Thread: Dual wings for a flying creature?

If you had to design a flying creature for a sci-fi story, which had evolved two sets of wings, one large pair of bat/bird wings that could beat at a moderate frequency or simply extend like a soaring eagle/condor, and a smaller secondary pair of wings that would look like the wings of a fly and could beat at relatively high frequency.

In theory, would it be easier for such a creature to fly if the smaller/faster beating wings were located below or above the larger wings, and would it be better if they were slightly in front or behind the main wings? Im imagining the creature mostly gliding on the larger wings while the smaller wings help propel the creature forward.



(Im not sure if this question should go in physics, biology, engineering or science-fiction, but thanks in advance )

Lots of insects have more than two wings. You might start by just doing a Google images search to find pictures. I think you wouldn't want the wings above or below each other, because if they beat t different rates then sometimes they'd be beating in the opposite direction, and I'm not sure, but I think that would waste energy. (It might not.)

So I'd say to have the fast wings behind the slow wings, but even with them (not above them or below them). That way they can act like propellers to kind of generate thrust behind the creature, while the bigger slow wings handle guidance and lift. Just my guess, though.

On the other hand, the situation you describe sounds quite analogous to a classic World War 1 airplane, where the propellers might be thought of as the small wings, and the big wings would be like the stationary wings of the plane, and clearly the propellers were located at the front of the plane.

Let's look to nature, where the elytra of beetles serve as both wing covers and airfoils.

Most beetles extend their elytra laterally during flight, where they can act as fixed airfoils; typically, such elytra are held at a pronounced dihedral angle.

source

the forewings of beetles (the elytra) in some cases function as fixed wings

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elytra = either of the front pair of modified, usually thickened, wings in certain insects, esp. beetles, which act as protective covering for the rear wings.

dihedral = the acute angle, normally upward, between the wings of certain airplanes, designed to improve lateral stability.

soldier_beetle.jpg

Thanks Kojax and jrmonroe these were great insights. I like the beetle picture.

Fly's have a small pair of 'haltares' which move in opposition to the wing beats to offset the torque.

Something like microraptors