Maintainability Demonstration (M-Demo)

Overview

The basic objectives of designing for maintainability are to meet the operational readiness requirements for the product and to reduce support costs. An engineer committed to these objectives will continually challenge the design to uncover weaknesses and potential maintenance problems. The objective is to design in maintainability and if this objective is not met then corrective actions will have to be incorporated into the design later in the equipment's life cycle at a significant expense. The primary emphasis of the maintainability program is to identify and correct maintainability problems early in the design process when correction simply requires changing drawings. The M-Demo is a formal process conducted by the product developer and the end customer to determine whether specific maintainability requirements that have been specified have been achieved. Demonstration testing requires a formal test plan be developed that uses defined methods of analysis to determine compliance.

M-Demo Goals

An M-Demo test would establish what criteria will be tested based upon given parameters. These would include the verification of the many maintenance tasks, which are being proposed to be implemented on a system. In the implementation of each maintenance task (corrective and preventive), all the necessary resources to permit an effective repair or maintenance activity would be assessed. This would include all supporting elements, such as the systems diagnostics capabilities, the required tools (common and special), support equipment and even the skills of the maintainer.

Another goal of the M-Demo would be to identify potential problems in the implementation of specific maintenance tasks, hence find fixes prior to fielding the system. The results of the M-Demo could also serve to provide feed-back to the Product Support Analysis (PSA) effort. The M-Demo process is definitely subject to careful planning and to ensure that it is implemented in an effective manner.

Test Plan or Test Procedure

The M-Demo should be guided by a test plan or for smaller equipment, a test procedure; these documents would generally detail:

• Test objectives - identify which requirements will be validated to ensure their compliance to the technical performance requirements of an equipment or system.
• Test approach - illustrates how the test will be implemented and the proposed test strategy.
• Ground rules - discusses how the test will be implemented under what conditions, what the test sample size should be. This sample size maybe dedicated by the customer, for example they may require 50 failure modes to be tested, out of a candidate list of 200. Also maintenance tasks may also be required to be demonstrated under the operational conditions, to which the system will finally be fielded.
• Equipment to be tested - this section would identify the equipment configuration to be tested.
• Team members -  include the key persons who will have direct involvement in the implementation of the M-Demo, and could include the test coordinator, Reliability, Availabililty and Maintainability (RAM) engineer and the customer, etc.
• Schedule - would detail all of the test activities including Test Readiness Reviews (TRR), through the test implementation to the development of the test report.
• Data to be recorded - the type of data to be collected may include the recorded maintenance task elapse times, observations made against diagnostic routines and remove and replace tasks, taken into consideration accessibility issues and required tools and human factors.
• Special rules, criteria - there may be specific criteria which must be determined and validated. For example the witnessing of specific maintenance tasks by the customer.

It is important to remember that the approach to the M-Demo of the system must be synchronized and worked in harmony to the efforts as detailed in the PSA effort. These two efforts follow the same maintenance concept, and as the PSA effort is implemented and developed, the final maintenance philosophy of a system will be firmed-up and finalized. Both of these drive what the M-Demo will need to assessthe effectiveness of the planned maintenance activities.