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  2. Sustainment Key Performance Parameter (KPP) & Supporting Metrics

Sustainment Key Performance Parameter (KPP) & Supporting Metrics


Alternate Definition

The Sustainment KPP is derived from system availability requirements to support the required capability, assumptions for its design and operational use as specified in the Concept of Operations (CONOPS) and/or Operational Mode Summary/Mission Profile (OMS/MP) tradeoffs between reliability, maintenance concepts, lifecycle cost (LCC), and the planned sustainment strategy. In order for the Progam Manager (PM) to develop a complete system to provide warfighting capability, sustainment attributes must be established and performance of the entire system measured against those metrics. The Sustainment KPP is comprised of several mandatory components: Materiel Availability (Am)and Operational Availability (Ao), and three mandatory attributes (either Key System Attributes (KSA) or Additional Performance Attributes (APA)): Reliability (R), Maintainability (M), and Operating and Support (O&S) cost.

General Information


The JCIDS Manual defines a KPP as performance attributes of a system considered critical or essential to the development of an effective military capability. Failure of a system to meet a validated KPP threshold value triggers a review by the validation authority and evaluation of operational risk and/or military utility of the associated system(s) if KPP threshold values are not met. The review may result in validation of an updated KPP threshold value, modification of production increments, or recommendation for program cancellation. The JCIDS Manual continues describing KSAs as performance attributes of a system considered important to achieving a balanced solution/approach to a system, but not critical enough to be designated a KPP.

Sustainment outcome metrics are breifed to the Milestone Decision Authority (MDA) via the sustainment quad chart as part of the Defense Acquisition Board (DAB) meetings; the title of the meeting granting programs permission to transition from one acquisition phase to the next. The four quadrants of the quad chart are product support strategy (PSS), sustainment schedule, metrics data and operating and support (O&S) cost data. Before signing the Acquisition Decision Memorandum (ADM) granting programs the ability to transition to the next acquisition phase, the MDA needs to know the system is sutainable and the life cycle outcome metrics are the prime indicators of that potential. 

The Sustainment KPP is intended to ensure an adequate quantity of the capability solution will be ready for tasking to support operational missions. The components are defined by the JCIDS Manual as follows:

Materiel Availability (Am)

Am is the measure of the percentage of the total inventory of a system operationally capable, based on materiel condition, of performing an assigned mission. This can be expressed mathematically as the number of operationally available end items/total population. The total system population includes all operational systems necessary to support the operational context of the Capability Development Document (CDD), to include operational systems for training (vice mock-ups, partial systems, simulators), systems for attrition reserve and prepositioning, and systems temporarily in a non-operational materiel condition, such as planned depot maintenance. Am covers the timeframe from placement into operational service through the planned end of service life. Am should take into account all calendar time that a system is in the inventory, including “out-of-reporting” status. For single or small-quantity systems, Am can represent available time (i.e., up time, when the system is in operational status) as a percentage of total calendar time.

Operational Availability (Ao)

Ao is the measure of the percentage of time that a system or group of systems within a unit are operationally capable of performing an assigned mission and can be expressed as (uptime/ (uptime + downtime)). Ao is usually specified for a given scenario or type of unit, e.g., combat group wartime scenario, peacetime training unit, etc. It is normally based on a steady-state situation, usually expressed in terms of annual usage. Determining the optimum value for Ao requires a comprehensive analysis of the system and its planned CONOPS and/or OMS/MP, including the planned operating environment, operating tempo, reliability and maintenance concepts, and supply chain solutions.

Reliability (R)

R is a measure of the probability that the system will perform without failure over a specific interval, under specified conditions. R shall be sufficient to support the warfighting capability requirements, within expected operating environments. Considerations of R must support both availability metrics and be reflected in the O&S cost attribute.

Maintainability (M)

M is the measure of the ability of the system to be brought back to a readiness status and state of normal function.

O&S Cost

Measuring O&S cost provides balance to the sustainment solution by ensuring that the total O&S costs across the projected lifecycle associated with Am, Ao and R are considered in making decisions. The O&S cost attribute is to be computed using base year dollars and covers the planned O&S timeframe, consistent with the timeframe and system population identified in the sustainment performance attribute. The O&S cost KSA/APA objective values are to be calculated in base year dollars as ten percent less than the threshold value.


Documenting the Sustainment KPP

A Reliability, Availability, Maintainability and Cost (RAM-C) Rationale Report will document the quantitative basis for the elements of the Sustainment KPP as well as the technical feasibility tradeoffs and rationale made with respect to system performance, program costs and schedule.

The standard format for briefing the Sustainment KPP is the Sustainment Quad Chart. This chart, typically provided in PowerPoint, as the name suggests, has four quadrants. The top left quadrant dicusses the system's product support strategy and key issues impacting it. The bottom left quadrant will be the sustainment schedule; a timeline of significant sustainment events. The entire right side, both quadrants are devoted to supporting the Sustainment KPP. The top right lists the metrics data of the five, possibly six if mean down time is included, of the Sustainment KPP components. The bottom right quadrant is devoted entirely to O&S data.

The Sustainment KPP is briefed to the Milestone Decision Authority (MDA) at a meeting termed the Defense Acquisition Board (DAB) which determines if a program is able to proceed from one acquisition phase to the next. If, among other required KPPs, the Sustainment KPP is on track, the MDA signs the Acquisition Decision Memorandum (ADM) granting that authority.

The reason for two methods of measuring availability (Materiel and Operational), is a question that often arises. Materiel availability is a very broad measurement of the total number of available systems the combatant commander has at their disposal to prosecute any given mission. Similarly, when Congress asks about weapon-systems availability they aren't concerned with detailed, hour-by-hour status given by the operational measurement. These high-level entities only want the "big picture" of materiel availability. Unit commanders, on the other hand, need the increased granularity of operational availability to manage their readiness. So, the reason for two measurements of the same thing is, it depends on who's asking the question. Put another way, Materiel Availability (the Number of Operational End Items / Total Population) is the percentage of the total inventory of a system operationally capable, based on materiel condition, of performing an assigned mission. Operational Availability on the other hand (Uptime/(Uptime + Downtime)) is the percentage of time that a system or group of systems within a unit are operationally capable of performing an assigned mission.

These metrics are used as triggers to conduct further investigation and analysis into drivers of those metrics, develop "should cost targets", and develop strategies for improving reliability, availability, & maintainability at reduced cost (including the use of outcome-based performance-based life cycle product support (i.e., Performance Based Logistics, PBL) product support strategies and product support arrangements (PSA). Keep in mind that these four metrics are envisioned to be integrated, and very likely will include sub-tier supporting metrics. The O&S cost KSA, for example, provides balance; sustainment solutions cannot be availability and reliability "at any cost." They also facilitate both product and process development and improvement.

Sustainment metrics are forecasted early in a program's life, beginning a Milestone A with the RAM-C Rationale Report. This report assists combatant commanders, program managers, engineers and life cycle logisticians in designing reliability, availability, and maintainability into the system without losing focus of affordability. These metrics forecasted early drive design initiatives that ultimately determine how that program will be supported.