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• Part 26 , Continued Airworthiness and Safety Improvements for Transport Category Airplanes.
• Part 26 Subpart A, General.
• Part 26, § 26.11, Electrical Wiring Interconnection Systems (EWIS) Maintenance Program.
• Part 43, § 43.13, Performance Rules (General).
• Part 121 Subpart AA, Continued Airworthiness and Safety Improvements.
• Part 121, § 121.1111, Electrical Wiring Interconnection Systems (EWIS) Maintenance Program.
• Part 129 Subpart B, C ontinued Airworthiness and Safety Improvements.
• Part 129, § 129.111, Electrical Wiring Interconnection Systems (EWIS) Maintenance Program.
• SFAR 88, Fuel Tank System Fault Tolerance Evaluation Requirements.
1.7 Related Reading Materials (current editions):
1.7.1 ACs. You c an locate each of the following ACs on the FAA website at https://www.faa.gov/regulations_policies/advisory_circulars and on DRS:
• AC 25-8, Auxiliary Fuel System Installations.
• AC 25-19, Certification Maintenance Requirements.
• AC 25-27, Development of Transport Category Airplane Electrical Wiring Interconnection Systems Instructions for Continued Airworthiness Using an Enhanced Zonal Analysis Procedure.
• AC 25.981- 1, Fuel Tank Ignition Source Prevention Guidelines.
• AC 25.981-2, Fuel Tank Flammability Reduction Means.
• AC 25.1701-1, Certification of Electrical Wiring Interconnection Systems on Transport Category Airplanes.
• AC 26- 1, Part 26, Continued Airworthiness and Safety Improvements.
• AC 120-16, Air Carrier Maintenance Programs.
• AC 120-94, Aircraft Electrical Wiring Interconnection Systems Training Program.
• AC 120-97, Incorporation of Fuel Tank System Instructions for Continued Airworthiness into Operator Maintenance and/or Inspection Programs.
• AC 121- 22, Maintenance Review Boards, Maintenance Type Boards, and OEM/TCH Recommended Maintenance Procedures.
• AC 129- 4, Maintenance Programs for U.S.- Reg istered Aircraft Operated Under 14 CFR Part 129.
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1.7.2 FAA Orders.
• Order 8110.54, Instructions for Continued Airworthiness Responsibilities, Requirements, and Contents.
• Order 8110.104, Responsibilities and Requirements for Implementing Part 26 Safety Initiatives.
1.7.3 I ndustry References. The use of the term “ATA coded sections” within this AC refers to the Air Transport Association of America (ATA) codes that are standardized for each aircraft system. The ATA changed its name to Airlines for America (A4A) in 2011;
however, the acronym “ATA” is still used for coded aircraft systems. The acronyms “ATA” and “A4A” are considered interchangeable. The alternate format for aircraft system coding is the Joint Aircraft System/Component (JASC) Code. For additional information on JASC coding, refer to the FAA JASC Code Table and Definitions, which is accessible via https://sdrs.faa.gov/documents/JASC_Code.pdf. Refer also to A4A Maintenance Steering Group – 3rd Task Force (MSG-3), Operator/Manufacturer Scheduled Maintenance Development, and DAH-developed publications.
1.8 FAA Policy Statements (available for download at https://drs.faa.gov).
1.8.1 PS-ANM110-7-12-2005, Safety—A Shared Responsibility—New Direction for Addressing Airworthiness Issues for Transport Airplanes.
1.8.1.1 On July 12, 2005, the FAA issued policy statement PS-ANM110-7-12-2005.
The policy states, in part: “Based on our evaluation of more effective regulatory approaches for certain types of safety initiatives…the FAA has concluded that we need to adopt a regulatory approach recognizing the shared responsibility between DAHs and operators. When we decide that general rulemaking is needed to address an airworthiness issue, and believe the safety objective can only be fully achieved if the DAHs provide operators with the necessary information in a timely manner, we will propose requirements for the affected DAHs to provide that information…”
1.8.1.2 Section 26.11 implemented this policy for the EAPAS/FTS rule.
Section 26.11 requires the design approval holders (DAH) to develop ICA for EWIS for certain transport category airplanes and submit them for review and approval to the responsible Aircraft Certification Service office.
1.8.2 PS-AIR-100-2009-05-27, Adding Part 26 to Type Certificate Data Sheets and Supplemental Type Certificates. On October 22, 2007, 14 CFR adopted a new part 26, Continued Airworthiness and Safety Improvements for Transport Category Airplanes.
1.8.3 PS -AIR-100-2007-12-27B, Enhanced Airworthiness Program for Airplane Systems (EAPAS) Supplemental Type Certificate (STC) Limitation. On June 10, 2009, the FAA issued revised policy statement PS-AIR-100-2007-12-27B. This memo was revised to remove the paragraph on certification basis, which is included in a separate policy memorandum, PS-AIR-100-2009-05-27.
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1.8.4 ANM-08-113-001, Policy Statement on Clarification of Maximum Payload Capacity Definition in Design Approval Holder Rules. On September 12, 2008, the FAA issued policy statement ANM-08-113-001. This policy states that the “maximum payload capacity criterion is used, along with other criteria, to determine whether a rule is applicable to a DAH. However, there has been confusion on the use and definition of the term. This policy memorandum clarifies the maximum payload capacity criterion when used with regard to these DAH rules and their corresponding operational rules.”
1.9 AC Feedback Form. For your convenience, the AC Feedback Form is the last page of this AC. Note any deficiencies found, clarifications needed, or suggested improvements regarding the contents of this AC on the Feedback Form.
2-1 CHAPTER 2. ENHANCED AIRWORTHINESS PROGRAM FOR AIRPLANE
SYSTEMS (EAPAS) REQUIREMENTS
2.1 Requirements. This advisory circular (AC) provides guidance to support operator compliance with the electrical wiring interconnection system (EWIS) maintenance program requirements contained in the Enhanced Airworthiness Program for Airplane Systems/Fuel Tank Safety (EAPAS/FTS) Rule. Title 14 of the Code of Federal Regulations (14 CFR) part 121, § 121.1111 and part 129, § 129.111 require operators to incorporate into their maintenance program inspections and procedures for EWIS contained in instructions for continued airworthiness (ICA) approved by the Federal Aviation Administration (FAA) responsible Aircraft Certification Service office. The design approval holder (DAH) develops and revises the ICA using AC 25-27, Development of Transport Category Airplane Electrical Wiring Interconnection Systems Instructions for Continued Airworthiness Using and Enhanced Zonal Analysis Procedure.
The ICA for the EWIS consist of inspections and procedures to accomplish those tasks, and may include, in addition, maintenance of other natures (e.g., overhaul, repair, etc.), intervals, and “protections and caution” instructions and information. (Refer to 14 CFR part 1 for the definition of “maintenance” and “preventive maintenance.”)
2.2 Description of EWIS ICA Required by 14 CFR Part 26, § 26.11.
2.2.1 Overview. The EWIS ICA required by § 26.11 are developed in accordance with 14 CFR part 25 appendix H, § H25.5(a)(1) and (b). These ICA are:
1. Maintenance tasks to reduce the likelihood of ignition sources and accumulation of combustible material. There may be inspections under the form of a zonal General Visual Inspection (GVI), standalone GVI, Detailed Inspection (DET), overhauls, repairs, replacements, or a combination of these;
2. Procedures to effectively clean the EWIS components of combustible material if there is not an effective maintenance task to reduce the likelihood of combustible material accumulation; and
3. Instructions for protections and caution information to minimize contamination and accidental damage to EWIS, as applicable, during the performance of maintenance or alteration. The EWIS ICA can include other instructions (refer to §§ H25.4 and H25.5(a)(2) through (5)).
2.2.2 M ultiple Items and Components . The EWIS ICA include multiple items and can be, and almost always are, comprised of several different components. All of these items and components define a particular EWIS ICA. These items and components are in multiple DAH-produced documents.
2.2.2.1 These EWIS ICA items include:
1. Type of task (e.g., overhaul, replacement, standalone GVI, DET, or standard zonal GVI).
2. Task interval (e.g., every 16,000 flight cycles or 3,000 days).
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3. Airplane zone identification for airplanes with a zonal program
(e.g., Zone 201).
4. Task description (e.g., Inspect (General Visual) all exposed EWIS in the wheel well).
Note: The gear is extended with the handle down and gear locked in the down position and doors in open position).
5. Airplane applicability. Some models within the same family of airplanes may have differing maintenance requirements based on available options
(e.g., freighter versus passenger version engine types).
6. Task procedure(s) as described in the referenced Aircraft Maintenance Manual (AMM) or other documents that contain the procedure(s). These are the actual instructions on how to perform the GVI, DET, restoration/cleaning tasks that support the task description listed in the Maintenance Review Board Report (MRBR) and Maintenance Implementation Document (MID), and maintenance tasks that support the task description.
7. Supporting task procedure(s), if any, necessary to perform the task procedure in any other document referenced by the task procedure.
8. Instructions for protections and caution information that will minimize contamination and accidental damage to the EWIS (these can appear in different places, such as in the AMM or in the Standard Wiring Practice Manual (SWPM)/Electrical Standard Practices Manual (ESPM)). This information, if contained in the SWPM/ESPM (or other similar documents), should be in its chapter 20. Sometimes, this information is repeated in the standard practices chapter 20 of the AMM. In any case, it is general protections and caution information, and it is not expected that unique procedures will be developed for individual EWIS ICA for a particular airplane model or models produced by the same manufacturer.
The AMM or SWPM/ESPM will reference any protections and caution information specific to the EWIS ICA.
2.2.2.2 As an example, the EWIS ICA components can be located in one or more of the following documents:
• Document required by § H25.5(b);
• Maintenance Review Board Report (MRBR);
• Maintenance Planning Document (MPD);
• Maintenance Implementation Document (MID);
• Aircraft Maintenance Manual (AMM);
• Standard Wiring Practice Manual (SWPM);
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• Electrical Standard Practices Manual (ESPM) (a term used by some type certificate holders (TCH)); or
• Standalone ICA document produced by a Supplemental Type Certificate (STC) applicant.
2.2.3 EWIS Source Document. Section H25.5(b) states that the EWIS ICA developed in accordance with the requirements of § H25.5(a)(1) must be in the form of a document appropriate for the information provided, and must be easily recognizable as the EWIS ICA or specifically reference other sections of the EWIS ICA that contain this information. This document is referred to as the source document. The form is at the discretion of the DAH, as long as it meets the requirements of §§ H25.2 and H25.5(b).
The entire EWIS ICA can be in the source document, or the source document can point to a series of other documents, such as the MRBR, MPD, MID, AMM, or SWPM/ESPM, which contain the EWIS ICA.
Note: The source document referenced above is approved by the responsible Airc raft Certification Service office. The operational rules require operators to incorporate into their maintenance program EWIS ICA approved by the responsible Aircraft Certification Service office. The source document provides the information necessary for the operator to comply with §§ 121.1111 and 129.111.
2.2.4 Controlling Reference Numbers. C ontrolling reference numbers for the individual EWIS ICA tasks are listed in the MRBR, MPD, MID, or other maintenance documents. An example of a controlling reference number in an MRBR is “MM/MPD ref.
20-XXX-XX.” This number correlates to a cross-reference number in the source document and the AMM, which is the actual maintenance task with all associated instructions to accomplish it. The DAH may refer to these reference numbers as Maintenance Review Board (MRB) reference, AMM/MPD reference, Maintenance Significant Items (MSI) reference, task number, etc. It can vary. The TCH may consider one or all of the reference numbers part of the EWIS ICA. The DAH will identify all reference numbers necessary to fully track and identify the EWIS ICA. All reference numbers considered necessary to fully identify and track the EWIS ICA should be considered part of the EWIS ICA.
2.2.5 DAH Revi sions to EWIS ICA. The DAH will revise the source document in order to account for any new or revised EWIS inspection or procedures required by § H25.5(a)(1) and developed due to production changes, or design changes mandated by an Airworthiness Directive (AD). They will provide the revised source document to operators after the document has been approved by the responsible Aircraft Certification Service office.
2.3 EWIS ICA De velopment Required by § 25.1729. In addition to the EWIS ICA that are required and developed under § 26.11 for existing in service airplanes, there will also be the EWIS ICA developed under § 25.1729 for new airplane type certificates (TC), or when 14 CFR part 21, § 21.101 requires the holder of an amended TC or an STC to comply with a corresponding amendment to part 25 that was issued on or after the date of
2-4 the applicable part 26 provision. Section 21.101 is referred to as the “Changed Product Rule.” The EWIS ICA required by § 25.1729 are developed under §§ H25.4 and H25.5.
Simply stated, an operator can have airplanes that have the EWIS ICA developed under § 26.11 or, if applicable, EWIS ICA developed under § 25.1729, which includes § H25.5 and any mandatory replacement times for EWIS components.
2.4 DAH Activities for Compliance with § 26.11. The DAH is required to develop ICA for the “representative airplane’s” EWIS according to § 26.11, as follows:
2.4.1 TCH. The TCH is required to develop the EWIS ICA for the “representative airplane” in accordance with § 26.11(b). The purpose was to ensure that all variations of the EWIS used in production were reviewed and appropriate ICA were developed. These EWIS ICA were developed in accordance with § H25.5(a)(1) and (b) in effect on December 10, 2007, for each affected type design. The TCH submits those ICA for review and approval by the responsible Aircraft Certification Service office.
Note: TCHs with § 25.1729 i n their certification basis will develop the EWIS ICA in accordance with §§ H25.4 and H25.5.
2.4.2 TC/STC Holders. T C/STC holders are only required to develop the EWIS ICA in compliance with § 26.11(c) or, if required or elected, in compliance with part 25 appendix H, § 25.1729 if the application date for the STC or change to an existing TC/STC was before December 10, 2007, and the FAA issued the certificate on or after December 10, 2007. Applicants for STCs (including changes to existing STCs) or amended TC holders applications filed on or after December 10, 2007, are also required to develop and submit EWIS ICA in compliance with § 26.11 or, if required or elected, in compliance with § 25.1729 for review and approval to the responsible Aircraft Certification Service office.
Note: Amended TC/S TC holders with § 25.1729 in their certification basis will develop the EWIS ICA in accordance with §§ H25.4 and H25.5.
2.5 Why the EWIS ICA Approval is Necessary. While there may be DAH or operator created ICA that appear to be acceptable, before they are applied, the responsible Aircraft Certification Service office must review and approve the EWIS ICA. The development of the EWIS ICA requirements can be complex, requiring qualitative engineering and maintenance assumptions. Approval will help ensure standardized application of these assumptions (e.g., zone density, zone size, potential effects of fire, environmental effects, etc.) and ensure that important information such as wire identification requirements and EWIS separation requirements developed during airplane certification are correctly and logically documented in the airplane’s ICA documents. It will also ensure that the data/documents delivered to the operators will be standardized to the extent required by the EWIS ICA requirements.
2.6 TCH-Developed EWIS Recommended Maintenance Requirements. EWIS ICA are developed in accordance with §§ H25.4 and H25.5. The responsible Aircraft Certification Service office approves all of these EWIS ICA. The TCH can develop the EWIS ICA in
2-5 accordance with § 26.11(b) or (c) by showing compliance with § H25.5(a)(1) and (b); or in accordance with § 25.1729 by showing compliance with §§ H25.4 and H25.5; or by utilizing an existing document for scheduled tasks and the intervals for performing those tasks and procedures, the Maintenance Steering Group – 3rd Task Force (MSG-3) logic contained in the Airlines for America (A4A) Operator/Manufacturer Scheduled Maintenance Development Document (MSG-3), or any other acceptable method of compliance with §§ H25.4 and H25.5 and AC 25-27. The EWIS ICA will be identified as the EWIS ICA as required by § H25.5(b) in the source document developed by the TCH.
As stated earlier in this AC, the TCH should:
1. Develop a source document that contains all of the EWIS ICA data required by § H25.5(a)(1);
2. Develop a source document that references other maintenance documentation that contains the EWIS ICA data required by § H25.5(a)(1); or
3. Utilize an existing document (such as the MRBR, MPD, or MID) to provide the data or the references specified in items 1 and 2 above, respectively.
Note: With reference to TCH Service Bulletins (SB) that affect the EWIS, the FAA expects that the TCH will identify protections and caution information in a manner or form that conveys the information to the operator. For example, one TCH states in every SB that affects the EWIS this cautionary statement: keep the work area, wires, and electrical bundles clean of metal particles or contamination when you use tools. Unwanted material, metal particles, or contamination caught in wire bundles can cause damage to the bundles. Damaged wire bundles can cause sparks or other electrical damage.
2.6.1 Overview. The EWIS ICA developed from application of the en hanced zonal analysis procedure (EZAP) should be located in the systems and powerplant section under Air Transport Association of America (ATA) 20, and the zonal inspection program section of the airplane’s MRBR, MPD, MID, or a source document. They consist of recommended maintenance tasks, task intervals, and instructions/procedures to accomplish the tasks.
With respect to inspection tasks, the inspection can be a zonal GVI, standalone GVI, DET, or a combination of these. The TCH selects task intervals that are adequate to maintain the airplane airworthiness in order to provide operators with a means to properly maintain the EWIS, while still allowing flexibility for the operators to schedule maintenance tasks within their maintenance programs.
2.6.2 Location.
2.6.2.1 All of the EWIS ICA for which compliance is recommended will be in the source document, or the source document will reference other document locations.
2.6.2.2 Operators must incorporate into their maintenance program EWIS ICA that have been approved by the responsible Aircraft Certification Service office.
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2.6.3 Instructions and Procedures.
2.6.3.1 The instructions/procedures to carry out the EWIS tasks will be contained in the AMM, SWPM, and ESPM.
2.6.3.2 Operators should incorporate instructions/procedures that have been approved in their maintenance program/manuals, work cards, job/task cards, Engineering Authorizations/Engineering Orders (EA/EO), etc. It is especially important that the task descriptions, job accomplishment instructions, task cards, job/task cards, etc. contain all the instructions and procedures that support the EWIS task.
2.6.4 Protections and Caution Instructions and Information. The EWIS ICA also includes protections and caution instructions and information that will minimize contamination and accidental damage to the EWIS during the performance of maintenance, alterations, or repairs. Inspections of other airplanes after the Boeing 747 and MD-11 accidents showed that contamination of wire bundles with metal shavings, dust, and fluids were common conditions in representative examples of the aging fleet of transport airplanes.
These contaminants could damage the EWIS and also provide fuel for an electrical fire.
The TCH has developed these protections and caution instructions and information to support the EWIS maintenance program for the airplane. These protections and caution instructions and information will be in the AMM, SWPM and ESPM. Only those sections affected by the incorporated protections and caution instructions and information to support the EWIS are approved, not the entire manual.
2.7 STC Holder-Developed EWIS ICA. Section 26.11 applies to applicants for STCs (including changes to existing STCs) if the date of application was before December 10, 2007, and the STC was issued on or after that date. Unless compliance with § 25.1729 is required or elected, the rule also applies to applications for STCs (including changes to existing STCs) filed on or after December 10, 2007.
2.8 STC Limitation. Part 26 does not prohibit issuing an STC even if the STC applicant has not yet met the requirements of that section. In this case, the FAA will add a limitation to the STC. FAA engineering policy memo PS-AIR-100-2007-12-27B, Enhanced Airworthiness Program for Airplane Systems (EAPAS) Supplemental Type Certificate (STC) Limitation, dated June 10, 2009, describes how and when the FAA will do this. You can download an electronic copy at https://drs.faa.gov.
2.8.1 Limitation Statement. It is important for the operator to understand that this is a limitation on the STC applicant and not the operator. The following statement (as described in PS-AIR-100-2007-12-27B) should be added to the Limitation Section of the STC when the EWIS ICA evaluation has not been completed at the time of the STC issuance (provided it is issued prior to June 7, 2010). The goal of the limitation is (1) to not allow any installations after August 30, 2010, if an STC applicant has not met the § 26.11 EWIS requirements; and (2) to not ground any airplanes that already have the STC installed.
2-7 “This modification may not be installed after August 30, 2010 unless (1) previously approved electrical wiring interconnection system (EWIS) instructions for continued airworthiness (ICA) have been evaluated and determined to be adequate for this installation by the FAA, or (2) revised EWIS ICA have been approved by the responsible Aircraft Certification Service office. (Refer to § 26.11.)”
2.8.2 I nstallation After August 30, 2010. In order for the operator to install the STC after August 30, 2010, the operator will need to have one of the following:
1. A letter from the responsible Aircraft Certification Service office stating that the previously approved EWIS ICA have been evaluated and shown to be adequate for the modification. The operator should request this letter from the responsible Aircraft Certification Service office to ensure that the STC has been evaluated in accordance with § 26.11(c)(1) and (2) prior to installation; or
2. Revised EWIS ICA that the responsible Aircraft Certification Service office has approved for the STC modification. The revised EWIS ICA should be provided to the operator by the STC holder.
Note: Once the STC holder has met the § 26.11 requirements, the STC does not need to be revised to remove the statement. However, if the STC needs to be updated/amended, the limitation may be removed at that time.
2.8.3 E xisting STCs After August 30, 2010. As stated above, this is a limitation on the STC applicant, not on the operator. Operators can continue to operate their airplanes with the existing STC after August 30, 2010. The operator has no obligation under the operation rules (§§ 121.1111 and 129.111) to develop the EWIS ICA for the existing STC. If the STC holder provides the EWIS ICA that have been approved by the responsible Aircraft Certification Service office for the previously incorporated STC (STC installed after the effective date of the rule), the operator should assess them for incorporation into its maintenance program.
Note: If a n STC limitation remains, no person may approve for return to service an airplane modified in accordance with the installation instructions of the STC after August 30, 2010, even if an operator operates airplanes that had the design change installed on the same airplane model prior to August 30, 2010.
2.9 Requirement to Ensure Compatibility Between Fuel Tank System and EWIS ICA.
Section 26.11 requires a review by the TC and STC holders of any fuel tank system ICA developed to comply with Special Federal Aviation Regulation (SFAR) 88, Fuel Tank System Fault Tolerance Evaluation Requirements. This ensures compatibility with the EWIS ICA and minimizes duplication of requirements between them. Fuel tank wiring is part of the aircraft’s EWIS. The fuel tank system maintenance requirements might be more specific than those for wiring in general and might contain additional requirements.
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2.9.1 TC and STC Holder Review. The DAH will review ICA to ensure that any maintenance tasks for the EWIS do not compromise fuel tank system wire requirements, such as separation or configuration specifications. Operators need to be aware that separation and configuration of the EWIS, especially when performing a repair or alteration to the EWIS or fuel tank system wiring, may be critical.
Note: The responsible Aircraft Certification Service office must approve any ope rator-proposed changes to separation and configuration of the EWIS or fuel tank system wiring. The operator must submit its proposed changes with supporting technical justification/data through the principal inspector (PI). The PI adds comments (if any) and forwards the proposed changes to the responsible Aircraft Certification Service office for approval.
2.9.2 Fuel Tank System and EWIS ICA Location. The responsible Aircraft Certification Service office approves the TC and STC ICA for EWIS. With respect to the recommended repetitive maintenance instructions, the TCH will typically list the EWIS and fuel tank system tasks and intervals in its manual or section of ICA for the airplane that is required to comply with § H25.3(b)(1). They are identified as the EWIS ICA or the EWIS/SFAR 88 ICA. The STC holder will typically list its ICA in the STC document it provides.
2.9.3 Example. T he following table is an example of how a TCH has identified an integrated EWIS/SFAR 88 task within its manual or section of ICA for the airplane that is required to comply with § H25.3(b)(1). STC holders may identify them differently and include them in the ICA section of their documents. Each task is identified as an EWIS task or SFAR 88 task. An integrated task will be identified as an EWIS/SFAR 88 task. Operators should identify the EWIS tasks and the integrated EWIS/SFAR 88 tasks in their maintenance program so as not to lose their identity as part of an approved ICA.
1. Column 1 identifies the task number, in this case 20-XXX. The task number 20-XXX is only an example for illustration purposes in this AC. An actual TCH task number will probably contain six or more numbers, such as 20-XXX-XX. Some may also be in ATA 28, so the task may be 28-XX-XX.
2. Column 2 is the task category, which is a DET.
3. Column 3 is the task interval, 6C.
4. Column 4 is airplane applicability.
5. Column 5 is a description of the task and, in this case, is an integrated EWIS/SFAR 88 task.
2-9 Table 2-1. Integrated Enhanced Airworthiness Program for Airplane Systems/Fuel Tank Safety Task
1. It em 2. Task Category 3. Task Interval 4. Airplane Applicability 5. Task Description 20-XXX * DET 6C All Inspect exposed EWIS/FQIS, etc. EWIS/SFAR 88 *Subparagraph 2.9.3
2.10 Operator-Developed EWIS ICA. The FAA recognizes that some operators may want to and can develop (using AC 25-27) their own EWIS ICA compliant with § H25.5(a)(1) and (b) (e.g., when their maintenance programs have not been developed using MSG-3).
Operators can incorporate into their maintenance programs the TC or STC holder’s EWIS ICA, or their own ICA (as a complement or an alternative) once these EWIS ICA are approved by the responsible Aircraft Certification Service office.
Note: Important information for the operator: If the operator develops its own EWIS ICA, the responsible Aircraft Certification Service office must approve them. The operator must forward its proposed EWIS ICA through the PI. The PI adds comments (if any) and forwards the proposed EWIS ICA to the responsible Aircraft Certification Service office for approval. Operators must incorporate into their maintenance program EWIS ICA that have been approved by the responsible Aircraft Certification Service office.