This is likely not a new thing but for a lot of buyers-not-builders a heads-up.
At 196 hrs I changed the oil and was to begin my FWF inspection. Events limited me to the change and recowled for 1 hr flight. Cowl removed and found two screws mins in 1 hr flight time, one fell from lower cowl at removal.
I question my observation skills not finding one missing just an hour before, so having found one, would conclude that once loose, these screws can back out really fast!
As Walt and Vic always say "put-a-wrench-on-it" to check the torque!! I was not wise to these particular fasteners, but should have been. Shame face applied . .
So - I will reinstall, torque and recheck every 10 hours to be sure they are tight and follow up with additional information.