Yes! Knights of the Sky was a fairly poor simulation.. but the incredible little encyclopedia that came with it detailing von Richtoffen's entire career, letters, memoirs and some superb photographs was worth the £30 on it's own!
Alas.. I don't have a working copy of the game anymore though.

( My version was for the ancient Amiga 500+!! LOL!
Still. I can reccommend Air Warrior 3 as a suitable replacement -- the games are very similar in the heads-up dsiaplay and just as clunky. ;o) Speaking of WWI flight sims... does anyone remember the excellent
Chock's Away! that wasout on the old Arcimedes? Now that
was a King among flyers!