To quickly acquire training evaluation outlines during planning, which device should the commander implement?

The Army Training Network (ATN) METL Viewer is the most appropriate choice for quickly acquiring training evaluation outlines during planning. This tool is specifically designed to help commanders develop training plans that align with the Mission Essential Task List (METL), which is crucial for ensuring that training is focused on the skills and competencies that the unit needs to maintain operational readiness.

By utilizing the METL Viewer, commanders can access and visualize the tasks that their units need to train on, which helps in efficiently preparing training evaluations and outlines. It allows for easy retrieval of relevant tasks, fostering a structured approach to training management. This visibility supports effective planning by ensuring that all training efforts are aligned with the overarching mission requirements.

While the other tools mentioned, such as the Training Management System, Army Knowledge Online, and Army Learning Management System, provide valuable resources and information for training management, they do not specifically focus on the quick acquisition of training outlines tied directly to the METL, which is the critical need highlighted in the question.