Modifications

Question 1

What is a modification?

Answer 1

An approved in-service design change to an aircraft or associated equipment that arises due to operational requirements or to improve equipment.

Question 2

What is the purpose of a modification?

Answer 2

They are used to improve safety, op efficiency, capability, reliability, maintainability and to ease production or overcome obsolescence.

Question 3

What are the different types of modification?

Answer 3

Design organisation Modification

Service Modification

Cover Modification

Urgent operational modifications

Question 4

Design organisation Modification

Answer 4

During the life of a project, there are likely to be changes required to the build standard of an Air

System (and related products, parts, appliances or Air Launched Weapons (ALW)).

• The design and embodiment of modifications is to be actively managed.
• The primary route to embody this change is through Design Modification (DM) action, which is to be initiated by the Project Team (PT).
• Changes made are on a permanent basis.
• The modification is provided with the applicable technical instruction and spares/tooling packages.

Question 5

Service Modification

Answer 5

• In certain circumstances the Delivery Team (DT) may use the Service Modification (SM) process

to change the design of their military Air System (or related products, parts and appliances).

• This may be in preference to the Design Modification (DM) route if it is of an urgent, special or short-term nature.
• Although it is not the preferred route, a SM provides the DT with the flexibility to embody the change.
• DT retains control of the Modification until it is either superseded or it is removed. - SM’s must be trailed before use.
• SM’s are deemed to take less than 50 man hours to embody.
• Increases capability
• Improves Maintainability/availability
• An SM may be cancelled whenever is purpose is fulfilled, it is superseded or the original requirement no longer exists.

Question 6

Cover Modification

Answer 6

• Used to make a Service Modification into a permanent change with the Design Authority.
• Design Authority will take ownership of the modification and provide a spares contract.
• The Design Authority can choose to re-design the Modification to meet design standards if the

current SM does not meet that standard.
- The Aircraft maintenance manual will be updated to show both pre and post Service

Modification standard. This helps to avoid confusion and potential airworthiness problems.

Question 7

Urgent operational modifications

Answer 7

• Used to make a Service Modification into a permanent change with the Design Authority.
• Design Authority will take ownership of the modification and provide a spares contract.
• The Design Authority can choose to re-design the Modification to meet design standards if the

current SM does not meet that standard.
- The Aircraft maintenance manual will be updated to show both pre and post Service

Modification standard. This helps to avoid confusion and potential airworthiness problems.

Question 8

Urgent operational modifications

Answer 8

• Used when equipment is required urgently to fill a void in operational capability.
• Equipment used will already be developed and available from industry or another approved military supplier.
• A short life modification, funding and support isn’t expected to exceed 12 months.
• If the modification is a success and proven to be value, long term contracts will be adopted.

Question 9

Why use SM instead of DM?

Answer 9

The decision to proceed with a SM in preference to a DM will be a result of time and cost factors rather than technical reasons. Prior to using the SM route though, the PT is to fully consider the through life costs of supporting the modification.

Question 10

Who is in charge of modification embodiment programmes?

Answer 10

ACOS (CSAV) and the PT
Engineers are responsible for accounting, assembling and stowing of role equipment

Question 11

What is a modification proposal?

Answer 11

It is where the requirement for a MOD has been identified and then ‘proposed’ for assessment by the DA (if applicable), front line command, PT and operational and engineering staffs.
If the proposal is pursued, the PT manages the development of the mod using the appropriate procedures, (there are three procedures, normal, urgent and operational emergency).

You can use the joint modification service for info on submitting a MOD proposal form and the track before a potential embodiment

Question 12

Where do modification proposals usually originate?

Answer 12

Continued development to meet the specification
Faults in service
New operational roles or the need to improve the effectiveness of existing roles The need to improve reliability, maintainability or cost-effectiveness Obsolescence of items or equipment

Question 13

Do modification proposals follow the same procedures in normal, urgent and op emergency?

Answer 13

Yes, the normal procedures are followed as far as possible but in an extremely compressed time-scale. However in exceptional circumstances, a DM for example may use SM procedures.

Question 14

What is a modification standards table?

Answer 14

They were formally used to identify mod states at aircraft build, mods that should be embodied in op environments, mods with riders etc. but are no longer extant.
The AIL in the front of the relevant publication should now be used instead.

Question 15

Who raises the requirement for a Design Modification and how are they then normally processed?

Answer 15

The PT will identify the requirement for a DM an request the DA input
The requirement will be specified on a Modification Proposal Form
The DA will produce a draft DM leaflet and forward it to the PT for technical editing
PT will then edit and review edited version (seeking advice from Sqn/FLC if necessary) If acceptable, the PT returns the DM leaflet to the DA who then embody the mod
The Topic 2 is amended

Question 16

Who raises the requirement for a Service Modification and how are they normally processed?

Answer 16

• The Sqn/FLC engineers/aircrew or safety issues will raise the requirement for a mod
• A SM proposal is then made
• The PT will look for a feasible solution (costs, equipment availability, resources etc.) and into acquiring funding
• The SM proposal is accepted
• Initiation meeting takes place to find a solution, plan trials and produce an initiation certificate
• The SM is developed (designing of the SM, drafting of a SM leaflet, safety case put forward)
• A trials programme is installed encompassing aircrew and engineering training requirements
• Clearance Meeting held, aircraft cleared for trials (ground and flight), draft SM leaflet approved
• Flight Trials are carried out, evidence provided for the RTS
• Mod is ‘proof installed’; any updates to design are looked at
• Configuration control is carried out, SM leaflet is issued, ADS updated, RTS is granted
• Mod is embodied

Question 17

Wrt mod proposals, what is an urgent operational requirement?

Answer 17

Used to procure new equipment and put it to operational use very quickly.
Is applied when rapid purchase of already developed ‘off-the-shelf’ equipment is required from industry, military stock or friendly nations.

Question 18

Wrt mod proposals, what is an operational emergency staff requirement?

Answer 18

Used to urgently develop and production of new equipment to meet an essential operational requirement.
They are processed on a priority basis in relation to normal staff requirements.

Question 19

How are modifications promulgated?

Answer 19

• DA modifications are contained within the ADS (Topic 2)
• Topic 2 (N/A/R) – service modifications for specific aircraft types, controlled by the PT
• MOD leaflets – issued for all modifications where service embodiment is required, archaic MOD leaflets are kept in the AEOW office
• Information leaflets – issued when users are not required to embody the modification but need to know its effect, kept in AEOW office
• GOLDesp – when a MOD is due embodiment it is added to the maintenance activities forecast

Question 20

What information does the Topic 2 contain?

Answer 20

1. Mod list for each aircraft system
2. Details the effect on mass and moment, operation and handling, support equipment for each mod
3. Materials required
4. Procedure for embodiment
5. Compliance and recording action

Question 21

What is meant by the coding of modifications?

Answer 21

The coding or classification of mods indicates the urgency and application of the modification and who is to embody it.
A modification that is to be embodied by industry are classified by letters and by services are by number. Sometimes a mod can be classified as both.

Question 22

What is meant by the term, ‘service application’?

Answer 22

Aircraft that are in service at forward facilities and in modernisation/depth packages at Fleetlands etc.

Class 1 – mod is essential for safety. Aircraft may be AOG until mod embodied
Class 2 – high priority. Without embodiment, serious limitations and reduced capability

Class 3 – priority. Embodiment of the mod is adjudged to have a gain in operational efficiency, reliability, economy of operation in comparison to the cost and effort of retrospective embodiment

Class 4 – mods that are normally embodied on replacement of defective parts, when all spares to original specifications have been used. E.g. HEIU screws.

Class 0 – mods that are not embodied in service but could affect the interchange ability of service spares

SOO – mods that achieve a limited specified objective. Embodied on a limited number of aircraft/equipment

Question 23

What is meant by the term, ‘contractor application’?

Answer 23

Aircraft and equipment that are in production or being overhauled by the Contractor Repair Organisation (CRO) or Fleetlands etc.
Class AA – mods essential for initial release of a new type/mark of aircraft that must be embodied prior to the delivery to service.

Classes A – D, - same as the service priorities, with A being of highest priority

Question 24

What is a mod set?

Answer 24

Equipment supplied by the design authority or contractor to complete the Modification.

• Items are manufactured by the contractor specifically for the job other than aircraft general stores which will be added to the Mod Set via service stores.

(football boots)

Question 25

What is a mod kit?

Answer 25

## Footnote A mod set and other service supply items, which is then assembled by the service, before issue for embodiment (mods control) Or An aggregation of service supply items required for a modification, but not requiring a modification set Everything you need to fit the modification

Question 26

What are riders and notes?

Answer 26

## Footnote Riders and notes are used to amplify the modification classification code. Riders specify to what extent a service modification should be carried out. i.e. how, when and by whom it should be conducted. Notes detail any other special requirements you need to be aware of prior to embodying the mod.

Question 27

Name some examples of riders

Answer 27

## Footnote Working party – mod is to be embodied by a contractor working party or service mod party On replacement/removal of unmodified item – on first occasion non-mod item is removed/replaced Satisfied by – followed by a SM or S(TI) number, if that instruction/work has been carried out the mod leaflet has been satisfied Superseding – followed by a SM or S(TI) number, the TI/SM has not satisfied the work requirement and so another mod leaflet has been issued On failure – Mod is embodied on failure of said component

Question 28

Name some examples of notes

Answer 28

* NCP (no contractor parts) – if no parts are needed for the task or if parts are needed, they are to be obtained from service sources * RPO (record purposes only) – used for the initiation of design changes or recording information, the mod leaflet does not require service action * ROP (reverse order of priority) – mod sets are issued for service embodiment prior to issue to the contractor

Question 29

How is the embodiment of a modification recorded?

Answer 29

## Footnote Embodiment recorded in the MF700C Recorded as completed on GOLDesp Weight and Moment updated on GOLDesp and printout added to the MF700C sect 4 Modification plates on the component itself Part number change of the component on the physical structure on GOLDesp

Question 30

## Footnote What happens to a pre-mod component in stores?

Answer 30

## Footnote In the event of the mod classification being a 1 or AA, then the pre-mod item should be modified or removed from service. In other instances, where the service needs to retain both modified and pre-mod items, the PT is to ensure there are adequate spares. E.g. NVG equipment

Question 31

## Footnote How can the mod state of an item be identified?

Answer 31

## Footnote On GOLDesp, you can check the modification state of a component If you know the modification number, you can search on GOLDesp to see if it is has been embodied but isn’t wram tracked The part number of the component Mod plates on the component which are altered as the mod state changes Sometimes the mod state is written on the component Aircraft Y list

Question 32

What is an aircraft Y list?

Answer 32

## Footnote Prepared by the DA at request of the PT, known as the ‘Modification Standard Number Sea King Mk 5 Y/1’ The Y list is a list of all the modifications to that aircraft leading to its mark, known as the ‘Modification Standard Number Sea King Mk 5 Y/1’ The number denotes which mod standard the aircraft is at, at build the standard would be Y/1, and it would list all the modifications incorporated during build, e.g. any design flaws Y/2 would list all the additional mods that have been embodied since the standard Y/1 Therefore Y lists create a standard at which aircraft should be at The Y list standard number should be stamped or scribed on the mod plates of components Striking through say the number 1 of the mod plate would signify that the component was at Y/1 standard ‘Y-lists are modification lists which must be embodied in the equipment during production and are prepared to simplify the recording of modifications. However, Y-lists serial numbers may be quoted with plus for embodied mods and minus for those not embodied’ RA 5307

Question 33

## Footnote What is meant by configuration management wrt modifications?

Answer 33

## Footnote A design must be controlled from the perspective of configuration control and maintenance of design records in order to ensure a smooth lead-in to certification of the design. In order to do this a configuration management plan (CMP) is drawn up and agreed with the PT at commencement of the contract. The plan is subject to regular reviews throughout the design process.

Question 34

Why is configuration management important?

Answer 34

The DA are able to control the design process through the CMP and remain flexible to make any design changes at an early stage, thus being more cost effective and efficient. The DA will set up a committee as part of the CMP who will be able to; * Prepare and maintain a configuration status record * Control design changes * Record and control the standard of design to be manufactured * Record the reason for its decisions * Make available the reasons for its decisions

Question 35

What are the modification categories?