||Measuring situation awareness (SA) and situation understanding (SU) is an important topic for Command & Control research. Virtual simulations (VS) have been proposed as a suitable method for measuring SA/U, but, there is little research into how to build scenarios for VS so that SA/U can be measured reliably. In this study, we used two different VS scenarios and the Quantitative Analysis of Situation Awareness (QASA) method to measure, and provide feedback on, actual and perceived SA/U. Two VS scenarios were tested in Estonia with 36 trainees. The results of the different scenarios were compared to establish whether the scenario storylines and authoring process resulted in differences in SA or SU. We conclude that reliable assessment results were produced with both authoring processes, and further suggest that the Collaborative Authoring Process Model for Virtual Simulations (CAPM) be used for VS creation.