Par 700 Page 23 (and 24) CHAPTER 7. REQUIRED INSPECTION ITEMS
700. REQUIRED INSPECTION ITEMS.
a. Sections 121.369(b) and 135.427(b) require you to designate certain tasks as Required Inspection Items (RII). Your RIIs cover at least those maintenance tasks that, if not properly performed or if done with improper parts or materials, could result in a failure, malfunction, or defect that would endanger the continued safe flight and landing of your aircraft. In case maintenance tasks are performed for you by other persons, you may authorize them to accomplish your RII requirement. However, you must document the arrangement and control it through your maintenance manual. Consistent with the regulations, you remain primarily responsible for the performance of each RII accomplished by the other person.
b. RIIs relate directly to flight safety. Consider all your RIIs with the same safety of flight consideration and emphasis even if accomplishing an individual RII adversely impacts your flight schedule, or is related to a scheduled or an unscheduled task or arises at an awkward time or at an inconvenient location.
701. RII PROCEDURES, STANDARDS, AND LIMITS.
a. Your manual must include procedures for you to identify and authorize RII personnel, both within your organization and within other organizations that perform maintenance on your behalf (§§ 121.369(b)(3) and 135.427(b)(3)). Each individual that you grant an RII authorization to must hold an appropriate airman’s certificate. This is an air carrier qualification requirement;
the individual certificate is not exercised when accomplishing the RII. You must formally notify each of these individuals of their RII authorization as well as its scope (§§ 121.371(d) and
135.429(e)).
b. You should clearly identify your RII requirements on work forms, job cards, engineering orders, and the like, or by any other method consistent with your maintenance program. A primary concept of the RII function is that the person performing the item of work may not perform the required inspection on that item of work. Therefore, it is important that you identify RIIs whenever possible so that everyone knows that an RII is required.
c. You must 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 required inspection items. As you will not find required inspection items or procedures, standards, and limits for required inspection items in an OEM manual, you will have to develop these and put them in your manual.
d. You must have procedures in your manual to ensure that only a supervisor of an inspection unit or the person who has overall responsibility for both the RII function and other maintenance and alteration functions may countermand the decision of any RII inspector regarding an RII (§§ 121.369(b)(8) and 135.427(b)(8)). These requirements apply equally to an organization performing maintenance on your behalf, as well as your own maintenance organization. See Figure 4-1 for a representative organizational chart.
Par 800 Page 25 CHAPTER 8. MAINTENANCE RECORDKEEPING SYSTEM
800. 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 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 information supports identification of the current inspection and airworthiness status of your aircraft.
801. PART 43 REQUIREMENTS. You can find the basic requirement to make a maintenance record in § 43.9(a); however, § 43.9(b) indicates that the governing requirements for you, an air carrier, are found in part 121 or part 135. That is another way of saying that the recordkeeping requirements of part 43(a) do not apply to you. However, the requirements of § 43.9(b) are consistent with the air carrier maintenance recordkeeping requirements of §§ 121.369(c) and
121.380(a) and (c), or §§ 135.427(c) and 135.439.
802. WORK PERFORMED BY A PART 145 REPAIR STATION.
a. Section 145.219 sets forth requirements for a certificated repair station 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 accomplishing any work on your aircraft.
b. The wording of the § 145.205, regulations as well as §§ 119.1(c), 121.1(b) and
135.1(a)(2) compel a part 145 certificated repair station 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 certificated repair station must use the performance standards of part 121 or part 135, including the recordkeeping requirements, instead of following the provisions in part 145 and the repair station’s repair station manual. 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, the FAA’s regulations do not preclude them from doing so. Asking the part 145 repair station to keep your records for you is consistent with regulations, although you are responsible for retaining them and making them available to the FAA. This is consistent with the requirements of § 119.59(c).
Page 26 Par 803
803. PENALTIES FOR IMPROPER AIR CARRIER MAINTENANCE RECORDKEEPING.
a. Maintenance records are important for:
(1) You as operator to fulfill your responsibility to determine the airworthiness status of your aircraft.
(2) The FAA to use them for its continuing review of aircraft maintenance records as a direct means of determining the airworthiness and safety status of air carrier aircraft.
b. 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 imposition of substantial fines and/or imprisonment.
804. MAKING AND KEEPING REQUIRED RECORDS.
a. FAA regulations (§ 121.369(c) or § 135.427(c)) require you to have and use a recordkeeping system for the preparation, storage, and retention of required aircraft maintenance records. 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 your aircraft is airworthy and capable of safe flight.
b. FAA regulations (§ 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.
805. REQUIRED AIR CARRIER MAINTENANCE RECORDS. Current requirements found in §§ 121.380 and 135.439 call for two types of records: a list of summary information and air carrier Airworthiness Release Form records.
806. WHEN TO MAKE RECORDS AVAILABLE TO THE FAA. Section 119.59(c) mandates you must make your air carrier maintenance records available to the FAA. The FAA can require you to make your records available to them at any time.
807. 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.
Par 808 Page 27
808. REQUIRED RECORDS. You are required to make and keep certain summary status records. Summary current status recordkeeping requirements are listed in §§ 121.380 and
135.427 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.
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 (hours, cycles, calendar time);
(2) The time in service remaining to the specified life limit expressed in the appropriate parameter (hours, cycles, calendar time);
(3) The specified life limit expressed in the appropriate parameter (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, and
(4) The time in service when the next scheduled overhaul is due.
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 return to service.
Page 28 Par 808
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 maintained;
(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 maintained;
(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 maintained is due.
e. Current Status of Applicable Airworthiness Directives (AD). The current status of applicable ADs means a record that contains at least the following information:
(1) Identification of the particular airframe, engine, propeller, appliance, or component to which the AD is applicable.
(2) The AD number (and/or regulatory amendment number).
(3) The date when the required action was accomplished and the time in service expressed in the appropriate parameter (hours, cycles, calendar time).
(4) If the requirement is recurring, the date when the next action is due, and the time in service expressed in the appropriate parameter (hours, cycles, calendar time).
(5) 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 permits the use of more than one method of compliance, the record must include a reference to the specific method of compliance used. If the operator uses an alternate method of compliance (AMOC) to comply with an AD, the method of compliance means a description of this AMOC and a copy of the FAA approval.
NOTE: The listing of current status of an AD or method of compliance must not be confused with an AD record of accomplishment, which is a description of the work and who performed it and/or issued the approval for return to service.
f. The current major alterations of each airframe, engine, propeller, and appliance. A listing means a record that contains at least the following information:
Par 808 Page 29
(1) A listing identifying each major alteration, as well as the associated item to which the major alteration has been installed, and
(2) A description of, or reference to, the FAA-approved technical data 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 return to service. You must not confuse this listing with the requirement to submit a copy of each report of a major alteration to the FAA.
g. 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 requirement 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, NOTE: An overhaul record is not required to contain a record of AD accomplishment. The regulations require separate records of AD current status. The regulations also require that the record of AD accomplishment be kept, but for only one year.
(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.
809. OTHER REQUIRED RECORDS AND REPORTS. The FAA regulations 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 elements of your maintenance program. These records are one of the sources of information for your CASS. The FAA also uses these reports in its continuous 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
Page 30 Par 809 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 Log Entry before you can operate your air carrier aircraft after any maintenance, preventive maintenance, or alterations are performed, whether the aircraft is operated 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, it must be kept separate and distinct from the aircraft log and is not included in the maintenance records. 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) An Aircraft Log Entry. If you make a Log Entry, you do not have to issue an Airworthiness Release Form. To avoid confusion and to be consistent with the regulations, you should not identify this entry in the aircraft log as an airworthiness release. 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 approval 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 certifications consistent with statutory considerations for operations with the highest degree of safety in the public interest.
(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 condition exists that would make the aircraft non-airworthy; and
Par 809 Page 31
(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 Airworthiness Release Form or Log Entry must be accomplished by an authorized mechanic or repairman on your behalf under your part 121 or part 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 Airworthiness Release Form or make a maintenance Log Entry unless they have been authorized by you.
NOTE: Because a part 145 repair station is not an individual, these same regulations preclude accomplishment of your Airworthiness Release Form or Log Entry by a part 145 certificated repair station. With one exception, the Airworthiness Release Form or Log Entry must be executed by an authorized, certificated individual as described in part 121 or part 135, and according to your procedures. The authorized individual may be employed by the repair station, but they are acting on your behalf, not on behalf of the repair station. This is consistent with §§ 119.1(c) and 121.1(b) or 135.1(a)(2).
(5) Your maintenance manual should include detailed procedures for accomplishing the Airworthiness Release Form or Log Entry after any maintenance is accomplished. The procedures should include processes designed to ensure that your aircraft are not operated after any maintenance, preventive maintenance, or alteration is accomplished unless the Airworthiness Release Form or maintenance Log Entry is completed.
(6) Your maintenance manual should include detailed procedures for qualifying and authorizing each individual who is authorized to accomplish your § 121.709 or § 135.443 Airworthiness Release Form or Log Entry. These procedures should include a positive, readily available means of documenting and transmitting the authorization to the individual, including the scope and limitations of their authorization.
c. Service Difficulty Reports. You are required to make service difficulty reports by §§ 121.703 and 135.415. While these reports can identify deficiencies within your maintenance program, these reports are the FAA’s primary means of gathering information for the FAA’s Service Difficulty Reporting Subsystem (SDR).
d. Mechanical Interruption Reports. You are required by §§ 121.705 and 135.417 to make mechanical interruption reports. These reports document the inability of your aircraft to arrive at its scheduled destination because of mechanical difficulties. This is a prime indicator of deficiencies in the effectiveness of your maintenance program. Moreover, analysis of these
Page 32 Par 810 reports is one of the FAA’s most useful means of oversight of the level of effectiveness of your maintenance program.
810. REQUIREMENTS FOR REPORTS OF MAJOR ALTERATIONS AND MAJOR REPAIRS.
a. If you are a part 121 air carrier, § 121.707 requires you to make a report of each major alteration and repair. The alteration report must be submitted to the FAA and the major repair report must be made available for inspection by the FAA. 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 repair that you accomplished.
b. If you are a part 135 air carrier, there is no requirement to submit any reports of major alterations or repairs. However, as with any required record of aircraft maintenance or alteration, you must make them available to the FAA upon request.
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.
811. 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 your procedures are being followed and are effective. This ensures your required records are true and accurate. Records such as the inservice history of life-limited parts (traceability back to birth) or the record of accomplishment of an AD do not need to be kept indefinitely. Remember, there are severe criminal penalties for falsifying, or failing to make, or keep air carrier records. Consistent with the 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 historical 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 business reasons would not relate to the absence of any FAA regulatory requirements for historical records. The only records that you are legally required to make and retain are those records that are clearly outlined in 14 CFR.
Par 900 Page 33 CHAPTER 9. CONTRACT MAINTENANCE
900. RESPONSIBILITY FOR MAINTENANCE PERFORMED BY OTHERS. Consistent with §§ 121.1(b), 135.1(b)(2) and others, when you use a maintenance provider to accomplish all or part of the maintenance activities on your airplane or its component parts, that maintenance provider becomes, in effect, part of your maintenance organization and under your control.
However, §§ 121.363 and 135.413 make it clear that you remain primarily responsible for all of the maintenance performed by that maintenance provider on your aircraft. You must determine that the maintenance provider 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 maintenance provider with appropriate material from your maintenance manual for that work. You must ensure that the maintenance provider follows the procedures in your manual that you have provided. You should accomplish this through work-in-progress audits while the maintenance provider is accomplishing the work. Your manual system should accommodate work performed for you by each maintenance provider. 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 contracted work. The technical material that you provide should be arranged for the use and guidance of the maintenance provider. When possible, you should have a written contract with anyone performing maintenance work for you on a continuing basis. This will help ensure 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.
901. UNSCHEDULED MAINTENANCE PERFORMED AWAY FROM REGULAR FACILITIES. Sometimes, you will need maintenance 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 workforce that FAA’s regulations 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 you will take to control and direct the unscheduled maintenance that is required. Unscheduled, short-notice requirements for maintenance do not void your responsibility to determine that your maintenance provider has the organization, adequate facilities and equipment, competent personnel, and appropriate portions of your manual for the work that needs to be done. These determinations must be made before any maintenance provider starts to work on your aircraft. These procedures and determinations should be in your manual.
902. AIRWORTHINESS RELEASE FORM OR AIRCRAFT LOG ENTRY.
Sections 121.379(b) and 135.437(b) authorize you to approve your aircraft, airframes, aircraft engines, propellers, or appliances for return to service after you accomplish any maintenance, preventive maintenance, and alterations. These sections only authorize any person other than you
Page 34 Par 902 to approve your aircraft for return to service. §§ 121.709(b) and 135.443(b) outline requirements for those personnel making a Log Entry or issuing an air carrier Airworthiness Release Form under part 121 or part 135. These regulations require a certificated repairman, or certificated airframe and powerplant mechanic that you authorize to make the Log Entry or issue the Airworthiness Release Form for you. These regulations clearly do not authorize a repair station certificated under part 145 or any other entity to make an Airworthiness Release Form or Log Entry on your behalf. The regulations set forth clear personnel qualification requirements for each individual you so authorize. The approval for return to service authority remains solely with you. An individual may not issue an approval for return to service for your aircraft unless you authorize them to do so.
a. You must designate each individual authorized to execute the Log Entry or Airworthiness Release Form for you by name and occupational title. The individual 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 non-airworthy. This arrangement does not reduce the responsibility of maintenance personnel to accomplish maintenance functions or tasks in accordance with your manual.
b. 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. A Log Entry or Airworthiness Release Form is required to be accomplished 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. Other than form or format, there is no legal or technical difference between an Airworthiness Release Form and a Log Entry.
903. EVALUATING NEW CONTRACT MAINTENANCE PROVIDERS. Before you can use a maintenance provider for the first time, you must determine that the maintenance provider 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 maintenance provider has an adequate organization, adequate facilities and equipment, competent personnel and is capable of performing the work consistent with the requirements of your program. Your determination of whether to accomplish an on-site audit should be based on risk assessment. The risk assessment should take into account the aircraft part failure or system loss of function, and the consequence of the loss of function related to the work being accomplished.
904. CONTINUING MAINTENANCE PROVIDER OVERSIGHT. Ensuring that each one of your maintenance providers is in continuous compliance is a major function of your CASS.
You should use your risk-based process for establishing a schedule for auditing and inspecting each of your maintenance providers. Inherent with a risk-based process, you may determine that some of your maintenance providers do not require an on-site 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 determine if the maintenance personnel are following 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 maintenance