AVweb This story originally appeared in KITPLANES. Flying any aircraftâhomebuilt or notârequires the pilot to be alert. The person at the stick has to have their brain firing on all cylinders. But occasionally they donât. Sometimes the pilot is flying on the wrong medicine, legal or not. Sometimes the pilotâs body has unknown (or even known) medical conditions that flare up at exactly the wrong time. But how often does it happen? Itâs certainly not just a homebuilt issue. But pilot issues such as substance impairment or medical are already identified in my 1998â2017 homebuilt accident database. Itâs a pretty easy task to extract them. Letâs lop off this low-hanging fruit and see where it takes us.