Yi qi and Ambopteryx longibrachium, the first dinosaurs to take to the air, had wings made of membranes like bats, but they could barely glide and were soon outcompeted by birds
Source:
https://www.newscientist.com/article/2257732-the-first-flying-dinosaurs-were-a-failed-evolutionary-experiment/?utm_campaign=RSS%7CNSNS&utm_source=NSNS&utm_medium=RSS&utm_content=home