Is high-frequency flapping (similar to how dragonflies fly) an efficient lift production method at high Reynolds numbers?
I have not seen anyone develop wing suits with high frequency flapping, is it efficient only at the insect scale? A few million years ago there used to exist dragonflies with wing spans around 70cm - correlating with the high oxygen content in the atmosphere at that time - so is this possible at larger wingspans too?
I'm thinking of something like the parademons in Justice League: