Air safety pinned on isolated controllers Resource Type: Article Published: 2011 The problem of acute fatigue among air traffic controllers has been known. It was studied by sleep scientists genuinely concerned about the workers and public safety. Studies have shown that the kind of shift scheduling to which controllers are subjected affects behavior in the same way several alcoholic drinks would. That is especially true of constant shift changes and stacking eight-hour shifts as close together as possible, like working five shifts in three days.