Scope and object In an increasingly harsh economic context (tighter performance requirements@ shorter development cycles@ reduced cost of ownership@ etc.)@ it is essential to ensure product maturity rapidly and@ in any case@ by the time of commissioning. It is with a view to remedying shortcomings in traditional development methods that "highly accelerated" tests have been developed. The main underlying principle behind this new type of test strategy is as follows: rather than reasoning in terms of conformity with a specification and simply performing conventional tests@ we on the contrary attempt to push the product to its limits by applying environmental stresses and/or stimuli of levels higher than the specification. The aim is thus to take full advantage of current technologies@ by eliminating defects which generate potential failures@ as of the first prototypes. A well-conducted accelerated test process should@ in a relatively short time@ lead to a significant increase in the robustness of a product@ as early as the initial prototypes stage at the beginning of the development phase@ thus accelerating early maturity of this product. Furthermore@ identification of the margins available on a "mature" product helps design and size its future environmental stress screening profile more accurately@ by increasing the severity of the loadings applied to just what is needed@ leading to a particularly significant boost in the efficiency of this environmental stress screening process. The object of this PAS 1) is to specify the targets assigned to the highly accelerated tests@ their basic principle@ their scope of application and their implementation procedures. This guide is thus a methodological document aimed at facilitating drafting of the specification and then performance of highly accelerated tests by the programme managers. It is primarily intended for programme managers@ designers@ test managers@ and RAMS experts. This guide concerns all programmes@ in particular aeronautical@ space and armaments programmes. It primarily concerns the industrial firms in charge of designing@ developing and producing components built for these programmes@ but also their customers who@ in drafting contractual clauses@ may require that their suppliers implement highly accelerated tests. The recommendation applies to all types of equipment used in systems developed in these programmes@ whatever their nature (electronic@ electromechanical@ mechanical@ electrohydraulic@ electro-pneumatic@ etc.) and whatever their size@ from "low-level" subassemblies (PCBs@ mechanical assemblies@ connectors@ etc.)@ up to components or component groups. NOTE Presently@ there are no documentary standards for highly accelerated tests. This recommendation thus relies on a number of documents which are not standards@ which are of various origins and which are usually very recent@ as well as on other more standard documents@ but not specifically dedicated to highly accelerated tests. 1) Proposed by a working group comprising representatives of the aeronautical@ space and armaments industries (customers and suppliers)@ as well as representatives of laboratories specialising in testing.