What the guidance says
Advisory Circular 120-78B, dated December 11, 2024, "provides approval, acceptance, and authorization guidelines for electronic signatures, electronic recordkeeping systems, and electronic manual systems." 1
Paragraph 1.9.3 states: "The FAA will authorize the use of electronic signatures, electronic recordkeeping systems, and electronic manual systems via OpSpec A025," and "OpSpec A025 authorization is required for 14 CFR parts 91K, 121, 125, 133, 135, 141, 142, 145, and 147." The same paragraph adds: "The use of these electronic systems is optional." 1 The principal inspector's signature on the OpSpec "indicates the FAA's approval or acceptance of the item (depending on the requirement)." 1
The application is the operator's. A certificate holder applies in writing to its Flight Standards office with a letter of intent naming "the kinds of records along with the name of the electronic system." After a demonstration, the FAA authorizes use "by signing and issuing OpSpec A025." 1 The inspector guidance for the Part 135 template has three columns per recordkeeping system: kind of record, "Name of Electronic System" and the manual containing the system description. Part 135 systems are "FAA-accepted"; approval is reserved for Part 121 and 125 crewmember and dispatcher records. 2
What it does not mean
On our reading, "FAA-compliant" or "built to AC 120-78B" on a vendor's page describes a design target, not an FAA review of the product: the AC has no paragraph on reviewing a product apart from a certificate holder, and calls itself "an acceptable means, but not the only means" whose contents "do not have the force and effect of law." 1 Each certificate holder submits its own application, manual and demonstration; one operator's A025 does not transfer to another using the same product. 12
Part 91 operators outside 91K need no A025: electronic use under Part 91 "does not require formal FAA approval, acceptance, or authorization," though the FAA recommends following the AC and "may question" a record missing key elements. 1 An owner-flown aircraft's electronic logbook is therefore a different case from a charter operator's.
Software revision control "is a requirement of" A025 for Part 135, and the process "includes certificate holder notification to the responsible Flight Standards office whenever software revisions affect" record entry, display, access or data quality. 1 While FAA direct access to the system "is voluntary, providing the records themselves is mandatory." 1 A Part 145 repair station's own electronic records go through A025 as well. 1
How to check it yourself
Ask the vendor which A025 table entries its customers hold and which manual describes the system; ask your principal inspector what that description must contain (Order 8900.1, Volume 3, Chapter 18, Section 3, Change 1021, February 26, 2026); and confirm on the FAA's advisory circular page that 120-78B is still Active. 23
Why it matters for AI answers
The buyer's question contains a false premise, and an engine will answer it with a product list unless a page states the rule plainly. A vendor's compliance page can carry one checkable sentence: designed to AC 120-78B (December 11, 2024); authorization to use it is the operator's, via OpSpec A025; last confirmed current on a stated date, in HTML. That is the sentence a software vendor wants quoted when a Part 135 operator asks which records software the FAA accepts.