Flat Flying Wing glider

This is the first model which I have uploaded, so please let me know if there is any issue with the file.

Print Settings:

Infill: 100%

Seam Position: random

Perimeters: 3

This is a quick experiment to make a glider that could be taken directly from the printer and flown without bends or adjustments.  I had a little bed adhesion trouble, so disks were placed at the bottom of the thin vertical surfaces.  These disks are just for bed adhesion and should be cut off.  If you have really good bed adhesion, you could try to trim off these disks in the slicer to make is so that there is really no work between printing and flying.

100% infill will result in a good CG position.

I found that setting seam position to random helped the thin wing tip surfaces print better.  If the seam is at the same location, the sloped surfaces tended to either not print successfully, or to have warps.  The random seam may result in surface bumps, but that is fine for flight.

I've only printed in PLA.  It is strong enough to survive landing on grass, and getting stuck in bushes.  It got in the pool once and glided very slowly all the way across while only sinking a little bit.

The way the tip surfaces are designed, it has built in incidence angle, so there is no need to make any bends.  The tip surfaces also act as dihedral angle, which stabilizes roll fairly well.

To throw it, place your thumb and middle finger on each side of the nose, and place your index finger behind the wing (see included picture).  Give it a good flat throw.  It flies relatively flat.

There are a few admittedly untested details that may or may not actually be doing anything.  First, the layers of the wing step up close to the leading edge to form a smoother leading edge.  Each layer step will have a recirculation bubble in front of it.  These recirculation bubbles sort of form a false surface for the main flow streamline to go over.  The aft steps down are spread out to sort of mimic the narrowing of a typical airfoil.  There are just enough layers to get a reasonably stiff wing (e.g. it doesn't just flop down when it is picked up).  The trailing edge has a short vertical lip.  This is basically a Gurney flap.  This vertical lip will have a recirculation downstream, which allows the main streamline to turn up a little bit.  If this is working, it is a little like a reflexed wing and provides a little nose up moment which is helpful on a flying wing.  Since the wing has to be flat, any washout (wing twist) can't be done.  To get around this, the canted surface at the tip provides a location where a downward incidence can be included.  The canted surface also provides a dihedral effect, since the main wing is flat.  The vertical surface at the tip provides yaw stability, but equally important, it joins with the canted surface to make a strong triangular structure.  The small vertical surface is just there to help the canted surface print, since it is a fairly long unsupported run without it.  In reality, the Reynolds number is so low for this little glider that these aero tricks are probably not working.  It was still interesting to try them out though.  For those interested, look up Gurney flaps, and none planar c-wings to explore some interesting aero that can be worked into even these simple little toys.