The FAA requires both aircraft maintenance logs and commercial pilot logs showing flight hours. The personal log referred to in my post is the required FAA pilot log. I was surprised that the CG didn’t require a seaman’s log when I started sailing commercially but I continued the habit since I was used to keeping track of trip details from keeping a FAA pilot logbook.
PS I don’t remember if the FAA requires private pilots to maintain a log of flight hours but good practice anyway.