I can understand Super-beings' great strength and some of their other powers, but flying is hard to justify.
I want to consider only superheroes that can actually fly rather than merely jump tall buildings.
My theory is that their body hair can be controlled like so many cilia on a microorganism. There are tiny muscles in the skin of ordinary humans that raise the hairs when we are cold (goose bumps). In superheroes these could be controlled independently to create a wave motion.
This could explain why they have to wear close-fitting spandex - it allows the hairs to poke through. Alternatively they could be nearly nude and the 'spandex' merely tattooed on.
(1) If all the hairs on a human-like body beat in a wave motion, what characteristics would those hairs have to have to enable flight? Assume that they can beat with the fine control of a fly's wings. At a pinch, they could even have the same shape.
Please assume that the muscles that power these hairs have super strength and speed and that the hairs are made of super strong material.
You may wish to take the following hair characteristics into account:
frequency of beating
(2) If we designed the perfect hairs and muscles with roughly the same bodily distribution as human hairs, would the superhero be able to take off?
I forgot to mention that the hairs are invisible.
Shall we try bumblebees? Each can lift about 252 millionths of a pound, about 10 times as much as a housefly. Total requirement: 437,240 bees. https://www.washingtoncitypaper.com/columns/straight-dope/article/13044234/straight-dope-how-many-houseflies-would-you-need-to-lift
The above article gives some useful figures for being lifted by insects. Remember however that we don't need the insects' bodies because the muscles are part of the superhero's body and the superhero has some huge, unknown energy source. Further the hairs/wings are made of super materials so we are not limited to what a fly can do in terms of strength/endurance.