No, but the pterosaurs might have been, because their (likely) quadrupedal launch implies they could optimize away all unnecessary muscle (read: weight) from the legs, so they inherently could optimize their body plan better.

And they also had two wings.

[0] https://en.wikipedia.org/wiki/Pterosaur

[1] https://www.youtube.com/watch?v=scAp-fncp64&t=150s

[2] https://www.youtube.com/watch?v=9TKgupAZVzE