Attachment 0009- Failure Definition and Scoring Criteria (FDSC).docx

Reliability Failure Definition and Scoring Criteria (FDSC)

Water Storage and Distribution System (WSDS)

Final Version 1 18 December 2020

U.S. Army Futures Command Futures and Concepts Center Futures Integration Directorate RAM Engineering Division B5020, A Ave Fort Lee, VA 23830

DISTRIBUTION STATEMENT A: Approved for public release: distribution unlimited.

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Reliability Failure Definition and Scoring Criteria (FDSC)

Water Storage and Distribution System (WSDS)

Final Version 1

Harishkumar Doshi

U.S. Army Futures Command

Futures Integration Directorate RAM Engineering Division B5020, A Ave Fort Lee, VA 23830

DISTRIBUTION STATEMENT A: Approved for public release: distribution unlimited.

FOUO//UNCLASSIFIED

Foreword

Purpose: The Failure Definition and Scoring Criteria (FDSC) provides the Army Futures Command/Futures and Concepts Center (AFC/FCC) an operationally relevant failure definitions and scoring criteria for Reliability related test incidents scoring. It is the User's primary tool for scoring and evaluating systems during developmental and operational testing events. The FDSC drives system design, development, and testing and evaluation. This document provides the Army Capability Developer, Materiel Developer and Evaluator relevant essential functions, failure definitions and scoring criteria for use by the Reliability Scoring Conference members.

System Description: The Water Storage and Distribution System (WSDS) is the Army’s primary large potable water bag farm storage and issuing capability and comes in five capacities: 20,000 (20K), 40,000 (40K),100,000 (100K) 300,000 (300K) and 800,000 (800K) gallons (GAL). This system was originally Type Classified in September 1981 and the first unit was equipped in February 1983. It is comprised of collapsible storage tanks, engine driven centrifugal water pumps, meters, hoses, fittings and nozzles. The system also has hypochlorination units that automatically chlorinates water to Army standards. It interfaces with the Tactical Water Distribution System (TWDS) as well as all mobile bulk distribution assets to include the 5K GAL Semitrailer Mounted Fabric Tank (SMFT), Load Handling System Water Tankrack (Hippo), Unit Water Pod System (Camel), Unit Water Trailer (Buffalo) and the Unit Water Trailer (Bison) systems.

Point Of Contact: Mr. H. Doshi, Futures and Concepts Center, Futures Integration Directorate, RAM Engineering Division, Fort Lee Field Office, Commercial 804-734-1521, email: harishkumar.o.doshi.civ@mail.mil.

Certification:

1 October 2020 Jeffrey Higgins Date Chief, Central RAM Engineering Branch RAM Engineering Division Futures Integration Directorate

Army Futures Command

Table of Contents

List of Figures Figure 1. Scoring Process Flow Chart 9

List of Tables None

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ii iv

Chapter 1 - Introduction

1.1 Purpose

The Water Storage and Distribution System (WSDS) Failure Definition and Scoring Criteria (FDSC) provides reliability failure definitions and functionality thresholds applied during reliability design, testing and assessment. The FDSC provides the methodology for scoring/categorizing test data. AR 702-19[footnoteRef:1] (RAM) mandates FDSCs as part of RAM requirements. The Army Futures Command (AFC) FDSC Writers Guide[footnoteRef:2] contains Army format and guidelines for FDSCs. [1: Army Regulation 702-19, Reliability, Availability, and Maintainability, p. 12.] [2: Guide for Developing Reliability Failure Definition and Scoring Criteria (FDSC)]

1.2 System Description

The Water Storage and Distribution System (WSDS) is the Army’s primary large potable water bag farm storage and issuing capability and comes in five capacities: 20,000 (20K), 40,000 (40K),100,000 (100K) 300,000 (300K) and 800,000 (800K) gallons (GAL). This system was originally Type Classified in September 1981 and the first unit was equipped in February 1983. It is comprised of collapsible storage tanks, engine driven centrifugal water pumps, meters, hoses, fittings and nozzles. The system also has hypochlorination units that automatically chlorinates water to Army standards. It interfaces with the Tactical Water Distribution System (TWDS) as well as all mobile bulk distribution assets to include the 5K GAL Semitrailer Mounted Fabric Tank (SMFT), Load Handling System Water Tankrack (Hippo), Unit Water Pod System (Camel), Unit Water Trailer (Buffalo) and the Unit Water Trailer (Bison) systems.

1.3 Limitations

There is no intent to address every situation that will arise during WSDS reliability testing. When discovering limitations to the FDSC, the capability developer in coordination with the materiel developer and independent evaluator will update and add appropriate information to the FDSC. An annex is included that summarizes all future changes and/or revisions.

Chapter 2 - Essential Functions

2.1 Essential Functions (EF)

The following subparagraphs provide a list of essential functions (EF) with statements that provide a description of the primary operations that the WSDS must be capable of performing. The EFs are traceable to and must meet performance levels under the conditions specified in the Capability Production Document (CPD) and Operational Mode Summary/Mission Profile (OMS/MP). The WSDS’s EF includes water storage, water distribution and chlorination and pumping.

2.2 Water Storage

This essential function includes the ability to layout the fabric tanks with reasonable effort, safely store water as when receiving and issuing via pump and remain leak free in a reasonable period of time.

2.3 Water Distribution

This essential function includes distribution of water. The pump and distribution system consisting of manifolding, hose reels, hoses, valves, couplings, and nozzles must allow the distribution to perform water delivery at throughput rates consistent with pump rating and receiving entities acceptance rate.

2.4 Chlorination

This essential function includes the chlorination of the water as per chlorination system in compliance with Sanitary Control and Surveillance of Field Water Supplies (TB MED 577).

2.5 Pumping

This essential function includes ability to pump for storage and distribution of water.

Chapter 3 - Failure Definitions

The failure definitions address system failures in the evaluation and scoring of reliability. A failure is an event or inoperable state in which an item or part of an item does not or would not perform to standard due to a malfunction. These definitions focus on essential functions rather than missions. Failure categories include Rapidly Recoverable Events (RRE), Essential Function Failures (EFF), System Aborts (SA), Non-Essential Function Failures (NEFF), and Dependent Events (DE). Any Class III water, or oil leak that cannot be immediately corrected by the operator (within 15 minutes) will be considered EFF and any fuel leak will be scored as SA. See definitions below:

Class

Hydraulic Leak Description Applicable to Oil

Dust-Free: Non-recurring fluid Dusty: Dry collection which does not propagate

Dust-Free: Recurring fluid that does not result in the formation of a droplet Dusty: Moist thin layer (under 3 mm) of dust

Dust-Free: Recurring fluid that results in the formation of a nonfalling droplet.

Dusty: Moist thick layer (over 3 mm) of dust with wetness near the sealing member

Dust-Free: Recurring fluid where a droplet forms and falls Dusty: Recurring fluid forms on vertical surfaces, dripping occurs at bottom of surfaces or pools of oil collect on the top of horizontal surfaces.

Dust-Free: Recurring fluid where the frequency of droplets makes a measurable stream Dusty: Recurring fluid where the frequency of droplets makes a measurable stream

The following applies to water leak only:

Class I: Seepage of fluid (as indicated by wetness) or leakage great enough to form drops, but not enough to cause drops to fall.

Class II: Leakage great enough to result in more than a slow dripping from the leaking item.

Class III: Rapid dripping or spray deemed to be a safety hazard or has the potential to damage other equipment.

3.1 Rapidly Recoverable Event (RRE)

A RRE is a malfunction normally scored as an EFF (or SA) which the maintainer or crew is able to correct within established time constraints through the execution of prescribed maintenance, repair, or on-board diagnostics using authorized and documented procedures with normally available or on board authorized tools, repair parts, equipment, and spares. The cumulative effect of multiple RREs or the cumulative duration of all RREs may result in scoring the event/series and subsequent events as an EFF. As an example, first event scored RRE (10 minutes to correct), second occurrence scored RRE (10 minutes to correct), and third event scored EFF or SA (>30 minutes or loss of EF >30 minutes). It is possible to have multiple EFFs because of a continuing RRE. An event becomes an EFF when the cumulative duration of RRE(s) is > 30 minutes or when three (3) or more RREs of same kind occur during storing and distributing water. An event becomes a SA when the duration of the RRE(s) is > 30 minutes and affects an EF.

3.2 Essential Function Failure (EFF)

An EFF is an event that results in significant degradation or loss of an essential function. Correction/repair of all EFFs must occur upon landing or mission completion prior to the start of the next mission. All EFFs are serious failures since they affect an essential function.

3.3 System Abort (SA)

A SA is an event that involves the significant degradation or loss of one or more essential functions, rendering the WSDS ineffective in its current operation. An SA is an EFF causing immediate removal from service in an operational environment or precluding the WSDS from starting an EF.

3.4 Non-Essential Function Failures (NEFF)

An NEFF is an event that does not result in operationally significant degradation or loss of an essential function. An NEFF will have an obvious indication of a malfunction or abnormal equipment condition and will normally require maintenance/corrective action to remedy the failure. An NEFF-related corrective action is deferrable to the next maintenance period (allowing follow-on operations to occur before repair).

3.5 Dependent Event (DE)

A DE is a secondary failure induced by the primary malfunction and typically occurring simultaneously or near simultaneously with the primary event. Analysis of the failure event must positively confirm that it occurred as the direct result of a specified primary event.

Chapter 4 - Scoring Process

Reliability Scoring Conference (RSC) members use the scoring definitions and criteria within the FEM to score proper categories, sub-categories, and chargeability (cause) during the scoring conference. Figure 1 is an example flow chart depicting a typical scoring process. The scoring members may revise the scoring process as needed based on the failure definitions and events observed. Appendix B – Glossary includes definitions used in the scoring process.

Figure 1. Scoring Process Flow Chart For each test event reported on a test incident report (TIR), the first step is to choose a primary classification based on its relevance to reliability. The three primary classification categories are: “Reliability Failure Event”, “Non-Reliability Event”, and “Other Test Event.” Figure 1 depicts the general scoring process.

4.1 Scoring.

Select the appropriate category below and proceed in accordance with directions:

4.2 Reliability Failure Event

Identify the event as one of the following categories at both the system level and component level (when appropriate), then proceed to 4.5 (Cause).

· System Abort.

· Essential Function Failure.

· Non-Essential Function Failure.

· Rapidly Recoverable Event.

· Dependent Event.

4.3 Non-Reliability Event

Identify the event as one of the following and proceed to next event/incident.

· Preventive maintenance, checks, or services (PMCS).

· Scheduled maintenance

· Routine operating procedures (ROP).

· On-Condition maintenance

· Other (Specify)

4.4 Other Test Event

Assign event to one of the following failure categories. Then, proceed to next event/incident.

· Pre-test/Post-test checkout.

· Equipment Modification.

· Test Peculiar Event (TPE).

· Abuse or Misuse.

· Unrelated Damage.

· Non-RAM Oriented.

· Performance Limitation.

· Other (Specify).

4.5 Cause

The last step for reliability failure events is to assign an appropriate cause. Identify the cause of the event from the following list. Then, proceed to next event/incident.

· Accident.

· Support Equipment.

· Indeterminate.

· Tech Document/Manuals.

· Primary Failure.

· Hardware.

· Software.

· Operator (Crew).

· Maintenance Personnel.

· Training.

· Other (Specify).

Chapter 5 - Test Data Collection Guidance The following recommendations assist in maintainability evaluation of the system. TIRs document all incidents where a system is non-operational, operates with degraded performance, or responds differently than expected. They should contain as much information as possible with regard to failures and when possible to the possible root cause of the failures.

· Failure initiation date (date, time, location, malfunction indicators)

· System operation(s) attempted at time of failure

· Operating hours, miles, cycles, or other measurement(s) used to quantify the age or life of the system component at time of failure

· Maintenance actions performed, e.g. Scheduled, Unscheduled

· Maintenance level used

· Maintenance man-hours

· Maintenance clock-hours

· Military Occupational Specialty (MOS) used

· Spare or repair parts used

· Petroleum, oil, and lubricant (POL) quantity used

· Indication of built-in-test/built-in-test-equipment (BIT/BITE) false alarm

· Indication of BIT/BITE successful detection

· Indication of BIT/BITE successful isolation

Appendix A – Update/Revision History 18 December 2020: This is the first version as 1.

A-1

A2 Appendix B – Glossary Abuse or Misuse. Events in which official test participants (crewmembers or maintenance personnel) cause damage to the system either willfully or through gross negligence are subject to being classified as abuse (ultimately, a decision for the Scoring Conference members to make after considering the facts). This category also includes any incidents in which the tester directs the deliberate misuse of the system (e.g. a test excursion to exceed the performance limits of the system), whether called for by the test plan or not.

Accident. Failure Chargeability category for accident induced failure/damage not attributable to the design of the system or operator negligence.

Built-in Test (BIT). An integral capability of the mission system or equipment that provides an automated test capability to detect, diagnose, or isolate failures.

Built-in Test Equipment (BITE). Hardware that is identifiable as performing the built-in test function.

Crew/Operator. Failure chargeability category that includes all incidents attributable to crew/ operator error.

Dependent Event. A reliability event that is a secondary malfunction caused by the failure of another item, which normally occurs simultaneously or nearly simultaneously with the causing event.

Equipment (System) Modification (hardware or software). Installation of hardware kits, software modifications, or incorporation of redesigned components or software upgrades.

Essential Function Failure (EFF). An EFF is an event that results in significant degradation or loss of an essential function. Correction/repair of all EFFs must occur upon landing or mission completion prior to the start of the next mission. All EFFs are serious failures since they affect a mission essential function.

Essential Maintenance Action (EMA). An EMA results from any incident or malfunction which causes the inability to perform, or degrades, one or more EFs regardless of time of discovery, plus any additional unscheduled maintenance required prior to initiating the next mission, to include restoring mission essential equipment redundancy.

Hardware. Chargeability category that includes malfunctioning hardware as well as personnel related incidents that are attributable to the hardware's design. This category may be broken down further into hardware that is “Contractor Furnished Equipment (CFE)” and/or “Government Furnished Equipment (GFE)”.

Maintainability. A measure of a system’s ease of maintenance.

Maintenance Personnel. This chargeability category includes all incidents attributable to maintenance personnel errors not due to hardware/software design/coding problems, poorly written manuals, human factors/ergonomic issues, or faulty embedded diagnostics.

B-1

Malfunction. A specified action or activity not properly performed.

Non‑Essential Function Failure (Non-EFF). An NEFF is an event that does not result in operationally significant degradation or loss of an essential function. An NEFF will have an obvious indication of a malfunction or abnormal equipment condition and will normally require maintenance/corrective action to remedy the failure. An NEFF-related corrective action is deferrable to the next maintenance period (allowing follow-on missions to occur before repair).

Non-RAM Oriented/Information. Category for Test Incident Reports (TIR) excluded from RAM computations. Examples include suggested improvements, reports on inadequate test procedure, unusable or unacceptable replacement parts discovered prior to or during installation, test schedule delays, suggested human factors improvements or recommended changes to the system support package not related to a specific test event.

Non-Reliability Event (Applicable to Maintainability). An Event that is not a reliability failure, but may have implications on system maintainability.

On-Condition/Condition Based Maintenance (CBM). Incident recording maintenance performed to replace a used or worn part/component that has met its life expectancy criteria (i.e., its durability or service life requirement). The part must still be functioning at the time of its replacement. The system technical documentation must have specific criteria to identify conditions for replacement. Examples of “on-condition” maintenance include replacement of tires due to normal wear (tread wear indicators showing/tread depth less than “wear-out” standards) or gun tube replacement based on the specified item meeting the necessary interval (e.g. rounds, hours, or miles), or durability requirements. It may be necessary to further record whether the item replaced is Contractor Furnished Equipment (CFE) or Government Furnished Equipment (GFE), depending on the nature of the R&M requirements.

Other Test Event (OTE) (Not Applicable to RAM). Events not applicable to RAM evaluation of the system.

Performance Limitation. Inability of a system to meet performance specifications without incurring a malfunction. The classic example is a vehicle with a speed requirement of 90 miles per hour (mph). However, the design of the drivetrain prevents the vehicle from ever reaching the required speed. No malfunction has occurred which prevents the achievement of the required speed.

Pre-test/Post-test Checkout. Events observed during burn-in, pre-test/post-test inspection, or other pre-test/post-test activities.

Preventive Maintenance, Checks and Services (PMCS). Maintenance actions of a preventive nature normally performed by operator or crew.

Primary Failure. Category for failure events caused by an earlier or concurrent primary failure. This category applies to those events scored as dependent failures.

B-2

Rapidly Recoverable Event (RRE). A RRE is a malfunction normally scored as an EFF (or SA) which the maintainer or crew is able to correct within established time constraints through the execution of prescribed maintenance, repair, or on-board diagnostics using authorized and documented procedures with normally available or on board authorized tools, repair parts, equipment, and spares.

Reliability. Probability that an item can perform its intended function without failure for a specified time interval under stated conditions.

Reliability Event. This category captures any test incidents that document failure or malfunction of an item.

Reliability Event Chargeability. Section of the scoring criteria documenting the root cause of a failure.

Routine Operating Procedures (ROP). Operating procedures routinely performed by the operator & prescribed in the user manual. Typically, they are tasks the operator or crew may quickly perform and are not reliability failures. (Note: These do not include maintainer tasks that may be addressed in some user manuals.) This is not a catch all category that accounts for ANY crew/operator correction within a specified time limit. The intent is to not penalize a system for needing a minor, quick remedy, using only on-board spare or repair parts that is considered a normal, routine operating procedure in the operator's manual. These procedures should be based on how quickly and easily the crew or operator can do the task without impact on mission accomplishment, crew safety, etc. If frequency of occurrence is an issue, the manuals should address unacceptable recurrence. If the constraint is exceeded, the events will be recorded on their own merits as failures with associated maintenance demands.

Scheduled Maintenance. Maintenance actions performed by a maintainer in accordance with applicable technical documentation/manuals.

Software. This chargeability category includes all incidents attributable to software contained within the system (application, interface, or firmware). This category may be broken down further into software that is “Contractor Furnished Equipment (CFE)” and “Government Furnished Equipment (GFE)” Software.

Support Equipment. Chargeability category for incidents caused by special tools, common tools, Test Measurement and Diagnostic Equipment (TMDE), software programs, or other equipment not a component of the operational system.

System Abort (SA). A SA is an event that involves the significant degradation or loss of one or more essential functions, rendering the WSDS ineffective in its current operation.

Technical documents/Manuals. This chargeability category includes all events that are attributable to misleading, incorrect, or nonexistent‑but‑needed information in the technical documents/manuals.

B-3

Test Peculiar. Malfunctions caused by outside equipment not part of the system under test or people not acting as test players (crew or maintenance personnel). Score engineering evaluations to analyze the cause of test peculiar malfunctions, as well as any malfunctions and/or maintenance efforts caused by the engineering evaluation as "OTE". This also includes maintenance evaluations conducted as a part of the test plan and malfunctions to or caused by test peculiar instrumentation.

Training. This includes any event attributed to inadequacies in training due to omitted or incorrect training procedures, or inappropriate training material such as information above the general level of understanding of the target audience.

Unrelated Damage. This includes damage caused by natural phenomena (e.g., lightning, earthquakes, etc.) or other influences beyond control of the operational elements of the system.

Unscheduled Maintenance Action (UMA). A UMA is any maintenance action not identified in the technical documentation of the system as scheduled maintenance.

Unknown. Incidents that do not have sufficient information/data to permit a determination of chargeability.

B-4 Appendix C – References

Army Regulation (AR) 702-19. Reliability, Availability, and Maintainability. Headquarters Department of the Army Washington, DC. 12 February 2020

WSDS Capability Production Document (CPD), Version 4.2, dated 10 March 2017.

WSDS Clarification Memo #2, dated 1 June 2020.

WSDS Operational Mode Summary/ Mission Profile (OMS/MP) dated 1 June 2015.

Army Techniques Publication (ATP) 4-44, Water Support Operations, dated 2 October 2015

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