ATTACHMENT_0017_-_Failure_Definition_Scoring_Criteria_(FDSC).pdf

M917A3 ATTACHMENT 0017

ARMY CAPABILITIES INTEGRATION CENTER

CAPABILITIES DEVELOPMENTS DIRECTORATE (CDD)

CAPABILITIES ASSESSMENT AND RELIABILITY, AVAILABILITY, and

MAINTAINABILITY (RAM) DIVISION (CARD)

FAILURE DEFINITION AND SCORING CRITERIA (FDSC)

for the

HEAVY DUMP TRUCK (HDT)

M917A3

18 November 2014

PREPARED FOR

UNITED STATES ARMY MANEUVER SUPPORT CENTER

CAPABILITIES DEVELOPMENT AND INTEGRATION DIRECTORATE

REQUIREMENTS DETERMINATION DIVISION

ASSURED MOBILITY AND ENGINEER REQUIREMENTS DIVISION

PREPARED BY

TRAINING AND DOCTRINE COMMAND

ARMY CAPABILITIES INTEGRATION CENTER

CDD, CARD

RELIABILITY, AVAILABILITY AND MAINTAINABILITY (RAM) ENGINEERING BRANCH

LEONARD WOOD FIELD OFFICE

14000 MSCOE LOOP, SUITE 104

FORT LEONARD WOOD, MO 65473

“Excellence in Engineering, Scientific, Technical, & Analytical Services for the Combat Developments Community” ii i

FAILURE DEFINITION AND SCORING CRITERIA (FDSC)

for the

HEAVY DUMP TRUCK (HDT)

CERTIFICATION SHEET

Purpose: This FDSC supports the Reliability and Maintainability (R&M) requirements as established in the HDT Capability Production Document (CPD). It will be used to determine classification and chargeability of test incidents, which occur during R&M related testing for the system. Further, it will be used for establishing an agreed upon data base to project operational

R&M values for estimates of operational effectiveness and ownership costs, as well as determining compliance with established reliability requirements in the HDT CPD and contractual specifications.

System Description: The HDT is a large capacity truck with a cargo area that can transport and dump material used in construction by engineer units in support of air and ground line of communication and theatre infrastructure repair and restoration operations. Construction units require extensive haul capability to move rock, crushed aggregate, hot mix asphalt, wet or dry sand, earth, and rubble (to include concrete with re-bar) to processing or construction sites. The material is unloaded by tilting the bed. The rate of discharge is controlled by the operator and may be combined with the forward movement of the vehicle such that a uniform deposit is formed on the dumping surface. The rate of discharge may further be assisted by a multi-chute material control system.

Point of Contact: Mr. Gary Pryor, Commercial 573-563-7345, email:

gary.a.pryor.civ@mail.mil.

Certification: Date: 18 Nov 2014

GARY A PRYOR

Central Region Manager

RAM Engineering Branch

FAILURE DEFINITION SCORING CRITERIA (FDSC)

for the

HEAVY DUMP TRUCK

1. PURPOSE.

a. The FDSC serves as a tool for directing/guiding Reliability Scoring Integrated Process

Team (IPT) members through the test incident/event scoring process with the intent of eliminating as much subjectivity from the scoring process as possible. The purpose of the

Failure Definition is to define, from the user's perspective, degraded system performance which, when evidenced by component or subsystem malfunctions, is considered a failure. The purpose of the Scoring Criteria is to define a specific and agreed upon process for scoring incidents/events which occur during reliability and maintainability related testing (such testing should be conducted in accordance with the approved Operational Mode Summary/ Mission

Profile (OMS/MP)). The scoring process involves the classification of each incident/event into the proper category (based upon its impact on the HDT operational performance/functionality) followed by charging the cause of the incident to a particular source.

b. It will be used for establishing an agreed upon data base which will be used to project operational R&M values for estimates of operational effectiveness and ownership costs, and to determine compliance with established reliability requirements in the HDT CPD and Purchase

Description. Further, it is written under U.S. Army Training and Doctrine Command

(TRADOC) format and guidelines.

2. SYSTEM DESCRIPTION. The HDT is a large capacity truck with a cargo area that can transport and dump material used in construction by engineer units in support of air and ground line of communication and theatre infrastructure repair and restoration operations. Construction units require extensive haul capability to move rock, crushed aggregate, hot mix asphalt, wet or dry sand, earth, and rubble (to include concrete with re-bar) to processing or construction sites.

The material is unloaded by tilting the bed or using a ram ejector mechanism to discharge the material from the cargo area. The rate of discharge is controlled by the operator and may be combined with the forward movement of the vehicle such that a uniform deposit is formed on the dumping surface. The rate of discharge may further be assisted by a multi-chute material control system.

3. FAILURE DEFINITION. The HDT must execute the following essential functions, and be capable of performing these functions in all scenarios/mission profiles depicted in the OMS/MP.

a. Essential Functions. An essential function is a generic statement which provides a fundamental description of the primary or basic operations which a system must be capable of performing from a user perspective. If the system under test does not have the capability to perform an essential function due to known performance limitations, test limitations, or configuration maturity limitations, such incidents will not be subject to reliability scoring. Prior to any test event all known capability/performance limitations will be identified in a “Statement of Limitation” document and made available to members of the RAM scoring conference. The

“Statement of Limitations” document is not part of this FDSC and its determination is outside the scope of this FDSC. This exception to reliability scoring does not apply when the system is unable to perform an essential function due to a malfunction.

(1) Move. The mobility system must be capable of effectively maneuvering such that the system can complete a round trip mission - to and from the dump site. The vehicle must be able to:

(a) Begin operation without outside assistance.

(b) Maneuver by moving forward and backwards.

(c) Maneuver by steering so as to be functionally and safely controlled by the operator on all roads.

(d) Move with sufficient speed and power to accomplish the missions in the timeframes outlined in the Operational Mode Summary/Mission Profile (OMS/MP).

(e) Tow. Be capable of towing lunette style trailers including provisions for providing electrical power via an electrical coupling.

(f) Maintain and modify tire pressure. The operator will have the capability to maintain and modify tire pressures from inside the vehicle.

(2) Haul and Dump.

(a) The HDT must be capable of individually hauling and dumping a variety of dry and wet loads to include blast rock, concrete with reinforcing bars, dirt, hot asphalt, snow, rubble, large boulders and sand.

(b) Heat Dump Bed Floor. The HDT must be capable of heating, maintaining, and allowing operator control and monitoring of the temperature of the dump bed floor.

(c) Dumping Function. The vehicle must be able to dump whatever materiel it is carrying in it's bed. If equipped with a Material Control System (MCS), the vehicle must be able to dump material in a controlled fashion (by the operator both from within and outside the cab), by opening and closing associated control gates under all normal load conditions and under user control. Inability of the vehicle to spread loads due to material clogging or not flowing thru the gates, when the gates are otherwise fully functional, will not be considered against the reliability of the system, but will be considered when assessing the performance and functionality requirements. Likewise, inability of the gate to close due to material blocking the gate, when the gate is otherwise fully functional, will not be scored against the reliability of the system, but will be considered when assessing the performance and functionality requirements.

(3) Host Communication, Navigation, and Situational Awareness Equipment.

Provide a capability to host (including mounting provisions and power) voice and data communication and navigation devices and external components such as antennae, beacons, alarms, etc., as listed in the CPD. This equipment is considered GFE and is not included in the base platform R&M; power and mounting provisions are considered Contractor

Furnished Equipment (CFE).

(4) Protect and Support.

(a) Force Protection. Provide crew survivability as outlined in the CPD. This function is considered lost if a malfunction results in an inability to meet required force protection capabilities. Battle damage or loss of this essential function not resulting from a malfunction are not counted against reliability criteria.

(b) Maintain Crew Environmental Quality. Provide an environment that does not present a critical or catastrophic hazard to the operator by maintaining adequate internal temperature, and by providing ventilation and air circulation.

(c) Allow for access and egress to/from the vehicle from all hatches, and have the ability to open, close, and secure the hatches in an open or closed position.

b. Failure Definition. For the HDT, the following definitions of failure and clarifications are applicable. A further expansion of failure effects for each essential function is shown in Table 2.

(1) Essential Function Failure (EFF) and System Abort (SA).

(a) An Essential Function Failure (EFF) is defined as an event that results in the loss of or operationally unacceptable degradation in one or more of the essential functions. Table

1 describes allowable degradation in essential functions and provides additional clarifications with regard to the scoring of the loss/degradation of essential functions.

Often, the occurrence of an EFF will not cause mission cessation, but has an significant impact such that it must be repaired prior to the next mission (cannot be deferred).

(b) An EFF is scored as a System Abort (SA) if it results in the loss or degradation of an essential function(s) that renders the system unable to enter service or causes immediate removal from service, deadlines the platform, or makes it non-mission capable (a SA reduces its utility to the point that it is deemed ineffective/unsafe in its primary role).

System abort also includes those malfunctions that create a personal injury related

Category 1 (catastrophic) or 2 (critical) hazard as defined in MIL-STD-882E (see Table 3).

By definition, all SAs are also EFFs and are annotated as “SA/EFF”. An SA may result in a “Not Mission Capable” status under wartime conditions or reduces its utility to the point that it is deemed ineffective/unsafe. By definition all SAs are also EFFs. Therefore, MTBEFF is calculated including System Aborts (SA), and EFF events.

(2) A Non-Essential Function Failure (NEFF) is defined as loss of non-essential functions, degradation of essential functions not meeting the criteria of an EFF, or minor malfunctions related to either essential or non-essential functions which can be deferred to the next maintenance period.

(3) A Dependent Failure is a failure event caused by another related event and which occurs simultaneous or nearly simultaneous to the related causing event. In some cases, it may be necessary to present engineering evidence to clearly link the dependent event to the causing event. The score of the first (primary) incident should reflect the combined effect of the primary and all secondary related failures (EFF, EFF/SA, etc). The secondary incident(s) are scored as Dependent Failures and charged to the failure of the primary incident (using Primary

Incident Chargeability). Thus, the system is charged a single failure event but all related maintenance time is counted. The Dependent Failure score is also sometimes used for TIRs which document the reoccurrence of an intermittent failure event; usually in those cases separate TIRs were written to document failures which were later determined to be instances of the same intermittent failure. The scoring IPT may alternatively choose to annotate or revise the TIR describing the initial occurrence to include subsequent related occurrences.

(4) Rapidly Recoverable Event (RRE).

(a) An incident which meets the conditions of an EFF, but which can be quickly rectified using an authorized operator action/procedure using only normally available tools and equipment is scored as an RRE. This category is intended to cover those infrequent incidents which can be quickly corrected without significant loss of function. An RRE must be a trained recovery activity (e.g., restarting the function/software module, rebooting the system, cycling power), or be readily apparent to the operator (e.g., reattaching a cable). If it is apparent that there is a systemic problem which is being consistently scored as an

RRE, the scoring body may decide to score them either individually or as a group as an

EFF or SA. At the discretion of RAM Scoring Committee members (based on input from test personnel and/or Subject Matter Experts), frequently recurring failures of a particular type (or an excessively high frequency of failures in general) that cumulatively consume an excessive amount of mission time for execution of crew level corrective maintenance may result in a higher level of failure classification (even an EFF or SA) being assigned to address/convey the overall cumulative impact of the failures (in the event that the adverse impact on operations is great enough).

(b) Fifteen minutes is allowed for the conduct of any required troubleshooting and authorized corrective operator-level maintenance actions to restore loss of an essential function.

(c) The frequency of recurring operator correctable incidents (initiated to address the loss or degradation of an Essential Function) may prompt the RAM Scoring Committee to ultimately classify the cumulative effect of such incidents as an SA, if it is obvious that the vehicle’s ability to successfully complete the mission has been substantially degraded or compromised to a critical extent. Accordingly, three recurring RREs executed during an individual mission are subject to being collectively scored as an EFF or SA.

(5) Clarifications.

(a) Failures that are discovered during scheduled maintenance or corrective maintenance for an unrelated failure are normally considered on their own merit, regardless of when they are discovered. Sometimes a failure is discovered which did not exhibit noticeable symptoms or which did not affect operations enough for an investigation to be initiated, but by their nature are serious events (i.e. Class III oil leak). If the crew or maintainer can correct a system abort incident discovered during other maintenance (or

PMCS) within 30 minutes, without requiring a higher level of maintenance, and without requiring any part which would not be normally available, the incident will be considered an EFF only. Normally available parts means parts stocked at the level the repair is being performed (i.e. for repairs being performed by the field level maintainer, normally available repair parts are those available to the maintainer (i.e. Authorized Stockage List (ASL) or

Prescribed Load List (PLL). If the crew finds a problem during PMCS, it must be something he can correct which will normally be limited to tightening fittings, etc – but not using parts from the ASL/PLL. If more than one new failure is discovered at one time, the scoring body should use their judgment as to the scoring of these incidents, taking into account the cumulative maintenance time for all newly discovered failures. All incidents not meeting these guidelines will be scored under their own merits. A failure will be scored on its own merits in cases where a failure is detected on a subsystem during scheduled/corrective maintenance that would have been considered an SA/EFF during the performance of the mission if an attempt had been made to operate the affected subsystem.

(b) Built-In-Test (BIT) / Self-Test false alarms will be scored appropriately as actual malfunctions, unless it is readily apparent to the crew that it is a false indication.

(c) Scoring of leaks. The following table provides general guidance with scoring related to leaks; and reflects a wartime flavor. In peacetime usage, scoring of leaks will be conducted iaw the associated technical manuals.

Table 1. Scoring of Leaks.

• LEAKS. (SUBJECT TO CONSIDERATION OF FLUID TYPE AND LEAK RATE, AND THE

IMPACT OF THE LEAK ON THE ABILITY TO COMPLETE THE ONGOING MISSION OR

BEGIN AN IMMINENT MISSION). GENERAL GUIDELINES:

•• CLASS I (ANY FLUID)

•• CLASS II (NON-FUEL)

•• CLASS II (FUEL)

•• CLASS III FUEL

-- FUEL > 1 DROP/MINUTE

•• CLASS III NON-FUEL

-- NON-FUEL LEAK OF MONITORABLE FLUID

-- NON-FUEL STEADY STREAM OR SPRAY

- SA

X

EFF

NEFF

Table 2 – Failure Definition Expansion

Essential

Function

Failure Examples / Scoring Conventions SA

Move ESSENTIAL FUNCTION FAILURE

Unable to start vehicle (with or without slave start)

Loss of ability of vehicle to safely operate in a controlled manner

Significant degradation (> 30%) in mobility or speed due to malfunction

Loss of ability to tow or be towed

Loss of ability to modify and control tire pressure

Flat Tire

– a tire malfunction which affects mobility which can be corrected by the use of the spare tire

- a tire malfunction which affects mobility and which can not be corrected by the use of the spare tire; or a second occurrence which necessitates a spare tire within

325 miles of the first usage of a spare tire

NON-ESSENTIAL FUNCTION FAILURE

Tire punctures for which the tire pressure can be maintained with the Central Tire

Inflation System

Haul and Dump ESSENTIAL FUNCTION FAILURE

Loss of ability to accept and carry required loads

Loss of ability to dump required loads

Loss of ability to heat dump bed (when required for hot mix loads)

Loss of ability to utilize MCS

No specific failures identified – see General Category (below)

Host

Communication, Navigation, and

Situational

Awareness

Equipment

ESSENTIAL FUNCTION FAILURE

Loss of power or mounting provisions to GFE equipment

Protect and

Support

ESSENTIAL FUNCTION FAILURE

Loss of ability to cool cab (when armored)

Loss of ability to cool cab (when not armored)

Loss of ability to heat cab

Unable to open/close/secure any door

Essential

Function

Failure Examples / Scoring Conventions SA

GENERAL NON-ESSENTIAL FUNCTION FAILURE

Loose bolts which do not degrade an essential function

Table 3. Hazard Severity, MIL-STD-882E

Description Category Environmental, Safety, & Health Result Criteria

Catastrophic 1 Could result in one or more of the following: death, permanent total disability, irreversible significant environmental impact, or monetary loss equal to or exceeding $10M.

Critical 2 Could result in one or more of the following: permanent partial disability,injuries or occupational illness that may result in hospitalization of at least three personnel, reversible significant environmental impact, or monetary loss equal to or exceeding $1M but less than

$10M.

Marginal 3 Could result in one or more of the following: injury or occupational illness resulting in one or more lost work day(s), reversible moderate environmental impact, or monetary loss equal to or exceeding $100K but less than

$1M.

Negligible 4 Could result in one or more of the following: injury or occupational illness not resulting in a lost work day, minimal environmental impact, or monetary loss less than $100K.

4. SCORING CRITERIA. Classification of an event is based upon its impact on system operational performance. Primary classification categories are: “Reliability Failure Event”, “Non-Reliability Failure Event”, and “Other Event or Failure”. Reliability Failure events are divided into Essential Function Failure (EFF), System Abort/EFF (SA/EFF), Non-Essential

Function Failure (NEFF), or Dependent Failure. Once an event has been classified as a failure, chargeability is assigned. Actual maintenance need not be performed in order to assign chargeability. Figure 1 depicts the general scoring process.

Scoring Procedure

a. Select appropriate category below and proceed as directed:

(1) Event is "Reliability Failure”. Proceed to 4.d.

(2) Event is “Non-Reliability Failure ". Proceed to action 4.b.

(3) Event is “Other Event or Failure”. Proceed to action 4.c.

b. Non-Reliability Failure. Identify the event as one of the following and proceed to next event/incident:

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

(2) Scheduled maintenance.

(3) Routine operating procedures performed by crew and prescribed in operator manual.

(4) On-Condition Maintenance.

c. Other Event or Failure. Assign event to one of the following failure categories.

Then, proceed to next event/incident:

(1) Pre-test/Post-test checkout.

(2) System Modification.

(3) Test Peculiar.

(4) Misuse.

(5) Non-R&M Oriented.

(6) Unrelated Damage.

(7) Performance Limitation.

(8) Administrative

d. Reliability Failure. Assign event to appropriate category, then proceed to 4.e

(Chargeability):

(1) EFF

(2) SA/EFF

(3) RRE

(4) Non-EFF

(5) Dependent Failure

e. Chargeability. Identify the cause of the event from the following list:

(1) Accident

(2) Crew

(3) Equipment:

(a) Hardware (HW/CFE or HW/GFE)

(b) Software (SW/CFE or SW/GFE)

(c) Unknown/Indeterminate (UNK/CFE, or UNK/GFE)

(4) Maintenance personnel

(5) Primary Failure (for incidents classified as “Dependent Failures” only)

(6) Support Equipment

(7) Technical Documentation

(8) Training

(9) Unknown, Non-Equipment

SCORING PROCESS

PREVENTIVE MAINTENANCE

CHECKS & SERVICES

(PMCS)

SCHEDULED MAINTENANCE

ROUTINE OPERATING

PROCEDURES

ON-CONDITION

MAINTENANCE

ACCIDENT

CREW

EQUIPMENT (/CFE or /GFE)

-Hardware

-Software

-Unknown

MAINTENANCE PERSONNEL

PRIMARY FAILURE

SUPPORT EQUIPMENT

TECHNICAL

DOCUMENTATION

TRAINING

UNKNOWN (Non-Equipment)

Chargeable Reliability Failures R&M Relevant Non-Failure Events Failures/Events Not Relevant to R&M

Non-Chargeable Reliability Failures

PRE-TEST/POST-TEST CHECKOUT

SYSTEM MODIFICATION

TEST PECULIAR EVENT

MISUSE

UNRELATED DAMAGE

NON-RAM ORIENTED

PERFORMANCE LIMITATION

ADMINISTRATIVE

LEGEND

SELECT FROM OPTIONS SHOWN

BELOW THIS TYPE ICON

PRIMARY FAILURE

CATEGORIES

NON-ESSENTIAL FUNCTION

FAILURE

DEPENDENT

FAILURE

ESSENTIAL FUNCTION

FAILURE

SYSTEM ABORT

Figure 1 -- Generalized Scoring Process

ADDITIONAL FAILURE

CATEGORIES

RELIABILITY

FAILURE EVENT

NON-RELIABILITY

FAILURE EVENT

OTHER EVENT

OR FAILURE

FAILURE CAUSED BY

TEST EVENT

(as recorded on a Test Incident Report (TIR))

RAPIDLY RECOVERABLE

EVENT

5. INSTRUCTIONS FOR TEST DATA COLLECTION. Accurate collection of certain data and information is critical to successful evaluation of a systems R&M performance. Some of this information and data is used by scoring personnel to make final determinations regarding categorization of reliability failures. Maintenance and supply demand categories, defined in a later section, are determined based on the failure category assigned or by definition. Following is a list of data and information that should be collected:

o Maintenance level o MOS performing maintenance o Maintenance clock-minutes/hours used o Maintenance man-minutes/hours used o Spare parts, LRUs, or SRUs used o Repair parts used o POL quantity used o Crew Correctable Maintenance Demand (CCMD) o Scheduled Maintenance Demand (SMD) o Non-Essential Maintenance Demand (NUMD) o Essential Unscheduled Maintenance Demand (EUMD) o Essential Logistics Demand (ELD) o Non-Essential Logistics Demand (NELD)

6. DEFINITIONS.

a. Chargeability Definitions.

(1) Accident. Chargeability category for incidents resulting from a mishap involving operational elements of the system (e.g., hardware, crew, maintainers, test players acting as crew, etc.) and usually resulting in equipment and/or personnel damage that cannot be charged to any other chargeability category. For example, accidents due to careless operations would not be charged to the “Accident” category, but instead would be charged under the “Crew” classification. Also, if the incident was due to faulty hardware design, the incident would be assigned a hardware chargeability, not “Accident”.

(2) Crew: Chargeability category for events attributable to crew error that were not rooted in hardware/software design, inadequate training, or poorly written manuals.

(3) Equipment.

(a) Hardware. Chargeability category for malfunctioning hardware and personnel related events caused by poor hardware design. Failure should be further designated as a failure of GFE, or failure of CFE. Government furnished equipment (GFE) includes the

SINGCARS, Blue Force Tracker, FBCB2, DVE, crew served weapon, and ECM devices.

(b) Software. Chargeability category for malfunctioning software and personnel related events caused by poor software design. Failure should be further designated as a failure of GFE, or failure of CFE.

(c) Unknown/Indeterminate HW/SW. Chargeability category for malfunctioning system (hardware or software) and the malfunction cannot be directly attributed to one or the other at the time of the scoring conference. Failure should be further designated as a failure of GFE, or failure of CFE.

(4) Maintenance Personnel: Chargeability category for events attributable to maintenance personnel errors that were not rooted in hardware/software design problems, inadequate training, or poorly written manuals.

(5) Primary Failure: Chargeability category for secondary malfunctions which are directly attributable to an initial malfunction. For instance, if a surge protector fails and causes a microprocessor to burn up, the microprocessor failure is charged to "Primary Failure" due to the failed surge protector. However, all maintenance to repair both failures is chargeable.

(6) Support Equipment: Chargeability category for events attributable to special tools, common tools, TMDE, spares, repair parts, associated software or other special equipment not part of the operational system.

(7) Technical Documentation: Chargeability category that includes all events attributable to misleading, incorrect, or nonexistent, but needed, information in the manuals. Poorly written manuals may cause crew or maintenance personnel errors. In these cases, manuals should be charged.

(8) Training: Chargeability category that includes any event that can be directly 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. For an event to be charged to training, the instructional information needed must have been included in the manuals.

(9) Unknown (Non-Equipment). Events for which no explanation can be found, and which cannot be tied to a System (Hardware or Software) malfunction. Every attempt should be made to determine the true cause of the failure and place the event in one of the other chargeability categories. Root causes of failures with an unknown chargeability are unlikely to get addressed or fixed.

b. Crew Correctable Maintenance Demand (CCMD). The CCMD is used to capture events where the crew corrected failures. These maintenance actions must be authorized at the crew level in the TM or applicable documentation. Each failure event should be recorded based on its impact on system performance, regardless of who accomplishes the corrective action. An event scored on its own merits and fixed by the crew generates a CCMD. An EFF corrected and authorized by the crew generates both an EUMD and a CCMD.

c. Dependent Failure. A failure event caused by another related event and which occurs simultaneous or nearly simultaneous to the related causing event. In some cases, it may be necessary to present engineering evidence to clearly link the dependent event to the causing event. The Dependent Failure score is also sometimes used for TIRs which document the reoccurrence of an intermittent failure event; usually in those cases separate TIRs were written to document failures which were later determined to be instances of the same intermittent failure.

The scoring IPT may alternatively choose to annotate or revise the TIR describing the initial occurrence to include subsequent related occurrences.

d. Essential Function Failure (EFF). An event that results in the loss of or operationally unacceptable degradation in one or more of the essential functions. Table 1 describes allowable degradation in essential functions and provides additional clarifications with regard to the scoring of the loss/degradation of essential functions. Often, the occurrence of an EFF will not cause mission cessation, but has an significant impact such that it must be repaired prior to the next mission (cannot be deferred).

e. Essential Logistics Demand (ELD). An ELD is recorded for all essential unscheduled maintenance demands and all scheduled maintenance demands that require parts or line replaceable units (LRUs). An ELD is recorded for each part requested or consumed. Thus, it is possible to record more than one ELD per event. This category does not include crew level

PMCS.

f. Essential Unscheduled Maintenance Demand (EUMD). A EUMD is recorded for each event requiring unscheduled maintenance that cannot be deferred until the next scheduled maintenance point at the prescribed level of maintenance. This means that by definition, all

EFFs resulting in a maintenance actions generate EUMDs. Non-EFFs may also result in

EUMDs. Crew safety and potential damage to the system are other key considerations in determining what maintenance is non-deferrable. Repair of fully redundant components, or restoration of a degraded essential function will also result in an EUMD. Note that an EUMD that is corrected and authorized by the crew also generates a CCMD.

g. Non-EFF (NEFF). Failure events which can not be classified as an essential function failure. A Non-EFF may result in loss of non-essential functions, degradation of essential functions not meeting the criteria for an EFF, or minor malfunctions related to either essential or non-essential functions. A Non-EFF will normally generate a Non-Essential Unscheduled

Maintenance Demand (EUMD). It is not always the case that a failure generates an unscheduled maintenance demand.

h. Non-Essential Logistics Demand (NELD). An NELD is recorded for all non-essential unscheduled maintenance demands that require parts or line replaceable units (LRUs). An

NELD is recorded for each part requested or consumed. Thus, it is possible to record more than one NELD per event. This category does not include crew level PMCS.

i. Non-essential Unscheduled Maintenance Demand (NUMD). An NUMD is any unscheduled maintenance action and which can be deferred until the next scheduled maintenance period at the prescribed level of maintenance. This category is used to cover the remaining incidents that require unscheduled maintenance but did not qualify as EUMDs. A NUMD performed by the crew also generates a CCMD.

j. Non-Reliability Failure Event. An event in which no actual failure has occurred. A non-failure event may consist of, but is not limited, to any of the following events:

(1) Preventive Maintenance Checks and Services (PMCS). This includes those procedures defined as PMCS in the system's technical documentation. It does not include those incidents where a part is required. Requirement of a replacement part infers that a component has failed (may qualify as a “failure” and results in corrective action); or that a component has worn out (may be considered as scheduled maintenance). Failures that are discovered during PMCS are normally considered on their own merit, regardless of when they are discovered.

(2) Scheduled Maintenance. This includes those procedures defined as scheduled maintenance in the system's technical documentation. Failures that are discovered during scheduled maintenance are normally considered on their own merit, regardless of when they are discovered.

(3) Routine Operating Procedures. Routine operating procedures performed by the crew and which are prescribed in the user manual. Routine tasks the crew may quickly perform are not charged as failures.

(4) On-Condition Maintenance. Incident in which maintenance is performed to replace a used or worn part/component that has met its life expectancy criteria (i.e., its durability or service life requirement) constitutes “on-condition” maintenance if the part was still functional (functioning) at the time of its replacement. Examples of “on-condition” maintenance include replacement of filters, sieve packs, etc.

k. Other Event or Failure. Events scored thusly will not have a chargeability assigned and will not be included in the overall reliability and maintainability evaluations of the system.

These events may include pre-test checkout/inspections, equipment modifications, test-peculiar events, test-directed abuse (e.g. test directed stresses beyond the performance limit of the system), unrelated damage, and other non-R&M related events. Further expansion this category follows:

(1) Pre-test/Post-test checkout. TIRs describing the performance of pre-test or post-test inspections or checkouts, and events observed during pre-test inspection or other pre-test activities. The test plan must specify the duration of the pre-test period in order to determine when the pre-test has ended. Events occurring after the expiration of the pre-test duration will be scored on their own merits. Events occurring after the conclusion of the test are also scored in this category. Post-test events discovered after the conclusion of the test but which occurred during the test will be scored on their own merit.

(2) Equipment modification. All maintenance actions involved in the installation of hardware kits or incorporation of redesigned components. If the replaced component was not functioning at the time of its replacement with the modification, the event will be scored on its own merit. The maintenance time will be estimated based on the time to restore the system to its original condition. Subsequent events related to the malfunction will be scored on their own merit.

(3) Test peculiar. Events caused by equipment that is not part of the system being tested or people not acting as test players (crew or maintenance personnel). Engineering evaluations to analyze the cause of the malfunctions, as well as any malfunctions and/or maintenance efforts caused by the engineering evaluation. Events related to test peculiar diagnostic equipment used in lieu of the diagnostic equipment which will be fielded are scored on their own merits.

(4) Non-R&M Oriented. Events for which a test incident report might be initiated by the test activity, but which are not events used in R&M computations. Examples include suggested improvements, reports on inadequate test procedure, unusable or unacceptable replacement parts which were discovered prior to or during installation, the systems consistent inability to meet performance specifications even though no actual malfunction has occurred, test schedule delays, and suggested human factors improvements.

Recommended changes to the system support package not related to a specific event, and damage caused by natural phenomena (lightning, earthquakes, etc) and other influences that are beyond the control of the operational elements of the system are also covered here.

(5) 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. Events attributable to misuse will not be scored against the system, as they provide no viable indication of its ability or inability to function reliably in the operational environment.

(6) Performance Limitation. This includes those incidents which report the inability of the system to meet a specified performance criterion even though no malfunction/failure has occurred.

(7) Unrelated Damage. This category includes damage caused by natural phenomena

(e.g. lightning, earthquakes, etc.) and other influences that are beyond the control of the operational elements of the system. Accidents caused by hardware malfunction or other operational elements of the system (crew, maintainers, etc.) are charged on their own merit.

(8) Administrative. This category includes reports of administrative details of the test, such as the beginning or end of reliability testing, etc.

l. Rapidly Recoverable Event (RRE).

(1) An incident which meets the conditions of an EFF, but which can be quickly rectified using an authorized operator action/procedure using only normally available tools and equipment is scored as an RRE. This category is intended to cover those infrequent incidents which can be quickly corrected without significant loss of function. An RRE must be a trained recovery activity (e.g., restarting the function/software module, rebooting the system, cycling power), or be readily apparent to the operator (e.g., reattaching a cable). If it is apparent that there is a systemic problem which is being consistently scored as an RRE, the scoring body may decide to score them either individually or as a group as an EFF or SA. At the discretion of RAM Scoring Committee members (based on input from test personnel and/or Subject Matter Experts), frequently recurring failures of a particular type (or an excessively high frequency of failures in general) that cumulatively consume an excessive amount of mission time for execution of crew level corrective maintenance may result in a higher level of failure classification (even an EFF or SA) being assigned to address/convey the overall cumulative impact of the failures (in the event that the adverse impact on operations is great enough).

(2) Fifteen minutes is allowed for the conduct of any required troubleshooting and authorized corrective operator-level maintenance actions to restore loss of an essential function.

(3) The frequency of recurring operator correctable incidents (initiated to address the loss or degradation of an Essential Function) may prompt the RAM Scoring Committee to ultimately classify the cumulative effect of such incidents as an SA, if it is obvious that the vehicle’s ability to successfully complete the mission has been substantially degraded or compromised to a critical extent. Accordingly, three recurring RREs executed during an individual mission are subject to being collectively scored as an EFF or SA.

m. Scheduled Maintenance Demand (SMD). This is a maintenance action that is part of a program of preventive maintenance and is not attributable to an equipment failure. To qualify as an SMD, an event must meet the necessary intervals, usage requirements, conditions, and durability requirements defined in applicable system technical documentation (i.e. technical manuals).

n. System Abort (SA). A failure event that results in the loss or degradation of an essential function(s) that renders the system unable to enter service or causes immediate removal from service, deadlines the platform, or makes it non-mission capable (a SA reduces its utility to the point that it is deemed ineffective/unsafe in its primary role). System abort also includes those malfunctions that create a personal injury related Category 1 (catastrophic) or 2 (critical) hazard as defined in MIL-STD-882E (see Table 3). By definition, all SAs are also EFFs and are annotated as “SA/EFF”. An SA may result in a “Not Mission Capable” status under wartime conditions or reduces its utility to the point that it is deemed ineffective/unsafe. By definition all

SAs are also EFFs. Therefore, MTBEFF is calculated including System Aborts (SA), and EFF events.