Primary Functional Area : Life Cycle Logistics
Key System Attributes (KSAs) are defined as, “System attributes considered essential for achieving a balanced approach to developing an effective military capability, but not selected as Key Performance Parameters (KPPs). KSAs provide decision makers with an additional level of capability prioritization below the KPP but with senior sponsor leadership control (generally four star, defense agency commander, or principal staff assistant).” (Source: DAU Glossary of Defense Acquisition Acronyms and Terms)
Reliability is a measure of the probability that the system will perform without failure over a specific interval, under specified conditions. Reliability shall be sufficient to support the warfighting capability requirements, within expected operating environments (Source: JCIDS Manual).
This definition stresses the elements of probability, satisfactory performance, time, and specified operating conditions. These four elements are critical, since each plays a key role in determining product or system reliability.
The MANUAL FOR THE OPERATION OF THE JOINT CAPABILITIES INTEGRATION AND DEVELOPMENT SYSTEM (JCIDS Manual) states that while the Sustainment Key Performance Parameter (KPP), Availability, is intended to ensure an adequate quantity of the capability solution will be ready for tasking to support operational missions, the supporting Reliability KSA and O&S Cost KSA, ensure that the Sustainment KPP is achievable and affordable in its operational environment. Together, the KPP and supporting KSAs ensure early sustainment planning, enabling the requirements and acquisition communities to provide a capability solution with optimal availability and reliability to the warfighter at an affordable life cycle cost.
The fact that the Availability (or Sustainment) Key Performance Parameter (KPP) and the two supporting KSAs (Reliability and O&S Cost) are mandatory is not coincidental. Achieving high Reliability has a cost, as does achieving superior Maintainability and a high Availability. These Sustainment metrics taken together bound the trade space for “designing in” supportability and planning affordable life-cycle product support.
The JCIDS manual identifies Reliability as a measure of the probability that the system will perform without failure over a specific interval, under specified conditions. Highlighted is the point that Reliability shall be sufficient to support the warfighting capability requirements, within expected operating environments.
More than one reliability metric may be specified, as KSAs for a system as appropriate.
In all cases, the sponsor should define specific criteria which constitute failure.
Table 1 provides a guide for developing the appropriate sustainment metrics for different categories of systems as an aid for the Sustainment KPP.
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Distinguishing Characteristics |
Materiel Availability |
Operational Availability |
| Ship Platforms |
Naval vessels with multiple missions and multiple large or complex systems. Planned down time. |
The availability of the entire population of systems for tasking when a ship is not in a planned maintenance availability or unavailable due to Casualty Report, category 4 failure. |
Percentage of time an operationally deployed ship is not in a Casualty Report, category 4 failure state over a given operating period. |
| Aircraft Platforms |
Aviation programs with integrated systems, multiple missions. |
Number of available aircraft/Total aircraft inventory. |
Uptime/Total Time. |
| Ground Vehicles or Mobile Ground Systems |
Wheeled or tracked platforms, either towed or self-propelled. |
Number of available vehicles/Total vehicle inventory. |
Uptime/Total Time. |
| Weapons |
Single use (e.g., air-launched weapons, missiles). |
Number of available weapons/total weapon inventory. Repairable devices must include the pipeline or depot inventory. |
Number of times system is available/number of times system is required. |
| Satellite Systems (including hosted payloads) |
Sub-types include an individual, single purpose satellite, a constellation of two or more satellites, and hosted payloads that share certain satellite infrastructure functions. |
Unless unique circumstances exist (e.g., periodic software uploads), once the system is on-orbit Materiel Availability is not applicable. |
Functional Availability: the probability of satisfying the minimum level of performance for a specific mission as a function of time. Typically expressed as a probability of success.
(Notes 1 & 2) |
| Modification Programs |
Replacement or upgrade of existing systems or subsystems.
(Note 3) |
Determine applicability dependent on existing system type. |
Up Time/Total Time. |
| Subsystems |
Clearly defined interfaces, installed in host platform. |
Number of available subsystems /Total subsystem inventory. |
Up Time/Total Time. |
| System of Systems or Unmanned Systems |
Collection of distinct system elements that create a combined mission capability. (Define Am, Ao, Reliability parameters for each system element) |
Number of available systems/ total system inventory. |
Uptime/Total time. |
Notes:
1. Hosted payloads: Functional Availability may also be a function of the reliability of shared infrastructure depending on the CONOPS.
2. Constellation: Functional Availability is a function of the reliability of the necessary minimum of satellites and the mission success criteria.
3. Modification Systems should consider the existing system requirements structure. |
Table 1. Recommended Sustainment KPP Metrics
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Page Information
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Page Views
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14,194
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Created on
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10/4/2010
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Modified on
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3/16/2016
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Last Reviewed
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3/16/2016
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