Issue raised against: aviation_maintenance

The mapping of Maintenance activity is not done in accordance with the intended usage of the PLCS entiities Activity and Activity_actual. The Activity entity shall deal with the information related to the planned work, whereas the Activity_actual shall deal with the information recored throughout the performance of an activity. The mapping in Figure 5 does not show this distinction. The mapping of the maintenence activity should include both Activity, Activity_actual and Activity_happening entities. There should probably be two "assigning_activity" templates used, one for the relationship between the Activity (i.e. the planned) and one for the Activity_actual (i.e. the recorded).

The assignments of "assigning_time" representing the planned start , and planned end shall be assigned to the Activity entity. So should also the "assigning_process_property" representing expected man hours, and the "assigning_identification" that identifies the Maintenance activity.

Comment: (Rob Bodington 07-03-28)

I think that you were reviewing an out of date copy. The maintenance activity is represented by the template representing_work_done. This contains an Activity_actual related to an activity by Activity_happening. The related activity is the Directed_activity which is part of representing_work_order.

The assignments of properties, people etc, are all assigned to the Actual_activity in the template representing_work_done

The mapping of the link to a predefined maintenance task (choosen_method) in figure 5 should relate to a Task_method_version, instead of a Activity_method. This would allow for versions of Maintenance Tasks. (see DEX 3, TAsk set).

Comment: (Rob Bodington 07-03-28)
There was an agreement that the a work order and typical activity would be described by an activity_method which is them related to a task - if appropriate, by an Activity_method_realization. That way the DEX does not enforce the use of Task - which some business processes do not support

The mapping of NSN in figure 5 is not in line with other mappings done (e.g.) TLSS. There has been a discussion on representing NATO Stock Items as Resource_items, and not assign the NSN directly to the Part.

Comment: (Rob Bodington 07-03-28)
We are not referring to a NATO Stock Item. We are saying that this part (or product as realized) has been classified by this NSN number. It is a classification. We are not referring to a resource item. My understanding was that was the TLSS approach as well.

We should not use the Resource_as_realized_resource_item.quantity attribute, but use a property assignment instead. (figure 14)

Comment: (Rob Bodington 07-04-18)
Why?

Why is the NSN assigned to a Product_as_realized. A product as realized is always related to a Part, which in turn..... Also see issue GYL-5

Comment: (Rob Bodington 07-03-28)
See GYL-5

How do we represent the relationship between LCN number (breakdown) and part number.

PLCS representation sections should be amended to reflect the style of Representing state of a reportable item

Comment: (Trisha Rollo 2007-04-16)
Done: Representing a message Representing a maintenance work order Representing reportable item maintenance activity Representing a reportable item Representing properties on a reportable item Representing replaced parts Representing installation/removal position on an aircraft Representing a reportable item usage activity Representing reportable item location Representing related components Representing change of Part Number, Serial Number, and NSN Representing Inventory Gain and Loss Awaiting: Representing Task extensions

2 Related DEXs ......Product operational information. The procedures ........ This full stop seems wrong. Possibly a colon?

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3 Scope ......items life ........ I think we also need health. eg "pressure" in a tyre; max pressure during sortie for an engine stage.

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4 Business Process ......Removal and evacuation -> Repair/Overhaul ........ These seem to be reasons for removing an item, but not activities in themselves. I do not see how they differ from "Removal".

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5 Inventory activities .......Gains To Inventory -> Loss to inventory ........ Are these part of the AM DEX, or are they covered by DEX 8? If the purpose is to say "this asset is now mine", and "this asset is no longer mine" then it probably is part of this DEX. My intent for this when discussing LITS data was for Inventory Gain to provide all the information about the asset. That is probably the purpose of DEX 8 for status, and this DEX for history of maintenance.

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6 Information Model Product usage information .... Possibly include "operating environment"?

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6 Information Model Product usage .... I think that health is required here. eg "maximum operating temperature" Health is a measure that must be within a given range; may be one of "between A and B"; "less than A" "more than A".

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6 Information Model Product usage Serviceability change This activity reports when a serviceable, uninstalled item .... Also applies to aircraft.

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6 Information Model Product usage Serviceability change .....rejection .... I'm not sure about the term "rejection". Examples I might use are "maintenance has become due" and "an operator has identified a fault".

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6 Information Model Removal of Serviceable Reportable Items for Controlled Exchange ............ Should this state that the installation is reported as a separate, related, Installation activity?

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6 Information Model Lifing extension ...........date........ It is not "date"; it is the life value

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6 Information Model Lifing extension ...........tasks........ It is not "tasks" in general; it is "maintenance activity is due"; The maintenance activity may be "discard the part" for finite life.

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6 Information Model Maintenance ..........approved........ Is it just "approval" or is it other task life-cycle activities, such as recording effort; recording task completion; recording task coordination? In general, I thing it is recording management information about the maintenance activity whereas the other items are recording what happened to the asset.

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6 Information Model Loss to inventory ..........has be decommissioned ........ typo: "been"

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6 Information Model Maintenance work order .......... I had previously said that Sapphire allows multiple "asisings" ("observations"/"symptoms") on a work order.. I am advised that this is incorrect. Sapphire has a concept off "work package", which is a group of Work Orders to be addressed together (eg grouped by trade) and allocated to one person to "manage". The allocation of work orders to a work package is a manual process in Sapphire; A work order must be part of a Work Package for Sapphire to allow work to be recorded. I have not seen anything in the DEX that would allow "Work packages" to be passed.

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7 Aviation Maintenance - Implementation details .......... It is a little confusing in this section that the template names do not reflect the names in the diagram. eg: "Template: #1 representing_product_as_realized " rather than "Template: #1 Reportable Item".

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9 Business information .....required, see: Section: . ..... Missing reference.

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Template #1 (Figure 5): .....Local_time........... This says "local time", but subsequent commet ("offset") suggests that time should be UTC, not local.

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ap239_id_class_name: .....the message (Message) of the message............ No make sense to me

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Figure 6 — UML model representing a maintenance work order Maintenance_activity ............ Should there be something related to this identifying who did it; resources used, etc, or does that come later?

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Figure 6 — UML model representing a maintenance work order Repair_overhaul ............ Does this also cover the case where an asset is removed and returned to stores? I belive it is "any removal where there is no immediate plan to fit either to the same position or to another position or end-item.". As such I think the name is misleading.

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10 PLCS representation ............ feel that these sections would be better organised with the diagram before the description. It took me a while to realise that the template numbers were referring to the later diagram rather than to an earlier diagram.

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10 PLCS representation .......Reportable_item.NSN NATO Stock Number of the reportable item ..... This may be a "domestic" code

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10 PLCS representation .......Reportable_item.supplier_code ...... NOTE The supply code ..... "NOTE The supplier code"

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11 Representing a reportable item 12 PLCS representation ..... This seems to say that the "description" is against a part spec (PLCS "part"). Also need description against the specific part, as Sapphire allows specific comments.

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11 Representing a reportable item 12 PLCS representation ....., it is advisable to use the template representing_product_as_realized.......... Surely the DEX should say one or the other, or if they are equivalent (which they don't appear to be to me), then show the digram with the template included.

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13 Representing properties on a reportable item Reportable_item_property.value_type ....., sortie.......... Does this mean that "sortie" would be used for a health measurement, such as "presure"

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14 PLCS representation.......... This does not seem to allow for calendar-based items. Calendar-based items should give dates for "last occurred" or "next occurs", and should not (in my opinion) give"how long since" or "how long until" values. The "how long" approach requires calculation on the receiving side to provide "current" data. eg receipt of '10 days to go' needs calculation to show the true "time to go" if, for example, the data were received 3 days ago.

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14 PLCS representation.......... It seems to me that there are three distinct cases that need to be defined: a) Life values, where numerics and deltas are required, b) "sortie" (health/consumption) values, where numeric and "current" is required; no deltas. c) Calendar-based values, where absolute date/times are required (possibly with deltas?). Since there are different required/optional sets here, it seems to me that these should be modeled separately.

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14 PLCS representation.......... "Increment" is shown as required. I believe it has no meaning when a "sortie" metric is being reported.

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14 PLCS representation..........it is advisable to use the template............... Similar comment to above

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16 Business information........., see: Section: . ............... Missing reference.

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16 Business information........., spare ............... Does this mean "serialised"?.

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17 PLCS representation........... The UML shows serial number as an attribute, but I see no representation of this in PLCS.

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17 PLCS representation.........out of scope ............... Even if in scope, what is actually used may differ from the spec in the task. eg some parts may be "on condition" rather than "always".

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17 PLCS representation..........it is advisable to use the template............... as above

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19 Business information......... The section heading is Representing installation/removal position on an aircraft, but the section is about history and does not reference a position in any way. There may be several positions in a parent to which a part can be fitted, eg a blade on a rotor head. The whole section is about "what" and "when" and "what to", but not "where". "Where" is needed too (PAC/SAC in LITS).

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20 PLCS representation......... This seems to bear little relationship to teh UML

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20 PLCS representation.........The position of the reportable item on the aircraft is represented in the Aviation maintenance DEX by referring to the next higher assembly and the aircraft (or end item) from which the reportable item is removed/installed. ................ As above, I believe this to be inadequate.

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20 PLCS representation.........The serial number which identifies the specific reportable item, and the NSN ................ Also need part no and CAGE code.

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20 PLCS representation.........The serial number which identifies the specific reportable item, and the NSEach date when the installation / removal occurs is represented ................ I believe a statement is needed on what this means when part A is fitted to part B and then part B is fitted to a/c C and part A is subsequently removed.

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21 Representing a reportable item usage activity........... Usage_................. The names used here do not match the UML diagram

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21 Representing a reportable item usage activity........... template #2................. This is shown as optional; I would have thought mandatory, unless it is intended to obtain the date/time from the "sortie" by reference to something in the "sortie" record for the end item. If this latter is the case, then it should be explained.

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21 Representing a reportable item usage activity........... Usage_profile.start_time ................ This does not appear to be represented in the PLCS.

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22 PLCS representation................ I'm not sure what is intended to be represented here. Is it the sortie, or is it the usage from the sortie, or both? I would have expected the sortie and the usage from the sortie to be shown separately.

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Figure 20 —................ What does the bit about a business DEX mean?

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Figure 20 — UML................ Symptoms do not necessarily come from usage. They can come from inspection or "accident" such as "it fell off the lorry". Can this be represented?

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Figure 20 — ........not operating correctly................. Not quite. It means that the item is considered to have a defect; investigation may or may not find this to be true.# For example, with electronic kut it is common practice to replace several items without determining which are faulty, on the basis that getting the aircraft serviceable is important; determining which iteactually caused the fault can be done in slower time.

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Figure 20 — ........UML Class definitions................. I don't see anything in here that covers "Asset Condition", which is a sub-classification of "Unserviceable" for assets, such as test, repair, scrap

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Figure 20 — ........Fault -> requirements ................ I think this should be "specification".

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Figure 20 — ........Fault_status.deferred_to..........This could be a date, ................ There is a specific "deferred to date" attribute, so how is this expected to be used? I would guess that it would be better to keep it as a numeric life metric plus metric value. Although reading further, it looks like this is just the value, with the metric being identified in deferred_to_metric

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Figure 20 — ........Symptom.........performance ................ I'm not sure "performance" is quite right, but it is difficult to think of another term. Possibly "usability".

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Figure 20 — ........Symptom.flight_safetey_hazard ................. affect ................ "effect"

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Figure 20 — ........Symptom.whenhow_source .................. who ................ Can also be "discovered" by monitoring systems such as HUMS (Heath and Usage Monitoring System)

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Figure 20 — ........Servicability_status.organization ............. Serviceability Change ................ Clarity: There are two changes: Into state; Out of State. I believe it is "at the start date".

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Figure 22 — ................ This suggests that template #3 is mandatory. I believe it to be optional.

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Figure 22 — ................ Template #8 is referenced from text, but I don't see it in the diagram.

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24 PLCS representation.............. Symptoms ................ Should there be some description of #13 and #16?

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24 PLCS representation.............. Symptoms ........known........ I think a different word or phrase is needed here. A fault is "kown" once it occurs. It is possibly "common" faults or "faults forseen by the manufacturer"

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24 PLCS representation.............. Symptoms .......#18....... I think this should be #12.

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24 PLCS representation.............. Faults and States .......#7....... Believe should be #22

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24 PLCS representation.............. This should not be confused with the code that is used to identify and the state type - these are represented by reference data and are set as parameters in the template. ....... I don't understand this bit.

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24 PLCS representation.............. first by an assessed state, then once the fault has been confirmed though measurement for example, by an asserted state. ....... Is this required, or can there be just an asserted state?

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24 PLCS representation.............. In addition many applications . ....... Missing word(s)?

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24 PLCS representation.............. , in which case the state is identified by the template #8 and #4 assigning_identification. . ....... Are you saying that in general the state may be represented in one of two ways a) By reference to state definition; b) by explicit value?

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24 PLCS representation.............. The dates when the fault was identified and rectified ....... I'm unclear what the meaning of these are, in particular start and end of "assessed" and any relationship to start of "asserted".

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Figure 24 .............. What is the "geographical feedback report"?.

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26 Business information.............Location_history.status_at_exchange.............. I'm not entirely sure why this is needed. I guess it is what LITS records, for some reason, rather than determining it when required. I do recall that EPMS used to give conflicting data when different histories were compared, because it stored "A when B chganged" and "B whenm A changed" history, but treated each separately so that when both changed at the same time it would give something strange. Is there the possibility that by tagging "value of A when B changed" could give different results to a query on the underlying data of the form "what was the value of A when B changed?"?

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27 PLCS representation.............#1 representing_work_done and described in detail in Section: .............. I believe that location change is not part of maintenance work. It is the result of a decision made outside the maintenance arena.

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27 PLCS representation.............asserted state .............. Items removed from aircraft and returned for repair probably have an assessed state but not an asserted state (maintainer believes them to be faulty, but this is not confirmed until assessed in the maintenance bay).

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29 Business information.............. I don't understand what this message is forhow it will be used.

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Figure 27 — .............. This seems to say that NSN is required to identify a product_as_realized. NSN is optional.

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32 Business information........... It is not only during repair/overhaul. It may be that the exact part fitted is not known, so is allocated a "temporary" identifier. When the part is eventually accessed or removed for some reason, the true identitity may be revealed. The true identifier may then be set by a change of part/serial number. Sapphire provides a function to allocate part numbers and serial numbers to parts that are known to be fitted but exact details are not known. This may also result in a change of CAGE code. but it looks like this may be catered for as the "Part" defines CAGE code. BUT does CAGE code need to be identified explicitly in th ediagram?

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33 PLCS representation The UID ........ I don't understand what "UID" represents in the real world.

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36 Business information ........ Tasks may also be given negative extesions, for example to reflect stress or damage caused in unusual circumstances.

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36 Business information ........particular fault occurs,.................... These cannot be extended because extensions are against metrics. These tasks may be deferred.

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36 Business information ........delayed.................... Tasks may also be given negative extesions, for example to reflect stress or damage caused in unusual circumstances

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36 Business information ........Task_execution_trigger .................... Task Execution is conditional. For example, a task may be applicable only in certain operating conditions, or when part is fitted in a particular position. Therefore probably need to have an "active" attribute to specify whether or not the task will be triggered when the limit is reached (whether or not the task is applicable in the current environment). I believe this is needed so that queries don't suggest that a task has not been triggered when it is not applicable.

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36 Business information ........Task_extension ...... Task_extension.extended_percentage_of_interval .....The percentage .................... I believe that this should be cumulative. The cumulative percentage is needed because that is what determines the overall effect of the extension. Possibly two attributes needed: delta and cumulative. Looking further, it looks like "required" items are deltas for this instance and "extended" are cumulatives. A bit more explanation might be useful.

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36 Business information ........Task_extension.max_permissible_extension .......... The maximum permissible extension allowed for a Standard Maintenance Task minus the total percentage extension assigned. .................... I'm not sure about this one. The name seems wrong (it should be something like "permissible_extension_remaining")

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37 PLCS representation .............. I think that this one is beyond me in my current state of knowledge and tiredness, but a couple of observations follow!

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37 PLCS representation ..............The Condition, Condition_assignment and Condition_parameter are all instantiated by the template #4 assigning_condition ................... This seems to be saying that the conditions for the task execution trigger are being sent. Is that coorect, and if so, then the question is "should we send the conditions?". Or is this representing the fact that a condition has changed? It seems to me thatthe only condition is "metric reaches threshold" and we are just passing information about a change to the threshold and not about the condition itself.

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37 PLCS representation ..............#5 representing_numeric_property ................... How are date/time limits represented?

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Comment: (Rob Bodington 07-03-28)
The DEX now uses the latest templates

The text under "Reportable_activity.reporting_organization" and "Reportable_activity.reporting_person" should probably refer to the reporting organization/person instead of as now, the one who undertook the activity.

Comment: (Rob Bodington 07-03-30)
Corrected

The mapping of Reportable_item.previous_part_numbers and Reportable_item.previous_serial_numbers in figure 10 should use Dated_effectivity instead of "assigning_time" representing start/end dates.

Comment: (Rob Bodington 07-04-18)
Corrected

Reportable_item_property is probably not a good name, since its usage is limited to recorded values. Suggestion rename to e.g "Reportable_item_recorded_property" (or measured or...)

Comment: (Rob Bodington 07-03-30)
It is used as a value for a task trigger as well. The intent is to provide a scoping model rather than a detailed model

Figure 18 (EXPRESS_G diagram for representing a usage activity) shoud be reworked in accordance with the issue GYL-1.

Comment: (Rob Bodington 07-03-30)
The diagram has been redrawn to use the template reporting_product_usage

Figure 26 (EXPRESS_G diagram for new PN, SN and NSN) should use Dated_effectivity instead of "assigning_time" representing start/end dates (Also see issue GYL-4).

Comment: (Rob Bodington 07-04-18)
Corrected

Figure 15 - note needs adding to figure about the use of template (similar to that in figure 11).

Comment: (Trisha Rollo 2007-04-11)
Figure 15 has been amended to add note

Maintenance_work_order.maintenance_organization is the “Maintenance Organization raising the Maintenance Work Order” . This also contradicts the PLCS representation statement which indicates the organization conducting the maintenance.

Comment: (Trisha Rollo 2007-04-11)
work order requires both organizations, amended

Fig 9 should show an approval. There should also be a template table and text

Comment: (Trisha Rollo 2007-04-11)
Figure 9, template and text amended

How is an unknown or not required version number identified

Comment: (Rob Bodington 07-04-18)
This is described in the capability representing part

Representing a reportable item/PLCS representation /Part – referencing capability rather than template: (For details of identification, see the capability: C001: assigning_identifiers and the template: C001: assigning_identifiers). Should state (For details of identification, see the capability: C001: assigning_identifiers and the template: assigning_identification).

Comment: (Trisha Rollo 2007-04-12)
text amended

Representing a reportable item / Figure 11 should show both Manufacturing and owning organizations of the part. PLCS representation needs to reflect this also

Comment: (Trisha Rollo 2007-04-11)
Figure 11, template table and text amended

Figure 13 is wrong – it is missing view_defn_context . PLCS representation needs to reflect that this would be part of the template representing_product_as_realized.

Comment: (Trisha Rollo 2007-04-11)
Figure 13 and PLCS representation amended

Representing properties on a reportable item/PLCS representation words explaining property_value_relationship or time, organization and value type required

Comment: (Trisha Rollo 2007-04-11)
PLCS representation amended

Figures 7,11,13,15,17,19,25,27 and 29.need references to other figures completing

Comment: (Rob Bodington 07-04-18)
Corrected

Representing replaced parts – need to clarify what is the difference between this and intstalling parts - trackable versus non trackable STItems.

Comment: (Trisha Rollo 2007-04-13)
PLCS representation amended

Maintenance work order PLCS. The PLCS seems to contradict the figure. In the figure the assigning_activity relates the r_p_a_r for the end item to the r_w_o, and not the r_p_a_r for the reportable item.

Comment: (Rob Bodington 07-04-18)
Corrected.

The template representing message had changed producing errors

Comment: (Trisha Rollo 07-06-15)
amended to reflect updated template.