My Silkie's (pure from reputable breeders) can't fly worth beans. They think they can, and will run across the ground flapping their wings but they never get off the ground
My Cochin roosters can fly well enough to get over a four-foot fence, but the big fat hens can't get more than a couple inches off the ground.
Polish are great fliers, so I recommend against them.
My Seramas fly well, but they are normal feathered and as Ra said I'm sure the silkied wouldn't be able to (Seramas also have great personality!)
Anything silkied can't, and frizzles can't get far enough off the ground to count. Also anything with a lot of weight and little wings (Cochins, Cornish X, any meat breed) can't (at least not the hens, Roos tend to be slimmer and fly a little better)
What are you wanting them for? It's gonna be hard to find a layer breed that can't fly, but meat and pets that can't fly very well are plentiful :-Di