AC 120-17B

editorial update

Advisory circular · Reliability Program Methods—Standards for Determining Time Limitations

Approved
July 9, 2026
Last reviewed
July 10, 2026
This change
Editorial update of AC 120-17B.
Cancels
AC120-17B
Family
AC 120-17 · 3 versions
Revision
B
14 CFR parts
5, 91, 119, 121, 135

Guidance, not mandatory unless a rule or AD requires it. DRS record last changed July 10, 2026.

Show pages 36–47
Page 48OCROpen in PDF

Appendix G APPENDIX G. LIGHTNING/HIGH INTENSITY RADIATED FIELDS (L/HIRF) TASKS Note 1. Coordination with OEM is L/HIRF Task ' recommended. L/HIRF protection may include:

- Wires, shields, connectors, bonding straps, raceways between connectors.

- L/HIRF protection within conduit or Review TCH ICA heat shrink or other covering. rules.

- Non-metallic structure with conductive mesh and/or antistatic coatings.

Ensure TCH ICA rules are followed, if applicable.

Ensure data selection criteria conforms with guidance in this AC (or as accepted by carrier's CMO).

Perform analysis of appropriate data. 2 Note 2: Analysis should consider:

- The environment and effects of corrosive products, condensation, temperature, and vibration on the protection. Does the

- Susceptibility of damage during maintenance or analysis operations (e.g., where connectors could be stepped substantiate a task interval on, or effects of deicing fluid on a connector during and/or scope revision that maintains acceptable levels winter operations.

- Scheduled maintenance findings associated with protection? of L/HIRF bonding straps, lightning wicks, tank plates wiring/ connector bonding, etc.

Yes Revise task scope, type, and/or interval.

End G-1

Page 49OCROpen in PDF

Appendix H APPENDIX H. OPERATOR PROGRAMS AND APPEARANCE Note 1. This decision tree applies to Operator Program tasks developed and implemented by and Appearance the operator, such as: Tasks 1

- Tasks that support other tasks;

- Administrative support tasks;

- Branding/image objectives; and

- Cabin appearance and cleanliness standards established by the operator. task a response Is this Appendix A; or other defined or is it otherwise related to a deficiency in the Yes- analysis process operator's CAMP?

No Based on risk, determine the data set and analysis needed to evaluate the proposed change.

Does the Is the analysis anticipated impact +No substantiate a acceptable? revised or deleted task?

Yes Delete or revise task scope, type, and/or accomplishment interval End H-1

Page 50OCROpen in PDF

Appendix I APPENDIX I. REGULATORY SOURCED REQUIREMENTS Regulatory Sourced Task Note 1. Examples include:

AD, CM Rs, AL, AL, FTS tasks.

Does the Ensure regulatory regulatory authority or authority or source source requirement contain specific -Yes-• requirements are followed.

instructions for task adjustment?

No Ensure data selection criteria conforms with guidance in this AC (or as accepted by carrier's CMO).

Note 2. Relative to the targeted failure mode and original intent.

Refer to MSG-3 section 2-3-7.1 analysis substantate Does (Table 2-3-7.1, Criteria for Task adjustment of the task Selection) for applicability and safety interval and remain effectiveness guidance. No effective? * Coordinate with the TCH when data from the MSG-3 task analysis is necessary to perform the evaluation.

Submit proposal to the regulatory authority/ source requirement holder.

Was approval obtained from the regulatory authority/ source requirement holder?

Revise task as approved.

End I-1

OMB Control Number: 2120-0746 Expiration Date:12/31/2027 Advisory Circular Feedback Form Paperwork Reduction Act Burden Statement: A federal agency may not conduct or sponsor, and a person is not required to respond to, nor shall a person be subject to a penalty for failure to comply with a collection of information subject to the requirements of the Paperwork Reduction Act unless that collection of information displays a currently valid OMB Control Number. The OMB Control Number for this information collection is 2120-0746. Public reporting for this collection of information is estimated to be approximately 20 minutes per response, including the time for reviewing instructions, searching existing data sources, gathering, and maintaining the data needed, completing, and reviewing the collection of information.

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If you find an error in this Advisory Circular, have recommendations for improving it, or have suggestions for new items/subjects to be added, you may let us know by emailing this form to the Flight Standards Directives Management Officer at 9-AWA-AFB-120-Directives@faa.gov.

Subject: AC 120-17B, Reliability Program Methods—Standards for Determining Time Limitations Date: _____________________ Please mark all appropriate line items:

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Submitted by: Date: ______________________ FAA 1320-73 (01/25) SUPERSEDES PREVIOUS EDITIONS