AC 120-78B

U .S. Department of Transportation Federal Aviation Administration Advisory Circular Subject: Electronic Signatures, Electronic Recordkeeping, and Electronic Manuals Date: 12/11/24 Initiated by: AFS-300/ AFS-200 AC No: AC 120-78B Change:

This advisory circular (AC) provides standards and guidance for electronic signatures, electronic recordkeeping, and electronic manual systems. The standards and guidance contained in this AC apply to those signatures, records, and manuals required by Title 14 of the Code of Federal Regulations (14 CFR) when those items are in a digital or electronic format. This AC describes an acceptable means, but not the only means, for a certificate holder to utilize an electronic signature, electronic recordkeeping, and electronic manual systems. The contents of this document do not have the force and effect of law and are not meant to bind the public in any way, and the document is intended only to provide information to the public regarding existing requirements under the law or agency policies.

T imothy R. Adams for Lawrence Fields Executive Director, Flight Standards Service

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CONTENTS Paragraph Page

Chapter 1. General Information1-1

1.1 Purpose of This Advisory Circular (AC)1-1

1.2 Audience1-1

1.3 Where You Can Find This AC1-1

1.4 What This AC Cancels1-1

1.5 Applicability1-1

1.6 Scope1-2

1.7 Background1-3

1.8 Definitions1-4

1.9 Approval, Acceptance, and Authorization1-5

Chapter 2. Electronic Signatures2-1

2.1 Electronic Signatures2-1

2.2 Electronic Signature Process2-2

2.3 Electronic Signature Authorization2-5

Chapter 3. Electronic Recordkeeping3-1

3.1 Electronic Records3-1

3.2 Electronic Recordkeeping Systems3-2

3.3 Electronic Recordkeeping Authorization3-5

Chapter 4. Electronic Manual Systems4-1

4.1 Electronic Manuals4-1

4.2 Special Considerations in Displaying Information4-1

4.3 Electronic Manual Systems4-2

4.4 Electronic Manual Authorization4-6

Chapter 5. Voluntary Discontinuance by Certificate Holder5-1

5.1 Voluntary Discontinuance5-1

Chapter 6. Ad ministrative6-1

6.1 Questions About This AC6-1

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6.2 AC Feedback Form6-1

6.3 Other Related Regulations, Guidance, And Reading Material

(current editions)6-1

Appe ndix A. Sample Letter of IntentA-1

1-1 CHAPTER 1. GENERAL INFORMATION

1.1 Purpose of This Advisory Circular (AC). This AC provides approval, acceptance, and authorization guidelines for electronic signatures, electronic recordkeeping systems, and electronic manual systems. The guidelines in this AC apply where signatures, records, and/or manuals are required under Title 14 of the Code of Federal Regulations (14 CFR) parts 5, 43, 61, 63, 65, 91, 121, 125, 133, 135, 137, 141, 142, 145, and 147 are in a digital or electronic format. The contents of this document do not have the force and effect of law and are not meant to bind the public in any way, and the document is intended only to provide information to the public regarding existing requirements under the law or agency policies.

1.2 Audience. The audience for this AC is entities regulated under 14 CFR as described in paragraph 1.5 below.

1.3 Where You Can Find This AC. You can find this AC on the Federal Aviation Administration’s (FAA) website at https://www.faa.gov/regulations_policies/advisory_cir culars and the Dynamic Regulatory System (DRS) at https://drs.faa.gov.

1.4 What This AC Cancels. AC 120-78A, Electronic Signatures, Electronic Recordkeeping, and Electronic Manuals, dated June 22, 2016, is canceled.

1.5 Applicability. This AC applies to the following regulated entities, which for the purposes of this AC will be identified as “certificate holders”:

• Foreign air carriers or foreign persons operating a U.S.-registered aircraft in accordance with 14 CFR § 129.14.

• Certificate holders conducting operations in accordance with 14 CFR part 121, 125 (including part 125 Letter of Deviation Authority (LODA) holders), 133, 135, or 137.

• Fractional ownership program managers conducting operations in accordance with 14 CFR part 91 subpart K (part 91K).

• Operators conducting operations in accordance with 14 CFR part 91.

• Airmen certification course operators and training providers who provide instruction and evaluation in accordance with 14 CFR part 61, 63, 65, 141, or 142.

• Persons performing airmen certification in accordance with 14 CFR part 61, 63, 65, 141, or 142.

• Individuals performing maintenance or preventive maintenance in accordance with 14 CFR part 43.

• Repair stations operating in accordance with 14 CFR part 145.

• Aviation Maintenance Technician Schools (AMTS) who provide instruction and evaluation in accordance with 14 CFR part 147.

1-2 Note: The scope of this AC is intended for entities regulated by the FAA’s Flight Standards Service (FS) and is not intended to apply to production, design, or manufacturing authority (e.g., type certificate (TC), Supplemental Type Certificate (STC), Parts Manufacturer Approval (PMA), etc.) signature, recordkeeping, and manual requirements established by the FAA’s Aircraft Certification Service (AIR).

1.6 Scope. Signatures, records, and manuals as discussed in this AC generally apply to the following categories (this list is not intended to be all inclusive).

1.6.1 Signatures:

• Certification of Training or Qualification;

• Pilot Logbooks;

• Fitness for Duty;

• Flight/Dispatch Release;

• Load Manifests;

• Operational Control Briefing;

• Preflight Risk Analysis Worksheet;

• Maintenance Logbook;

• Airworthiness Release;

• Maintenance Performed;

• Continuous Airworthiness Maintenance Program (CAMP); and

• Extended Operations (ETOPS) Predeparture Service Check (PDSC).

1.6.2 Records:

• Training and Qualification;

• Crewmember;

• Dispatcher;

• Flight, Duty, and Rest;

• Dispatch Release;

• Flight Release;

• Load Manifest;

• Communication;

• Maintenance Records;

• Maintenance Log;

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• Airworthiness Release; and

• Safety Management System (SMS) Records required by 14 CFR § 5.97.

1.6.3 Manuals:

• Flight Operations (including dispatch, flight following, and onboard/cabin);

• Ground Operations (including ground and passenger handling);

• Certificate Holder Aircraft Performance Manuals (Airplane Flight Manual (AFM) and Weight and Balance (W&B) information, etc.);

• Training Program;

• Maintenance (including overhaul, standard practices, etc.);

• Minimum equipment list (MEL);

• General Policy and Procedures; and

• User (e.g., flight management system (FMS), flight planning system, etc.).

1.7 Background.

1.7.1 Electronic Signatures and Electronic Records. Public Law (PL) 105-227, Title XVII, Government Paperwork Elimination Act; PL 106-229, Electronic Signatures in Global and National Commerce Act (E-Sign Act); and Office of Management and Budget (OMB) Memorandum M-00-15, OMB Guidance on Implementing the Electronic Signatures in Global and National Commerce Act, encourage the use of electronic records, signatures, and alternative information technologies, and allow Government agencies to develop performance standards for their use. OMB Circular A-130, Managing Information as a Strategic Resource, provides general guidance for federal organizations regarding the use of electronic signatures in connection with electronic records and electronic transactions. The use of these electronic technologies also supports the goals of PL 107-198, Small Business Paperwork Relief Act of 2002. This AC provides guidelines on meeting the FAA’s performance standards developed in accordance with the listed PLs and OMB memorandum.

1.7.2 Electronic Manuals. On October 29, 2002, the FAA first published standards and guidance for electronic signatures, electronic recordkeeping, and electronic manual systems in this AC. On May 30, 2023, the FAA amended its 14 CFR regulations for manual requirements to accommodate technology (refer to 88 FR 34437, Updating Manual Requirements to Accommodate Technology, dated May 30, 2023). In 88 FR 34437, Section IV, Discussion of the Final Rule, the FAA stated that, “for revision control purposes, there needs to be a method to confirm that employees are using the most current manual when performing their job duties. The FAA determined that the most straightforward way to confirm use of the correct version is to display the date of revision while giving the air carrier the flexibility of determining where to put that date.”

Accordingly, this AC contains standards and guidelines for electronic manual systems

1-4 that provide an acceptable means, but not the only means, to use an electronic manual system.

1.8 Definitions. The following terms are used in this AC:

1.8.1 Authentication. The means by which a system validates the identity of an authorized user.

These may include a password, a personal identification number (PIN), a cryptographic key, a smart card, etc.

1.8.2 Computer-Based Recordkeeping System. A system of record processing in which records are entered, maintained, archived, and retrieved electronically. The term “computer-based recordkeeping system” is synonymous with “electronic recordkeeping system.”

1.8.3 Data Backup. Use of one of several recognized methods of providing a secondary means for archiving records, separately from the original or primary. The backup can be used to reconstruct the format and content of electronically stored records in case of loss, failure, or damage to the primary recordkeeping system.

1.8.4 Data Verification. A process of ensuring accuracy of data records by systematically or randomly comparing electronic records with manual data entry documents.

1.8.5 Digital Electronic Signature. A type of electronic signature that uses cryptography to verify the source of digital data is authentic and ensures data integrity has not been compromised.

1.8.6 Electronic Manuals. Certificate holder manuals that may be electronically signed, stored, and retrieved by a computer system via the internet/intranet, or via other various forms of electronic media.

1.8.7 Electronic Record. A contract or other record (including operations specifications) created, generated, sent, communicated, received, or stored by electronic means.

1.8.8 Electronic Recordkeeping System. A system of record processing in which records are entered, signed, stored, and retrieved electronically. The term “electronic recordkeeping system” is synonymous with “computer-based recordkeeping system.”

1.8.9 Electronic Signature. Functionally equivalent to a handwritten signature. The term “electronic signature” means an electronic sound, symbol, or process attached to, or logically associated with, a contract or other record and executed or adopted by an individual with the intent to sign the record.

1.8.10 Operations Specifications (OpSpecs). Documents created and issued by the FAA through the Web-based Operations Safety System (WebOPSS) are collectively referred to as “authorizing documents.” For the purposes of this AC, the use of the term “OpSpec” hereafter refers to one or more of the following WebOPSS authorization documents:

1.8.10.1 Management Specifications (MSpecs). Issued to program managers who conduct fractional ownership operations under 14 CFR part 91K.

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1.8.10.2 Operations Specifications (OpSpecs). Issued to certificate holders operating under 14 CFR part 121, 125, 129, 135, 137, 145, or 147.

1.8.10.3 Letters of Authorization (LOA). Issued to 14 CFR part 91 operators;

certificate holders operating under 14 CFR parts 133, 137, and 141; and 14 CFR part 125 LODA holders.

1.8.10.4 Training Specifications (TSpecs). Issued to 14 CFR part 142 training center certificate holders.

1.8.11 Password. An identification code or device required to access stored material, intended to prevent information from being viewed, edited, or printed by unauthorized persons.

1.8.12 Private Key. A cryptographic key that is used with an asymmetric (public key) cryptographic algorithm. For digital electronic signatures, the private key is uniquely associated with the owner and is not made public. The private key is used to create a digital electronic signature that may be verified using the corresponding public key.

1.8.13 Public Key. A cryptographic key that is used with an asymmetric cryptographic algorithm and is associated with a private key. The public key is linked to an owner and may be made public. For digital electronic signatures, the public key is used to verify a digital electronic signature that was generated using the corresponding private key.

1.8.14 Signature. A mark or sign made by an individual to signify knowledge, approval, acceptance, or obligation, and to authenticate a record entry. A signature should be traceable to the individual making the entry, and it should be handwritten or part of an electronic signature system.

1.9 Approval, Acceptance, and Authorization. There are many 14 CFR part regulations that address electronic signatures, records/recordkeeping, and manuals. There are varying requirements between the many 14 CFR parts for approval, acceptance, and authorization.

1.9.1 FAA Approval Required. FAA approval is required to use the following electronic manual and recordkeeping systems:

1.9.1.1 Electronic MEL. Title 14 CFR §§ 91.1115(a)(2), 121.628(a)(2),

125.201(a)(2), and 135.179(a)(2) certificate holders who conduct operations under 14 CFR part 91K, 121, 125, or 135 must provide flightcrews with direct access to the MEL through printed or other means approved by the Administrator.

1.9.1.2 Title 14 CFR Part 121 Crewmember and Dispatcher Records. Title 14 CFR § 121.683(c) allows a certificate holder to use a computerized recordkeeping system, approved by the Administrator, to maintain crewmember and dispatcher records required by 14 CFR part 121.

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1.9.1.3 Title 14 CFR Part 125 Crewmember Records. Title 14 CFR § 125.401 allows a certificate holder conducting 14 CFR part 125 operations to use a computerized recordkeeping system that is approved by the Administrator to record and maintain crewmember records required by 14 CFR part 125.

1.9.2 FAA Acceptance Required. With the exception of the items that require FAA approval (see paragraph 1.9.1 above), FAA acceptance is required for certificate holders to use electronic signatures, electronic recordkeeping systems, and electronic manual systems to satisfy the requirements of 14 CFR parts 91K, 121, 125, 133, 135, and 145. FAA acceptance is also required for certificate holders who use electronic records, and the electronic signatures associated with those records, to satisfy the requirements of 14 CFR parts 141, 142, and 147.

1.9.3 Authorization in Operations Specification (OpSpec) A025 is Required. The FAA will authorize the use of electronic signatures, electronic recordkeeping systems, and electronic manual systems via OpSpec A025, Electronic Signatures, Electronic Recordkeeping Systems, and Electronic Manual Systems. The OpSpec A025 template name varies by regulatory part. OpSpec A025 authorization is required for 14 CFR parts 91K, 121, 125, 133, 135, 141, 142, 145, and 147. It is important to note that the FAA does not require a certificate holder to use electronic signatures, electronic recordkeeping systems, or electronic manual systems. The use of these electronic systems is optional. However, if a certificate holder elects to exercise this option, that authorization is issued via A025. FAA guidance on the issuance of OpSpec A025 is in FAA Order 8900.1, Volume 3, Chapter 18, Section 3, Part A Operations Specifications— General.

1.9.4 The FAA Will Use OpSpec A025 as the Method to Convey Approval, Acceptance, and Authorization. The FAA will use OpSpec A025 as the method to convey FAA approval or acceptance for those items that require specific FAA approval or acceptance to be maintained, accessed, furnished, or distributed electronically. The signature on the OpSpec by the FAA principal inspector (PI) or other aviation safety inspector (ASI) with OpSpec signature authority indicates the FAA’s approval or acceptance of the item (depending on the requirement). When the FAA issues OpSpec A025 in WebOPSS, the certificate holder is authorized to use the electronic items listed as of the effective date of the active OpSpec. This date also signifies the effective date of FAA approval or acceptance.

1.9.5 There is No Requirement for Formal Approval, Acceptance, or Authorization for 14 CFR Part 61, 63, 65, 91 (excluding 91K), 129, or 137. The use of an electronic signature, electronic recordkeeping system, or electronic manual system under 14 CFR part 61, 63, 65, 91 (excluding 91K), 129, or 137 does not require formal FAA approval, acceptance, or authorization. OpSpec/MSpec/TSpec/LOA A025 does not apply to operations under these parts. However, the FAA recommends that all certificate holders follow the guidelines for electronic signatures, records, and manuals as set forth in the AC, regardless of whether or not approval, acceptance, or authorization is required. If a required signature, record, or manual provided in an electronic format or application does not contain the key elements or does not follow the guidelines set forth in this AC, the

1-7 FAA may question its validity. If the FAA determines that an electronic signature, record, or manual is missing key elements, does not follow the guidelines, or is otherwise unacceptable, the FAA office with oversight responsibility will notify the certificate holder in writing. Upon receiving notification, it is incumbent upon the certificate holder to make the appropriate corrections.

1.9.6 Certificate Holders Who Have Authority in OpSpec A061 to Use an Electronic Flight Bag (EFB) Program. OpSpec A025 is the authorization for the use of electronic signatures, electronic recordkeeping systems, and electronic manual systems. For certificate holders who have authorization to use an EFB program in accordance with OpSpec A061, electronic signatures, electronic recordkeeping systems, and electronic manual functions may co-reside and/or otherwise be displayed on an EFB, provided the certificate holder has authority to use these items in OpSpec A025.

2-1 CHAPTER 2. ELECTRONIC SIGNATURES

2.1 Electronic Signatures. Public Law (PL) 106-229, Electronic Signatures in Global and National Commerce Act (E-Sign Act), defines an electronic signature as an “electronic sound, symbol, or process, attached to or logically associated with a contract or other record and executed or adopted by a person with the intent to sign the record.”

Note: Throughout this AC, the term “electronic signature” refers to either electronic signatures or digital signatures. The specific electronic signature used depends on the end user’s preference and the system application.

2.1.1 Digital Electronic Signatures. Digital electronic signatures are electronic signatures that incorporate encryption and decryption technology. Digital electronic signatures that use this technology are typically the most secure because of the controls that are inherent with the technology itself.

2.1.1.1 Digital Cryptography. Digital electronic signature technology is based on Public Key Infrastructure (PKI) cryptography. PKI is a framework established to issue, maintain, and revoke public key certificates, which are essential for verifying identities and securing communications. Although different, the public and private keys in a key pair are mathematically linked. To ensure the authenticity of a digital electronic signature, PKI incorporates the use of a digital certificate to authenticate the signer’s identity. A digital certificate is issued by a trusted party known as a certificate authority (CA). The CA verifies the identity of the digital certificate holder and issues the digital certificate, assuming responsibility for vouching for the individual’s identity.

2.1.1.1.1 Public Key. A public key is used to verify a digital electronic signature that was generated using the corresponding private key. A more detailed definition of public key is contained in paragraph 1.8.13.

2.1.1.1.2 Private Key. The private key is used to create a digital electronic signature that may be verified using the corresponding public key. A more detailed definition of private key is contained in paragraph 1.8.12.

2.1.1.2 Controls. Digital electronic signatures that use PKI and incorporate digital certificate authentication contain controls that ensure the authenticity of the signature. This technology also ensures the signature is permanently embedded in the document, record, or data in such a way as to render the content unalterable without a new signature.

2.1.2 Key Elements of an Electronic Signature. The following key elements comprise an electronic signature and ensure its validity. In accordance with PL 106-229, an electronic document or record that contains a valid electronic signature or authentication may not be denied legal effect, validity, or enforceability solely because it is in electronic form.

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2.1.2.1 The signature is unique to the signer.

2.1.2.2 There are means to identify and authenticate a particular person as the signer.

2.1.2.3 The signature is under the sole control of the signer.

2.1.2.4 The electronic signature is executed or adopted by a person with the intent to sign.

2.1.2.5 The electronic signature is the result of a deliberate action taken by the signer to affix their signature.

2.1.2.6 The electronic signature prevents the signer from denying that they affixed a signature to a specific record, document, or body of data (nonrepudiation).

2.1.2.7 The electronic signature is permanent and the information to which it is attached is unalterable without a new signature.

2.1.2.8 A document, once signed, cannot be edited.

2.1.3 Electronic Signatures on Regulatory Records. An electronic signature that is affixed to any record required by 14 CFR part 91K, 121, 125, 133, 135, 141, 142, 145, or 147 will require a certificate holder to have an FAA-approved or FAA-accepted (depending on the regulatory requirement) electronic recordkeeping system. These systems are discussed in detail later in this AC.

2.2 Electronic Signature Process. A certificate holder who desires to use electronic signatures should have a definitive process that ensures all of the elements that comprise a valid electronic signature are present. For 14 CFR parts 91K, 121, 125, and 135, an electronic signature process is a requirement of Operations Specification (OpSpec) A025, Electronic Signatures, Electronic Recordkeeping Systems, and Electronic Manual Systems. The following guidelines apply to a certificate holder’s electronic signature process:

2.2.1 Signature Uniqueness. The electronic signature process ensures the uniqueness of the signature, which is difficult to duplicate.

2.2.2 A Means to Convey the Intent to Sign. The electronic signature process prompts the signer before their signature is affixed. The electronic signature block should contain a word or statement of intent that definitively conveys the signer’s intent to affix their signature. Examples of statements that do this include, but are not limited to:

• “Signed by,”

• “Certified by,”

• “Instructor’s signature/certification,”

• “Signature,”