1914-1918 1999k-499 2012b-825 accidents aerial aerialoperations aeronautics aerospacemedicine airpilots anxiety aviation control diagnosis engineering engineering(general) fearofflying history humanfactors industrial industrialpsychology medicalcare methods militaryoperations militarypsychiatry occupationaldiseases occupationalhealth prevention psychologicaltests psychology safetymanagement safetymeasures selectionandappointment technology warneuroses wd730 wd754k54a1999 worldwar worldwar(1914-1918)