I have Flying Corps Gold but wasn't aware it was playable online. In fact, in the 6-7 years I've had it, I've only been able to play it a few times - for some reason, it's never worked that well on my computers (and they are all more than qualified to meet the game's requirements). Instead, I'd recommend playing Red Baron 3D online, since there's much more available to support it, including a wealth of new mods which have improved the appearance and character of the original game. Check this link for some sites:
http://h.webring.com/hub?ring=redbaron2