On December 12, 1985, a charter airline carrying 248 United States soldiers crashed and burned after a refueling stop in Gander, Newfoundland, killing all on board. After the crash, family assistance workers were appointed to help the surviving family members of each dead soldier. This study attempted to: (1) identify the major areas of stress for disaster family assistance workers; (2) examine the relation between exposure to these stressors and health; and (3) locate risk factors, or resistance resources that might moderate ill effects of exposure. A survey instrument assessed duration and intensity of family helping activities, illness indicators, psychiatric symptoms, psychological well-being, and social and personality variables at 6 months after the crash and again at the 1-year point for 131 family assistance officers. The results indicated a dose-response effect between exposure measured at Time 1 and illness levels at Time 2, an increase in symptoms, and a change in psychological well-being over time. Social support was a moderator of the exposure-symptoms relation, and both social support and personality hardiness were moderators with respect to Time 2 illness and change in psychological well-being. Other evidence suggests that prior experience with death and grief, and having volunteered for the family helper role also reduced the risk of developing ill effects. (Author/NB)