References

The public standards and guidance this topic draws on. Every factual claim in the preceding chapters traces to one of these; the worked example's fleet, items, prices and results are illustrative teaching values and belong to no source.

The lineage matters here more than in most topics, because the document practitioners cite by habit was cancelled in the 1990s and replaced twice since.

The active standards

1. SAE AS1390A, Level of Repair Analysis (LORA), 4 April 2023, issued by the SAE Life Cycle Logistics Supportability committee (original issue AS1390, 15 April 2014; adopted for US Department of Defense use 8 October 2014). Process-oriented rather than model-prescriptive: programme strategy, planning, reviews, input data compilation, performing and documenting the evaluation, and using the results, with economic, non-economic and sensitivity evaluations recognised as distinct types.
2. MIL-HDBK-1390, Level of Repair Analysis, US Department of Defense, 29 January 2015 (guidance for AS1390, explicitly non-mandatory).
3. TA-STD-0017, Product Support Analysis, adopted for DoD use on 11 June 2013 as a TechAmerica standard, since transferred to SAE, whose issue was adopted for DoD use on 22 August 2024 (LORA appears as a sub-activity of the evaluation of alternatives and trade-off activity, rather than as a standard of its own).
4. MIL-HDBK-502A, Product Support Analysis, US Department of Defense, 8 March 2013, superseding MIL-HDBK-502 of 30 May 1997 (guidance; its LORA appendix states that it contains no requirements and is not to be referenced in contractual documents. It is also the document that named COMPASS as a freely available LORA tool, at a US Army address that no longer resolves).
5. SAE GEIA-STD-0007, Logistics Product Data (where the data requirements that once sat in MIL-PRF-49506 now live).

The historical documents

6. MIL-STD-1390D, Level of Repair Analysis (LORA), US Department of Defense, 19 January 1993 (cancelled). Establishes general requirements and specific tasks for performing LORA across the life cycle, and is still the most widely cited statement of the decision logic: preempting factors, a non-economic evaluation performed without consideration of costs, an economic evaluation performed regardless, and a recommendation of discard or of repair at one named level.
7. MIL-STD-1390C, Level of Repair (LOR), 8 July 1988 (cancelled; Navy-scoped, and titled differently: the LORA wording arrives at revision D).
8. MIL-PRF-49506, Logistics Management Information, 11 November 1996 (superseded 1390D; itself cancelled by Notice 2 on 31 March 2011, superseded by GEIA-STD-0007).

UK and international practice

9. Def Stan 00-600, Integrated Logistic Support Requirements for MOD Projects (the requirement to conduct supportability analysis, including LORA, on UK defence projects).
10. JSP 886, The Defence Logistics Support Chain Manual, Volume 7 Part 3, Supportability Analysis, version 2.5 of 14 July 2014 (now archived in favour of the Defence Logistics Framework). Places LORA as a sub-task of the evaluation of alternatives and trade-off analysis task, states that the decision is normally based on economic factors unless there are overriding operational requirements, and adopts the US source, maintenance and recoverability coding construct with the code characteristics identified from the LORA.
11. ASD/AIA S3000L, International procedure specification for Logistic Support Analysis (the international LSA process, in which LORA is one of the analyses that consumes maintenance task analysis results). It is revised on its own schedule; the current issue and its date are published at s-series.org, which is also where the specification is downloadable.

Related

12. SAE TA-HB-0009 and the wider product support analysis handbook material, for worked guidance on the analyses that surround LORA.
13. The published operational-research literature on joint level-of-repair and spares optimisation, which formulates the repair-level decision and the stocking decision as one optimisation across indenture levels and echelons rather than as two sequential ones. Practitioner tools generally solve them in sequence, and the difference is a known approximation rather than a controversy.

For the task times and resources every option in this analysis is costed from, see the maintenance task analysis module; for the failure rates behind the demand, the prediction references; for the field data that eventually settles the marginal items, FRACAS.