ADS-79D-HDBK Downloaded from https://www.everyspec.com reality. They provide realistic data with usually well controlled and documented ground truth information. Sometimes, physical experiment may not be a viable option for validation due to complexity of the testing, excessive cost of physical experiment, or even infeasibility to perform such a test. As an alternative, numerical experiments may be used to generate simulated features or signatures for further comparison with the computational model. This approach has been used in the nuclear industry and gains more popularity in validating diagnostic and/or prognostic algorithms.
Often, its benefit in cost effectiveness may be offset by the lack of representative realistic data. If numerical experiment is used in validation, efforts needs to be made to ensure the relevance and quality of the simulation model utilized. K.5 MAINTENANCE CREDIT V&V PROCESSES AND PROGNOSTICS Maintenance Credits are acquired when a HUMS system DSC can modify or replace the existing industry standard maintenance interval for a given component. Thus, the HUMS system DSC must thoroughly prove that its estimation of the component‘s condition, that is to modify or replace the current standard, is accurate.
A verification and validation process is provided in this section that is to be used to achieve Maintenance Credit at a component level. For the sake of simplicity and flow of explanation, the process below has been partitioned into subsections. The subsections are ordered in congruence with Figure K-5. Sub-Section 1: The overall Maintenance Credit V&V process begins with the identification of the component for Maintenance Credit. The identification step should account for the component‘s current maintenance practice as outlined in its RCM process, the helicopter platform‘s maintenance manual and its flight manual.
The analysis of these three components will help collect the baseline maintenance plan. Sub-Section 2: Once the component has been identified, the next step is to determine the severity of the component. The severity classification will later be used in determining the probability of false positive (PFA) of the credit methodology during development. For more information on the severity categories, refer to Appendix D of ADS- 79D, ―Minimum Guidance for Determining CIs/HIs for Propulsion Systems.‖ 198