Why prognostics for avionics?

Prognostics, by providing early information on potential equipment failures, permit maintenance to be transformed from a purely responsive (and hence largely uncontrollable) activity into one that can be planned and controlled. The ability to plan and control maintenance activities is becoming increasingly important because of the shortage of skilled personnel and the complexity of current avionics products. The benefits of prognostics are well established for mechanical and electromechanical equipment, and this motivates the extension of the technique to the electronics field. But there are very large differences between mechanical and electronic components in failure mechanisms, in the design process, and in the physical dimensions of the parts subject to failure that preclude direct migration of the prognostic techniques. These differences are examined in detail and a procedure for developing prognostics specifically targeted at solid state electronics is suggested