Downloaded from https://www.everyspec.com ADS-79D-HDBK Credible Failure: A failure that is supported by engineering test, probabilistic risk analysis, or actual occurrences of failure. Critical Safety Item (CSI): A part, assembly, installation equipment, launch equipment, recovery equipment, or support equipment for an aircraft or aviation weapons system that contains a characteristic any failure, malfunction, or absence of which could cause a catastrophic or critical failure resulting in the loss or serious damage to the aircraft or weapons system, an unacceptable risk of personal injury or loss of life, or an uncommanded engine shutdown that jeopardizes safety.
Damage is considered serious or substantial when it would be sufficient to cause a ―Class A‖ accident or a mishap of severity category I. The determining factor in CSIs is the consequence of failure, not the probability that the failure or consequence would occur. For the purpose of this instruction ―Critical Safety Item‖, ―Flight Safety Critical Aircraft Part‖, ―Flight Safety Part‖, ―Safety of Flight Item‖, and similar terms are synonymous. The term Critical Safety Item should be the encompassing term used throughout this handbook. Data integrity:
Data Integrity refers to the provisions taken so the data is unchanged (not missing or corrupted) from when it was initially acquired by the CBM system as reflected in RTCA DO-201A, Section 2. Data Mining: Data Mining refers to reviewing or processing the data in order to obtain information or knowledge. Depending on the format of the stored data, this process can range from signal processing of sampled measurements to queries performed on database tables. Data reduction: Data reduction refers to any action taken to reduce the volume of the measured data without compromising the value of the data with regard to its intended purpose.
Data reduction is often performed as part of the acquisition process in order to reduce the burden on storage capacity and may be broadly interpreted as actions ranging from down sampling (volume reduction) to filtering (smoothing). Diagnosis: The process of analyzing parameter data associated with a suspected fault and postulating the cause of the fault. Digital Source Collector: An onboard aircraft data recording system used to collect CBM data. Exceedance: An event in which the equipment operates outside of its specified limits. False Negative: A fault is not indicated by the Digital Source Collector but found to exist by inspection. False Positive:
A fault is indicated by the Digital Source Collector but not found to exist by inspection. Failure: The loss of function of a part, component, or system caused by the presence of a fault. Fault: An undesired anomaly in an item or system. Ground Air Ground Cycles: Relatively low-frequency large-amplitude load cycles occurring during a given flight, but not present in any single flight condition. Examples include rotor start and stop cycles and load fluctuations between the various flight conditions encountered during performance of a mission. 6