compliance, the record must include a reference to the specific method of compliance used. If you use an alternative method of compliance (AMOC) to comply with an AD, the method of compliance means a description of the AMOC and a copy of the FAA approval.

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NOTE: You should not confuse the current status listing of an AD or me thod of compliance with an AD record of accomplishment, which is a description of the work and who performed it and/or issued the approval for re turn to se rvice. They are two separate and distinct records.

f. Current Major Alterations of Each Airframe, Engine, Propeller, and Appliance.

A listing means a record that contains at least the following information:

(1) A listing identifying each major alteration, as well as the associated item that has been altered; and

(2) A description of, or reference to, the FAA-approved technical data that you used to make the major alteration.

NOTE: If you conduct operations under part 135, you must include in this listing all current major repairs, as well as major alterations, and you must include major repairs and major alterations to each rotor.

NOTE: The listing of the current major alterations refers to summary current status information. You must not confuse this with a major alteration report, which is a description of the work performed, a description of the FAA-approved technical data used to make the major alteration, and the identification of the individual who performed and/or issued the approval for re turn to se rvice. You must not confuse this listing with the requirement to submit a copy of each report of a major alteration to the FAA. There are two different requirements—one for a major alteration current status listing, and one for a report for each major alteration that you accomplish.

g. Airworthine ss Re le ase Form. All the records necessary to show that all requirements for the issuance of an Airworthiness Release Form have been met. These records support the use of an Airworthiness Release Form, which is not part of the aircraft maintenance logbook. While the regulatory requirement for these records does not provide a detailed list of these records, this requireme nt is generally accepted to mean:

(1) Detailed records of all scheduled maintenance that has not been superseded by work of equivalent scope and detail;

(2) Detailed records of the last overhaul for items that required an overhaul;

(3) Detailed records of all unscheduled maintenance that has not been superseded by work of equivalent scope and detail; and

(4) Copies of the Airworthiness Release Form covering the last 60 days of operation.

8-10. OTHER REQUIRED RECORDS AND REPORTS. The FAA regulatio ns require you to make other reports and records as discussed in this paragraph. You can use these records and reports to review your maintenance operations to determine the adequacy of the maintenance portion of your air carrier manual and the effectiveness of your CAMP. These records are one of Par 8-9 Page 31

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the sources of informatio n for your Continuing Analysis and Surveillance System (CASS). The FAA also uses these reports in its continuo us oversight of your maintenance program activities.

a. Maintenance Log. Sections 121.701 and 135.65 require any person who takes action in response to a reported or observed failure or malfunction to make a record of that action in the maintenance log of the aircraft. These air carrier maintenance log entries correspond to the maintenance recording requirements of § 43.9(b). You also must ensure that each pilot in command (PIC) ensures that all mechanical irregularities occurring during flight time are entered in the maintenance log at the end of that particular flight time, consistent with §§ 121.563 and 135.65.

b. Airworthiness Release Form or Log Entry.

(1) Your Airworthiness Release Form or Log Entry required by § 121.709 or § 135.443 corresponds to the approval for return to service requirements of §§ 43.5, 43.7(e), 121.379(b), and 135.437(b). Furthermore, parts 121 and 135 require you to prepare either an Airworthiness Release Form or a log entry before you can operate your air carrier aircraft after you perform any maintenance, preventive maintenance, or alterations, whether you operate the aircraft in air transportation or not.

(2) Your approval for return to service certification and documentation required by § 121.709 or § 135.443 is a singular requirement, but you may execute it in one of two ways:

(a) You may complete an Airworthiness Release Form and give it to the PIC. If you use an Airworthiness Release Form, you must keep it separate and distinct from the aircraft log.

It is not included in the maintenance record requirements. The separate and distinct requirement corresponds to the requirements in §§ 121.380(a)(1) and 121.709(d). In modern day environments, you are most likely to use the log entry method to comply with § 121.709 or § 135.443. Other than form or format, there is no legal or technical difference between an Airworthiness Release Form and a log entry.

(b) If you make a log entry, you do not have to issue an Airworthiness Release Form. To avoid confusio n and to be consistent with the regulatio ns, you should not identify this entry in the aircraft log as an airworthiness release. We understand that few air carriers use a separate Airworthiness Release Form.

(3) Consistent with §§ 121.709(d) and 135.443(d), you may include a statement in your manual that the signature in the aircraft log of an authorized, appropriately certificated individual constitutes an approval for return to service under your air carrier maintenance program. Such an authorized signature constitutes the four air carrier approvals for return to service certifications without restating each one of the certifications. You must prepare your Airworthiness Release Form or log entry in accordance with procedures in your manual and must include the following four certificatio ns consistent with statutory consideratio ns for operations with the highest degree of safety in the public interest:

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(a) The work was performed in accordance with the requirements of your manual;

(b) All items required to be inspected were inspected by an authorized person who determined the work was satisfactorily completed;

(c) No known conditio n exists that would make the aircraft unairworthy; and

(d) So far as the work performed is concerned, the aircraft is in condition for safe operation.

(4) The Airworthiness Release Form or log entry must be signed by an appropriately certificated individual who is authorized by you to make the Airworthiness Release Form or log entry on your behalf.

NOTE: The Airworthine ss Release Form or log entry must be accomplished by an authorized mechanic or repairman on your behalf under your part 121 or 135 certificate authorizations. This is consistent with the requirements and authorizations of § 43.7(e), 121.379(b), or 135.437(b), and § 121.709(b)(3) or 135.443(b)(3).

NOTE: Consistent with regulations, no individual may issue an Airworthine ss Re le ase Form or make a maintenance log entry unless you have authorized them.

(5) Your maintenance manual should include detailed procedures for accomplishing the Airworthiness Release Form or log entry after you accomplish any maintenance on your aircraft.

Your procedures should include processes designed to ensure that you do not operate your aircraft after any maintenance, preventive maintenance, or alteration is accomplished, unless you complete the Airworthiness Release Form or maintenance log entry.

(6) Your maintenance manual should include detailed procedures for qualifying and authorizing each individ ual that you use to accomplish your § 121.709 or 135.443 Airworthiness Release Form or log entry. These procedures should include a positive, readily available means for you to document and transmit the authorizatio n to the individ ual, includ ing the scope and limitations of their authorization.

c. Service Difficulty Reports (SDR). You are required to make SDRs by §§ 121.703 and 135.415. While analysis of these reports can help your CASS identify deficie nc ies within your maintenance program, these reports are also our primary means of gathering information for our Service Difficulty Reporting Subsystem (SDRS).

d. Mechanical Interruption Reports. We require you, under §§ 121.705 and 135.417, to make mechanical interruption reports. These reports document those instances when there is an interruptio n to one of your flights, unscheduled change of aircraft en route, or unscheduled stop or diversion from a route caused by known or suspected mechanical difficulties that are not required to be reported under the SDR reporting requirements of § 121.703. You are also required to report the number of engines that you removed prematurely because of malfunction, failure, or defect, listed by make, model, and the aircraft type in which it was installed. If you Par 8-10 Page 33

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operate aircraft with propellers, you must report the number of propeller featherings in flight, listed by type of propeller, and engine and aircraft on which it was installed. You do not need to report propeller featherings for training, demonstration, or flight check purposes. This is a prime indicator of deficiencies in the effectiveness of your maintenance program. Moreover, Root Cause Analys is (RCA) of these events is one of your most useful means of oversight of the level of effective ne ss of your maintenance program.

**8-11. REQUIREMENTS FOR REPORTS OF MAJOR ALTERATIONS AND MAJOR REPAIRS.**

a. Part 121 Major Repair and Major Alteration Reports. If you conduct operations under part 121, § 121.707 requires you to make a report of each major alteration and major repair. You must submit the major alteration report to us, and you must make the major repair report available to us for inspection. This falls under § 119.59 requirements. In addition, because you are an air carrier, you do not have to use FAA Form 337, Major Repair and Alteration (Airframe, Powerplant, Propeller, or Appliance), to report a major alteration or major repair that you or an MP accomplished.

b. Part 135 Major Repair and Major Alteration Reports. If you conduct operations under part 135, there is no requirement that requires you to submit reports of major alterations or major repairs. However, while a report is not required, the records of aircraft maintenance or alteration are required and you must make them available to us when we ask for them.

NOTE: You should not confuse these alteration and repair reports with the current status listing of major alterations required under part 121 or the current status listing of major repairs and alterations required under part 135.

8-12. REQUIREMENTS FOR HISTORICAL OR SOURCE RECORDS. You do not have to keep historical or source records to prove that your required records, such as current status records that you must make, keep, and make available to the FAA, are true and accurate.

Inherent with the requirements and objectives of your air carrier maintenance program, you must have a system to prepare, store, and retain your required maintenance records; you must monitor that system under your CASS to ensure that you are following your procedures and that they are effective. This ensures that your required records are true and accurate. Records such as the in-service history of life-limited parts (traceability back to birth) or the record of accomplishment of an AD do not need to be kept indefinitely. However, remember there are severe crimina l penalties for falsifying or failing to make or keep air carrier records. Consistent with FAA regulations, unless there is evidence to the contrary, an aircraft maintenance record produced by your maintenance recordkeeping system should be acceptable by itself, without other historic a l or source records. The important consideration here is that you have a sound and properly working recordkeeping system. You may wish to archive certain source documentation records that you used to introduce parts or components into your maintenance system. These records may include documents such as the manufacturer’s invoice for new parts, export certificates of airworthiness, documentation of a major repair or alteration, or other similar information that may be useful in the future. You may also have business reasons to maintain historical records, but you can keep historical records of your own choice, not because there are regulatory Par 8-10 Page 34

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requirements that require you to keep various historical records. The only records that we can legally require to you to make, retain, and produce for our review are those records that we have clearly outlined in 14 CFR.

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**CHAPTER 9. CONTRACT MAINTENANCE**

9-1. CONTRACT MAINTENANCE. In the past, many nonregulatory words and terms have been used in the aviation industry to describe a person who performs maintenance, preventive maintenance, and alterations for an air carrier, such as outsource, contract, emergency, vendor, oncall, and maintenance, repair, and overhaul (MRO) facilities. The term contract maintenance means any maintenance, preventive maintenance, or alterations accomplished by a certificate holder’s mainte nance provider. However, the certificate holder always retains primary responsibility for any contract maintenance accomplished by a maintenance provider.

a. Maintenance Provider (MP). Title 14 CFR part 121, § 121.368(a)(1) and part 135, § 135.426(a)(1) define a maintenance provider as any person who performs maintenance, preventive maintenance, or an alteration for a certificate holder other than a person who is trained by and employed directly by that certificate holder.

b. Covered Work. Sections 121.368(a)(2) and 135.426(a)(2) define covered work as any of the following:

(1) Essential maintenance that could result in a failure, malfunction, or defect endangering the safe operation of an aircraft if not performed properly or if improper parts or materials are used;

(2) Regularly schedule maintenance; or

(3) A required inspection item on an aircraft.

NOTE: Essential maintenance is for the Required Inspection Item (RII) of on-wing maintenance. “On-wing maintenance” is to mean the entire aircraft.

In addition, covered work includes both essential maintenance and RIIs, both of which include nonscheduled maintenance. Additionally, other requirements that address both covered work and all other contract maintenance, such as the requirements for air carriers to develop policies, procedures, methods, and instructions for accomplishing all contracted maintenance, necessarily include both scheduled and nonscheduled work.

c. Directly in Charge. Sections 121.368(a)(3) and 135.426(a)(3) define directly in charge as having responsibility for covered work performed by a maintenance provider. A representative of the certificate holder directly in charge of covered work does not need to physically observe and direct each maintenance provider constantly, but must be available for consultatio n on matters requiring instructio n or decision.

NOTE: The term available for consultation may be broadly interpreted.

This allows the air carrier flexibility to use numerous information technology me thods – such as high resolution photographs, text messaging, and the Internet – to acquire the information necessary to make decisions and provide instructions.

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d. Contract Maintenance Requirements. Sections 121.368 and 135.426 require:

(1) Each certificate holder must be directly in charge of all covered work done for it by a maintenance provider.

(2) Each maintenance provider must perform all covered work in accordance with the certificate holder’s maintenance manual.

(3) No maintenance provider may perform covered work unless that work is carried out under the supervision and control of the certificate holder.

(4) Each certificate holder who contracts for maintenance, preventive maintenance, or alterations must develop and implement policies, procedures, methods, and instructions for the accomplishment of all contracted maintenance, preventive maintenance, and alterations. These policies, procedures, methods, and instructions must provide for the maintenance, preventive maintenance, and alterations to be performed in accordance with the certificate holder’s maintenance program and maintenance manual.

(5) Each certificate holder who contracts for maintenance, preventive maintenance, or alterations must ensure that its system for the continuing analysis and surveillance of the mainte nance, preventive maintenance, and alterations carried out by the maintenance provider, as required by §§ 121.373(a) and 135.431(a), contains procedures for oversight of all contracted work.

(6) The policies, procedures, methods, and instructions required by paragraphs 9-1d(4) and 9-1d(5) must be acceptable to the FAA and included in the certificate holder’s maintenance manual, as required by §§ 121.369(b)(10) and 135.427(b)(10).

(7) Each certificate holder who contracts for maintenance, preventive maintenance, or alterations must provide to its FAA certificate-ho ld i ng district office (CHDO) a list of maintenance providers in a format acceptable to the FAA. This list must include the name and physical (street) address, or addresses, where each maintenance provider performs work for the certificate holder, and a description of the type of maintenance, preventive maintenance, or alteration that is to be performed at each location. The list must be updated with any changes, including additions or deletions, and the updated list provided to the FAA in a format acceptable to the FAA by the last day of each calendar month.

(a) When submitting the maintenance provider list (MPL) required by §§ 121.368(h) and 135.426(h) to the FAA, there are two MPL templates available to air carriers which are acceptable to the FAA: MPL Template-Excel and MPL Template-XML. Both templates can be downloaded from the Flight Standards Service Aircraft Maintenance Divis io n (AFS-300) Web site under the AFS-300 Job Aids section. Two additional MPL informational files are available on the Web site:

1. MPL Import – This document defines field names, descriptions, field length, and other informatio n required to understand the required structure of both of the supported formats.

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2. MPL Informat io n – This document provides informatio n and instructio ns about contractors used by 14 CFR parts 121, 135, 121/135, and 145 in two formats; these formats are Excel and XML.

(b) Once completed, the MPL must be submitted to the air carrier’s FAA CHDO by the last day of each calendar month. The AFS-300 Web site can be found at http://www.faa.gov/about/office_org/headquarters_offices/avs/offices/afs/afs300/.

NOTE: The MPL does not include subcontractors used by the MP. The air carrie r should accept the MP’s subcontractors at the forefront of the contractual agreement and ensure that procedures exist to notify the air carrie r of any future changes.

9-2. RESPONSIBILITY FOR MAINTENANCE PERFORMED BY OTHERS. Consistent with part 121, § 121.1(b), part 135, § 135.1(a)(2), and others, when you use an MP to accomplis h all or part of the maintenance activities on your airplane or its component parts, that MP becomes part of your maintenance organization and falls under your control. Additionally, §§ 121.363 and 135.413 make it clear that you remain primarily responsible for all of the maintenance performed by that MP on your aircraft. You must determine that the MP has the capability to do your work on your behalf, direct their work, and determine that their work was done satisfactorily according to your manual and your standards. Because all work on your aircraft must be performed in accordance with your maintenance manual and your maintenance program, you must also provide the MP with appropriate materia l from your mainte na nce manual for that work. You must ensure that the MP follows the procedures in your manual that you have provided (see subparagraph 3-2c). You should accomplish this through work-in-progress audits while the MP is actually accomplishing the work. Your manual system should accommodate work performed for you by each MP. The policy and procedures portion of your maintenance manual should assign clear authority and responsibilities and outline procedures for your personnel to administer, control, and direct all contract maintenance. You should arrange the technical material that you provide for the use and guidance of the MP. You should have a written contract with anyone performing contract maintenance for you on a continuing basis. This will help ensure that your responsibilities are addressed. In the case of major operations, such as engine, propeller, or airframe overhaul, the contract should include a specification for the work. You should include or reference that specification in your manual system.

9-3. UNSCHEDULED CONTRACT MAINTENANCE PERFORMED AWAY FROM REGULAR FACILITIES. Sometimes, you will need maintena nce performed on your aircraft while it is away from your regular maintenance facilities. You also may need maintenance services on short notice. Your maintenance manual should include procedures for obtaining these services under these unanticipated conditions. You should never use the term “emergency maintenance” to describe short notice, unscheduled maintenance, as such terms imply to your employees and your MPs that the FAA’s regulatio ns and your procedures do not have to be followed. “Emergency” means that a serious situation has occurred unexpectedly, involves a peril to life or property, and demands immediate action. An out-of-commission aircraft parked on an airport ramp could hardly constitute a peril to life or property. You should outline the procedural steps that you will take to control and direct the unscheduled maintenance Par 9-1 Page 39

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accomplished by your MP. Unscheduled, short notice requirements for maintenance do not void your responsibility to determine that your MP has the organizatio n, adequate facilities and equipment, competent personnel, and appropriate portions of your manual for the work that needs to be done. These determina t io ns must be made before any MP starts to work on your aircraft. These procedures and method of determination should be in your manual.

9-4. AIRWORTHINESS RELEASE OR AIRCRAFT LOG ENTRY REQUIRED BY §§ 121.709 AND 135.443. For the purposes of contract maintenance, it is important to note that §§ 121.709(b)(3) and 135.443(b)(3) outline specific requirements for the persons authorized to sign an airworthiness release or aircraft log entry. As defined in part 1, § 1.1, a person is an individual, firm, partnership, corporation, company, association, joint stock association, or government entity. Thus, a repair station, as a company, qualifies as a person defined in § 1.1 and can prepare, or cause to be prepared, an airworthiness release or an appropriate entry in the aircraft log. Such a release or aircraft log entry is limited to the work the repair station is rated to perform and actually performs on an aircraft for certificate holders operating under 14 CFR parts 121, 125, and 135. However, in preparing the airworthiness release or aircraft log entry, the person or, in this instance, the part 145 certificated repair station (CRS), must comply with the procedures set forth in the part 121 or 135 certificate holder’s manual for preparing the airworthiness release or aircraft log entry. Because there is no reference to “person” in §§ 121.709(b) or 135.443(b), the “certificate holder” refers not to the repair station, but the part 121 or 135 certificate holder for whom the repair station is performing maintenance. This provision corresponds to the part 121 and 135 certificate holder’s duty under §§ 121.367 and 135.425 to ensure that not only are competent personnel performing maintenance on their fleets, but that each aircraft released to service is airworthy.

a. Log Entry or Airworthiness Release Form. You must designate each individ ual authorized to execute the log entry or Airworthiness Release Form for you by name and occupationa l title. The individ ua l making the log entry or Airworthiness Release Form acts as your authorized agent. He or she certifies that the maintenance was accomplished according to your maintenance manual and maintenance program procedures, and that no known condition exists that would make the aircraft unairworthy. This arrangement does not reduce the responsibility of maintenance personnel to accomplish maintenance functio ns or tasks in accordance with your manual.

b. Proce dure s for Log Entry or Airworthine ss Re le ase Form. Consistent with §§ 121.709(b)(1) and 135.443(b)(1), you must include in your maintenance manual the procedures for making an aircraft Airworthiness Release Form or log entry. Our regulatio ns require you to make a log entry or complete an Airworthiness Release Form before you can operate your aircraft for any reason after you have accomplished any maintenance. You are required to make a log entry or an Airworthiness Release Form. Other than form or format, there is no legal or technical difference between an Airworthiness Release Form and a log entry.

9-5. EVALUATING NEW MAINTENANCE PROVIDERS. Before you can use an MP for the first time, you must determine that the MP candidate complies with pertinent requirements of part 121 subpart L or part 135 subpart J. In most cases, you would conduct an onsite audit. You must demonstrate, through this audit or by some other means, that the MP has an adequate organization, adequate facilities and equipment, competent personnel, and is capable of Par 9-3 Page 40

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performing the work consistent with the requirements of your program. You should use a risk assessment process to determine whether to accomplish an onsite audit or not. Your risk assessment should take into account what happens (the failure effect) when the aircraft part or aircraft system that the MP works on fails. If the failure effect is safety, your procedures should mandate an initial onsite audit along with recurrent onsite audits, as well as the posting of a resident employee at the MP’s facilit y, who is assigned audit and oversight duties.

NOTE: Since the failure effect of parts and systems that come under essential maintenance concerns safety, the air carrie r shouldhave robust policies and procedures to qualify, supervise, and control these MPs, which should include onsite audits.

9-6. CONTINUING MAINTENANCE PROVIDER OVERSIGHT. Ensuring that each one of your MPs is in continuo us compliance is a major functio n of your CASS. You should use your risk-based process for establishing a schedule for auditing and inspecting each of your MPs.

Inherent with a risk-based process, you may determine that some of your MPs do not require an onsite audit. Consistent with the “performance” wording of § 121.373 or § 135.431, the audits that you accomplish should be primarily work-in-progress audits that serve to determine that your MPs are followin g your manual. The audits should be accomplished by trained auditors, and the results analyzed by trained analysts. The results of the analysis should permit you to determine each MP’s continuing compliance with part 121 subpart L or part 135 subpart J, as appropriate, and your maintenance program.

**9-7. USING A CERTIFICATED REPAIR STATION (CRS) AS ONE OF YOUR MAINTENANCE PROVIDERS.**

a. Arrangements for Maintenance. If you decide to exercise your authority under § 121.379 or § 135.437 to make arrangements with other persons to accomplish contract maintenance for you as provided in your manual, you may choose to make these arrangements with an FAA CRS, but these rules do not require you to do so. The scope of your authorization to make arrangements for maintenance is very broad; you can make arrangements for maintenance with any person as that term is defined in 14 CFR part 1, § 1.1, as long as that MP accomplishes your maintenance in accordance with your manual and maintenance program. Although the § 1.1 term “person” include s a CRS, it also includes anyone who does not hold an FAA certification.

b. Part 145 MP. The air carrier regulatory and maintenance program requirements that you would use to qualify an MP that holds a current part 145 repair station certificate are exactly the same as those that you would use for an MP who does not hold a current part 145 repair station certificate; there is no difference. Consistent with § 119.1(c), § 121.1(b), or § 135.1(a)(2), each person, whether certificated or not, that is employed or used by you for any maintenance, preventive maintenance, or alteration of your aircraft is required to comply with the part 121 requirements and your maintenance program requirements, not 14 CFR part 65 or 145 requireme nt s (see paragraph 8-3). Further, your § 121.379(b) or § 135.437(b) authorization to approve your aircraft for return to service after maintenance extends to the work accomplished under your § 121.379(a) or § 135.437(a) authorization to make arrangements with other persons for maintenance.

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**CHAPTER 10. PERSONNEL TRAINING**

10-1. MAINTENANCE PROGRAM TRAINING REQUIREMENTS. You can find your specific air carrier maintenance training requirements in certain sections of 14 CFR part 121 subpart L and part 135 subpart J. Part 121, § 121.375 and part 135, § 135.433 require you to have a training program that ensures each person (including inspection personnel) who determines the adequacy of work done for you is fully informed about procedures, techniques, and new equipment in use, and is competent to perform his or her duties. There is an additional implied training requirement in part 121 subpart L and part 135 subpart J based on your responsibility to provide competent personnel for the proper performance of your maintenance program. A training program is the logical means for ensuring that maintenance personnel are competent.

FAA regulatio ns allow you to develop a training program that fits your particular needs.

10-2. TYPES OF TRAINING. Some of the possible types of training in your training program are initial training, recurrent training, specialized training, competency-based training, and maintenance provider (MP) training. You should select the appropriate training for your personnel, includ ing your MP personnel, which you should base on an assessment of training needs. This assessment is a reflection of the required knowledge, skills, and ability to properly accomplish a given task or function, and the current capability of those who you would assign a particular task or function.

10-3. INITIAL TRAINING. You should provide initial training right after you hire an employee, or when your existing employees begin to work on new equipment or a new assignment. Your initial training program may include subjects such as employee indoctrination or orientat io n; maintenance department policies and procedures; maintenance recordkeeping and documentation; aircraft systems or ground equipment; specific skills (e.g., avionics, composite repair, aircraft run-up and taxi); skills upgrade; human factors; task-specific training;

hazardous materials (hazmat); or Enviro nmental Protection Agency (EPA) and Occupational Safety and Health Administ rat io n (OSHA) regulat io ns familia r iza t io n. Your init ia l training should also include a competence-based assessment of employees. This evaluates an employee’s previous training and experience and helps identify his or her specific individ ual training needs.

The objective is to provide training that addresses the gap between required competence and the competence an individual already has.

10-4. RECURRENT TRAINING. Recurrent training is education occurring on a repetitive basis. You must provide maintenance personnel with the informatio n and skills necessary to maintain your standard of competence. This training also accommodates the introduction of new aircraft; aircraft modifications; new or different ground equipment; new procedures, techniques, and methods; or other new informatio n. Your recurrent training, although occurring on a repetitive basis, may not adhere to a defined schedule. You should not provide repetitive informatio n in recurrent training unless it is needed to maintain the desired degree of competence. Your recurrent training may include:

• Continuing competency training designed to maintain regulatory and certificate currency requirements.

• Refresher training on a seldom-accomplished task or seldom-used skill.

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• Update training for particular tasks or skills. Update training can include training bullet ins, bullet in board items, self-study tasks, and computer-based instruction (CBI).

• Any other continuing education or training that may not be provided on a defined schedule.

10-5. SPECIALIZED TRAINING. Your specialized training should focus on competence in specific tasks or Areas of Responsibility (AOR), such as Required Inspection Items (RII), borescope, nondestructive testing, or flight control rigging. You might provide this training with initial or recurrent training. You do not need to limit it to maintenance subjects, but instead may include management skills training for new supervisors, computer skills, or other training necessary because of a change in an individual’s duties and responsibilities.

10-6. M AINTENANCE PROVIDER TRAINING. Your training program must provide appropriate information to each employee of a MP about your specific program. The training should include functio n-specific training appropriate to each person’s job assignment or AOR.

You do not need to provide training to MP personnel in areas that do not concern them. For example, training on aircraft log procedures and minimum equipment list (MEL) procedures would not be required for aircraft interior cleaners, but would be required for maintenance personnel assigned to oncall maintenance for you.

NOTE: If your MP has specific types of training for its personnel, you do not need to duplicate that training for those individuals. However, you must ensure your MP actually has provided the training, and that the training meets your own needs and training standards. This could be a Continuing Analysis and Surveillance System (CASS) work-in-prog re ss audit.

10-7. COMPETENCY-BASED TRAINING. Although air carriers historically have provided a specified number of maintenance training hours to ensure employees have the competencies needed for their jobs, studies have shown that it may be better for you to train to a competency-based standard. You do not have to perform this type of training on a defined schedule or for a specific number of hours. Rather, you should test each individ ual to evaluate what training he or she needs, and then use these evaluatio ns to identify those personnel who retain a high level of subject competence and who may not require a particular block of instructio n. Conversely, you also should identify those individ uals who require more training.

Training to competence permits you to tailor training programs to the specific requirements of your individ ual maintenance personnel and MPs.

a. When to Require Competency-Based Training. You could use competency-based training to raise an employee’s level of competence to that level required by the individual’s duties and responsibilities. You should have procedures to determine when an individual requires competency-based training. You may determine the nee d for this type of training through pre- or post-employment testing, or through the analysis and corrective action functio ns of your CASS.

If you use competency-based training, it should specifically address the lack of competence. In some instances, competency-based training may consist of an appropriately knowledgeable person simply reviewing procedures with an employee through on-the-job training (OJT). You should design competency-based training to fix an immed iate knowledge or skill deficie nc y, and Par 10-4 Page 44

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the training may focus on one individ ual or a small group. You may include competency-based training in your initial or recurrent training requireme nts.

b. Com petency Deficiencies. For those circumstances where you identify a competency deficiency through the investigatio n of an event, your competency-based training should show an individual what happened, why it happened and demonstrate, in a positive manner how to prevent it from happening again.

c. Competency Improvement Training. You should orient your competency improvement training toward correcting personnel competence deficiencies that you have identified through your CASS.

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**CHAPTER 11. CONTINUING ANALYSIS AND SURVEILLANCE S YSTEM**

11-1. BACKGROUND OF THE CONTINUING ANALYSIS AND SURVEILLANCE SYSTEM (CASS). Introductio n of the CASS requirement resulted from an FAA industry study of a series of maintenance-rel ated air carrier accidents occurring during the 1950s. The study found that, in many cases, the primary causal factor of an accident was a fundamental weakness or weaknesses in the air carrier maintenance program. The study found that in some cases maintenance personnel failed to accomplish required maintenance tasks or failed to accomplish the task correctly. They simply didn’t follow the manual. In other cases, the study found that the maintenance program, even when followed as planned and documented, was not effective in preventing the situation that led to the accident. It did not produce the desired results.

a. Regulations. Responding to this finding, we introduced regulations (14 CFR part 121, § 121.373 and part 135, § 135.431) that require you to establish and maintain a system for the CASS of the performance and effectiveness of your maintenance program.

b. Correcting Deficiencies. These regulatio ns further require that you include a process in your CASS to correct any deficiency identified in your maintenance program, regardless of whether you did the work or had a maintenance provider (MP) do the work.

11-2. CASS IS A SAFETY MANAGEMENT TOOL. A CASS is your system for managing safety as it relates to maintenance functions. As a tool to manage safety, it is part of your overall structure of policies and procedures that you use to ensure your operations are to the highest possible degree of safety. It is a structured, methodical process that helps you reach your maintenance program objectives. CASS is the only management system that we currently mandate by regulatio n. If you use it properly, your CASS becomes an inherent way of doing business for you, and helps you to promote a culture of safety in your company by providing a formal process for your employees to identify and correct safety deficiencies. As you will see in the following brief discussion of the structure of a CASS, the same objectives of measuring and continuo usly improving the performance (program executio n) and effectiveness (program results) of a major functio n (maintenance) apply equally to all safety-related maintenance program functio ns that you must manage.

**11-3. BASIC CASS PROCESSES.**

a. CASS Processes. Your CASS is a risk-based, closed-loop system that has four basic processes:

(1) Surveillance. An informatio n gathering/audit process you use to collect data to measure your program execution and measure your program results.

(2) Analysis. An analysis process you use to identify any maintenance program deficiencies and any necessary corrective actions.

(3) Corre ctive Action. A planning process you use to ensure that your corrective actions are imple me nted.

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(4) Followup. A performance measurement process that you use to verify that your corrective actions are effective. This is also an information gathering and analysis process, thereby closing the loop.

b. Using an Audit Program.

(1) During the first step, surveillance, you will gather and obtain data using an audit program to support measurement of performance (program execution). Your audit program should be well-structured, based on risk assessment, and accomplished by individuals trained and skilled specifically at auditing. Consistent with the wording of the regulatio n, your primary type of audit should be work-in-progress audits that evaluate if the worker is following the manual.

Your auditors would also look at areas, such as manuals and other maintenance technical data, aircraft condition, actual in-process maintenance practices, training, publicatio ns, and ground operations.

(2) In addition, information gathering to obtain data that will support the measurement of effectiveness (program results) is generally a collection of flight operational data, such as accidents/incidents, mechanical delays and cancellations, in-flight engine shutdowns, unscheduled landings, engine performance, pilot logbook writeups, and unconfirmed component or part removals.

c. Data Analysis. In the second step, you will analyze the data to identify indications of maintenance program weaknesses. Your data analysis should be accomplished by individuals experienced and/or trained as analysts. One of your key objectives here is to not only identify a weakness, but to determine its root cause. This is where your knowledge of human factors becomes critical.

d. Developing Corrective Action. Based on the results of your analysis, the third step is for you to develop a corrective action, if necessary, again taking into account human factors so that your corrective action is likely to be successful. Once you determine what the corrective action is, you will develop and implement a corrective action plan (CAP).

e. Conduct a Followup Measurement Process. To close the loop, the fourth step of your CASS will have you conduct a followup measurement process using surveillance and analys is to verify that your corrective action has effectively corrected the deficiency that you identified. You can design this followup data-gathering process specifically for the issue of interest, or you can make it a part of your continuing surveillance that is the first step of your CASS. Determining if you need a special informatio n gathering procedure is part of your analysis that you accomplished in step three.

f. Aspects of Surveillance. Note that both the initial and followup surveillance can and should have proactive and reactive aspects to them. In the case of audits by auditing systems and procedures, as well as specific transactions, the analysis of audit results can identify weaknesses in a process. Correcting these weaknesses before a problem results is a proactive approach. An audit also may uncover a missed or improper maintenance action. Investigating this finding and correcting the immediate problem is a reactive process. Developing and implementing a corrective action to prevent a similar future event is equally important for improving the Par 11-3 Page 48

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maintenance program, and the regulatio ns require it. Similarly, your analysis of operational performance data from a systems point of view can result in identification of a system’s weakness before a specific unwanted event (e.g., a cancellation) occurs, which is a proactive process. Investigating and correcting an undesirable operational event related to the maintenance program after it has occurred, though reactive, is also a necessary and desirable procedure.

11-4. RISK-BASED DECISIONS. All effective CASSs take into account the need to manage risk to an acceptable level, as well as the practical limitations that you must face when addressing deficiencies. Consequently, you must set priorities and make choices for planning audits and other information gathering activities, analyzing data, and selecting and implementing corrective actions. You should tie setting such priorities directly to a risk assessment process so that the resulting maintenance program achieves its objectives.

11-5. SCOPE OF A CASS. The CASS monitors all 10 elements of your maintenance program:

• Airworthiness responsibility,

• Air carrier maintenance manual,

• Air carrier maintenance organizatio n,

• Accomplishment and approval of maintenance and alterations,

• Maintenance schedule,

• Required Inspection Items (RII),

• Maintenance recordkeeping system,

• Contract maintenance,

• Personnel training, and

• CASS.

**11-6. CASS DESIGN PRINCIPLES.**

a. Attributes of System Safety.

(1) Clear authority.

(2) Clear responsibility.

(3) Specific written procedures.

(4) Effective controls.

(5) Performance measures.

(6) Well-defined interfaces.

b. CASS Design. These six system safety attributes should be the starting point for the design of your CASS. It should be clear who in your organizatio n is responsible for, and who has authority over, the CASS. You should not divide responsibility/authority into two or more parts due to the likely possibility that activity such as auditing and operations data analysis are poorly coordinated. Typically, in addition to an individual with overall CASS responsibility, you should Par 11-3 Page 49

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have a management board or committee to ensure good communication and coordination of all CASS functio ns, and to maintain regular senior level management involvement. This oversight group also can provide a form of control over critical aspects of your CASS operation and measure the performance and effectiveness of the CASS itself.

c. CASS Interfaces. In addition to the many elements within your maintenance organization, there are many interfaces between the CASS and functions or organizational elements of a typical air carrier that are outside maintenance. Some of the more obvious examples are engineering, flight operations, purchasing, safety, and the FAA. It also is important that you clearly define and coordinate your CASS relationships to your other programs (if they exist), such as Internal Evaluatio n Programs (IEP), flight operations quality assurance (FOQA) programs, voluntary disclosures, and Aviatio n Safety Action Programs (ASAP).

**11-7. CASS PERSONNEL REQUIREMENTS.**

a. Effective CASS Skills. An effective CASS requires certain skills that you may not have readily availab le within your maintenance organizatio n. For example, auditing skills are not automatica l ly inherent in those skilled in accomplis hing mainte na nce. Analys is capabilit y, particularly related to root cause determination, risk analysis, and consideration of human factors, is specialized and generally requires sp ecific training and experience.

b. Sharing Personnel. For all operators, but particularly for the smaller ones, required CASS personnel can be shared. You may choose to have your personnel perform CASS functions as a collateral duty, and you may choose to hire someone outside your organizatio n to accomplish some or all of your CASS functions. However, it is essential that you recognize the need for knowledge and skills in your CASS that do not necessarily coincide with those knowledge and skills resulting from many years of maintenance experience repairing airplanes.

NOTE: You can find more detailed information concerning developing and implementing a CASS in AC 120-79.

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**CHAPTER 12. ADMINISTRATIVE**

12-1. WHOM TO CONTACT. If you have questions about the material in this AC or would like to provide feedback, you may use the following communication links. By mail: Manager, Air Carrier Maintenance Branch, AFS-330, Federal Aviation Administration Headquarters, 5th Floor, 950 L’Enfant Plaza, S.W., Washington, DC 20024. By phone at: 202-267-1685.

12-2. REGULATORY REFERENCES. You can find the regulatio ns that underlie this AC in 14 CFR. A summary of specific regulatio ns :

• Scope of Regulatory Applicability, §§ 119.1(c), 121.1(b), and 135.1(a)(2).

• Air Carriers’ Responsibility for Airworthiness and Performing Maintenance,

§§ 121.363 and 135.413.

• Air Carrier Maintenance Programs, § 119.5, 119.49, 121.133, 121.367, or 135.21.

• Air Carrier Maintenance Program Manual, §§ 121.133, 121.137, 121.367, 121.369,

135.21, and 135.427.

• Air Carrier Maintenance Organization, §§ 119.65, 119.67, 119.69, 119.71, 121.365, and

135.423.

• Air Carrier Maintenance Time Limitations, §§ 119.49, 121.135, and 135.23.

Performance and Approval of Maintenance and Alterations, §§ 43.3(f), 43.7(e), 91.403,

91.407, 91.413, 119.1(c), 121.1(b), 121.379, 135.1(a)(2), and 135.437.

• Performance and Approval of Maintenance and Alterations Performed by Other Persons, §§ 119.1(c), 121.1(b), 121.368, 121.379, 135.1(a)(2), 135.426, and 135.437.

• Air Carrier Continuing Analysis and Surveillance System (CASS), §§ 121.373 and

135.431.

• Air Carrier Personnel Training, §§ 121.367(c), 121.375, and 135.433.

• Air Carrier Maintenance Recordkeeping and Reports, Part 121 Subpart V; and §§ 43.9(b), 121.369(c), 121.380, 135.415, 135.417, 135.427, and 135.439(b).

• Maintenance Log, §§ 121.563, 121.701, 121.709, and 135.65.

• Service Difficulty Reports (SDR), §§ 121.703 and 135.415.

• Required Inspection Items (RII), §§ 121.365, 121.369, 121.371, 135.427, and 135.429.

• Mechanical Interruption Reports, §§ 121.705 and 135.417.

• Alteration and Repair Reports, §§ 43.9(b), 121.707, and 135.439(a)(2)(vi).

12-3. OTHER RELATED REGULATIONS AND GUIDANCE MATERIAL. For more informatio n, consult these current editions:

• Title 14 CFR Parts 1, 3, 26, 43, 91, 119, 121, and 135.

• Title 49 U.S.C. § 46310, Reporting and Recordkeeping Violations.

• AC 120-59, Air Carrier Internal Evaluatio n Programs.

• AC 120-73, Damage Tolerance Assessment of Repairs to Pressurized Fuselages.

• AC 120-77, Maintenance and Alteration Data.

• AC 120-78, Acceptance and Use of Electronic Signatures, Electronic Recordkeeping Systems, and Electronic Manuals.

• AC 120-79, Developing and Implementing an Air Carrier Continuing Analysis and Surveillance System.

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• FAA Order 8110.103, Alternative Methods of Compliance (AMOC).

• FAA Order 8620.2, Applicability and Enforcement of Manufacturer’s Data.

• FAA Order 8900.1, Flight Standards Information Management System (FSIMS).

• Air Transport Association (ATA) Maintenance Steering Group—3rd Task Force (MSG–3), Operator/Manufacturer Scheduled Maintenance Development.

• Report Number AD-A066-579, Reliability-Centered Maintenance.

12-4. OBTAINING REFERENCE MATERIAL (current editions):

• You can find this AC at http://www.faa.gov/regulations_policies/advisory_circula rs/.

Operators can find this AC and FAA Order 8900.1, Flight Standards Information Management System (FSIMS), at http://fsims.faa.gov. The public can find this AC and FAA Order 8620.2, Applicability and Enforcement of Manufacturer’s Data, at http://www.faa.g ov/regulation s_poli cies/orders_n oti ces/.

• You can request MSG-3 infor mat io n from the Airlines for America (A4A), 1301 Pennsylvania Ave., NW, Suite 1100, Washington, D.C. 20004. You can also contact A4A at https://publications.airlines.org/.

• You can get Report Number AD-A066-579, Reliability-Centered Maintenance, from the U.S. Department of Commerce (DOC), National Technical Information Service (NTIS), 5301 Shawnee Road, Alexandria, VA 22312. You can reach their Sales Desk at 1-800-553- 6847 or 703-605-6000, 8 a.m.—6 p.m. Eastern Standard Time (EST), Monday—Friday. You can also access NTIS infor mat io n online at http://www.ntis.gov/.

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______________________________________________________________________ ______________________________________________________________________

______________________________________________________________________ ______________________________________________________________________

______________________________________________________________________ ______________________________________________________________________

Advisory Circular Feedback Form If you find an error in this AC, have recommendations for improving it, or have suggestions for new items/subjects to be added, you may let us know by emailing the Aircraft Maintenance Division (AFS-300) at 9-AWA-AFS-300-Division-Directives@faa.gov or contacting the Flight Standards Directives Management Officer.

Subject: AC 120-16G, Air Carrier Maintenance Programs Date: _____________________ Please check all appropriate line items:

An error (procedural or typographical) has been noted in paragraph ____________ on page _______.

Recommend paragraph _____________ on page __________ be changed as follows:

In a future change to this AC, please cover the following subject:

(Briefly describe what you want added.)

Other comments:

I would like to discuss the above. Please contact me.

Submitted by: Date: ______________________ ✔ ✔ ✔ ✔ ✔

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