I'm not sure what times you are on, but I'll fill ya in on the times I know of.
Tuesday afternoon, around 1 pm Central, the finnish squads come into the AvA for their Squad times. They are a European time zone squad.
On Tuesday and Thursday, at 9pm Central, our Squad flies our Squad time. Other Squads come in on other nights, but normally around the same time, 8 to 9pm Central.
Most night's, I'd say the numbers get good around 7 or 8 pm Central.
On weekends, it seems to depend on whether somebody has thrown together a Good Mission. We've seen over a Hundred for a good mission, announced in advance.
Hope this helps ya out a bit, and welcome to the AvA