finch that cant fly

Question
We built an outdoor aviary (7' x 6' x 6') and have begun putting zebra finches in.  We bought several finches the other day and have found that one of them is unable to fly.  There doesn't appear to be anything wrong with her wings and there don't seem to be any feathers missing.  She seems otherwise healthy and energetic.  Her wings don't droop and she flaps them when she tries to fly, but all she can do is hop.  This is not a baby - her beak and legs are orange.  We have put her in a small cage with food and water easily reachable, and hung the cage inside the aviary where she can still socialize with the other finches.  Do you know if she will every be able to fly?

Answer
It could be that her wings just aren't strong enough. I would put the bird in the avairy and just put food in the bottom for her. This will get her wings nice and strong so they can carry her. The smaller cage will only cause more harm because she will never be able to strengthen her wings.