I caught this article in the Daily Mail about longest duration flight. The article reminded me of a story I read many years ago about a record set in 1935 that still easily beats the Zephyr S. What's more, that flight back in 1935 was manned by two early aviation pioneers, unlike the drone flight the Daily Mail writes so encouragingly about.
I remember reading the story about the brothers, Fred and Algene Key, who decided to keep their Curtiss Robin J-1 Deluxe in the air for as long as possible. They stayed up there above or around Meridian for 27 days. They received supplies in midair 432 times. Their wives would prepare meals and send them up with the refueling pilot. It's a fascinating story.
wag put it, that means they spent 27 days relieving themselves on Meridian. Nobody mentions that part in the history books.