ESDU 08004 is an example of risk analysis applied to a climb-gradient performance requirement as specified by the Certification Standards. The example considers whether the specified margin in climb performance of a large jet transport aircraft with one engine inoperative is correctly sized for an acceptable level of safety.

This Item 08004 is one of a series of examples that compliment a parent Item, ESDU 08003, that introduces the treatment of risk within the context of the performance of commercial air transport. The concept of risk is introduced in relation to what is considered safe by the aircraft operators, by the official bodies responsible for regulating air transport and implicitly by the users of the service. Risk is classified in terms of the severity and consequences of an event, together with the probability of the occurrence of that event. The term "unit of risk" is introduced to quantify general risk and is seen as either events based or time-based.