Asia e University

Malaysia institute 0f logistics

Intermediate logistics officer course

(Executive bachelor in logistics management)

Assignment for logistics Management

Assignment no2

How does maintenance planning affect

operational spending: supply support and

facility?

Ltcdr hamed Alghafri

Royal Navy of Oman

Date:23 MAY 2011

Contents

INTRODUCTION..............................................................................................................2

Spare part classification...................................................................................................3

Repair cycle.....................................................................................................................4

Repair of repairables....................................................................................................4

Replenishment..............................................................................................................5

Performance metrics....................................................................................................5

Military operations spending and maintenance................................................................5

References.......................................................................................................................7

1

INTRODUCTION

The planned maintenance system is one of the important elements of the integrated

logistics support (ILS) which is an integrated approach to the management of logistic

disciplines in the military, similar to commercial product support or customer service

organizations ILS has been categorized into the following elements:

Reliability engineering, Maintainability engineering and Maintenance (preventive,

predictive and corrective) Planning

Supply (Spare part) Support.

Support and Test Equipment/Equipment Support

Manpower and Personnel

Training and Training Support

Technical Data / Publications

Computer Resources Support

Facilities Packaging, Handling, Storage, and Transportation (PHS&T)1.

1Integrated logistics supporthttp://en.wikipedia.org/wiki/Integrated_logistics_support

2

Aim

The aim of this paper is to highlight the effect of maintenance planning on the military

operation spending in the term of supply support.

Scope

This paper will concentrate on spare part as an item of inventory that is used for the

repair or replacement of failed parts.

Spare part classification

In logistics, spare parts can be broadly classified into two groups, repairables and

consumables. Repairable parts are parts that are deemed worthy of repair, usually by

virtue of economic consideration of their repair cost. Parts that are not repairable, are

considered consumable parts. Consumable parts are usually scrapped, or

"condemned", when they are found to have failed2.

Economically, there is a tradeoff between the cost of ordering a replacement part and

the cost of repairing a failed part.

When the cost of repair becomes a significant percentage of the cost of replacement, it

becomes economically favorable to simply order a replacement part. In such cases, the

2 Spare par.t http://en.wikipedia.org/wiki/Spare_part

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part is said to be "beyond economic repair" (BER), and the percentage associated with

this threshold is known as the BER rate.

Repair cycle

From the perspective of logistics, a model of the life cycle of parts in a supply chain can

be developed. This model, called the repair cycle, consists of functioning parts in use by

equipment operators, and the entire sequence of suppliers or repair providers that

replenish functional part inventories, either by production or repair, when they have

failed. Ultimately, this sequence ends with the manufacturer3.

This type of model allows demands on a supply system to ultimately be traced to their

operational reliability, allowing for analysis of the dynamics of the supply system, in

particular, spare parts.

Repair of repairable

In this model, repairable parts are either repaired by local maintenance capabilities, or

sent out for repair by repair providers. Generally, local repair can be accomplish simple

repairs faster and with less expense, however, more sophisticated diagnostics and

repairs, such as overhauls, require better support equipment that is expensive to deploy

to local maintenance facilities. If repair providers are unable to accomplish a repair, the

3 Optimal maintenance

http://en.wikipedia.org/wiki/Optimal_maintenance

4

item may be scrapped (or condemned), and replaced. The total time a part spends

being repaired is known as the repair cycle time4.

Replenishment

In the maintenance plan Consumable parts short-circuit this process, as they do not

allow for repair. Instead of spending time in the cycle waiting for repair, these parts are

scrapped directly, and a replacement must be obtained from a supplier. The time it

takes for a supplier to provide a replacement part is the lead time.

Performance metrics

Several logistical measures of performance, or performance metrics can be used to

evaluate the effectiveness of the repair cycle. Key performance metrics include repair

turn-around time, ready rate, fill rate, and system availability.

Military operations spending and maintenance

Military operations are significantly affected by logistics operations. The system

availability, also known as mission capable rate, of weapon systems and the ability to

affect the repair of damaged equipment are significant contributors to the success of

military operations. Systems that are in a mission-incapable (MICAP) status due lack of

4 Corrective maintenance

http://en.wikipedia.org/wiki/Corrective_maintenance

5

spare parts are said to be "awaiting parts" (AWP), also known as not mission capable

due to supply (NMCS).

Because of this sensitivity to logistics, militaries have sought to make their logistics

operations as effective as possible, focusing effort on operations research and optimal

maintenance. Maintenance has been simplified by the introduction of interchangeable

modules known as line-replaceable units (LRUs). LRUs make it possible to quickly

replace an unserviceable (failed) part with a serviceable (working) replacement. This

makes it relatively straightforward to repair complex military hardware, at the expense of

having a ready supply of spare parts.

The cost of having serviceable parts available in inventory can be tremendous, as items

that are prone to failure may be demanded frequently from inventory, requiring

significant inventory levels to avoid depletion. For military programs, the cost of spare

inventory can be a significant portion of acquisition cost.

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References

1. Integrated logistics supporthttp://en.wikipedia.org/wiki/Integrated_logistics_support

2. Spare par.t http://en.wikipedia.org/wiki/Spare_part

3. Optimal maintenance. http://en.wikipedia.org/wiki/Optimal_maintenance

4. Corrective maintenance. http://en.wikipedia.org/wiki/Corrective_maintenance

5. Spare parts management. http://en.wikipedia.org/wiki/Spare_parts_management

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