Who signs what: owners, mechanics, and your records

Federal law gives aircraft owners and mechanics different, complementary roles — and TachMinder is built around that split rather than papering over it. Understanding who is responsible for what makes the app's behavior make sense: why the owner's account owns the record, why mechanic submissions arrive as proposals, and why certain records carry a certificate number and others don't.

The owner: airworthiness and the records

The owner/operator is primarily responsible for maintaining the aircraft in an airworthy condition — that's 14 CFR §91.403 — and is the custodian of the maintenance records under §91.417. Not the mechanic, not the shop, not the app: the owner keeps the records, and the records follow the aircraft.

TachMinder mirrors this directly. The owner's account owns the aircraft record, and everything a mechanic submits through the app lands as a proposal that the owner reviews and accepts. The mechanic contributes; the owner curates. That's not a workflow preference — it's the regulatory structure, expressed in software. (See Working with your mechanic for the day-to-day flow.)

What owners can sign for themselves

Owners aren't limited to record-keeping. Under §43.3(g), a pilot who owns or operates the aircraft may perform preventive maintenance (as long as the aircraft isn't operated under part 121, 129, or 135), and under §43.7(f) a pilot holding at least a private pilot certificate may approve the aircraft for return to service after that work — signing the entry themselves. What counts as preventive maintenance isn't a judgment call: it's a defined list in Part 43 Appendix A, covering items like changing landing-gear tires, replacing or cleaning spark plugs, and cleaning or replacing oil filters. Work on the list, done and signed by the owner, is a legitimate maintenance record entry. Work off the list needs a mechanic.

The mechanic: the signature that returns the aircraft to service

Here's the part that surprises people: there is no separate "return to service certificate." The mechanic's maintenance record entry under §43.9 — carrying their signature, their certificate number, and the kind of certificate they hold, per §43.9(a)(4) — is the approval for return to service for the work performed. The logbook entry isn't documentation of the approval; it is the approval. That's why those three elements — signature, certificate number, kind of certificate — matter so much, and why TachMinder treats records that carry them differently from records that don't.

Annuals are a special case

Annual inspections are signed by an IA — a mechanic holding Inspection Authorization — or by an appropriately rated repair station. A plain A&P certificate, without Inspection Authorization, is not sufficient to sign off an annual. If you're looking at an annual entry, the signer's kind of certificate is part of what makes the entry valid. (Inspection entries like annuals are also made under their own recordkeeping rule, §43.11, rather than §43.9.)

How this plays out in TachMinder

• Mechanics record their certificate details. When a mechanic submits completed work, they record the kind of certificate they hold — A&P, IA, or repair station — along with their certificate number. See Submitting work for owner approval for the provider-side flow.
• The owner accepts the record. Submitted work becomes part of the aircraft record when the owner accepts it, consistent with the owner's role as records custodian under §91.417.
• TachMinder stores what was signed — nothing more. The app is a record-keeping tool. It never itself certifies airworthiness or approves return to service; only the certificated person's signature does that. The app records that signature faithfully, which is a different thing entirely.
• Messages are not signoffs. Conversations in the app are attributed to their author, but a chat message saying "you're all set" is not a maintenance record entry and carries no return-to-service weight. The record is the record; the conversation is just the conversation.

Why the asymmetry is a feature

A tool that let anyone write anything into an aircraft record would be easier to build and worthless to trust. The value of a maintenance record comes precisely from who was allowed to write each part of it: the owner keeping custody, the mechanic's certificate standing behind the work. TachMinder keeps those lines where federal law drew them.