Like "Coasting", my current WIP, "Offshore" is proving that time travel is possible.
It was first written in 1982, when I was sailing on Supply Boats not unlike the Sapphire Sea and recalls some moments of that time with absolute clarity. Others I had to think about...like the lookout system for night steaming.
With such a small crew, nine men, the Skipper and the Mate had to do six-hour watches and it was important to ensure that at least two men are awake during the hours of darkness (radar is an aid, not an answer to safe night steaming) With two engineers and only five ABs, one of which is committed to the engine room while another acts as cook, that leaves three men to cover the hours of darkness on the bridge. Logically, each man should do four hours as lookout and have eight hours to sleep, but it didn't fit with my vague memories of the time and the manuscript written in the period contained no specifics.
I went back to friends from those days, largely engineers, and found I wasn't the only one whose memories were vague. Worse, everyone remembered the system differently.
My next source was the personal journals I kept at the time (records not so much of daily events, but of thoughts and conclusions it was rarely politic to express aloud. A form of lightning conductor that kept me out of trouble more times than I can remember) Their inconclusive nature and the variance of other peoples' memories convinced me that the system must have varied from ship to ship and from crew to crew (we normally swung on and off the ship as a group, some crews staying together for years).
Talking about something so specific with friends who shared the experience, generated some marvelous tales of the times and characters (A skipper everybody called "Fruit Box" because he was so short he had to carry a wooden fruit box to see over the wing of the bridge when manoeuvring alongside a rig).
The other element of interest was the different ways others recalled the same incidents, some because they were on different supply boats, others because of different perspectives.
It was a great interlude from writing.