Defence Test and Evaluation Roadmap 2008

T&E defined:
T&E can be defined as a process that obtains information to assist in the evaluation or support the objective assessment of a capability system with known confidence, and to confirm whether or not a risk is contained within acceptable
boundaries across all phases of a system’s life cycle.

Purpose of T&E:
The fundamental purpose of T&E in a Defence system’s development and acquisition program is to identify the areas of risk to be reduced or eliminated. During the early phases of development, T&E is conducted to demonstrate the feasibility of conceptual approaches, evaluate design risk, identify design alternatives, compare and analyse trade-offs, and establish satisfaction of operational requirements.

As a system undergoes design and development, the iterative process of testing moves gradually from a concentration on Development Test and Evaluation (DT&E), which is concerned chiefly with attainment of engineering design goals, through Acceptance Test and Evaluation (AT&E) to increasingly comprehensive Operational Test and Evaluation (OT&E), which focuses on questions of operational effectiveness, suitability and survivability.

Although there are usually separate Development Test (DT) and Acceptance Test (AT) events, DT&E and AT&E are not
necessarily serial phases in the evolution of system development. When appropriate, combined or concurrent DT and AT or Operational Tests (OT) are encouraged. This concurrency of testing can contribute to savings in costs and time in many
circumstances. Significant risk identification and mitigation is possible when activities such as OT&E are conducted early in a capability system’s life cycle.