Engineering and testing for reliability

Those engaged in research have been striving for new approaches to current engineering demands. New materials, new devices, new designs and, above all, simplification of fundamental concepts are required to provide reliable operations in the field. The logistics of many highly complex operations have been developed. The problem that must be solved is how to develop and produce units that will reliably perform these operations. In some cases reliability means seconds, minutes, hours, days, or years of unfailing operation. A booster for quickly getting a heavy plane in the air need perform only for a few seconds. The same is true of some rocket engines. A laggard performance or failure to operate may mean the failure of the mission. The engines or turbo-jets of a plane are expected to operate many consecutive hours without failure. In many missiles, however, although some components need only operate once, there must be almost absolute certainty that they will operate when required. This applies to those stocked for some time. Time must not reduce the probability of their operation. In all such instances reliability and dependability are practically synonymous.