I actually enjoyed
The War in the Air; Vol. 1
http://www.manybooks.net/titles/rale...2628226-8.html
Unfortunately, the author seems to have died before completing any further volumes.
As to fiction, what I've found fascinating is some of the young adult fiction written during WW1. For instance
http://www.manybooks.net/titles/emer...3420834-8.html
While obviously not particularly graphic, it did have a couple of harrowing descriptions that I found surprising.
Also stuff like this, the "Air Service Boys"
http://www.manybooks.net/search.php?search=Air+Service
(There are a couple others like that).
Again, probably not the most realistic, but at the same time, authentic, because it's from the war itself, not written years afterward.
One of the posters here has kindly converted some pulps to e-book format. These are overly dramatic, but often written by people who were in WW1
https://www.mobileread.com/forums/sho...d.php?t=131001
https://www.mobileread.com/forums/sho...d.php?t=143181 (Lone Eagle - WW1 flying stuff)