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Supportability Design Objectives


Alternate Definition

Supportability and supportability-related design efforts are conducted “to establish quantitative operations and support characteristics of alternative design and operational concepts; and support related design objectives, goals and thresholds, and constraints for inclusion in requirement, decision, and program documents and specifications.”

Alternate Definition Source

Military Handbook (MIL-HDBK) 502A, Product Support Analysis, Activity 8, Supportability and Supportability Related Design Factors (paragraph 5.3.6)

General Information


Supportability design objectives are ultimately tied to the Sustainment Key Performance Parameter (KPP) of Availability and supporting Key System Attributes (KSA). Per the Joint Capability Integration Development System (JCIDS) Manual, the Sustainment KPP/KSA requirements are as follows:

  • Materiel Availability (Am) (Number of Operational End Items / Total Population) - the percentage of the total inventory of a system operationally capable, based on materiel condition, of performing an assigned mission.
  • Operational Availability (Ao) (Uptime/(Uptime + Downtime)) - the percentage of time that a system or group of systems within a unit are operationally capable of performing an assigned mission.
  • Reliability (R) - 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.
  • Operating & Support (O&S) Cost KSA - ensures that the total O&S costs across the projected life cycle associated with Am, Ao and R are considered in making decisions.
  • Maintainability -  The measure of the ability of the system to be brought back to a readiness status and state of normal function. 

Supportability Design Objectives within the Product Support Analysis (PSA) Process

MIL-HDBK-502A defines the PSA process as a wide range of analyses that are conducted within the Systems Engineering (SE) process. The PSA process includes a basic introduction to the ideas of Concept of Operations (CONOPS), system missions, mission profiles, and system capabilities required to establish functional and performance priorities. Understanding these types of concepts paves the way for decisions about tradeoffs between system performance, availability, affordability, and the cost effectiveness of system operation, maintenance, and logistics support.

There is no single list of supportability considerations as there are so many possibilities, and so many relationships between them. Common considerations include compatibility, interoperability; transportability; reliability; maintainability; manpower; human factors; safety; natural environment effects (including occupational health; habitability); diagnostics & prognostics (including real-time maintenance data collection); and corrosion protection & mitigation.

Supportability design objectives form boundary conditions or goals for both engineering performance and Integrated Product Support (IPS) Element concepts and plans and affect design and operational concepts; identify gross product support resource requirements of alternative concepts; and relate design, operational, and supportability characteristics to system readiness objectives and goals.

For the purposes of the PSA process, primary supportability design objectives include:

  • Logistics Infrastructure and Logistics Footprint
  • Architecture
  • Reliability
  • Maintainability
  • Logistics Technologies

Discussion on each of these objectives is discussed below.

Logistics Infrastructure and Footprint Reduction

This includes all the support required to provide a product to the warfighter. This includes everything needed to maintain logistic operations, e.g., manpower, transportation, storage, space, fuel, equipment etc. They are addressed during as part of a total systems approach which is applied to ensure programs to achieve their stated operational objectives throughout their service life within their life cycle cost and support objectives.

To achieve these goals, the support infrastructure of a system needs to be designed-up front, as the opportunities for decreasing the logistics footprint decline significantly as the system evolves from design to production to deployment. Minimizing the logistics footprint through deliberate and integrated logistics/engineering design efforts means that a deployed system will require fewer quantities of support resources especially:

  • Spares and the supply chain
  • Test, support, and calibration equipment
  • Manpower and personnel requirements (including highly specialized or unique skill/ training requirements)
  • System documentation/technical data


These attributes provide the foundation for supportability and sustainment by providing flexibility and affordability as part of the design tradeoff process. These considerations are perhaps the most critical during the O&S phase when obsolescence and end-of-life issues are resolved through a concerted technology refreshment strategy.  Architecture considerations include:

  • Modular Open Systems Approach (MOSA) - MOSA is a system design strategy that employs modular design, uses widely supported and consensus-based standards for its key interfaces, and has been subjected to successful validation and verification tests to ensure the openness of its key interfaces. 
    • An open architecture is defined as a technical architecture that adopts open standards supporting a modular, loosely coupled and highly cohesive system structure that includes publishing of key interfaces within the system and full design disclosure.
  • The key enabler for open system architecture is the adoption of an open business model which requires doing business in a transparent way to leverage the collaborative innovation of numerous participants across the enterprise permitting shared risk, maximized asset reuse and reduced costs.
  • The combination of open system architecture and an open business model permit the acquisition of open system architectures that yield modular, interoperable systems allowing components to be added, modified, replaced, removed and/or supported by different vendors throughout the life cycle in order to drive opportunities for enhanced competition and innovation, incremental system upgradeability without major redesign during initial procurement and re-procurement.
  • Standardization – addresses parts management, for example, is a design strategy that seeks to reduce the number of unique, specialized, and known risk parts used in a system (or across systems) to enhance standardization, commonality, reliability, maintainability, and supportability. In addition to reducing the need and development of new logistics requirements such as technical data and spares, standardization reduces the logistics footprint and also mitigates parts obsolescence occurrences due to Diminishing Manufacturing Sources and Material Shortages (DMSMS).
  • Commercial Off-the-Shelf (COTS) Items - ttechnology risk is a consideration as the system is developed, and the use of mature technology, including non-developmental and/or standards based COTS software or computer hardware, provides an opportunity to adhere to program cost, schedule, and performance requirements, while minimizing risk.
    • The life cycle management of COTS items must consider the both the technology and logistics implications of supporting commercial items in a military environment. As COTS items may have a relatively short manufacturing life, a proactive DMSMS/Obsolescence approach must be addressed to assess the long-term sustainment of COTS and to avoid/minimize single source options.


In addition to being part of the Sustainment KPP, it is a design characteristic and a primary contributor to a system's operational effectiveness in terms of performance, and suitability in terms of availability, the logistics footprint and O&S cost. Each system must exhibit a level of reliability to be militarily useful, meet user needs and be affordable. Consequently, reliability is a primary design requirement to achieve the specified probability of mission success and minimize the risk of failure within defined availability, cost, schedule, weight, power, and volume constraints.

While performing such analyses, tradeoffs are conducted within the PSA process to address the frequency of outage (reliability), and the duration of outage (maintainability) and the resulting cost (affordability). These tradeoffs are significant drivers in maximizing availability and minimizing the logistics footprint.

The Requirements Management process offers the first opportunity to positively influence a system’s reliability. Trade-offs between reliability, performance, and affordability are necessary to ensure balance between requirements and to maximize availability. It is crucial that a system’s reliability program be planned to produce high confidence the system will meet its reliability threshold (minimum). The Reliability, Availability, Maintainability & Cost (RAM-C) Rationale Report Manual provides guidance in how to develop and document realistic sustainment KPP/KSA requirements with their related supporting rationale; how to measure and test the requirements; and how to manage the processes to ensure key stakeholders are involved when developing the sustainment requirements.

Options to enhance system reliability and achieve the R KSA include:

  • Designing to allow a safety margin;
  • Implementing features that establish redundancy and/or graceful degradation;
  • Fail safe features (e.g., in the event of a failure, systems revert to a safe mode or state to avoid additional damage and secondary failures). Features include real time reprogrammable software, or rerouting of mission critical functions during a mission;
  • Calibration requirements; and
  • Reliability Growth Test (RGT) Program.


Maintainability is a design characteristic that reduces the maintenance burden and supply chain by reducing the time, personnel, tools, test equipment, training, facilities and cost to maintain the system.

Maintainability engineering includes the activities, methods, and practices used to design minimal system maintenance requirements and associated costs for preventive and corrective maintenance as well as servicing or calibration activities. Maintainability must be designed-in early in the process to provide effective troubleshooting and repair capabilities at all levels of indenture. Intrinsic maintainability characteristics include:

  • Modularity - The packaging of components such that they can be repaired via “remove and replace” action vs. “on-board” repair. Trade-offs to evaluate replacement, transportation, and repair costs are conducted to determine the most cost-effective approach.
  • Interoperability - The compatibility of components with standard interface protocols to facilitate rapid repair and enhancement/upgrade through modular “black box” technology using common interfaces. Physical interfaces should be designed so that only the correct mating between components is possible.
  • Physical accessibility - The designed-in structural assurance that components requiring monitoring, checkout, and maintenance can be easily accessed. Maintenance points should be directly visible and accessible to maintainers, including access for corrosion inspection and mitigation
  • Designs that minimize preventative maintenance (PM)- to ensure a minimal user workload.
  • Embedded training and testing - with a preference for approved DoD Automatic Test Systems (ATS) families, when it is determined to be the optimal solution from an affordability and availability perspective
  • Human Systems Integration (HSI) - to optimize total system performance and minimize life cycle cost. This includes all HSI domains including the following:
    • Manpower
    • Personnel
    • Training
    • Human Factors Engineering (HFE)
    • Environment, Safety, Occupational Health (ESOH)
    • Survivability
    • Habitability

All the above need to be considered in order to design systems and incorporate technologies that require minimal manpower, provide effective training, can be operated and maintained by users, are suitable, habitable and safe with minimal environmental and occupational health hazards, and survivable for both the crew and the equipment.

Logistics Technologies

DoDI 4151.22 Condition-Based Maintenance Plus (CBM+) details the application of diagnostic and prognostic capabilities, technologies, processes, and procedures to determine maintenance requirements based on real time assessment of system condition obtained from embedded sensors. When coupled with Reliability Centered Maintenance (RCM), CBM+ can reduce maintenance requirements, downtime, and the logistics footprint.

The goal of CBM+ is to perform as much maintenance as possible based on tests and measurements or at pre-determined trigger events, such as physical evidence of an impending failure provided by diagnostic or prognostics technology or inspection, the operating hours completed, elapsed calendar days, or scheduled maintenance. Key considerations in implementing this concept include:

  • Use of diagnostics monitoring/recording devices and software providing the capability for fault detection and isolation, to signal the need for maintenance and convey system status to the operator and maintainer.
  • Use of prognostics monitoring/recording devices and software monitoring to indicate out of range conditions, imminent failure probability, and similar proactive maintenance optimization actions to increase the probability of mission success and anticipate the need for maintenance.
  • Maintenance strategies that balance scheduled (preventive) maintenance and minimize unscheduled corrective maintenance with risk.
  • Hardware architecture - system health monitoring and management using embedded sensors; integrated data
  • Software architecture - decision support and analysis capabilities both on and off equipment; appropriate use of diagnostics and prognostics; automated maintenance information generation and retrieval
  • Design - open system architecture; integration of maintenance and logistics information systems; interface with operational systems; designing systems that require minimum maintenance; enabling maintenance decisions based on equipment condition
  • Processes - RCM analysis; a balance of corrective, preventive, and predictive maintenance processes; trend-based reliability and process improvements; integrated information systems providing logistics system response; Continuous Process Improvement (CPI); Serialized Item Management (SIM)
  • Communications - databases; off-board interactive communication links
  • Tools - integrated electronic technical manuals (i.e., digitized data) (IETMs); automatic identification technology (AIT); item-unique identification (IUID); portable maintenance aids (PMAs); embedded, data-based, interactive training
  • Functionality - low ambiguity fault detection, isolation, and prediction; optimized maintenance requirements and reduced logistics support footprints; configuration management and asset visibility.

In accordance with CBM+ Guidebook, the elements of CBM+ should be revisited as the life cycle progresses, conditions change, and technologies advance. Consequently CBM+ should be considered and revisited in each life-cycle phase.

More on Logistics Technologies

Program Managers (PM) can minimize life-cycle cost while achieving readiness and sustainability objectives through a variety of methods in the design of the system and its maintenance / sustainment program. The following technologies should be considered to improve maintenance agility and responsiveness, increase availability, and reduce the logistics footprint:

  • SIM – As briefly mentioned above (and in depth in DoD Instruction (DoDI) 4151.19, Serialized Item Management) SIM program capabilities facilitate asset visibility and the collection and analysis of failure and maintenance data. SIM programs are structured to provide accurate and timely item related data for ensuring the marking of the population of select items, such as repairable parts, limited life parts, and items that required tracking at the part number level. SIM techniques including the use of AIT such as IUID technology, and Radio Frequency Identification (RFID) using data syntax and semantics. (See International Organization for Standardization (ISO) 15418 and ISO 15434.)
  • AIT - is an integral element of serialized item management programs. IUID markings and accompanying AIT capabilities facilitate paperless identification, automatic data entry, and digital retrieval of supply and maintenance related information. The program has a wide range of technologies from which to choose, ranging from simple bar codes to radio frequency identification technology.
  • Special Handling or Supportability Factor - Specialized facilities for Packaging, Handling, Storage, And Transportation (PHS&T) may be driven by physical parameters such as size, weight, shape and sensitive materials. Transportability factors may include set up and teardown times and/or the ability to transport systems without disassembly and reassembly.

In choosing the specific technology, the PM should consider that the technology will change over the life cycle both for the program and the supply chain management information systems using the information. Consequently, it is important the PM take into account the need to plan for and implement an iterative technology refreshment strategy. In addition, since AIT is used by supply and maintenance management information systems it is important that items selected for serialized item management be marked in conformance with MIL STD 129, Military Marking for Shipment and Storage.


The total asset ownership cost is much more than simply the purchase price, but also includes maintaining and supporting it throughout its projected cycle. The purpose of the PSA process is to define, analyze, and quantify the asset's support requirements in order to influence the design of the asset to improve supportability. Defining and assessing necessary support resources through the life of an asset provides the information needed to reduce cost drivers while improving the efficiency of providing support.

The results of the analysis – the output of the PSA – is the Logistics Product Data (LPD). This is a structured repository cataloguing the data used in or resulting from the PSA. This data can be used, reused, and repurposed in many ways, such as creating a benchmark for a future similar program or design change, or for creating ancillary IPS Element support documents, such as technical documentation.