WW1 biplanes gets my vote, same as I would vote in the case of submarines

. Though in the case of flight sims, beyond my standard reasons for loving WW1 warfare sims, I can add that since I'm a total disaster and nut with flying sims, the considerable lesser number of keys and options makes it much easier for me to survive some minutes more before being killed
I enjoyed very much Flying Corps some years ago, and the printed maps were lovely -Man how I miss the sims of those years, they knew how to do good sims back then, enriched with thick manuals and extra stuff- but lately I have not seen any exciting WW1 flight sims out there in stores