Can I keep deferring an inoperative item forever?

No. Paragraph (c) says equipment deferred under 91.213(d)(2) has to be dealt with at the next required inspection, so a deferral lasts until the next annual or 100-hour at most.

Who makes the logbook entry, the owner or the mechanic?

The mechanic writes it. The owner's duty under paragraph (b) is to make sure the entry is made before the aircraft flies.

14 CFR Part 91 · Subpart E · Maintenance, Preventive Maintenance, and Alterations

14 CFR 91.405: Maintenance the owner must have done

The owner or operator must have the aircraft inspected as Part 91 requires and have discrepancies repaired between inspections. They must also make sure the mechanic logs every return to service and placards anything left inoperative.

Section last amended December 30, 2016 · Text current as of October 15, 2026 · Also cited as FAR 91.405 · Read it on eCFR

14 CFR 91.405 in plain English

Have the required inspections done, and get discrepancies found between them repaired under Part 43. (a)
Make sure maintenance personnel enter the return to service in the aircraft records. (b)
Equipment you were allowed to leave inoperative under 91.213(d)(2) must be repaired, replaced, removed or inspected at the next required inspection. (c)
When a list of discrepancies includes inoperative equipment, make sure it carries the placard 43.11 requires. (d)

Common questions

Can I keep deferring an inoperative item forever?: No. Paragraph (c) says equipment deferred under 91.213(d)(2) has to be dealt with at the next required inspection, so a deferral lasts until the next annual or 100-hour at most.
Who makes the logbook entry, the owner or the mechanic?: The mechanic writes it. The owner's duty under paragraph (b) is to make sure the entry is made before the aircraft flies.

Official text of 14 CFR 91.405

§ 91.405 Maintenance required. Verbatim from the eCFR, current as of October 15, 2026.

Each owner or operator of an aircraft:

(a)Shall have that aircraft inspected as prescribed in subpart E of this part and shall between required inspections, except as provided in paragraph (c) of this section, have discrepancies repaired as prescribed in part 43 of this chapter;

(b)Shall ensure that maintenance personnel make appropriate entries in the aircraft maintenance records indicating the aircraft has been approved for return to service;

(c)Shall have any inoperative instrument or item of equipment, permitted to be inoperative by § 91.213(d)(2) of this part, repaired, replaced, removed, or inspected at the next required inspection; and

(d)When listed discrepancies include inoperative instruments or equipment, shall ensure that a placard has been installed as required by § 43.11 of this chapter.

AerScheduler keeps each aircraft's inspections and squawks in one place, and a grounded aircraft comes off the schedule. See how

14 CFR 91.405 in plain English

Common questions

Official text of 14 CFR 91.405

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