I remember when Dawn of Aces came out. It held the masses interests for about 2 months, then DOA arena's population fell to about 5% to 10% of the main arena's population at any given time.
And I remember why, too.
WWI air combat was terribly boring and repetitive compared to WWII air combat.
For starters, the planes are amazingly slow. It took forever to get into a fight.
Secondly, there wasn't enough difference in the different plane's top speeds to make disengaging from a fight a possibility. As such, you would think that this would lead to lots of "fights to the death" but...
...The planes are made of wood and fabric and the guns are few and weak. You could unload your entire ammo supply into a plane and do nothing but poke holes in the fabric all over it, and it could still keep on flying as if nothing happened. You would occasionally hit something critical, like the engine, fuel, or pilot, bit it seemed 75% of your hits had no appreciable effect.
So typical 1v1 dogfights frequently had their winner determined by who still had plenty of ammo. Or...
...who brought along the most friends. 4v1 fights seemed very typical, and it seemed the only reliable way to actually shoot an enemy down due to the sheer weight of ammo that could be aimed at a target.
Anyway, like I said: very repetitive and boring.
-Llama