In spite of an immense increase in interest in helmet-mounted displays (HMDs) over the pass two decades, there have been few studies on head motion while using HMDs in operational flight. Rotary-wing flights conducted using a number of HMD configurations have resulted in a head position database that will be useful in filling this void. Various analysis techniques have been applied to investigate characteristics of roll (tilt) head position distributions for a slalom flight maneuver for four visual environments: good visual environment (daytime, unaided), night vision goggles, HMD with thermal imagery, and HMD with thermal imagery and symbology.