- Previous researchers examining transfers of control from semi-autonomous to manual driving have found that younger drivers engaged in a secondary task while in automated mode need at least 8 seconds to achieve the same level of situation awareness as drivers always in control of their vehicle (Samuel et al., 2016). It is likely that middle-age drivers, with their increased driving experience would require less time. To test this hypothesis, middle-age drivers participated in a driving simulator experiment where they were asked to either drive manually (control) or with a simulated autonomous system (experimental conditions). While in automated mode, drivers either received an alert 4s, 6s, 8s, or 12s prior to the presence of a latent hazard. The proportion of latent hazards anticipated was examined. The results were consistent with the hypothesis that middle-age drivers were better at anticipating hazards overall and were faster to achieve appropriate situation awareness associated with manual driving than younger drivers.