I want to stay within a reasonable size range per age for my humanoids and for gravity the same as earth's, the most reasonable size range is the human size range.
I found out on Stack Exchange that flying at a supersonic speed without some form of air compression(namely turbofans) is impossible.
But they also said that with normal human parameters(weight of 120 lbs, height of 5 feet, normal arm and leg length) and an arm winspan of 5 feet(2 feet per arm + 1 foot for the body) and a leg wingspan of 7 feet(3 feet per leg + 1 foot for the body and assuming that the flaps are synchronized and the arms are flapped twice per second and legs flapped once per second that the humanoid will be 6 times too heavy to fly, much less fly super fast at the same atmospheric density as Earth.
But doesn't atmospheric density depend on gravity as well as composition? I mean sure their atmosphere is more like 30% oxygen than 27% oxygen but I don't think that is enough of a change in composition to make flight possible.
But I don't want them too big or the Square Cube Law will make normal life impossible without changing bone size and/or composition. And I don't want them too small or they might as well not be humanoids.
I am not sure how well hollow bones will work. I mean for one thing, if there was less compact bone, it would probably be replaced by bone marrow. Plus, if the bones were hollowed out, fractures would be much more of a concern as would osteoporosis in pregnancy.
Basically I don't know what to change in order to make my humanoids able to fly because every change I can think of has its own negatives as well as improving flight chance.
I found out on Stack Exchange that flying at a supersonic speed without some form of air compression(namely turbofans) is impossible.
But they also said that with normal human parameters(weight of 120 lbs, height of 5 feet, normal arm and leg length) and an arm winspan of 5 feet(2 feet per arm + 1 foot for the body) and a leg wingspan of 7 feet(3 feet per leg + 1 foot for the body and assuming that the flaps are synchronized and the arms are flapped twice per second and legs flapped once per second that the humanoid will be 6 times too heavy to fly, much less fly super fast at the same atmospheric density as Earth.
But doesn't atmospheric density depend on gravity as well as composition? I mean sure their atmosphere is more like 30% oxygen than 27% oxygen but I don't think that is enough of a change in composition to make flight possible.
But I don't want them too big or the Square Cube Law will make normal life impossible without changing bone size and/or composition. And I don't want them too small or they might as well not be humanoids.
I am not sure how well hollow bones will work. I mean for one thing, if there was less compact bone, it would probably be replaced by bone marrow. Plus, if the bones were hollowed out, fractures would be much more of a concern as would osteoporosis in pregnancy.
Basically I don't know what to change in order to make my humanoids able to fly because every change I can think of has its own negatives as well as improving flight chance.