AC 120-78A

editorial update 2Historical

Advisory circular · Electronic Signatures, Electronic Recordkeeping, and Electric Manuals

A newer version is currentThis is a historical version. AC 120-78B is the version in force, approved December 11, 2024.
Approved
October 24, 2019
Last reviewed
August 16, 2024
This change
Second Editorial Update to AC 120-78A.
Family
AC 120-78 · 5 versions
Revision
A
14 CFR parts
43, 61, 63, 65, 91, 121, 125, 129, 133, 135, 137, 141, 142, 145, 147, 183
14 CFR sections
§ 129.14

Guidance, not mandatory unless a rule or AD requires it. DRS record last changed November 21, 2025.

Show pages 13–24

Par 4-3 Page 26

(b) Primary Point of Contact (POC). The letter must include the certificate holder’s primary POC for the electronic manual system application process.

(2) Master Manual for Parts 91K, 121, 125, and 135. An application to use an electronic manual system for part 91K, 121, 125, or 135 must include a copy of the proposed master manual as described in subparagraph 4-2o of this AC.

(3) A Description of the Proposed Electronic Manual—Part 133 and 145. An application to use an electronic manual for parts 133 and 145 must include a description of the electronic manual as described in subparagraph 4-2p of this AC.

(4) Manuals Included in the System. The application must state specifically which manuals the certificate holder intends to maintain and distribute electronically:

• Flight Operations Manuals (FOM) by title;

• Ground operations manuals by title;

• Maintenance manuals by title;

• Training program manuals by title;

• Electronic MELs;

• General policy manuals by title; and

• User manuals (e.g., flight planning system and other hardware/software applications) by title.

(5) Distribution to the FAA. The certificate holder must provide a copy of the electronic manuals to the responsible Flight Standards office and provide an explanation of how revisions and future electronic manuals will be distributed to the FAA.

(6) Electronic Access to an MEL. Parts 91K, 121, 125, and 135 require a certificate holder or program manager to have FAA approval and OpSpec authority to provide access to an MEL via electronic means. Certificate holders desiring to provide electronic access to an MEL must specify that in the application and include details on how electronic access will be provided.

b. Demonstration of the System. The FAA will require a certificate holder to demonstrate the electronic manual system. The items requiring demonstration will typically include at least the following:

(1) Hardware and Software Capabilities. The certificate holder should demonstrate how to use the hardware and software by performing simple tasks within the system.

(2) Distribution and Availability. The certificate holder should demonstrate how the manuals will be distributed or made available (depending upon the regulatory requirement) to required personnel electronically.

(3) Information Access Capabilities. The certificate holder should demonstrate how to access manual content via the electronic system.

Par 4-3 Page 27 (and 28)

(4) Prevention of Unauthorized Modification. The certificate holder should demonstrate how the system prevents unauthorized modifications to manual content.

(5) Revision Capabilities. The certificate holder should demonstrate how revisions are posted to electronic manuals.

c. Successful Completion of Application for Approval or Acceptance and Authorization. When a certificate holder successfully completes the approval (applicable only to electronic access to an MEL) or acceptance process, the FAA will authorize the electronic manual system by signing and issuing OpSpec A025.

d. Unsuccessful Application. If the certificate holder fails to submit an acceptable application or fails to successfully demonstrate the manual system process, the responsible Flight Standards office will reject the application and provide an explanation to the certificate holder in writing.

Par 5-1 Page 29 (and 30) CHAPTER 5. VOLUNTARY DISCONTINUANCE BY CERTIFICATE HOLDER

5-1. VOLUNTARY DISCONTINUANCE. If a certificate holder elects to discontinue using electronic signatures, an electronic recordkeeping system, or an electronic manual system, it must inform the appropriate PI or ASI by letter. Once informed, the responsible Flight Standards office will amend the certificate holder’s OpSpec A025 to remove the authorization voluntarily discontinued. Certificate holders that voluntarily discontinue the use of electronic signatures, an electronic recordkeeping system, and/or an electronic manual system must include the following information in their discontinuance letter.

a. Discontinue Electronic Signatures.

(1) The letter from the certificate holder must include the projected date the certificate holder intends to discontinue using the electronic signatures.

(2) The letter must contain a description of how the certificate holder intends to transition from using electronic signatures to using pen-and-ink signatures.

(3) The letter must contain a description of how electronically signed documents and records will be reproduced and retained in accordance with the requirements of 14 CFR in hardcopy form.

(4) If an electronic signature is used in conjunction with electronic recordkeeping, then the electronic signature portion of the recordkeeping system must be removed.

b. Discontinue Electronic Recordkeeping System.

(1) The letter from the certificate holder must include the projected date the certificate holder intends to discontinue using the electronic recordkeeping system.

(2) The letter must contain a description of how the certificate holder intends to transition from electronic records to paper. The description must include how the certificate holder intends to ensure the content of the paper records exactly match the electronic content, including having the required signatures.

c. Discontinue Electronic Manual System.

(1) The letter from the certificate holder must include the projected date the certificate holder intends to discontinue using the system and provide hardcopy manuals, if required by appropriate 14 CFR parts.

(2) The letter must contain a description of how the certificate holder intends to transition from electronic manuals to paper manuals. The transition description should include procedures for the certificate holder to audit the paper manuals by comparing them to the electronic manuals and reconcile any differences.

Par 6-1 Page 31 CHAPTER 6. ADMINISTRATIVE

6-1. QUESTIONS ABOUT THIS AC. If you have questions about the material in this AC or would like to provide feedback, you may contact the Aircraft Maintenance Division at 5th Floor, 950 L’Enfant Plaza, SW., Washington, DC 20024; or by phone at 202-267-1675. For your convenience, the Advisory Circular Feedback Form is the last page of this AC.

6-2. OTHER RELATED REGULATIONS, GUIDANCE, AND READING MATERIAL.

a. Regulatory References (current editions):

• Electronic Signatures in Global and National Commerce Act (E-Sign) (Public Law (PL) 106-229, Title I).

• Government Paperwork Elimination Act (PL 105-277, Title XVII).

• Paperwork Reduction Act (PL 104-13).

• Title 14 CFR Parts 43, 61, 65, 91, 119, 121, 125, 129, 133, 135, 137, 141, 142, 145, and 147.

• Office of Management and Budget (OMB) Circular A-130, Managing Information as a Strategic Resource.

b. FAA Order 8900.1.

c. Part 121 Dispatch and Flight Release Requirements—Electronic Signatures, Amendments, and Disposition. Information regarding electronic signatures on a dispatch or flight release; electronic amendments to a dispatch or flight release; and/or electronic recordkeeping of a dispatch or flight release is contained in Order 8900.1, Volume 3, Chapter 25, Section 1, Basic Requirements and Policy Applicable to All Air Carriers.

d. Part 121 En Route Communication Records. Information on the electronic retention of en route communication records in accordance with part 121, § 121.711 is contained in Order 8900.1, Volume 3, Chapter 25, Section 1.

e. Part 121 and 135 Recordkeeping Systems Acceptance or Approval Process.

Information and guidance to be used by principal inspectors (PI) when accepting or approving certificate holder recordkeeping systems is contained in Order 8900.1, Volume 3, Chapter 31, Section 2, Requirements for Approval, Acceptance, and Authorization.

f. Part 121 and 135 Crewmember and Aircraft Dispatcher Records. Order 8900.1, Volume 3, Chapter 31, Section 3, Crewmember and Aircraft Dispatcher Records, contains detailed information regarding crewmember and aircraft dispatcher records in accordance with the requirements of parts 121 and 135, as applicable.

g. Part 121 and Part 135, § 135.411(a)(2) Maintenance Records. Order 8900.1, Volume 3, Chapter 31, Section 5, Safety Assurance System: Evaluate a Part 121/135 (10 or More) Certificate Holder/Applicant Maintenance Recordkeeping System, contains detailed information regarding the evaluation of an air carrier’s maintenance recordkeeping system.

Par 6-2 Page 32

h. Part 91K Non-CAMP Program Manager’s, Part 125, § 125.247 Certificate Holder’s, and § 135.411(a)(1) Maintenance Records. Order 8900.1, Volume 3, Chapter 31, Section 6, Safety Assurance System: Evaluate a Part 91K Non-CAMP Program Manager’s, § 125.247 Operator’s, and § 135.411(a)(1) Certificate Holder’s Maintenance Records, contains information for Airworthiness inspectors on how to evaluate part 91K non-CAMP and part 135 maintenance records.

i. Part 145. Order 8900.1, Volume 6, Chapter 9, Section 6, Safety Assurance System:

Inspect a Repair Station’s Record System, contains detailed information on repair station electronic signatures and electronic recordkeeping.

j. Operations Specification (OpSpec) A025, Electronic Signatures, Electronic Recordkeeping Systems, and Electronic Manual Systems. Information on how to issue OpSpec A025 is contained in Order 8900.1, Volume 3, Chapter 18, Section 3, Part A Operations Specifications—General, OpSpec/MSpec A025.

k. FAA Order 8000.79, Use of Electronic Technology and Storage of Data (current edition).

l. Related ACs (current editions):

• AC 90-117, Data Link Communications.

• AC 91-78, Use of Class 1 or Class 2 Electronic Flight Bag (EFB).

• AC 91.21-1, Use of Portable Electronic Devices Aboard Aircraft.

• AC 120-64, Operational Use and Modification of Electronic Checklists.

• AC 120-76, Authorization for Use of Electronic Flight Bags.

m. Other Reading Material. OMB Memorandum M-00-15, OMB Guidance on Implementing the Electronic Signatures in Global and National Commerce Act.

6-3. OBTAINING REFERENCE MATERIAL (current editions):

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

• Certificate holders can find Order 8900.1 at http://fsims.faa.gov.

Appendix 1 Page 1 (and 2) APPENDIX 1. SAMPLE LETTER OF INTENT [Requester Letterhead] To: [FAA Flight Standards District Office (FSDO)/certificate management office (CMO) responsible for the requester’s operations] From: [Requester] Date: [Date] Subject: Use of Electronic System – (Signatures/Recordkeeping/Manuals) This letter is to inform you that [requester] intends to use an electronic (signatures and/or recordkeeping and/or manual) system for [describe what the system will be used for]. This system has been established using the guidelines outlined in FAA Advisory Circular (AC) 120-78 (as amended).

NOTE: Certificate holders should use this AC to identify the various requirements for the letter of intent contents.

Company facilities, equipment, and personnel are available for your review at [address] on [date]. Please contact [name] at [telephone] to arrange a visit to review the system and to discuss any FAA concerns.

Sincerely, [Requester]

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 contacting the Flight Standards Directives Management Officer at 9-AWA-AFB-120-Directives@faa.gov.

Subject: AC 120-78A, Electronic Signatures, Electronic Recordkeeping, and Electronic Manuals Date: _____________________ Please check all appropriate line items:

An err or ( proc edural 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: ______________________