Maintenance Records, Approvals for Return to Service, and Recordkeeping
The approval chain
No person may approve an aircraft or component for return to service until the work has been performed using the methods, techniques, and practices acceptable to the Administrator (Part 43), and the person who signs the record is the person who approves. Signing is an act of certification, not clerical work.
What the entries must contain
A maintenance entry (Section 43.9) states the work performed, the date of completion, the signer's name, and, if certificated, the certificate number and kind of certificate. An inspection entry (Section 43.11) adds: the type of inspection, the aircraft total time in service, and a statement that the inspection was performed in accordance with Part 43 and Appendix D. A pilot performing preventive maintenance signs with name, date, and certificate number.
Major repairs and major alterations require FAA Form 337 in addition to logbook entries; a copy goes to the FAA (traditionally within 48 hours of return to service) and a copy stays with the aircraft records.
Owner and operator records
Section 91.417 requires records of maintenance, alterations, and required inspections. Retention: one year after the work is performed, or until the work is repeated or superseded. The enduring records - total time in service, current status of applicable ADs (number, revision date, method of compliance, and next recurring action), life-limited part status, and current inspection status - must be retained and transferred with the aircraft on sale (Section 91.419). Section 39.7 separately requires the owner or operator to keep AD status information and make it available on request.
Traps
Time in service belongs in the inspection entry, not the routine maintenance entry. Records transfer with the aircraft; they are not discarded at sale. An AD entry without a method of compliance is incomplete.