Guide · 2 min read
Back-to-birth records and LLP traceability at aircraft redelivery
Life-limited parts can only remain in service when their history is documented. At redelivery, lessors usually expect that history to be complete, which makes the records review one of the longest tasks in a lease return.
What back-to-birth means
A life-limited part (LLP) has a certified life, expressed for example in cycles, after which it must be removed from service. Back-to-birth traceability is the documented history of the part from its manufacture to its current installation: each operator, installation, removal and shop visit, and the life consumed along the way.
Engine LLPs such as disks and shafts, and landing gear components, are the usual focus of this review.
Why it matters at redelivery
Without complete traceability, a part's remaining life cannot be demonstrated. Depending on the lease, the lessor may refuse the part, require its replacement or seek compensation, and the next operator and its authority will ask the same questions. Gaps found late are a common source of redelivery delays.
What a complete LLP package usually contains
- A status sheet per engine or landing gear with part numbers, serial numbers, life limits, life used and life remaining.
- The chain of documents that supports the life accumulated during each operator's period.
- Shop visit records and release certificates for each installation.
- Non-incident statements, where the lease or the next operator requires them.
- Records of any repair or approved deviation affecting the part.
Organising the records review
- Compare what the lease requires with what the records library actually holds.
- Review the highest-value items first: engine LLPs, landing gear and major components.
- Log every gap as a finding with an owner, a due date and the evidence that will close it.
- Agree early with the lessor how each gap will be resolved: additional documents, replacement or commercial settlement.
Working with previous operators and repair shops
Gaps often concern periods before the current lease: earlier operators, shop visits performed by other repair stations or parts acquired from third parties. Requests for missing documents can take weeks to answer, so raise them as soon as a gap is found and record each request and reply against the corresponding finding.