title: Space shuttle flight crew spatial orientation survey results.
abstract: METHODS
  A survey was distributed to 77 Space Shuttle flight crew members; 40 responded covering 71 missions. The goal was to capture historical information before Shuttle retirement and to better understand subjective experiences of illusory sensations due to the transition from 1-G to microgravity and back.
  
  
  RESULTS
  We analyzed the response data to answer four questions: 1) Do older astronauts suffer more from illusory sensations than younger astronauts? We conclude that they do not because younger flight crew had about twice the rate of illusory sensations as older flight crew. 2) Do trial head motions during re-entry in an effort to hasten readaptation to 1-G really help? Apparently not because those who made trial head motions had a 38% rate of illusory sensations whereas those who did not make trial head motions had a 15% rate of illusory sensations. 3) Do symptoms decrease as flight experience increases? Yes, as reported in other publications, although there are individual exceptions. 4) Do longer duration missions lead to more illusory sensations and readaptation difficulties than shorter duration missions? Yes, the rate of illusory sensations for longer missions was 38%, whereas it was 24% for shorter missions.
  
  
  CONCLUSIONS
  Based upon our results, long-duration missions may induce orientation problems that could have significant mission impacts.
authors.affiliation: Alion Science & Technology Corp, Boulder, CO, USA. Ronald_L_Small@yahoo.com
authors.forename: Ronald L
authors.initials: RL
authors.lastname: Small
authors.forename: Charles M
authors.initials: CM
authors.lastname: Oman
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Jones
mesh_terms: D000222:Adaptation, Physiological; D000328:Adult; D000367:Age Factors; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009949:Orientation / Q000502:physiology*; D013026:Space Flight; D018531:Spacecraft; D013037:Spatial Behavior / Q000502:physiology*; D011795:Surveys and Questionnaires; D013647:Task Performance and Analysis; D014481:United States; D014893:Weightlessness