Life-Limited Parts Disposition

FAR 43.10 Life-Limited Parts Disposition

FAR 43.10 explains how to track, mark, segregate, or mutilate life-limited aircraft parts to prevent installation past their replacement limits.

In Plain English

FAR 43.10 governs how mechanics and owners must handle life-limited parts — components with a mandatory replacement limit (cycles, hours, or other measure) set by the type design, Instructions for Continued Airworthiness, or maintenance manual.

When you remove a life-limited part from a type-certificated product, you must control it using a method that deters reinstallation after it reaches its life limit. Acceptable methods include:

  • A record-keeping system (paper or electronic) tracking part number, serial number, and current life status
  • A tag or attached record updated at each removal
  • A non-permanent mark showing life status (per § 45.16)
  • A permanent mark showing life status (per § 45.16)
  • Segregation with records, physically separated from serviceable parts
  • Mutilation that renders the part beyond repair
  • Any other FAA-approved method

If a part is only temporarily removed and reinstalled on the same product for maintenance — and the product accumulates no time in service while the part is off — no disposition action is required. When you sell or transfer a life-limited part, the supporting tag, mark, or record must go with it, unless it has been mutilated. This rule matters because installing a time-expired component can cause catastrophic in-flight failure.

Regulation Text
14 CFR § 43.10
§ 43.10 Disposition of life-limited aircraft parts. (a)For the purposes of this section the following definitions apply. means any part for which a mandatory replacement limit is specified in the type design, the Instructions for Continued Airworthiness, or the maintenance manual. means the accumulated cycles, hours, or any other mandatory replacement limit of a life-limited part. (b)When a life-limited part is temporarily removed and reinstalled for the purpose of performing maintenance, no disposition under paragraph (c) of this section is required if— (1) The life status of the part has not changed; (2) The removal and reinstallation is performed on the same serial numbered product; and (3) That product does not accumulate time in service while the part is removed. (c)Except as provided in paragraph (b) of this section, after April 15, 2002 each person who removes a life-limited part from a type-certificated product must ensure that the part is controlled using one of the methods in this paragraph. The method must deter the installation of the part after it has reached its life limit. Acceptable methods include: (1)The part may be controlled using a record keeping system that substantiates the part number, serial number, and current life status of the part. Each time the part is removed from a type certificated product, the record must be updated with the current life status. This system may include electronic, paper, or other means of record keeping. (2)A tag or other record may be attached to the part. The tag or record must include the part number, serial number, and current life status of the part. Each time the part is removed from a type certificated product, either a new tag or record must be created, or the existing tag or record must be updated with the current life status. (3)The part may be legibly marked using a non-permanent method showing its current life status. The life status must be updated each time the part is removed from a type certificated product, or if the mark is removed, another method in this section may be used. The mark must be accomplished in accordance with the instructions under § 45.16 of this chapter in order to maintain the integrity of the part. (4)The part may be legibly marked using a permanent method showing its current life status. The life status must be updated each time the part is removed from a type certificated product. Unless the part is permanently removed from use on type certificated products, this permanent mark must be accomplished in accordance with the instructions under § 45.16 of this chapter in order to maintain the integrity of the part. (5)The part may be segregated using methods that deter its installation on a type-certificated product. These methods must include, at least— (i) Maintaining a record of the part number, serial number, and current life status, and (ii) Ensuring the part is physically stored separately from parts that are currently eligible for installation. (6)The part may be mutilated to deter its installation in a type certificated product. The mutilation must render the part beyond repair and incapable of being reworked to appear to be airworthy. (7)Any other method approved or accepted by the FAA. (d)Each person who removes a life-limited part from a type certificated product and later sells or otherwise transfers that part must transfer with the part the mark, tag, or other record used to comply with this section, unless the part is mutilated before it is sold or transferred. [Doc. No. FAA-2000-8017, 67 FR 2110, Jan. 15, 2002, as amended by Amdt. 43-38A, 79 FR 67055, Nov. 12, 2014]
Oral Exam Questions a DPE Might Ask
Q1What is a life-limited part, and where would you find its replacement limit?
Per FAR 43.10, a life-limited part is any part with a mandatory replacement limit specified in the type design, Instructions for Continued Airworthiness, or the maintenance manual, expressed in cycles, hours, or other measure.
Q2Name three acceptable methods of controlling a life-limited part once it has been removed from a type-certificated product.
Under FAR 43.10(c), acceptable methods include keeping a record system showing part number, serial number, and life status; attaching a tag or record; non-permanent or permanent marking per § 45.16; segregation; mutilation; or any FAA-approved method.
Q3If you sell a removed life-limited part to another operator, what must accompany the part?
FAR 43.10(d) requires that the mark, tag, or other record used to track the part's life status be transferred with it, unless the part has been mutilated before sale or transfer.
Practice this with our AI examiner

Examiner Reed adapts to your responses and probes deeper on weak spots — full ACS coverage, not a script.

Studying for a checkride?
Related Sections in Part 43
Master the FARs
Stop reading regs. Start drilling them.

Every cite verified against the live FAR/AIM. Adaptive questions surface your weak areas. Mock checkrides predict your DPE pass rate.

5 questions/day free • No credit card
FAR 43.10 — Disposition of Life-Limited Aircraft Parts