Large screen projections (LSP) are applied in control rooms in order to facilitate a shared overview of running processes for shift staff. So far, little is known about the teamwork-related impact of LSP. It was assumed that LSP affect a) the congruency of mental models of interdependently working teammates and b) team performance. Congruency is a prerequisite for effective teamwork due to its impact on team-coordination processes. Shared mental models (SMM) regarding task and team interaction affect mutual expectations regarding the teammates’ behaviours. They facilitate tacit coordination, mutual performance monitoring, and proactive offering of support. In a pre-post-test design, 21 operator teams of 3 engineering students each (N = 63), divided into two groups (LSP on/off), were investigated regarding their SMM acquisition within a furnace simulator. Following 45 minutes of training, task- and team-SMM were measured. Afterwards, the groups worked at the simulator “SteelSim” either with or without LSP to produce raw iron for 45 minutes. This was followed by the post-test SMM. Team performance was measured as the amount and quality of produced raw iron. It was found that although LSP did not significantly affect task and team-interaction SMM, LSP increased team performance significantly.