I recently tried a similar recipe for oven-baked wings with no added fat.
I had four fresh wings that I cut into sections and patted dry. I shook the eight wing sections in a brown paper bag with a flour coating that contained onion powder, garlic powder, paprika, salt, black pepper, cayenne pepper, and baking powder. Placed them on a wire rack over a baking sheet and refrigerated them for a couple of hours. I baked them for 30 minutes at 250f and increased the temp to 425f for another 40 minutes. I tossed the wings in a mixture of Frank's Red Hot sauce and butter then returned them to the oven for an additional 5 minutes to set the sauce.
I think the resting time in the refrigerator helps the coating to adhere to the wings while the baking powder draws moisture to the surface and helps to crisp the skin.