Direct Answer — Life-Limited Parts Records
Under 14 CFR §43.10(a), a life-limited part is any part with a mandatory replacement limit specified in the type design, the Instructions for Continued Airworthiness, or the maintenance manual; its life status is the accumulated cycles, hours, or other mandatory measure counted against that limit. The current status of every life-limited part is a permanent record under 14 CFR §91.417(a)(2)(ii) — it is retained and transferred with the aircraft at sale under §91.417(b)(2), unlike ordinary maintenance entries that may be purged after one year or when superseded. When a life-limited part is removed, 14 CFR §43.10(c) requires you to control it by a recordkeeping system, tag, marking, segregation, or mutilation; and 14 CFR §43.10(d) requires that the mark, tag, or record travel with the part if it is later sold or transferred — unless the part is mutilated first. A life-limited part with no traceable life status is, for airworthiness purposes, a part with zero remaining life.
A missing life status record grounds the aircraft — even if the part is nowhere near its limit
The FAA cannot distinguish "the part has life left but the paperwork is lost" from "the part is expired." Under 14 CFR §91.417(a)(2)(ii), the current status of life-limited parts must be retained as part of the aircraft's permanent records. If that status cannot be produced, no A&P or IA can approve the aircraft for return to service, and the only remedies are recovering the documentation or replacing the part.
What a Life-Limited Part Is — and Why "Life Status" Is the Number That Matters
14 CFR §43.10(a) gives two definitions that govern everything downstream. A life-limited part is "any part for which a mandatory replacement limit is specified in the type design, the Instructions for Continued Airworthiness, or the maintenance manual." And life status is "the accumulated cycles, hours, or any other mandatory replacement limit of a life-limited part." The distinction from other maintenance regimes is absolute: an on-condition part stays in service as long as inspection shows it is serviceable, and a hard-time part is overhauled at an interval and returned to service refreshed. A life-limited part has neither escape. When its life status reaches the published limit, it is finished — overhaul cannot extend it, inspection cannot reprieve it, and there is no FSDO discretion to wave it through.
Common life-limited parts and the units their limits are expressed in
Turbine engine disks, spools, and hubs
Cycles (often expressed as engine flight cycles)
Main and tail rotor blades, hubs, and grips (rotorcraft)
Hours and/or cycles per the rotorcraft maintenance manual
Certain landing gear structural components
Cycles (landings) or hours
Specified airframe structural members
Hours or cycles per the type design / ICA
Some appliance components (e.g., certain actuators)
Hours, cycles, or calendar limit per the maintenance manual
The authoritative list of life limits for any given aircraft, engine, or propeller is in its type design, Instructions for Continued Airworthiness, or maintenance manual — not a generic list. Always verify the limit and its unit against the manufacturer document that applies to your serial number.
Because the limit is mandatory and unforgiving, the life status must be tracked by serial number. Life-limited parts are never managed as a fungible pool — two identical part numbers can have wildly different remaining life, and installing the wrong one because the paperwork was ambiguous is the failure mode §43.10 exists to prevent. This is also why the time-in-service requirement in 14 CFR §91.417(a)(2)(i) — "the total time in service of the airframe, each engine, each propeller, and each rotor" — matters here: a part's life status has to be reconcilable against the time in service of the item it is installed on. For the broader picture of which records the aircraft must carry, see the Part 91 aircraft records requirements guide and aircraft weight and balance records.
Primary regulations cited in this section: 14 CFR §43.10 (Disposition of life-limited aircraft parts), 14 CFR §91.417 (Maintenance records).
The Permanent Record — §91.417(a)(2)(ii) and Why It Outlives Everything Else
14 CFR §91.417 divides maintenance records into two retention classes, and the difference is the single most misunderstood point about life-limited parts paperwork. Operators who treat the life status list like an ordinary logbook entry — purging it once it is "superseded" — destroy a record the regulation requires them to keep for the life of the aircraft.
§91.417(a)(1) — the 1-year bucket
Records of maintenance, preventive maintenance, and alterations, and records of the 100-hour, annual, progressive, and other required inspections. These "shall be retained until the work is repeated or superseded by other work or for 1 year after the work is performed."
These are disposable on a rolling basis — a year, or whenever the next equivalent entry supersedes them.
§91.417(a)(2) — the permanent bucket
Total time in service (i); current status of life-limited parts (ii); time since last overhaul of items on a time basis (iii); current inspection status (iv); current AD status (v); and copies of the FAA Form 337s prescribed by §43.9(d) for each major alteration (vi). Under §91.417(b)(2) these "shall be retained and transferred with the aircraft at the time the aircraft is sold."
Life status lives here. It is permanent and follows the aircraft to every future owner.
What "current status" actually has to contain
The regulation states the requirement as "the current status of life-limited parts" without prescribing a form. The content that satisfies an inspector — and that lets the next maintainer or buyer act on the record — is consistent across the industry:
Part: HP Turbine Disk · P/N 12345-678 · S/N ABCD-9012 · Life limit: 15,000 cycles · Cycles accumulated (life status): 8,742 · Remaining: 6,258 cycles · Installed on Engine S/N ENG-4456 (engine TIS reconciled) · As of [date]
- Part number AND serial number — life-limited parts are tracked individually, never as a generic pool
- The mandatory life limit and the unit it is expressed in (cycles, hours, or other per the type design/ICA/maintenance manual)
- Accumulated life status to date — the running count against the limit
- Remaining life — derived, but stated so the next maintainer does not have to recompute it
- The serialized item it is installed on, reconciled against §91.417(a)(2)(i) total time in service
A status list missing the serial number, the limit, or the accumulated count cannot establish remaining life
And an inability to establish remaining life is treated the same as an expired part. The whole purpose of §91.417(a)(2)(ii) is to let an inspector confirm, for every installed life-limited part, that its life status has not reached its mandatory limit. A vague entry defeats that — even when the part is mechanically fine.
The life status record sits inside the same permanent set as AD status and inspection status, so it is naturally maintained alongside them. For how the other permanent records work, see airworthiness directive compliance records, the §91.409 annual inspection requirements, and the master list in what records a Part 135 operator must keep.
Related Aviation Compliance Guides
Disposition When the Part Comes Off — §43.10(c) Control Methods
14 CFR §43.10(c) governs the moment a life-limited part is removed from a type-certificated product. Whoever removes it must control it using one of the approved methods, so the part's accumulated life cannot be lost and the part cannot be inadvertently reinstalled past its limit. The regulation lists the acceptable methods explicitly — and they range from a recordkeeping entry all the way to physically destroying the part.
Record it in a recordkeeping system
Document the part removal and its life status in a system that maintains the part-by-serial-number record. This is the method that scales — and the one that produces the §91.417(a)(2)(ii) trail an inspector will look for.
Attach a tag or other record to the part
A physical tag or record affixed to the part carrying its life status, so the accumulated cycles/hours travel with the hardware itself.
Mark the part — non-permanently or permanently
Marking the part (either non-permanent or permanent marking, both listed) so its status is visible on the part. Permanent marking is common where the part might otherwise be mistaken for serviceable stock.
Segregate the part
Physically isolating the part from serviceable inventory so it cannot be drawn and reinstalled by mistake — a quarantine for parts pending disposition.
Mutilate the part
Destroying the part so thoroughly it can never be returned to service. This is the disposition method that, uniquely, also releases the obligation to transfer a record with it under §43.10(d) — because there is no part left to misuse.
The regulation also permits "any other method approved or accepted by the FAA" — but the listed methods cover essentially every legitimate workflow. The unifying principle is that a removed life-limited part must never re-enter service as if it were fresh.
The one exception — §43.10(b) temporary removal
14 CFR §43.10(b) carves out the only case where no disposition action is required. All three conditions must be true: (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. The textbook example is pulling a life-limited component temporarily to gain access to something behind it, then reinstalling the exact same part on the exact same engine or airframe before it flies again. Because nothing about the part's life or installation has changed, the §43.10(c) control methods do not apply. The instant any of those three conditions fails — a different airframe, accumulated time in service, or any change to life status — full disposition control is back in force.
Correct Practice
- Record removal + life status by serial number the moment the part comes off
- Keep the part's life-status record attached to the part (tag/marking) until it is sold or mutilated
- Segregate removed life-limited parts from serviceable stock
- Mutilate parts that will never return to service so they cannot be salvaged into another aircraft
- Reconcile every removal against the §91.417(a)(2)(ii) status list
Common Errors
- Pulling a part and leaving its life status undocumented "to finish later"
- Returning serviceable-looking life-limited parts to general stock with no traceability
- Assuming the §43.10(b) temporary-removal exception applies when the aircraft flew in the interim
- Treating two same-P/N parts as interchangeable without checking each serial number's life status
- Mutilation in practice but no record that the part was scrapped
Part 145 repair stations that remove and install life-limited parts have both the §43.9 entry obligation and the §43.10 disposition-control obligation. See Part 145 repair station recordkeeping and the §43.9 maintenance record entry requirements for the entry-content rules that pair with disposition control.
Transfer & Sale — §43.10(d) and Why the Record Belongs to the Part
14 CFR §43.10(d) is short and absolute: "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." Read carefully, it establishes that the life status record is not the seller's property to retain — it is an attribute of the part itself. Whatever §43.10(c) method documented the part's accumulated life must follow the part to its next owner.
Two clean outcomes — and nothing in between
Sell or transfer the part
The mark, tag, or record documenting its life status goes with it. The buyer now knows exactly how many cycles or hours remain and can make an informed install decision.
Mutilate the part first
Destroy it so it can never return to service. Only then is the obligation to transfer a record released — because there is no part left to install.
What §43.10(d) forecloses is the dangerous middle: a used life-limited part changing hands with no traceable life status. That part is, in practice, unusable — a responsible installer cannot put it on an aircraft without proving its remaining life, and a part with no proof has, for airworthiness purposes, zero.
At aircraft sale — the §91.417(b)(2) chain-of-custody
When an entire aircraft changes hands, the installed life-limited parts' current status moves under a separate but reinforcing rule. 14 CFR §91.417(b)(2) requires the §91.417(a)(2) records — including the life-limited parts status under (a)(2)(ii) — to "be retained and transferred with the aircraft at the time the aircraft is sold." So a buyer should receive a complete, current life status list for every installed life-limited part, reconciled against the aircraft and engine time in service. A pre-purchase inspection by an IA should specifically verify that the life status of every life-limited part is documented and current — not merely that the logbooks exist. The risk concentrates in turbine and rotorcraft fleets, where the most expensive parts on the aircraft are life-limited and a gap in the status chain can force a six-figure replacement triggered purely by missing documentation.
Used life-limited parts and aircraft purchases carry the same trap
A part bought without its §43.10(d) record, or an aircraft accepted without a complete §91.417(a)(2)(ii) status list, transfers an undocumented life-status gap to the new owner. The FAA treats "records not available" as "remaining life not established" — and the new owner inherits the burden of re-establishing it or replacing the part.
For how life-limited parts tracking fits a continuous airworthiness maintenance program, and the buyer-side records due-diligence pattern, see Part 135 maintenance recordkeeping & CAMP requirements, Part 91K fractional ownership compliance records, and the equipment-status discipline behind RVSM altimeter and transponder inspection records.
FileFlo as the Life-Limited Parts Proof Layer
Life-limited parts tracking has two halves. One half is the running engineering calculation of cycles and hours against each limit — that belongs to your maintenance tracking system (CAMP, Veryon, your engine-trend program, your A&P's work orders). The other half is the documentary proof that the status is current, that disposition was controlled, and that the record traveled with the part or the aircraft. That second half is where records actually fail an audit — and it is the half FileFlo addresses.
A read-only proof layer that sits alongside your tracking stack
FileFlo is a compliance document intelligence platform. It does not compute life limits, run your maintenance program, or replace CAMP or Veryon. What it does is classify, index, and surface the documents that prove life-limited parts compliance when an inspector, an insurer, or a buyer asks.
- Classifies uploaded life-status lists, serialized part tags, FAA Form 8130-3 release tags, and disposition records against the governing 14 CFR reference (§43.10, §91.417(a)(2)(ii))
- Indexes life-limited parts documentation by part number and serial number so the right record surfaces against the right hardware
- Tracks expiration-style alerts on the documents you upload — flagging when a recorded remaining-life figure is approaching its limit, at 90/60/30-day style thresholds you configure
- Keeps the §43.10(d) transfer record linked to its part so a sale or transfer never loses the life-status trail
- Retains the life-limited parts status as a permanent record with version history, and assembles an inspector-format binder organized for §91.417 review on demand
FileFlo classifies 600+ aviation document types and manages records across Part 91, Part 135, and Part 145 operations in a single platform. Pricing: Starter $89/mo, Professional $299/mo. 5-day free trial, no credit card required. FileFlo does not provide or run a safety management system (SMS), dispatch/flight operations system, or maintenance-tracking program — it keeps the documents that prove compliance audit-ready.
For operators preparing for an FAA review, the records-readiness discipline is the same one covered in how to prepare for a Part 135 FAA surveillance audit, and the inspector-binder pattern in the Part 145 audit binder guide.
Who Owns the Obligation — Part 91, Part 135, and Part 145
The §43.10 disposition rules bind anyone who removes a life-limited part from a type-certificated product — Part 43 governs the act of maintenance regardless of operating certificate. The §91.417(a)(2)(ii) retention duty falls on the aircraft owner or operator. What changes across certificate types is the accountability apparatus, not the recordkeeping standard.
Who is responsible
Owner/operator (§91.403)
The owner personally ensures every installed life-limited part's life status is tracked and current. No required maintenance department — most vulnerable to status-list gaps and lost transfer records on used parts.
Who is responsible
Director of Maintenance via CAMP / OpSpecs
The maintenance program must account for life-limited parts across the fleet by serial number. The DOM carries the accountability under Operations Specifications; the Principal Maintenance Inspector reviews.
Who is responsible
Repair station performing the removal/install
Must produce a correct §43.9 entry and apply §43.10 disposition control to any life-limited part it removes — but the operator retains the §91.417 retention duty for the installed status.
Rotorcraft operators carry the heaviest life-limited parts load because so many rotor components are hard-limited — see Part 135 helicopter air ambulance (HEMS) records. And the FAA's personnel-side recordkeeping ramp-up under the Pilot Records Database is a useful parallel for how seriously the agency treats status documentation — see the Pilot Records Database (Part 111) requirements.
For the operational-control and management-personnel context around who in a Part 135 organization is accountable for these records, see what operational control means in Part 135 and the required management personnel qualifications. The 2024 SMS rule — which applies to all Part 135 certificate holders with a single May 28, 2027 compliance deadline — adds a safety-data layer on top; see the Part 135 SMS 2027 deadline guide.
Frequently Asked Questions
What is a life-limited part under 14 CFR §43.10?
14 CFR §43.10(a) defines a life-limited part as "any part for which a mandatory replacement limit is specified in the type design, the Instructions for Continued Airworthiness, or the maintenance manual." In plain terms, it is a part the manufacturer and the FAA have determined cannot safely be operated past a fixed limit expressed in flight hours, cycles, or another mandatory measure — turbine engine disks, rotor blades and hubs, certain landing gear components, and some structural members are common examples. The same section defines "life status" as "the accumulated cycles, hours, or any other mandatory replacement limit of a life-limited part." The life status is the running count against that mandatory limit, and it is the single number that determines whether the part may legally remain in service. Unlike a part on a soft-time or on-condition program, a life-limited part has a hard ceiling: when the life status reaches the published limit, the part must come off — there is no inspection, overhaul, or repair that resets the clock.
How long must life-limited parts records be retained — and does §91.417 treat them differently from ordinary maintenance records?
Yes — life-limited parts status is a permanent record, not a one-year record. 14 CFR §91.417 splits maintenance records into two retention buckets. The §91.417(a)(1) records (the entries describing maintenance, preventive maintenance, alterations, and 100-hour/annual/progressive inspections) are retained only "until the work is repeated or superseded by other work or for 1 year after the work is performed." The §91.417(a)(2) records are different: under §91.417(b)(2) they "shall be retained and transferred with the aircraft at the time the aircraft is sold." The current status of life-limited parts sits in this second bucket — specifically §91.417(a)(2)(ii), "the current status of life-limited parts of each airframe, engine, propeller, rotor, and appliance." That means the life-limited parts status record follows the aircraft for its entire operational life and must be handed to the buyer on every sale. Discarding it after a year — the way an operator might purge a routine logbook entry once superseded — is a recordkeeping violation, and a missing life status record can ground the aircraft until the part's remaining life can be re-established from documentation.
What does §91.417(a)(2)(ii) require me to actually record about a life-limited part?
14 CFR §91.417(a)(2)(ii) requires the records to contain "the current status of life-limited parts of each airframe, engine, propeller, rotor, and appliance." The regulation states the requirement at a high level — "current status" — and does not prescribe a form, so the practical content that satisfies an inspector is: the part name and part number; the serial number (life-limited parts are tracked individually by serial number, never as a fungible pool); the mandatory life limit and the unit it is expressed in (hours, cycles, or other); the accumulated life status to date; and the resulting remaining life. Because §91.417(a)(2)(i) separately requires the total time in service of the airframe, each engine, each propeller, and each rotor, the life status of a part installed on one of those items must be reconcilable against that time in service. An inspector reading the records must be able to determine, for every life-limited part installed, that its life status has not reached its mandatory limit. A status list that omits the serial number, the limit, or the accumulated count cannot establish that — and an inability to establish remaining life is treated the same as an expired part.
What are the §43.10 disposition rules when a life-limited part is removed from an aircraft?
14 CFR §43.10(c) requires that each person who removes a life-limited part from a type-certificated product control that part using one of the approved methods so it cannot be inadvertently reinstalled beyond its limit. The listed methods are: recording the part's removal and life status in a recordkeeping system; attaching a tag or other record to the part; non-permanently marking the part; permanently marking the part; segregating the part; mutilating the part; or any other FAA-approved method. There is one narrow exception in §43.10(b): if a part is removed and reinstalled on the same serial-numbered product, its life status has not changed, and the product accumulates no time in service while the part is off, no disposition action is required — this covers, for example, removing a component temporarily to access something else and putting the exact same part back. The point of §43.10(c) is traceability: once a life-limited part leaves an aircraft, its accumulated life must travel with it so it is never installed somewhere else as if it were fresh.
When I sell or transfer a removed life-limited part, what record must go with it under §43.10(d)?
14 CFR §43.10(d) states: "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." In other words, the life status record is not yours to keep — it belongs to the part. Whatever method you used under §43.10(c) to document the part's accumulated cycles or hours (the tag, the marking, or the recordkeeping entry) must accompany the part to its next owner so they know exactly how much life it has left. The only way to legitimately separate the record from the part is to mutilate the part first — destroying it so thoroughly that it can never be returned to service — which is itself one of the §43.10(c) disposition methods. A used life-limited part offered for sale with no traceable life status is, in practice, scrap: a responsible installer cannot put it on an aircraft without being able to prove its remaining life.
Why is a life-limited part with missing paperwork treated as if it has zero remaining life?
Because the FAA cannot distinguish "the part has plenty of life left but the paperwork is lost" from "the part is at or past its limit." A life-limited part's authority to remain in service comes entirely from documentation that proves its life status is below the mandatory limit. If the §91.417(a)(2)(ii) status record cannot be produced — or a used part arrives without the §43.10(d) traceability that must accompany it — there is no evidentiary basis to conclude the part is within limits. An A&P or IA cannot lawfully approve the aircraft for return to service, and an inspector reviewing the records during a ramp check or surveillance audit cannot establish airworthiness. The practical consequence is severe: the only ways to restore the aircraft are to locate the missing documentation, or to replace the part with one whose life status is fully traceable. For an engine disk or rotor component, that can mean a six-figure replacement triggered purely by a recordkeeping gap, not by any mechanical condition.
Does the life-limited parts recordkeeping obligation apply to Part 91, Part 135, and Part 145 alike?
The §43.10 disposition rules apply to anyone — at any operation or repair facility — who removes a life-limited part from a type-certificated product, because §43.10 is part of the maintenance rules in 14 CFR Part 43 that govern the act of maintenance regardless of the operator's certificate. The §91.417(a)(2)(ii) retention obligation applies to the owner or operator of the aircraft. What changes across certificate types is the accountability layer. A Part 91 owner is personally responsible under §91.403 for ensuring the life status of every installed part is tracked and current. A Part 135 operator's maintenance program — typically a CAMP, with the Director of Maintenance accountable under the Operations Specifications — must account for life-limited parts across the fleet by serial number. A Part 145 repair station that removes or installs a life-limited part must produce a correct §43.9 maintenance entry and comply with §43.10 disposition control, but the operator still owns the §91.417 retention duty. The recordkeeping standard itself does not relax for smaller operators — only the size of the apparatus tracking it changes.
Don't let a missing tag turn a good part into scrap
FileFlo classifies every uploaded life-status list, serialized part tag, and 8130-3 release against its governing 14 CFR reference, links the §43.10(d) transfer record to its part, surfaces remaining-life alerts on the documents you store, and assembles an inspector-format §91.417 binder on demand. Starter plan $89/mo. Professional $299/mo. 5-day free trial — no credit card required.
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Written by Chad Griffith, Founder, FileFlo — compliance document intelligence. Reviewed June 9, 2026. FileFlo is a compliance document intelligence platform — not legal counsel or an A&P. Verify every life limit, life-status calculation, and disposition action with a certificated A&P, IA, or your FSDO.