Component kill criteria. A Litterature review

A literature review has been conducted in order to find methods, experimental data and empirical relationships that can be used in order to define kill criteria for components. Only damage caused by penetration is considered. Kill criteria for components are used in simulations of weapons effects in various types of targets. The criteria are used to judge whether a component has stopped working, works with reduced capacity or works normally after the damage. Based on the conditions of each component, a fault tree can be used in order to describe which of the targets main functionalities that are affected or not by the attack. Detailed information regarding vulnerability and lethality codes are most often classified, as well as much of the information used as input data to those codes. The reason for classification can be to protect the information it self as well as to protect the economic value the information represents. Hence, there is little international scientific sharing. Despite the classification problems, there are some old,descriptions (mostly from US) , on how kill or damage criteria have been assessed. These are often based on the concept of vulnerable area, which describes the portion of the projected area in a direction that is vulnerable for a certain threat. For some special component types, like cables and wires, there are empirical relationships between the kill probability as function of fragment mass or size and impact velocity. Empirical relationships can also be found in international peer review scientific journals, but these are extremely rare. These published relationships are mainly focused on kill criteria for satellite components exposed to the threat of space debris, and the impact velocities are thus higher than for normal weapons effects. There have also been a few attempts to establish almost analytical relationships, but they often seem to end up requiring some kind of limiting values. Time is sometimes included as a factor in the criteria. It is then used either to decide when the component should be considered failed or when the failed component affects any connected system. Neglecting time as a factor gives limited possibility to handle results such as the enemy vehicle stops firing at you immediately or some minutes or hours later. The lack of international scientific cooperation has resulted in an absence of common terminology and standard formats on how component criteria should be formulated, which in turn complicates exchange and cooperation within this field. The need of international cooperation will probably increase since the same equipment is used by several nations and often in joint missions. A short summary on how different vulnerability/lethality assessment codes use kill criteria is given, partly in order to show the variations and lack of standard format.