Regarding Reliability and Availability: 1. Reliability and Availability are related, but not identical. 2. Systemic availability is, generally, the result of the combination of component reliability, component redundancy, policies, procedures, and discipline. 3. Policies, procedures, and discipline help to reduce and/or mitigate accidents. In terms of accidents and human factors: 1. Accidents cannot be eliminated, but, with proper procedures, policies, and disciplines, most can be eliminated or prevented. 2. Most accidents which cannot be eliminated can be mitigated, but, doing so often comes at a cost which exceeds the product of benefit and likelihood. We could learn a lot about this from Aviation. Nowhere in human history has more research, care, training, and discipline been applied to accident prevention, mitigation, and analysis as in aviation. A few examples: NTSB investigations of EVERY US aircraft accident and published findings. NASA Aviation Safety Reporting System When NTSB finds a design flaw in an aircraft at fault for an accident there is a process by which that error gets translated into an Airworthiness Directive forcing aircraft owners to have the flaw corrected to continue operating the aircraft. When NTSB finds a training discrepancy, procedural problem, etc., there is a process by which those discrepancies are addressed.through training, retraining, etc. For example, after a couple of accidents related to microbursts, NTSB and FAA determined that all pilots should undergo training on windshear and windshear avoidance, including microburts. etc. (There are many more examples) Owen