In a study of pilot suicides from 2002 to 2013, nine cases were identified as definite suicides (with evidence of suicide notes, previous attempts, or a history of mental illness), with five additional cases of undetermined cause that may have been suicides.
In a study of pilot suicides from 20022013, eight cases were identified as definite suicides, with five additional cases of undetermined cause that may have been suicides. 
